Cancer study guide- Mini exam 4 (09/15) Flashcards
What factors contribute to risk of cancer? Is it genetic?
cancer is multifactorial and hereditary; environmental factors, cell cycle, and genetics
Explain the environmental factors that contribute to risk of cancer
Viruses (HPV), Tobacco smoke (causes chronic inflammation), Food (aspertain in drinks, nitrates in processed foods, grilling), Radiation, Chemicals, and Pollution (respiratory cancer)
what are the different genes associated with cancer
oncogenes, tumor repressor genes, and DNA repair genes (AKA caretaker genes)
how are oncogenes created and what do they do? What does this mutation cause?
promote self-regulated and normal cellular growth; in their normal state, oncogenes are called protocol-oncogenes or anti-oncogenes, when mutated into oncogenes, cellular growth is unregulated, causing tumor growth,
what is the job of tumor suppressor genes? what happens if they are mutated?
regulate cell division in the midst of oncogenes (so if the anti-oncogenes are compromised, this is plan B); these are found in two spots in the chromosomal makeup, so the first mutation is usually inherited, but can also be somatic and the other is the major even, usually environmental, if mutated cell division is no longer regulated
DNA repair genes do what normally? What happens when they are mutated
detect a mutation and promote the repair of that action in the cell cycle to ensure that future cells will be normal; normally sends protein to the site mutation to repair, mutations will cause a slow reaction or cause genes to become dormant
What is proliferation?
the generation of new, daughter cells divided from progenitor cells (parents) - think of parents letting their kid go off to college/start their career
What specific cells play an important role here?
stem cells plan an important role because they don’t have a specific function when they are first produced
explain the properties of stem cells
highly undifferentiated, have potential to divide into daughter stem cells, can mature into more differentiated units that have a specific function, but must be put in the right enviornment for this
what is cellular differentiation
the maturity, specificity, and functionality of cells; an orderly process
list the steps of differentiation
- cells start out as undifferentiated stem cells (potential to mature/become more specific, but again its all about the environment)
- as a need arises, the stem cells turn into progenitor (parent) cells that can produce daughter cells, allowing the progenitors to mature and have a specific function
- daughter cells then become highly differentiated and cannot reproduce
what is ideal when looking at cellular differentiation in patients
we want tissue cells to like the surrounding tissue, which means they are still well differentiated. When they do not, they have become undifferentiated
what are the three most frequent problems with cell differentiation
- over proliferation (production of daughter cells/stem cells): proto-oncogenes become oncogenes, tumor repressor cells are mutated and cannot stop/regulate growth and DNA repair genes no longer recognize/fix mutations
- lack of differentiation
- neoplasia-irreversible deviant development of cells that can result in the formation of neoplasms (tumors)
where can neoplasia occur
only in cells that have the ability to proliferate (lots of reproducing/growing); examples of this are skin, GI tract, and respiratory tract
where can neoplasia not occur
cannot occur in cell structures that are permeant because they are not proliferation. Examples include cardiac myocytes, mature neurons (neuroblastoma is almost always in children because adults are not producing these anymore), and the lens of the eye
list and explain the characteristics of neoplastic cells (neoplasms)
autonomy, anaplasia, lack cell-to-cell inhibitions, cohesions
angiogenesis
adhesiveness, energy dependent
autonomy
unregulated cell growth, independent cells
anaplasia
describes the neoplasm’s loss of differentiation, the neoplasms no longer look like the tissue of origin because of the lack of differentiation
cell-to-cell inhibitions
knowing when to stop growing
cohesion
staying together
adhesiveness
stickiness
energy dependent
suck away nutrients from other places to provide for own growth
angiogenesisi
develops new blood vessels to promote new growth, deprive unaffected tissues of oxygen and other nutrients (killing surrounding tissues), this can create inflammation, which then causes edema, can also cause secretion of substances that alter the metabolic processes
explain cancer at the cellular level
at the cellular level, cancer is genetic. All cancer comes from a malfunction of the genes that turn controls protons-oncogenes, tumor suppressor genes, and DNA repair genes/caretaker genes
what are the four steps that outline cancer occurrence
- reproduction
- growth
- differentiaton
- death
what are carcinogens and how do they work
cancer-causing agent that interferes with the molecular pathways and can initiate or promote tumors to form in the body
explain the 4 steps of carcinogenesis
- initiating event: irreversible change of DNA, can be stopped
- promoters (internal and external): cause further changes to DNA; internal is hormones, external is smoking, food, etc
- continued exposure and change in the DNA: this results in a malignant tumor
- progression of metals: can spread to other parts of the body
explain the differences in characteristics between benign and malignant tumors (cell differentiation)
- benign: similar to normal cells, does not have significant loss of differentiation, mitosis fairly normal
- malignant: vary in shapes and size, large nuclei, many undifferentiated, mitosis is increased and atypical
explain the differences in characteristics between benign and malignant tumors (encapsulated)
- benign: encapsulated and expands, but does not spread
- malignant: no capsule
explain the differences in characteristics between benign and malignant tumors (growth rate)
- benign: relatively slow, expanding mass
- malignant: rapid growth, cells do not adhesive, infiltrate tissues
explain the differences in characteristics between benign and malignant tumors (location)
- benign: remain localized to where it started growth
- malignant: can spread
explain the differences in characteristics between benign and malignant tumors (recurrence after removal)
- benign: rare
- malignant: tumors spread, recurrence is more common
explain the differences in characteristics between benign and malignant tumors (others)
- benign: can still be life threatening, in the brain it can compress the brain and can cause loss of function, sometimes a precursor to cancer
- malignant: extremely invasive and aggressive, does not resemble tissue of origin, can cause ischemia (lack of O2 and nutrients) and necrosis of tissue (cell death)
name several systemic effects of malignant tumors
- cachexia-general illness and malnutrition (can include weight loss, wasting of muscle, fatigue, loss of appetite, etc.)
- anemia due to blood loss at the site
- nutritional defects that reduce hemoglobin synthesis
- effusions-escape of fluid
- infection
- bleeding
- erosion of blood vessels
- paraneoplastic syndrome (biochemical disturbances)
- tumors can release substances that affect neurologic function and may have hormonal effects
- psychological factors
what can proliferation within the tissue of origin cause
obstruction, hemorrhage (bleeding), necrosis, better prognosis
explain invasion/direct extension and what it does
tumor cells move and grow into adjacent tissues/organs as well as nearby structures; this releases enzymes that degrade tissue walls and allow the tumor to grow
what is seeding and where does it occur
cancer cells growing in the body fluids or along membranes; occurs many times within the peritoneal or pleural cavities surrounding affected organs/tissues; gravity pulls cells downward or cells will follow flow of fluid within the body cavity
what is metals
malignant neoplasms (cancer cells) use blood vessels to spread to distant sites; easier for the cancer to get to in via lymphatic system; detection and treatment become more complex if this occurs (if metastasis is present, the cancer is stage four)
explain the four steps of metastasis
- Breaks: breaks through the basement membrane and/or extracellular membrane
- Gains: gains access to and begins to circulate within the blood vessels or lymph system
- Leaves and adheres: leaves the blood vessels/lymph system and adheres to distant tissues
- New network: establishes a new nutrient network through the process of angiogenesis
define organ tropism
desire of a primary tumor to relocate to a specific distant site
Factors include:
-favorable environment
-increased adherence capability
-location in relation to blood/lymphatic flow
three examples of organ tropism
- colon cancer to the liver
- lung to the brain
- breast or prostate to bone
what is the acronym for cancer classifications and what does each stand for
TNM
T: size of tumor
N: involvement in the lymph system
M: metastasis 9remember, if this one is yes, it is immediately stage 4)
the grades of cancer
Grade 1: well differentiated, cancer confined to one organ of origin
Grade 2: moderatley differentiated, cells invading, but locally
Grade 3: poorly differentiated, spread to regional structures
Grade 4: undifferentiated, spread to distant sites
-oma
means benign tumor
ex: lymphoma (lymphatic tissue) and glioma (nervous system)
-carcinoma
cancerous
ex: adenocarcinoma (glandular tissue), sarcoma ( connective, always cancerous)
carcinoma-in-situ
early stage cancer that has not broken through basement membrane of the organ
leukemia-hematopoietic
blood forming organs
what does the acronym CAUTION stand for
Change in bowel/bladder A lesion that does not heal Unusual bleeding or discharge Thickening or lump in breast or elsewhere Obvious change in wart or mole Nagging cough or persistent hoarseness
four examples of risk factors for cancer
chronic irritation and inflammation
age
diet
hormones
Your patient has a history of various types of cancer in her family history. What are some ways she can reduce her risk
limit UV exposure, self-examinations, diet-increase fiber, reduce fat, regular medical exams
explain immunity’s role in cancer
cell-mediated immunity can recognize some tumor cells and destroy them (natural killers), immunization (artificial) or cervical cancer and HPV
Thrombocytopenia
Platelets, low platelets means increased risk for bleeding/hemorrhage, always watching for nosebleeds, brush teeth differently, electric razor
neoplasia
growth of a tumor
neoplasm
is the tumor/cancerous cells
