Cancer-Barsky Flashcards
What does karkinos mean?
crab
What are the most common cancers for females and males?
females-> breast
males-> prostate
What are the most dangerous cancers for females and males?
lung and bronchus for both :(
What cancer has declined dramatically since the 1930s in males?
stomach cancer
What is the only cancer that has started to increase recently in males?
liver cancer!
What cancer has declined dramatically since the 1930s in females?
breast, uterine, stomach and colorectum cancer
Why do people think that some cancer deaths are decreasing?
better screaning, antibiotics
If your incidence rate for a cancer is a flat line, what does this mean?
we have shit screenings, prevention and treatments
Why was there a huge increase in incidence of prostate cancer and breast cancer?
because they got better screenings, they were always there we just didnt have a way to see them. So no cancer epidemic :)
Why would a mammogram be bad in a postmenopausal women?
cuz of radiation
WOmen should not get a pap smear until what age?
30
Cancer is a (blank) disease
genetic and epigenetic
What are the genetic causes of cancer?
- mutations, rearrangments, or amplifications involving proto-oncogenes
- reduction to homozygosity of tumor suppressor gene deletions or mutations
In addition to genetic alterations, many cancer genes are regulated (blank)
epigenetically
(blank) and (Blank) within promoters regulate gene expression of key cancer genes.
Methylation status and histone deacytylase status
Cancer is characterized by (blank) and (blank) imbalance
methyation and histone deacytylation
How do you go from a normal duct to an invasive ductal cancer?
normal duct-> intraductal hyperplasia-> intraductal hyperplasia with atypia-> intraductal carcinoma in situ-> invasive ductal cancer
Most cancers are (blank) events
multihit
Why is being a multihit event for cancer good?
promotes early detection and screening
explains why cancer is a disease of aging
Pap smears can detect (blank) before any invasion as occured.
dysplasia
where do you find blood vessels and lymphatics?
Only on the stromal side> NOT epithelial side
Are in situ cancers curable?
yes!!! because they havent escaped the epithelium so they havent gotten into the lymphatics and blood vessels. I.e. it hasnt metastasized so it can be surgically resected
Most cancers occur after the age of procreations. What does this mean for us?
that there is no evolutionary selection pressure, and that cancer is a disease of our own cells
What are the four properties of cancer?
uncontrolled growth
invasion and metastasis
clonal dominance
loss of differentiation
Is microinvasion terrible?
no, it can still be removed, but it does pose a risk
What is clonal dominance/ monoclonality?
cells of a given cancer have come from a single ancestor cell.
If tumors exhibit monoclonality how come all tumor cells are not the same?
because these monoclonal cells produce mutant subclones that are heterogeneous with respect to invasiveness, metastatic ability, antigenicity and responsiveness to chemotherapy
So explain how you can have monoclonality and heterogenity?
tumor cells all come from the same ancestor but express differently due to mutations
What are the four types of cancer therapies?
surgery
radiotherapy
chemotherapy
immunotherapy
What are limitations in treating cancer?
lack of a tumor specific antigen
tumor cell heterogeneity
micrometastasis
What are the causes of human cancer?
environmental carcinogens UV radiation other ionizing radiation viruses lifestyle diet immune status hereditary factors or genes unknown
What makes a chemical carcinogen direct or indirect?
cytochrome P450
What are the chemical carcinogens?
eletrophiles,
initiatiors and promotors
What is this:
acts by forming DNA adducts which give rise to mutations
initiators
initiators tend to be (neutrophiles/electrophiles)?
electrophiles
What is a DNA adduct?
when carcinogens bind to DNA
What regulates chemical carcinogens?
Phase I and Phase II enzymes
How do chemical carcinogens work?
acts by forming DNA adducts which give rise to mutations; if mutations occur in hot spots, spots which change gene expression or protein, mutations can be carcinogenic; if mutations occur in introns or junk DNA or in the non-coding strang they can be harmless.
What is the action of UV radiation and other ionizing radiation?
formation of DNA adduts but can cause single and double strand DNA breaks
What does ionizing an UV radiation do?
causes chromosome breakage, translocations and point mutations
What does UV radiation lead to?
skin cancer
Who are at increased risk for skin cancer?
xeroderma pigmentosum
What happens to children with radiation exposure?
thyroid cancer
How many types of HPV are there?
80+
What strains of HPV causes papillomas or warts?
1,2,4,7
What strains of HPV are in almost 100% of invasive squamos cell carcinoma and carcinoma in-situ (CIS) of cervix?
16 and 18
What strains of HPV have low malignant potential?
6 and 11
How does HPV cause malignancy?
early gene products E6 and E7 inactivates tumor suppressor genes TP53 and RB, respectively
**full malignant potential requires other environmental factors*
What four tumors is EBV associated with?
Burkitt’s lymphoma
B cell lymphomas
Hodgkins disease
Nasopharyngeal cancer
Where is nasopharyngeal cancer endemic?
So. China
What is this:
cell proliferation with decreased immunoregulation
all associated with t(8:14) - MYC gene
nonendemic area only 20% have EBV
Burkitt’s lymphoma
What is hepatocellular cancer associated with?
Hep B virus
What is the greatest association with cancer?
Hep B
How does Hep B virus contribute to the incidence of hepatocellular cancer?
Injury and regeneration predispose to mutations with environmental agents
AND hepB protein disrupts growth control by activating protooncogenes, may inactivate TP53
Why does immunodeficiency accelerate viral cancers and not other cancers?
because viruses cause an antigenicity that the immune system can attack and with immune compromise your viral cancer wil accel. Breast cancer or something does cause an immune response so lack of immunity wont change the tumor.
(blank) hosts have a higher rate of certain cancers like lymphoma and virally-induced cancers.
immunodeficient
T or F
women who are nulliparious have a high rate of breast cancer
T
Men who are obese have a higher rate of cancer of the (blank)
esophagus
Women who eat fatty foods have a higher rate of (blank) cancer
breast
Men who drink alcohol and smoke have a higher rate of (blank) and (blank) cancer
head and neck
People who eat red meat have a higher incidence of (blank) cancer
colon
T or F
Many cancers have a familiar component; fewer cancers have an inherited component
T
T or F
some cancers are familial with genes not identified
T
T or F
some cancers are inherited (germline) with gene identified
T
What is Li-Fraumeni syndrome?
What does it cause and how do you get it?
Li-Fraumeni syndrome-1 is caused by heterozygous mutation in the p53 gene
-a hereditary disease that causes many kinds of cancers
What does BRCA1 and BRAC2 do?
they are genese associated with breast cancer
(blank), often called hereditary nonpolyposis colorectal cancer (HNPCC), is an inherited disorder that increases the risk of many types of cancer, particularly cancers of the colon (large intestine) and rectum, which are collectively referred to as colorectal cancer.
Lynch syndrome
(blank) is the condition of genetic hypermutability that results from impaired DNA Mismatch Repair (MMR)
Microsatellite instability (MSI)