Neoplasia

Question 1

benign tumors

Answer 1

often encapsulated, surrounded by fibrous sheath of connective tissues; well-differentiated and morphology of normal cell

Question 2

malignant tumors

Answer 2

variation in size and shape, nuclear/cytoplasmic ratio and are poorly differentiated

Question 3

anaplastic

Answer 3

have lost differentiation markers

Question 4

pleomorphism

Answer 4

variation in size and shape

Question 5

hyperchromasia

Answer 5

increased DNA

Question 6

cancer development

Answer 6

normal –> hyperplasia –> dysplastic growth –> carcinoma in situ –> invasive malignancy –> metastasis

Question 7

benign

Answer 7

cells deviate only minimally from normal cells but in excessive number; hyperplasia and metaplasia

Question 8

hyperplasia

Answer 8

appear normal but with excessive number of cells

Question 9

metaplasia

Answer 9

displacement of normal cells with a normal cell type but in wrong spot

Question 10

dysplasia

Answer 10

abnormal appearance and growth rate (cancer precursor)

Question 11

carcinoma in situ

Answer 11

early form of cancer that is defined by the absence of basement membrane invasion

Question 12

invasive cancer

Answer 12

cancer cells have breached the basement membrane

Question 13

metastasis

Answer 13

cancer cells have migrated to distant sites

Question 14

oncogene

Answer 14

a gene that transforms cells; cancer-inducing

Question 15

tumor suppressor gene

Answer 15

constrains cell proliferation; loss leads to cancer

Question 16

loss of p53

Answer 16

decreased apoptosis –> cancer

Question 17

loss of APC

Answer 17

decreased cell cycle control -> cancer

Question 18

kras mutation

Answer 18

oncogene is constitutively expressed

Question 19

APC pathway

Answer 19

APC normally inhibits beta-catenin –> if lost, beta-catenin will remain on and increase proliferation and decrease differentiation

Question 20

GAP inhibition

Answer 20

GTP is always bound leading to constitutive Ras activation

Question 21

intratumor heterogeneity

Answer 21

not all cancer cells inside the same tumor have same behavior

Question 22

interpatient heterogeneity

Answer 22

same cancer in different patients but tumors are heterogeneous

Question 23

altered metabolism in cancer cells

Answer 23

will express PK-M2 to slow conversion of PEP to pyruvate, allowing glycolysis intermediates to build up and be used for NT synthesis; will express LDH for formation of lactate; take up more glucose for more energy

Question 24

initiation

Answer 24

cause DNA mutation; effect is irreversible

Question 25

promotion

Answer 25

induced by compounds (skin irritant, TPA) or endogenous conditions (hormones) that promote proliferation of cell giving rise to larger number of cells carrying mutation; NO EFFECT unless cell has been treated with initiator

Question 26

progression

Answer 26

acquisition of further mutation by exposure to initiator or repeated promoter exposure

Question 27

examples of initiator

Answer 27

cigarettes, red meat, radiation, ROS, alkylating agents

Question 28

examples of promoters

Answer 28

cytotoxic or mitogeni agents (ethanol), estrogens, androgens, chronic inflammation

Question 29

initiator only, single exposure

Answer 29

no change

Question 30

promoter only, multiple exposures

Answer 30

no change

Question 31

initiator + multiple promoters

Answer 31

papilloma

Question 32

initiator + promoter in different area

Answer 32

no change

Question 33

initiator + multiple promoters and then removal of promoter

Answer 33

papilloma regresses

Question 34

initiator + continuous promoter exposure

Answer 34

advanced papilloma, even after promoter removal

Question 35

papilloma + initiator

Answer 35

carcinoma

Question 36

Cox-2 inhibition

Answer 36

shown to suppress development of carcinoma, indicating inflammation association

Question 37

parenchyma

Answer 37

tumor classification and biological behavior

Question 38

reactive stroma

Answer 38

modulate tumor growth and spread (connective tissue, blood vessels, fibroblasts)

Question 39

invasion into distant sites

Answer 39

EMT transition for intravasation into vessels to travel to new place --> MET transition to set up colony once at new place

Question 40

EMT

Answer 40

loss of E-cadherin and catenin, gain of vimentin and fibronectin; activation of snail, slug, twist

Question 41

role of stroma in EMT

Answer 41

secretes growth factors such as EGF, HGF, TGF, FGF

Question 42

angiogenesis in cancer

Answer 42

increase in HIF-1A leads to stimulation of VEG-F to make new blood vessels

Question 43

macrophages in angiogenesis

Answer 43

produce IL-8 and VEGF and release MMPs to liberate angiogenic factors

Question 44

properties of tumor vessel

Answer 44

higher permeability, increased leakage, more dense, more fragile, not many pericytes

Question 45

avastin

Answer 45

VEGF antagonist (monoclonal antibody) to decrease angiogenesis

Question 46

sunitinib

Answer 46

VEGF receptor antagonist that inhibit receptor tyrosine kinase activities

Question 47

interferon

Answer 47

blocks IL-8 in kaposi sarcoma