Neoplasia Chapter 7 Lecture (Putthoff) Flashcards

1
Q

What causes Cancer?

A

Cancer is a complex group of diseases with many possible causes: genetics, tobacco, diet and physical activity, sun and UV exposure, radiation exposure and cancer, other carcinogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How are different cancers alike?

A

In all cancers, cells grow out of control and spread into surrounding tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Cancer is a genetic disease? Does this mean it is inherited?

A

No, it means it is caused by changes to genes that control the way our cells function, especially how they grow and divide; acquired mutations over time, not necessarily inherited!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is another cause of lung cancer that is not related to smoking? Which population is this type of lung cancer seen in?

A

Peripheral scar carcinoma also leads to lung cancer. Usually seen in older women. NOT caused by smoking!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How did cancer get its name?

A

Cancer usually has a spiculated, undefined border that looks like crab legs and “cancer” is crab in latin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Generic term for all malignant neoplasms?

A

Cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

“new growth or form;” results from genetic alterations that are passed down to progeny of tumor cells. These genetic changes allow excessive and unregulated proliferation that becomes autonomous (independent of physiologic growth stimuli); occurs in a spectrum from benign to malignant

A

Neoplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

_____ (swelling) was first used as one of the characteristics of acute inflammation. Now frequently used by physicians as a synonym for neoplasia

A

Tumor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Study of tumors (neoplasms); can be classified into medical, surgical, pediatric, etc

A

oncology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the term used to describe the fact that the entire population of a neoplasm arises from a single cell that has incurred genetic change

A

clonal

all neoplastic cells are clones of the original altered cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Do cancers arise from de-differentiation of adult cells?

A

No! Adult cells do NOT go through metaplastic transformation; only primitive cells do! (aka basal cells?)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

____ tumors are designated y attached the suffix -oma

A

benign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

benign epithelial neoplasm derived from glands, although they may or may not form glandular structures

A

adenoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

benign epithelial neoplasms producing microscopically or macroscopically visible finger like or warty projections from epithelial surfaces

A

papillomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Benign epithelial neoplasms that from cystic masses such as in the ovary? cystic masses and fibrous tissue?

A

cystadenoma

cystadenofibroma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A neoplasms is termed _____ when it can invade and destroy adjacent structures and spread to distant sites (metastasis) to cause death

A

malignant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Most types of cancers (85%) are ____

A

carcinomas, most are squamous cell carcinomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Malignant neoplasms of epithelial cell origin, derived from any of the three germ layers are called _____

A

carcinomas
i.e, cancers from ectodermally derived epidermis, mesodermally derived renal tubules and endodermally derived lining of GI tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Cancer in which tumor cells resemble stratified squamous epithelium

A

sqamous cell carcinoma (most common type)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lesion in which the neoplastic epithelial cells grow in a glandular pattern.

A

adenocarcinoma

sometimes tissue or organ of origin can be identified and is added as descriptor like renal cell adenocarcinoma or bronchogenic sqamous cell carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

cancer composed of cells of unknown tissue origin is designated as _____

A

undifferentiated malignant tumor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Malignant tumors arising in solid mesenchymal tissues are called _____

A

sarcomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

malignant tumors arising from blood forming cells are called ____

A

leukemias (white blood) or lymphomas (tumors of lymphocytes/precursors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

divergent differentiation of single neoplastic clone creates a ______

A

mixed tumor (like mixed tumor of salivary gland)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What things are found within a mixed tumor?

A

epithelial components scattered within a myxoid stroma that may contain islands of cartlage or bone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

In a mixed tumor, elements arise from a single clone capable of producing both epithelial and myoepithelial cells. This is called ______

A

pleiomorphic adenoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Most mixed tumors are composed of cells from a single germ layer except what kind of mixed tumor?

A

teratoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

____ containns recognizable mature or immature cells or tissues belonging to more than one germ layer (sometimes all 3) because they arise from totipotential germ cells in ovary/testis

A

teratoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Neoplasm which differentiates prinicpally along ectodermal lines to create a cystic tumor lined by skin replete with hair, sebaceous gland, and tooth structures

A

ovarian cystic teratoma (dermoid cyst)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Are teratomas and mixed tumors malignant or benign?

A

Mixed tumors are rarely malignant, teratomas also are benign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the two general components of tissue present in BOTH malignant AND benign neoplams?

A

Parenchyma and stroma

*classification of tumors based on parenchymal component but growth and spread dependent on stroma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

_____ gives rise to neoplastic cellular component, is benign, malignant or other

A

parenchyma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

___ is the supportive cellular component (tissue skeleton upon which the parenchymal component resides); generally not neoplastic (in carcinomals) and typically consists of connective tissue (supporting framework) and blood vessels (nutrition)

A

stroma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Does the stroma contain malignant cells?

A

No but may lead to thickness called desmoblastic reaction/desmoplasia??

*some desmoplastic tumors like in female breast are stony hard called scirrhous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

polyp vs. adenoma in GI tract

A

When a neoplasm in the GI tract (benign or malignant) produces a macroscopically visible projection above a mucosal surface and projects into gastric or colonic lumen, it is called polyp; if it has glandular tissue it is called adenomatous polyp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Extent to which neoplastic parenchymal cells resemble the corresponding normal parenchymal cells, both morphologically and functionally

A

differentiation

  • 2 major determinants of differentiation are:
    1. neoplastic cells nuclei and cytoplasm and 2. architectural relationship of the neoplastic cells and non-neoplastic stroma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

lack of differentiation is called _____ and is a hallmark of malignancy; means to form backward, implying a reversal of differntiation to a more primitive level

A

anaplasia

*The less differentiated a malignant neoplasm, the more aggressive its biologic behavior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Why are benign tumors generally considered well differentiated?

A

Because they closely resemble the normal cell type and mitoses are usually rare and are of normal configuration

example: neoplastic cells in a lipoma closely resemble normal adipocytes that makes it difficult to recognize the tumor by microscopic exam of individual cells; also leiomyoma of uterus resembles normal smooth muscle cells of myometrium; thyroid adenoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

While malignant neoplasms exhibit wide range of parenchymal cell differentiation, most exhibit morphologic alterations that betray their malignant nature. Exception?

A

Thyroid anemocarcinoma—form normal appearing follicles

some squamous cell carcinomas contain cells that appear identical to normal squamous epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Grades of differentiation and clinical relevance?

A

Grade preceds second word in the phrase differentiated

  • well differentiated: closely resembles parent tissue–thyroid carcinoma and some squamous cell carcinoma (like of the skin)
  • moderately well differentiated: features of the original tissue type identifiable but not the dominant pattern, with additional atypia
  • poorly differentiated: small minority of cellular constituents allow identification of the parent tissue; cellular anaplasia
  • undifferentiated: tissue of origin cannot be discerned by histopathologic appearance of neoplasm; always associated with anaplasia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Morphological changes associated with anaplasia

A

Pleomorphism (different sized cells), abnormal nuclear morphology (nucleus to cytoplasm ratio increases–big nucleus), mitoses, loss of polarity (disorganized growth), other changes (ischemic necrosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Difference between metaplasia and dysplasia

A

metaplasia is replacment of one type of cell with another type; dysplasia literally means disordered growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Evolution of dysplasia in sqamous epithelium (difference between CIS and carcinoma)

A

When dysplastic changes are marked and involve the full thickness of the epithelium but the lesion does NOT penetrate the basement membrane its called carcinoma in situ but once the tumor cells breach the basement membrane its is called an invasive tumor (carcinoma)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Does sqamous metaplasia begin in basilar cells or adult cells?

A

BASILAR CELLS!! Never from adult cells!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Differention in squamous cell carcinoma:

  1. Well differentiated tumor cells have prominent ____ production and ____ present
  2. Moderately differentiated has a much more ___ architecture
  3. Poorly differentiated has keratin present but what?
A
  1. keratin, intercellular bridges
  2. distorted
  3. keratin ONLY detected with special techniques
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What kind of tumors (malignant or benign) retain the functions of the original cells of origin and which tumors sometimes acquire unexpected functions?

A

Benign retain function, malignant acquire unexpected functions due to derangements in differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

_____ tumors are slow growing; ____ tumors generally grow faster

A

benign, malignant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

_____ tumors are poorly circumscribed and invade surrounding normal tissue; ___ tumors are circumscribed and may have a capsule

A

malignant, benign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Tumors of mesenchymal origin:

One parenchymal cell type

A

Benign: fibroma and lipoma
Malignant: fibrosarcoma and liposarcoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Tumors of connective tissue and derivatives

One parenchymal cell type

A

Benign: chondroma and osteoma
Malignant: chondrosarcoma and osteoenic sarcoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Tumors of vessels and surface coverings

One parenchymal cell type

A

blood vessels=hemangioma (B), angiosarcoma (M)
Lymph vessels=lymphangioma (b), lymphangiosarcoma (m)
mesothelium=benign fibrous tumor, mesothelioma (m)
Brain coverings=meningioma (B), invasive meningioma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

tumors of blood cells and related cells

One parenchymal cell type

A

hematopoetic cells=leukemia (M)

Lymphoid tissue=lymphoma (M)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Tumors of muscle

One parenchymal cell type

A

smooth muscle: leiomyoma (B), leiomyosarcoma (M)

striated muscle: rhabdomyoma (B), Rhabdomyosarcoma (M)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Tumors of epithelial origin

stratified squamous

A

sqamous cell papilloma, squamous cell carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Tumors of epithelial origin

Basal cells of skin or adnexa

A

Basal cell carcinoma (malignant but never metastizes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Tumors of epithelial origin

lining of glands or ducts

A

adenoma, adenocarcinoma
papilloma, papillary carcinomas (thyroid)
cystadenoma, cystadenocarcinoma (ovaries)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Tumors of epithelial origin

respiratory passages

A

bronchial adenoma, bronchogenic carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Tumors of epithelial origin

renal epithelium

A

renal tubular adenoma, renal cell carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Tumors of epithelial origin

liver cells

A

hepatic adenoma, hepatocellular carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Urinary tract epithelium (transitional)

A

transitional cell papilloma, transitional cell carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Placental epithelium

A

hydatidiform mole, choriocarcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

testicular epithelium (germ cells)

A

seminoma (malignant; no benign form)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Tumors of epithelial origin

tumors of malocytes

A

nevus, malignant melanoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Mixed tumors–more than one neoplastic cell type but usually derived from ONE germ cell layer

A

salivary glands: pleomorphic adenoma aka mixed tumor of salivary origin (b), malignant mixed tumor of salivary gland origin (m)

renal anlage–wilms tumor (malignant)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Teratogenous–more than one neoplastic cell type derived from MORE than one germ layer–teratogenous

A

totipotential cells in gonads or embryonic rests: mature teratoma, dermoid cyst (b); immature teratoma, teratocarcinoma (m)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

One unequivocal criterion of malignancy

A

metastasis–tumor to sites physically discontinuous with primary tumor; by definition benign neoplasms do NOT metastasize

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

How do cancers spread to discontinous areas?

A

the invasiveness of cancers permits them to penetrate blood vessels, lymphatics and body cavities providing opportunity for spread. All malignant tumors can metastasize but some do so very infreqently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Metastatic cascade:

A
  1. clonal expansion, growth, diversification angiogenesis
  2. Metastatic subclone
  3. Adhesion to and invasion of basement membrane
  4. passage through EC matrix
  5. Intravasation
  6. interaction with host lymphoid cells
  7. tumor cell embolus
  8. adhesion to basement membrane
  9. extravasation
  10. metastatic deposit
  11. angiogenesis
  12. growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Sequence of events in the invasion of epithelial basement membranes by tumor cells

A

tumor cells detach from each other because of reduced adhesiveness and attract inflammatory cells. Proteases secreted from tumor cells and inflammatory cells degrade the basement membrane. Binding of tumor cells to proteolytically generated binding sites and tumor cell migration follow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Examples of cancers that invade early in their course but rarely metastasize

A

Gliomas (CNS) and basal cell carcinoma (skin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Examples of metastatic malignancies of blood forming cells?

A

Trick question! Leukemias and lymphomas are systemic circulating malignancies so the term metastatic does NOT apply!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Cancers by incidence vs. cancers by diagnosis/death in US

A

Cancers by incidence: 1. prostate/breast 2. lung 3. colon

Cancers by diagnosis/death: 1. lung 2. prostate/breast 3. colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Most common cancers in developing world

A

lung, stomach and liver in men; breat, cervix and lung in women

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

The incidence of cancer varies with geography, age, race, and genetic background. Cancers are the most common in people of what age? but occurs in adults and children of all ages. The geographic variation is due to what?

A

most common in adults older than 60

geographic variations due to different environmental exposures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Important environmental factors implicated in carcinogenesis:

A

infectious agents, smoking, alcohol, diet, obesity, reproductive history, and exposure to environmental carcinogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

what increases the risk of cancer?

A

reparative proliferations caused by chronic inflammation or tissue injury, certain forms of hyperplasia and immunodeficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Interactions between ____ and ___ may be important determinants of cancer risk

A

environmental factors and genetic factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Smoking is not only associated with lung cancer but also with what other kind of cancer?

A

AML

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Alcohol abuse is associated with what kind of cancer?

A

Hepatocellular carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Why is breast cancer risk in females that inherited BRCA1 and BRCA2 tumor suppressor genes 3x higher for women born after 1940?

A

Reproductive history changes—now women are having many more menstrual cycles because they are having less pregancies and having children later which means more opportunities for mutations during menstrual cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

Name the type of cancers associated with the following agents:

  1. arsenic
  2. abestos
  3. benzene
  4. beryllium
  5. cadmium
  6. chromium
  7. nickel
  8. radon
  9. vinyl chloride
A
  1. lung carcinoma, skin carcinoma
  2. lung, esophageal, gastric, colon, mesothelioma
  3. AML
  4. Lung carcinoma
  5. prostate carcinoma
  6. lung and oropharyngeal carcinoma
  7. lung carcinoma
  8. hepatic angiosarcoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

Acquired predisposing conditions that are related to cancer

A

chronic inflammation
precursor lesions
immunodeficiency states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

Cancer is the main cause of death among women aged 40-79 and men aged 60-79. why is the incidence of cancer higher with age?

A

accumulation of somatic mutations associated with emergence of malignant neoplasms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

_____ are the most at risk for accumulating the genetic lesions that lead to carcinogenesis

A

proliferating cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

Tumors arising in the context of chronic inflammation are usually what kind of cancers?

A

Carcinomas but also include mesothelioma and several kinds of lymphoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

Immunodeficiency states tend to predispose to what kind of cancers?

A

Virus-induced cancers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Carcinomas, the most common general category of cancer in adults are extraordinarily RARE in ____

A

Children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

When cancer occurs because of an inherited gene mutation, it is referred to as ______. Examples?

A

Heriditary cancer

Examples: mutations of BRCA1 and BRCA2 are inherited and substantially increase the risk of breast and ovarian cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

By the time a tumor comes to clinical attention (1gm or 10^9 cells), it has gone through a minimum of ____ divisions

A

30

(Likely an underestimation since many cells die via apoptosis and due to Darwinian selection of the fittest for nutrients, etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

The promiscuous tendency of tumors to become more aggressive over time due to selective pressure is called _______

A

Tumor progression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

As a tumor cell population expands, a progressively ____ percent of tumor cells leave the replicating cellular pool

A

Higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

What does the tumor evolution of a renal carcinoma tell us?

A

The mutation constituency tends to vary from the original site and even varies between metastatic sites or locales

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

One of the most profound selective pressures that cancer cells face is ________

A

Chemotherapy or radiotherapy

*tumors that recur after therapy are almost always found to be resistant if the same treatment is given again because therapy selects for pre existent subclones that by change have a genotype that allow them to survive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Genomic themes in carcinogenesis:

A

Non lethal genetic damage
Clinal expansion of single precursor cell
4 classes of regulatory genes affected: growth promoting Porto-oncogenes, growth inhibiting tumor suppressor genes, genes that regulate apoptosis, and DNA repair genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

In epigenetic modifications what determines the lineage commitment and differentiation state of both normal and neoplastic cells?

A

DNA methylation and histone modification dictates which genes are expressed which in turn determines the lineage and differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

Cell and molecular hallmarks of cancer

A
Self-sufficiency in growth signals
Insensitivity to growth-inhibitory signals
Altered cellular metabolism
Evasion of apoptosis
Limitless replicative potential
Sustained angiogenesis
Ability to invade and metastasize
Ability to evade host immune response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

Genomic instability and cancer promoting inflammation tend to ____ the features or hallmarks of cancer

A

Accelerate

98
Q

All cancers ultimately contain certain cells that are ____ and often exhibit other features related to neoplastic survival

A

Immortal

*other features: evasion of senescence, evasion of mitotic crisis, self renewal

99
Q

What are the 4 classes of regulatory genes–the principal targets of cancer causing mutations that tend to be affected in cancer?

A

Growth promoting Proto oncogenes
Growth inhibiting tumor suppressor genes, genes that regulated apoptosis, DNA repair genes

All are oncogenes if they are related to cancer development

100
Q

At least some cells in all cancers must be stem cell like. How do these cancer stem cells arise?

A

Through transformation of a normal stem cell or through acquired genetic lesions that impart a stem-like state on a more mature cell. Cancer cells acquire lesions that inactivate senescence signals and reactivate telomerase which act together to convey limitless replicative potential

101
Q

Definition of signal transduction pathway

A

A set of chemical reactions in a cell that occurs when a molecule such as a hormone attaches to a receptor on the cell membrane. The pathway is actually a cascade of biochemical reactions inside the cell that eventually reach the target molecule or reaction

102
Q

Normal cellular genes whose products promote cell proliferation

A

Proto-ocogenes

103
Q

mutated or overexpressed versions of proto-oncogenes that function autonomously, having lost dependence on normal growth promoting signals

A

Oncogenes

104
Q

a protein encoded by an oncogene that drives increased cell proliferation through one of several mechanisms

A

Oncoprotein

105
Q

Mechanisms by which oncoproteins drives increased cell proliferation:

A
  • Constitutive expression of growth factors and their receptors–>autocrine signaling loop
  • mutations in growth factor receptors like non-receptor tyrosine kinases or downstream signaling molecules that lead to constructive signaling
  • increased expression of MYC–gene needed for rapid cell growth–via chromosomal translocation a (Burkitt lymphoma), Gene amplification (neuroblastoma), increased activity of upstream signaling
  • mutations that increase the activity of cyclin-dependent kinase 4 (CDK4)/cyclin D which promote cell cycle progression
106
Q

Examples of downstream signaling molecules that lead to constitutive signaling

A
  1. Activation of EGF RTK by point mutations (lung cancer); activation of HER2 RTK by gene amplification (breast cancer); activation of JAK2 tyrosine kinase by point mutation (myeloproliferative disorders)
  2. Activation of the ABL non-RTK by chromosomal translocation and creation of BCR-ABL fusion gene (chronic myeloid nous leukemia, acute lymphoblastic leukemia)
  3. Activation of PI3K and BRAF serine/threonine kinases by point mutations
107
Q

Tumors arising in the context of chronic inflammation are usually what kind of cancers?

A

Carcinomas but also include mesothelioma and several kinds of lymphoma

108
Q

Immunodeficiency states tend to predispose to what kind of cancers?

A

Virus-induced cancers

109
Q

Carcinomas, the most common general category of cancer in adults are extraordinarily RARE in ____

A

Children

110
Q

When cancer occurs because of an inherited gene mutation, it is referred to as ______. Examples?

A

Heriditary cancer

Examples: mutations of BRCA1 and BRCA2 are inherited and substantially increase the risk of breast and ovarian cancer

111
Q

By the time a tumor comes to clinical attention (1gm or 10^9 cells), it has gone through a minimum of ____ divisions

A

30

(Likely an underestimation since many cells die via apoptosis and due to Darwinian selection of the fittest for nutrients, etc)

112
Q

The promiscuous tendency of tumors to become more aggressive over time due to selective pressure is called _______

A

Tumor progression

113
Q

As a tumor cell population expands, a progressively ____ percent of tumor cells leave the replicating cellular pool

A

Higher

114
Q

What does the tumor evolution of a renal carcinoma tell us?

A

The mutation constituency tends to vary from the original site and even varies between metastatic sites or locales

115
Q

One of the most profound selective pressures that cancer cells face is ________

A

Chemotherapy or radiotherapy

*tumors that recur after therapy are almost always found to be resistant if the same treatment is given again because therapy selects for pre existent subclones that by change have a genotype that allow them to survive

116
Q

Genomic themes in carcinogenesis:

A

Non lethal genetic damage
Clinal expansion of single precursor cell
4 classes of regulatory genes affected: growth promoting Porto-oncogenes, growth inhibiting tumor suppressor genes, genes that regulate apoptosis, and DNA repair genes

117
Q

In epigenetic modifications what determines the lineage commitment and differentiation state of both normal and neoplastic cells?

A

DNA methylation and histone modification dictates which genes are expressed which in turn determines the lineage and differentiation

118
Q

Cell and molecular hallmarks of cancer

A
Self-sufficiency in growth signals
Insensitivity to growth-inhibitory signals
Altered cellular metabolism
Evasion of apoptosis
Limitless replicative potential
Sustained angiogenesis
Ability to invade and metastasize
Ability to evade host immune response
119
Q

Genomic instability and cancer promoting inflammation tend to ____ the features or hallmarks of cancer

A

Accelerate

120
Q

All cancers ultimately contain certain cells that are ____ and often exhibit other features related to neoplastic survival

A

Immortal

*other features: evasion of senescence, evasion of mitotic crisis, self renewal

121
Q

What are the 4 classes of regulatory genes–the principal targets of cancer causing mutations that tend to be affected in cancer?

A

Growth promoting Proto oncogenes
Growth inhibiting tumor suppressor genes, genes that regulated apoptosis, DNA repair genes

All are oncogenes if they are related to cancer development

122
Q

At least some cells in all cancers must be stem cell like. How do these cancer stem cells arise?

A

Through transformation of a normal stem cell or through acquired genetic lesions that impart a stem-like state on a more mature cell. Cancer cells acquire lesions that inactivate senescence signals and reactivate telomerase which act together to convey limitless replicative potential

123
Q

Definition of signal transduction pathway

A

A set of chemical reactions in a cell that occurs when a molecule such as a hormone attaches to a receptor on the cell membrane. The pathway is actually a cascade of biochemical reactions inside the cell that eventually reach the target molecule or reaction

124
Q

Normal cellular genes whose products promote cell proliferation

A

Proto-ocogenes

125
Q

mutated or overexpressed versions of proto-oncogenes that function autonomously, having lost dependence on normal growth promoting signals

A

Oncogenes

126
Q

a protein encoded by an oncogene that drives increased cell proliferation through one of several mechanisms

A

Oncoprotein

127
Q

Mechanisms by which oncoproteins drives increased cell proliferation:

A
  • Constitutive expression of growth factors and their receptors–>autocrine signaling loop
  • mutations in growth factor receptors like non-receptor tyrosine kinases or downstream signaling molecules that lead to constructive signaling
  • increased expression of MYC–gene needed for rapid cell growth–via chromosomal translocation a (Burkitt lymphoma), Gene amplification (neuroblastoma), increased activity of upstream signaling
  • mutations that increase the activity of cyclin-dependent kinase 4 (CDK4)/cyclin D which promote cell cycle progression
128
Q

Examples of downstream signaling molecules that lead to constitutive signaling

A
  1. Activation of EGF RTK by point mutations (lung cancer); activation of HER2 RTK by gene amplification (breast cancer); activation of JAK2 tyrosine kinase by point mutation (myeloproliferative disorders)
  2. Activation of the ABL non-RTK by chromosomal translocation and creation of BCR-ABL fusion gene (chronic myeloid nous leukemia, acute lymphoblastic leukemia)
  3. Activation of PI3K and BRAF serine/threonine kinases by point mutations
129
Q

Tables 7-5 and 7-7

A

Need to know!!

130
Q

All signal transduction pathways converge on the _____

A

nucleus

131
Q

The most commonly involved nuclear regulatory proteins in human tumors?

A

MYC

132
Q

The MYC proto-oncogene is expressed in virtually all eukaryotic cells and belongs to the ______ genes which are rapidly and transiently induced by _____ signaling following growth factor stimulation of quiescent cells

A

immediate early response genes

RAS/MAPK

133
Q

Any organism whose cells contain a nucleus and other organelles enclosed within membranes

A

eukaryote

134
Q

single celled organism that lacks a membrane bound nucleus, mitochondria, or any other membrane bound organelle

A

prokaryote

135
Q

a small infectious agent that replicates only inside the living cells of other organisms. They can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea

A

virus

136
Q

activates the expression of many genes involved in cell growth; upregulates expression of telomerase; can act to reprogram somatic cells into pluripotent stem cells

A

MYC

137
Q

2 classes of MYC?

A

NMYC and LMYC

138
Q

How is MYC deregulated in cancer?

A

mutation of MYC itself and amplification in other neoplastic settings

139
Q

MYC associations with specific cancers?

A

Burkitt lymphoma, (and other B and T cell tumors), neuroblastoma, and many common carcinomas

140
Q

Burkitt lymphoma chromosomal translocation

A

chromosome 8 and 14 (MYC oncogene is translocated to chromosome 14 which normally is on 8) which then leads to increased MYC protein leading to expression of pro-growth genes

141
Q

What is the role of MYC in neuroblastoma?

A

The NMYC gene, normally present on chromosome 2p becomes amplified and is seen either as extra chromosomal double minutes or as a chromosomally integrated, homogenous staining region (HSR). The integration involves other autosomes such as 4, 9, or 13

142
Q

Name the cell cycle inhibitor: blocks the cell cycle by binding to cyclin-CDK complexes

A

CIP/KIP family

143
Q

induced by the tumor suppressor p53

A

p21, p27

144
Q

p27 responds to growth suppressors such as TGF B

A

CDK1A-C

145
Q

Familial syndromes and cancers associated with APC (mitogenic signaling pathways)

A

Familial colonic polyps and carcinomas,

sporadic: carcinomas of stomach, colon, pancreas; melanoma

146
Q

Familial syndromes and cancers associated with NF1 (mitogenic signaling pathways)

A

Familial: Neurofibromatosis type 1 (neurofibromas and malignant peripheral nerve sheath tumors)
Sporadic: neuroblastoma, juvenile myeloid leukemia

147
Q

Familial syndromes and cancers associated with NF2 (mitogenic signaling pathways)

A

Familial: Neurofibromatosis type 2 (acoustic schwannoma and meningioma)
Sporadic: meningioma

148
Q

Tumor suppressive pocket protein that binds E2F transcription factors in its hypophosphorylated state, preventing G1/S transition; also interacts with several transcription factors that regulate differentiation. What familial and sporadic cancers is this protein associated with?

A

RB
Familial retinoblastoma syndrome (retinoblastoma, osteosarcoma, other sarcomas)
Sporadic: retinoblastoma; osteosarcoma carcinomas of breast, colon, lung

149
Q

What familial and sporadic cancers is VHL associated with? (Inhibitors of pro-growth programs of metabolism and angiogenesis)

A

Familial: Von Hippel Lindau syndrome (cerebellar hemangioblastoma, retinal angioma, renal cell carcinoma)
Sporadic: Renal cell carcinoma

150
Q

What familial and sporadic cancers is CDH1 (E-cadherin) associated with? (inhibitors of invasion and metastasis)

A

Familial gastric cancer

sporadic: gastric carcinoma, lobular breast carcinoma

151
Q

What familial and sporadic cancers is TP53 associated with? (enablers of genomic stability; also a cell cycle component)

A

Familial:Li-Fraumeni syndrome (diverse cancers)
sporadic: Most human cancers

*TP 53 is the most common mutated gene and is associated with cell cycle checkpoint

152
Q

Tumor suppressor altered in majority of cancers; causes cell cycle arrest and apoptosis. Acts mainly through p21 to cause cell cycle arrest. Causes apoptosis by inducing the transcription of pro-apoptotic genes such as BAX. Levels of this are negatively regulated by MDM2 through a feedback loop. This gene? (protein?) is also required for the G1/S checkpoint and is a main component of the G2/M checkpoint

A

p53

153
Q

What familial and sporadic cancers is BRCA1 and BRCA2 associated with? (DNA repair factors)

A

Familial breast and ovarian carcinoma; carcinomas of male breast; chronic lymphocytic leukemia (BRCA2)
Sporadic: Rare!

154
Q

What familial and sporadic cancers is WT1 associated with? (unknown mechanism)

A

Familial wilms tumor

sporadic wilms tumor, certain leukemias

155
Q

Are gain of function mutations and loss of function mutations talking about the functions of the cell or the gene?

A

Gain of fnx/loss of fnx of the GENE!! NOT the cell! Gene expression NOT cellular expression!

156
Q

What are the mechanisms by which RB is abrogated in cancers?

A
  • Loss of function mutations affecting RB
  • Gene amplifications of CDK4 and cyclin D genes
  • Loss of cyclin dependent kinase inhibitors (p16/INK 4)
  • VIRAL ONCOPROTEINS THAT BIND AND INHIBIT RB (E7 PROTEIN OF HPV)
157
Q

How does RB govern the cell cycle?

A

When hypophosphorylated, RB exerts antiproliferative effects by binding and inhibiting E2F transcription factors that regulate genes required for cells to pass through the G1-S phase cell cycle checkpoint. Normal growth factor signaling leads to RB hyperphosphorylation and inactivation, thus promoting cell cycle progression

158
Q

Pathogenesis of retinoblastoma

A

Two mutations of the RB locus on chromosome 13q14 lead to neoplastic proliferation of the retinal cells. In the sporadic form, both RB mutations in the tumor-founding retinal cell are acquired. In the familial form, all somatic cells inherit one mutated copy of RB gene from a carrier parent and as a result only one additional RB mutation in retinal cell required for complete loss of RB fnx

159
Q

The role of RB in regulating the G1-S checkpoint of cell cycle

A

Hypophosphorylated RB in complex with E2F transcription factors binds to DNA, recruits chromatin remodeling factors (histone deacytelases and histone methyl transferases) and inhibits transcription of genes whose products are required for the S phase of the cell cycle. WHen RB is phosphorylated by the cyclin D-CDK4, cyclin D-CDK6, and cyclin ECDK2 complexes, it releases E2F. The latter then activates transcription of S phase genes. The phosphorylation of RB is inhibited by cyclin dependent kinase inhibitors, bc they inactivate cyclin CDK complexes. Virtually all cancer cells show dysregulation of the G1-S checkpoint as a result of mutation in one of four genes that regulate the phosporylation of RB; these genes are RB, CDK4, genes encoding cyclin D proteins and CDKN2A

160
Q

The ____ protein is the central monitor of stress in cells and can be activated by anoxia, inappropriate singaling by mutated oncoproteins, or DNA damage. It controls the expression and activity of proteins involved in cell cycle arrest, DNA repair, cellular senscence and apoptosis

A

p53

161
Q

How does p53 cause cell cycle arrest thus allowing cells to repair DNA damage?

A

DNA damage is sensed by complexes containing kinases of the ATM/ATR family; these kinases phosphorylate p53, liberating it from inhibitors such as MDM2. Active p53 then upregulated expression of proteins such as the cyclin dependent kinase inhibitor p21, thereby causing cell cycle arrest at the G1-S checkpoint allowing cells to repair DNA damage

162
Q

What does p53 do if DNA damage cannot be repaired?

A

p53 induces additional events that lead to cellular senescence or apoptosis

163
Q

Majority of human cancers demonstrate _____ mutations in TP53.

A

biallelic loss of function

*Rare patients with Li-Fraumeni syndrome inherit one defective copy of TP53 and have a very high incidence of a wide variety of cancers

164
Q

How is p53 inactivated?

A

Like RB, it is inactivated by viral oncoproteins, such as the E6 protein of HPV

165
Q

The role of p53 in maintaining integrity of genome

A

activation of normal p53 by DNA damaging agents or by hypoxia leads to ccell cycle arrest in G1 and induction of DNA repair by transcriptional upregulation of the CDKN1A (encoding CDK inhibitor p21) and the GADD45 genes. Successful repair of DNA allows cells to proceed with the cell cycle; if DNA repair falls, p53 triggers either apoptosis or senescence. In cells with loss or mutations of the p53 gene, DNA damage does NOT induce cell cycle arrest or DNA repair and genetically damaged cells proliferate, giving rise eventually to malignant neoplasms

166
Q

Mechanism of Action of tumor suppressor gene APC

A

encodes a factor that negatively regulates the WNT pathway in colonic epithelium by promoting the formation of a complex that degrades B-catenin

167
Q

In which disorders are APC mutated?

A

Mutated in familial adenomatous polyposis, autosomal dominant disorder associated with development of thousands of colonic polyps and early onset colon carcinoma; tumor development associated with loss of single normal APC allele

Mutated in 70% of sporadic colon carcinomas; tumor development associated with acquired biallelic defects in APC

168
Q

Normal APC function vs. mutated/absent APC

A

In resting colonic epithelial cells (not exposed to WNT), B catenin forms complex with APC protein which destroys B-catenin lowering levels of B cetenin. When normal colonic epithelial cells are stimulated by WNT the destruction complex is deactivated, and B catenin degradation does not occur and cytoplasmic levels increase. B-catenin translocated to nucleus where it binds to TCF, transcription factor that activates gene involved in cell cycle progression. When APC is mutated (colon cancer/polyps), the destruction of B-catenin cannot occur. B catenin translocates to nucleus and coactivates genes that promote entry into cell cycle and behave as if they are under constant stimulation by WNT pathway

169
Q

encodes a component of a ubiquitin ligase that is responsible for degradation of hypoxia induced factors (HIF), transcription factors that alter gene expression in response to hypoxia

A

VHL

170
Q

cancers associated with VHL mutation

A

Germline loss of function mutations cause von-Hippel Lindau syndrome, autosomal dominant disorder associated with high risk of renal cell carcinoma and pheochromocytoma

Acquired biallelic loss of mutations are commin in sporadic renal cell carcinoma

*CNS tumors, renal cysts, neuroendocrine tumors and renal cell carcinoma

171
Q

BCR-ABL fusion gene

A

BCR-ABL–>activation of tyrosine kinase–>activation of growth factor signaling pathways (myelogenous leukemia–translocation of chromosomes 9 and 22)

172
Q

Intrinsic and extrinsic pathways of apoptosis and mechanisms used by tumor cells to evade cell death

A
  1. Loss of p53 leading to reduced function of pro-apoptotic factors such as BAX
  2. Reduced egress of cytochrome c from mitochondria as a result of upregulation of anti-apoptotic factors such as BCL-2, BCL XL, MCL1
  3. Loss of apoptotic peptidase activating factor 1 (APAF)
  4. Upregulation of inhibitors of apoptosis (IAP)
  5. Reduced CD95 level
  6. Inactivation of death induced signaling complex
173
Q

In cancer is evasion of intrinsic or extrinsic pathway more common?

A

intrinsic–lesions that incapacitate mitochondrial pathway more common in cancers

174
Q

In greater that 85% of follicular B-cell lymphomas, the ___ gene is overexpressed due to a translocation (14 & 18)

A

anti-apoptotic gene BCL2

*overexpression of other BCL2 family members such as MCL-1 also linked to cancer cell survival and drug resistance

175
Q

RB, a negative regulator of G1/S cell cycle transition is directly or indirectly inactivated in most human cancers. RB also controls cellular differentiation. Two mutations (hits) involving both alleles of RB at chromosome locus ____ are required to produce retinoblastoma

A

13q14

176
Q

sporadic vs. familal cases of retinoblastoma

A

Familial: one defective copy already inherited (1st hit) in germline so if the normal allele of RB is spontaneously mutated somatically (2nd hit), you get retinoblastoma–autosomal dominant and can be unilateral or bilateral]

Sporadic–both copies must undergo somatic mutation–low probability

177
Q

p53 stops neoplastic transformation by inducing cell cycle arrest, senescence (cell cycle arrest), or apoptosis. p53 can also inhibit _____and its positive effects stems from its ability to function as transcription factor

A

angiogenesis

178
Q

What happens when p53 function is lost?

A

DNA damage is not repaired, mutations accumulate in oncogenes and other genes eventually leading to malignant transformation

179
Q

p53 therapeutic implications

A

Irradiation and conventional chemotheraphy mediate their effects by inducing DNA damage and subsequent apoptosis. Tumors iwth wild type TP53 alleles are more likely to be killed by such therapy than tumors with mutated TP53 alleles like in testicular teratocarcinomas and childhood acute lymphoblastic leukemias which have wild type TP53 alleles. Other tumors like lung cancers and colorectal cancers have TP53 mutations making them resistant to chemotherapy and irradiation

180
Q

Location of tumor suppressor genes is suspected by the detection of recurrent sites of _____

A

chromosomal deletions—found via high throughput sequencing of cancer genomes

181
Q

Hypoxia triggers angiogenesis through the actions of ____ on the transcription of the proangiofactor ____

A

HIF-1a, VEGF

182
Q

Other factors that regulate angiogenesis

A

p53 induces synthesis of angiogenesis inhibitor thrombospondin 1 while RAS, MYC and MAPK signaling upregulate VEGF expression and stimulate angiogenesis

183
Q

____ inhibitors are used to treat many cancers and prolong the clinical course but not curative

A

VEGF

184
Q

4 steps in ability to invade tissues, a hallmark of malignancy

A

loosening of cell-cell contacts, degradation of ECM, attachment to novel ECM components and migration of tumor cells

185
Q

In invasion, cell-cell contacts are lost by the inactivation of ____

A

E cadherin

186
Q

Basement membranes and interstitial matrix degradation is mediated by ____ secreted by tumor cells and stromal cells such as ____

A

proteolytic enzymes
MMPs

*proteolytic enzymes also release growth factors sequestered in the ECM and generate chemotactic and angiogenic gragments from cleavage of ECM glycoproteins

187
Q

The metastatic site of many tumors can be predicted by the location of the _____

A

primary tumor–many tumors arrest in the first capillary bed they encounter (lung and liver, most commonly)

188
Q

Why do some organs show tropism?

A

due to expression of adhesion or chemokine receptors whose ligands are expressed by endothelial cells at the metastatic site

189
Q

Genes that promote epithelial-mesenchymal transitions, like ____ and ____ may be important metastasis genes in epithelial tumors

A

TWIST and SNAIL

190
Q

Normally, how are tumor cells destroyed?

A

the immune system recognizes it as non-self and destroys it

191
Q

Antitumor activity is mediated by predominantly what mechansism?

A

cell-mediated mechanisms–tumor antigens are presented on the cell surface by MHC Class I molecules and are recognized by CD8+ CTLs

192
Q

The different classes of tumor antigens include what?

A

products of mutated proto-oncogenes, overexpressed or aberrantly expressed proteins, tumor antigens produced by oncogenic viruses, oncofetal antigens, altered glycolipids and glycoproteins, and cell type-specific differentiation antigens

193
Q

Immunosuppressed patients have an increased risk for cancer development. especially types caused by ____

A

oncogenic DNA viruses

194
Q

In immunocompetent patients, tumors may avoid the immune system by mechanisms including:

A

selective outgrowth of antigen-negative variants, loss or reduced expression of histocompatibility antigens, and immuno-suppression mediated by expression of certain factors (e.g, TGF BPD-1 ligand, galectins) by the tumor cells

195
Q

Proteins that are expressed at high levels on cancer cells and in normal developing (fetal) tissues. They are sufficiently specific that they can serve as markers that aid in tumor diagnosis and clinical management but they are also found at low levels in normal tissue and other inflammatory conditions

A

oncofetal antigens

196
Q

examples of oncofetal antigens?

A

CEA (carcinoembryonic antigen) and AFP (alpha-fetoprotein)

197
Q

Tumor cells expressing product of oncogene or mutated tumor suppressor gene example:

A

oncogene products: mutated RAS, BCR/ABL fusion proteins

Tumor suppressor gene products: mutated p53 protein

198
Q

Tumor cells overexpressing or aberrantly expressing self protein example:

A

Overexpressed: tyrosinase, gp100, MART in melanomas

Aberrantly expressed: cancer-testis antigens (MAGE, BAGE)

199
Q

Tumor cells expressing oncogenic virus examples:

A

Human papilloma virus, E6, E7 proteins in cervical carcinoma; EBNA proteins in EBV-induced lymphoma

200
Q

Immune cells involved in anti-tumor effector mechanisms

A

CTL, NK cells and macrophages

201
Q

Patients with ____ syndrome have defects in the mismatch repair system, leading to development of carcinomas of the colon. These patients genomes show microsatellite instability, characterized by changes in length of short repeats throughout the genome

A

HNPCC syndrome

202
Q

Patients with ____ have a defect in the nucleotide excision repair pathway and are at increased risk for the development of cancers of the skin exposed to UV light bc of an inability to repair pyrimidine dimers

A

xeroderma pigmentosa

203
Q

What syndromes are assoicated with defects in the homologous recombination DNA repair system?

A

Bloom syndrome, ataxia-telangiectasia, and Fanconi anemia that are characterized by hypersensitivity to DNA damaging agents such as ionizing radiation.

204
Q

BRCA1 and BRCA2 are genes involved in ____

A

DNA repair

205
Q

Mutations due to expression of gene products that induce genomic instability (RAG1, RAG2, AID) are important causes of ____

A

lymphoid neoplasms—affects lymphoid cells

206
Q

inflammation induced sequestration of iron and downregulation of erythropoietin production seen in some cancers

A

anemia

207
Q

In patients with advanced cancers, inflammatory reaction can be so extensive as to cause systemic signs and symptoms such as what?

A

anemia, fatigue and cachexia

208
Q

cachexia is seen in many cancer patients. Cachexia is progressive loss of body fat and lead body mass accompanied by profound weakness, anorexia, and anemia. What is cachexia associated with?

A

equal loss of both fat and lean muscle
elevated basal metabolic rate
evidence of systemic inflammation (increase in acute phase reactants)–strong association with TNF-a

209
Q

COX-2 inhibitors

A

have been shown to decrease the incidence of colonic adenomas and are now approved for treatment of paitents with familial adenomatous polyposis

210
Q

Balanced translocations contribute to carcinogenesis by? Deletions? Gene amplification?

A

-translocations: overexpression of oncogenes or generation of novel fusion proteins with altered signaling capacity.
-Deletions frequently cause loss of tumor suppressor gene function and occasionally activate proto-oncogenes.
Gene amplification generally increases expression and function of oncogenes

211
Q

Genomic sequencing has revealed numerous cryptic (subcytogenetic) rearrangements. Examples?

A

small deletions and insertions (indels) as well as chromothrypsis, in which a chromosome is shattered and then reassembled in a haphazard way

212
Q

Name the translocation and affected genes:

CML

A

(9,22); (q34,q11)
Affected genes ABL 9q34
BCR 22q11

213
Q

Name the translocation and affected genes:

AML

A

(8,21); (q22,q22)–>AML 8q22

(15,17); (q22, q21)–>ETO21q22, PML 15q22, RARA 17q21

214
Q

Name the translocation and affected genes:

Burkitt lymphoma

A

(8,14); (q24,q32)–>MYC 8q24

IGH 14q32

215
Q

Name the translocation and affected genes:

Follicular lymphoma

A

(14;18); (q32;q21)–>IGH 14q32, BCL2 18q21

216
Q

Name the translocation and affected genes:

Ewing sarcoma

A

(11,22) (q24;q12)–>FLI1 11q24, EWSR1 22q12

217
Q

Name the translocation and affected genes:

prostatic adenocarcinoma

A

(7,21) (p22q22)–>TMPRSS2 (21q22.3)

17;21) (p21;q22)–>ETV1 (7p21.2), ETV4 (17q21

218
Q

colorectal cancer progression

A
  1. Germ line or somatic mutations of cancer suppressor genes (first hit)=APC at 5q21–>mucosa at risk
  2. Methylation abnormalities, inactivation of normal alleles (second hit)=APC B-catenin–>adenomas
  3. Proto-oncogene mutation=KRAS at 12p12–>adenomas
  4. Homozygous loss of additional cancer suppressor genes (TP53 at 17p13; LOH at 18q21; SMAD 2 & 4)–>carcinoma
  5. Additional mutations, gross chromosomal alterations (telomerase, many other genes)–>carcinoma
219
Q

non-coding RNAs that do not encode proteins; instead they function primarily to modulate the translation of target mRNAs into their corresponding proteins. Posttranscriptional silencing of gene expression by miRNA is a fundamental and well conserved mechanism of gene regulation present in all eukaryotes

A

micro-RNA (miRNA)

220
Q

non-coding RNAs that modulate gene expression in many ways–for example they can bind to regions of chromatin, restricting RNA polymerase to coding genes within the region

A

lncRNAs

221
Q

Mechanism where the MICROSTRUCTURE (NOT CODE) of DNA itself or the associated chromatin proteins may be modified causing activation or silencing

A

epigenetics

222
Q

nuclei of cancer cells show abnormal morphologies like what?

A

hyperchromasia, chromatin clumping or chromatin clearing

223
Q

mutation of regulator gene MLL1 and MLL2 is related to what cancers?

A

MLL1–acute leukemia in infants (90%)
MLL2–follicular lymphoma (90%)
Both mechanisms=histone methylation

224
Q

mutation of regulator gene SNF5 is related to what cancers?

A

Malignant rhabdoid tumor (100%)

epigenetic mechanism=nucleosome positioning/chromatin remodeling

225
Q

Steps in initiation vs. promotion

*Most carcinogens require metabolic activation for conversion into ultimate carcinogens

A

Initiation: Carcinogen–>electrophilic intermediates–>binding to DNA: Adduct formation–>permanent DNA lesion:initiated cell

Promotion: –>cell proliferation: altered differentiation–>preneoplastic clone–>malignant neoplasm via additional mutations/proliferation

226
Q

People of European origin who have fair skin that repeatedly become sunburned and who live in locales recieving a great deal of sunlight (Queensland, australia, close to equator) have the highest incidence and risk for what kinds of cancer?

A

skin cancers–melanomas, squamous cell carcinomas, basal cell carcinomas

227
Q

difference between melanomas and nonmelanoma skin cancers

A

nonmelanoma=associated with total cumulative exposure to UV radiation
melanoma=associated with intense intermittent exposure (sunbathing)

228
Q

The carcinogenicity of UVB light is due to?

A

formation of pyrimidine dimers in DNA

229
Q

Radiation induced cancers by frequency:

A
myeloid leukemias (tumors of granulocytes and precursors) are most frequent followed closely by thyroid cancer but only in the young
intermediate=breast, lung and salivary gland

skin, bone and GI tract are relatively resistant to radiation induced neoplasia even through the GI epithelial cells are vulnerable to acute cell killing effects of radiation and the skin is frst in line for all external radiation

230
Q

What cancers are the following RNA viruses associated with?
HTLV-1, HPV, EBV (and burkitt lymphoma), HBV (and HCV), Merkel cell polyomavirus, HHV-8
Why isnt HIV listed here?

A
HTLV1--T cell lymphoma
HPV--cervical cancer
EBV and Burkitt lymphoma
HBV (and HCV)--hepatocellular carcinoma
HHV-8--Large B cell lymphoma and Kaposi sarcoma?
helicobacter pylori??

HIV IS NOT A TRANSFORMING VIRUS!! the rest of thes are!

231
Q

Benign and malignant neoplasms arising in endocrine glands can cause clinical problems by producing hormones. Such activity is more typical of benign or malignant tumors?

A

Benign tumors because malignant tumors may be so undifferentiated that they have lost such capablity

232
Q

*example of benign tumor that can kill you:

A

schwannoma at CPA can compress brainstem and compress respiratory centers and can kill you even though it is benign

233
Q

Endocrinopathy: hypercalcemia–major forms of underlying cancer and causal mechanisms

A

Squamous cell carcinoma of lung, breast carcinoma, renal carcinoma, adult T cell leukemia/lymphoma
Caused by parathyroid hormone related protein (PTHRP), TGFa, TNF and IL1

234
Q

Nerve and muscle syndrome: acanthosis nigricans–major forms of underlying cancer and causal mechanisms

A

Gastric carcinoma, lung carcinoma, uterine carcinoma

Causal factor: immunoloic, secretion of epidermal growth factor

235
Q

Osseous, articular and soft tissue changes: Hypertrophic osteoarthropathy and clubbing of the fingers–major forms of underlying cancer and causal mechanisms

A

Bronchogenic carcinoma, thymic neoplasms

mechanism=unknown

236
Q

progressive loss of body fat and lean body mass, accompanied by profound weakness, anorexia, and anemia, that is caused by release of factors by the tumor or host immune cells

A

cachexia

237
Q

symptom complexes in individuals with cancer that cannot be explained by tumor spread or release of hormones that are indegenous to the tumor cell of origin

A

Paraneoplastic syndromes

238
Q

Examples of paraneoplastic syndromes?

A

Endocrinopathies: cushing syndrome, hypercalcemia
Neuropathic syndromes: polymyopathy, peripheral neuropathy, neural degeneration, myasthenic syndromes
Skin disorders: (acanthosis nigricans)
skeletal and joint abnormalities (hypertrophic osteoarthritis)
Hypercoagulability: migratory thrombophlebitis, DIC, nonbacterial thrombotic endocarditis

239
Q

How are tumors graded?

A

determined by cytologic appearance; based on the idea that behavior and differentiation are related, with poorly differentiated tumors having more aggressive behavior

240
Q

How are tumors staged?

A

determined by surgical exploration or imaging–based on size local and regional lymph node spread and distant metastases; of greater clinical value than grading

241
Q

Classification of cancer according to therapeutic targets rather than cell of origin:
Lung, Breast, Prostate, colon, brain

A
lung--mutated KIT
Breast--mutated HER2
Prostate--mutated EGFR
Colon--mutated BRAF
BRain--mutated PI3K
242
Q

Know Table 7-12!!

A

slide 108