Bio 235 Exam 3 Cancer

tumor suppressor proteins, encoded by tumor suppressor genes:

-loss or inactivation of just one can lead to cancer -few dozen proteins in entire proteome -fusion of normal cells to cancer cell yields hybrid that usually does not show cancer

_____ causes _____ cancer, but not if injected into the _____ directly, has to be acted upon by body's metabolism first

2-napthylamine, bladder, bladder

more than ___ human ______ identified

200, oncogenes

HeLa cells

20K divisions, derived from uterine cervical cancer

Hayflick limit

50-60 cell divisions

about _____ of cancer deaths due to dangerous spreading, rather than the growth of _____ _____

90%, primary tumor

Fibroblast Growth Factor (FGF)

A peptide growth factor, originally defined by its mitogenic effects on fibroblasts; also acts as an inducer during early brain development.

_____ _____ shows mutagenic potential of chemicals using microbes, chemicals may bind DNA directly. Necessary to react chemical with ____ _____ in ____ _____

Ames test, liver extract, Ames test

CHO

Chinese hamster ovary

cancer cells are unresponsive to_____

DNA damage as normal cells are

___ ______ can cause cancer, such as forming wrong bonds between bases, bonds being broken, bases removed, etc

DNA modification

cancer cells downregulate proteins like _____ _____ that is needed to keep cells _____ to each other

E-cadherin, attach

Burkitt's lymphoma

Epstein-Barr virus

Retinoblastoma controls cell cycle progression from __ to _ (at restriction point), important in many cancers

G1, S

___ produces __ protein, targets _____

HPV, E7, retinoblastoma

___ causes cancer (___ 16, 18, others), ___ vaccine prevents cancer, ___ 18 found inserted into genome of ___ cells

HPV, HPV, HPV, HeLa

Telomeres

Repeated DNA sequences at the ends of eukaryotic chromosomes.

insertional mutagenesis

Retroviruses integrate at random locations in the genome. Retroviral insertion can disrupt gene function or proper regulation of nearby genes.

What did Peyton Rous discover?

Rouse Sarcoma virus, caused cancer in chickens, this is an oncovirus (Nobel Prize over 50 years later)

some normal cells inhibit cancer cells by secreting _____ (controls proliferation through cell cycle and apoptosis). Some cancers are not resistant to this. Some cancer cells produce _____ themselves to inhibit growth of normal cells

TGFB, TGFB

"seed and soil" hypothesis

The metastases can only form in compatible microenvironments. This is why some cancers tend to lead to classic metastases.

ionizing radiation

X ray, radioisotopes (Chernobyl, radium, radon, etc), UV light

E-cadherin

a cell adhesion molecule that is expressed in normal breast tissue

what is portal vein?

a vein conveying blood to the liver from the spleen, stomach, pancreas, and intestines.

tumor cells show

anchorage-independent growth

some tumors downregulate compounds such as _____ that restricts vessel growth, showing another mechanism tumors evolved to support their growth

angiostatin

BHK 21

baby hamster kidney

prostate cancer often metastasizes to _____ because _____ cells produce molecular factors stimulating prostate cell growth, irrespective of _____ _____ _____

bone, bone, blood flow patterns

if both cells resulting from split retain ability to divide, then _______ can result

cancer

malignant

cancerous

"_____ _____" is making compound more likely to cause cancer following chemical modification

carcinogen activation

_____ causes cancer, but ______ must be acted upon by action of liver to cause cancer

carcinogens, procarcinogens

Autophagy

cell breaks down and destroys old, damaged, or abnormal proteins in cytoplasm

disruptions in _____ _____, pay attention to _____ _____

cell cycle, restriction site

hybridoma

cells formed via fusion between a short-lived antibody-producing B cell and an immortal myeloma cell

upregulation of cells response to _____ leads to _____ mobility of _____ cancer cells

chemoattractant, increase, metastatic

initiation

conversion of normal to precancerous cell such as coal tar components, permanent mutation

_____ ___ oxidizes compounds in blood, usually making _____ toxic

cytochrome P450, less

tumor progression

differentiation of cell usually becoming more aggressive, Darwinian selection, heterogeneous populations, clonal expansion, increasing number of mutations and epigenetic changes

in tumor, cell _______ and cell death

division is uncoupled from cell differentiation

_____: studies have shown cancer rates differ _____, not usually by ethnic background

environment, geographically

Carcinoma

epithelial

what do oncogenes involve in

excessive amount of molecule, abnormal function of molecule

angiogenesis

feeds blood to tumor as it grows

what are examples of growth signaling components

growth factors, receptors, GTP-binding proteins, nonreceptor kinases, transcription factors, cell cycle and apoptosis regulators

overcoming requirements for _____ _____, by short circuiting _____ _____ mechanisms, including defects in signal transduction

growth factors, surface receptor

Rag2 knockout mice

have no functional lymphocytes, and develop more tumors, immune system more effective vs virus-induced cancers

_______ detect binding, if none destruction by _______ (as opposed to _______)

integrins, apoptosis, necrosis

what are the three steps of metastasis

invade tissue to access blood or lymph, travel in fluid system, and leave fluid system, grow in remote tissue or organ

metastasis

invades bloodstream and travels

what are two mechanisms of cell spreading

invasion, metastasis

cancer cells block pathways _____

leading to apoptosis, and this can be the actual mechanism of cancer in some cell types

tumors must "_____" not to produce _____ _____

learn, foreign antigens

_____: (such as smoking or working as a chimney sweep) affect cancer rates

lifestyle

A549 cells

lung, adenocarcinoma cell in human (secretory capacity in epithelial cancer)

what another location common for metastatic activity

lungs, liver, stomach, intestines

lymphoma

lymphatic tissue, solid tumors

cancer cells invade _____ system, becoming lodged in _____ _____, common location for _____ _____

lymphatic, lymph node, metastatic tumors

point mutation

many (up to 30%) human cancers from mutation of Ras (small monomeric G protein)

tumor (neoplasm)

mass of cells growing without normal control, but not always growing faster than normal tissue

what cells seed new organs to continue cycle?

metastatic cells

benign

mild, not cancerous

what doe metastatic tumors release?

millions of cells per day into blood or lymph

transit amplifying stem cell

more differentiated, but keeps opportunity to divide

L cells

mouse fibroblast

chromosome translocation

movement to more of less expression

J774

murine macrophage cell line

______ is important in developing cancer

mutation

basal layer of skin has cells that when dividing____

one cell keeps division option, stem cell one cell gives up cell division and makes keratin

gene amplification

over expression

_____, crucial regulating molecule for cell division

p53

___ can be damaged by some compounds in smoke (___ controls cell cycle, guardian of genome)

p53, p53

___ is most frequently mutated protein in human cancers, ___ triggers cell cycle arrest, apoptosis, and DNA repair mechanisms

p53, p53

invasion

penetration of tissue

what is perinuclear halo

presence of a vacuolated area that surrounds the nucleus

ability to _____ and _____ causes cancer

proliferate, move

uncontrolled _____ is defining for cancer, but _____ __ _____ is also crucial for disease

proliferation (rapid increase of numbers), ability to spread

some cancer cells increase production of _____ (like _____) needed to erode tissue (like _____ _____ adjacent to epithelial cells) to facilitate penetration and migration

proteases, plasmin, basal lamina

_____ are normal, but can be dysregulated (to oncogenes) and cause cancer or can be brought into cell by virus. _____ cell proliferation, _____ cell survival

proto-oncogenes, increased, increased

_____ must be converted to _____ to become _____

proto-oncogenes, oncogenes, carcinogenic

promotion

repeated exposure to certain triggers such as croton oil that contains phorbol esters, hormones or growth factors

immune surveillance theory:

restricts growth of tumors cells, suggests tumors are common but body seeks and destroys them, immune suppressed patients have more cancers

first tumor suppressor gene

retinoblastoma (RB) gene, found in family with trait

density-dependent inhibition of growth

seen in cell culture systems in the lab

experiments with nude mice

showed ability to implant tumors, these lack a functional immune system bc no thymus or T immune cells (no adaptive immune response)

cancer cells die at all points of the cycle...

showing they were not halted at restriction point

two-hit hypothesis

since we have two genes, may require two mutations ("Sully" and flt 1549)

what is a koliocyte

specific cellular events caused by infection with HPV

Vascular endothelial growth factor (VEGF)

stimulates angiogenesis from existing vessels

What is helicobacter pylori?

stomach cancer

epidemiology

study of causes of disease

sarcoma

supporting, tissue, cartilage, fat, bone, muscle

maintenance of _____, expression of _____, important in development of cancer

telomeres, telomerases

What can UV light cause?

thymidine dimers, leaves signature of sunlight damage in p53 gene found in skin exposed to sun, simply sign of damaged or cause of cancer

_____ and _____ tumors selects for cells more capable of being metastatic

transport, re-establishing

local DNA rearrangement

two genes can be combines, Philadelphia chromosomes

cell differentiation (senescence)

usually limit cell division capacity

cancer cells produce _____ and _____ stimulate vessel growth

vascular endothelial growth factors, fibroblast growth factor

Hepatitis B and C

virus causes liver cancer

leukemia

white blood cells in general, fluid tumors