exam 3 neoplasia part 2

Question 1

Answer 1

cell cycle

Question 2

What is the MDx of this neoplasm if it is malignant and involves sqaumous cells?

Answer 2

squamous cell carninoma

Question 3

Answer 3

All

Question 4

Oncogene mutations are dominant meaning ???

Answer 4

only need one to gain function uncontrolled growth

Question 5

A mutation with what gene is present in 20% cases of dogs with mast cell tumors

Answer 5

ckit

Question 6

_____ is the result of certain heritable changes in the DNA of tumor cells.

Answer 6

neoplasia

Question 7

4 types of abnormalities that can lead to neoplasia

Answer 7

defective DNA repair

self suffiecient growth signals

insensitivity to growth inhibition signals

evasion of apoptosis

Question 8

Tumor suppresor genes are ___ meaning the need 2 independent mutations to occur for cells to not be sensitized to growth inhibition signals

Answer 8

recessive

Question 9

p53 is an example of a ___

Answer 9

tumor suppressor gene

Question 10

Most common mutation is human neoplasm

Answer 10

mutation with p53 because we only have 1 copy

Question 11

Elephants have less instances of cancer than people because???

Answer 11

they have more copies of p53

Question 12

Answer 12

D

Question 13

Question 14

Tumor is intially made from clonal daughter cells of the first mutted cell. Then more mutations are aquired as genetic instability increases. Malignant cells being treated with chemo/radiation pose what risk if you dont kill all cancer cells?

Answer 14

selective for malignany that is resistent to treatment

Question 15

Malignant tumor on spleen with an endothelial origin. Whats MDx?

Answer 15

splenic hemangiosarcoma

Question 16

Malignant metastisis to the lungs of an endothelial origin. Mdx?

Answer 16

pulmonary metastatic hemangiosarcoma

Question 17

Adult white cat presents with thickened firm crusty erosion on nose. Predisposition for what cancer in situ?

Answer 17

squamous cell carcinoma in situ

Question 18

Which is squamous cell carcinoma in situ and which is squamous cell carcinoma? How can you tell?

Answer 18

L = in situ

R= malignant

It has more cell types (mutations and it is invasive)

Question 19

This invasion is characteristic of what type of metastisis mutation characterized by cells not respecting anatomical borders

Answer 19

loss of contact inhibition

Question 20

What are the four stages of migration leading to metastisis.

Answer 20

1) loosen cell jxn decreased expression of cadherins
2) degradation by cleavage of matrix components
3) attachment increased expression of laminin, collagen, fibronectin receptors
4) growth factors follow chemotaxis

Question 21

This is a histopath of an adult cat mammary tumor. Regarding this tumor, which is/are true:

A. It is a carcinoma

B. It could be benign

C. It has metastasized

D. None are true

Answer 21

it is a carcinoma more likely malignant than a similar tumor in a dog, invaded into the blood vessel not metastisized

Question 22

What is the difference between normal angiogenisis and tumor angiogenisis?

Answer 22

Vascular endothelial growth factor meshwork and leaky

Question 23

What are the three types of spreading for metastisis neoplasms?

Answer 23

transcolemic

hematogenous

lymphatics

Question 24

What type of cancers favor hematogenous spread?

Answer 24

sarcomas

Question 25

What type of cancers favor lymphatics?

Answer 25

carcinomas

Question 26

Hematogenous and lymphatic spread neoplasms arrest in the first capillary bed encountered. For many tumors this is in the ____, but for enteric tumors this is the ____

Answer 26

lung

liver

Question 27

term for bone metastisis occuring with mammary and prostate carcinomas.

Answer 27

organotropism

Question 28

pulmonary carcinomas often metastisize in the ___ of a cat

Answer 28

digit

Question 29

Answer 29

yes spontaneous regression of histyocytoma by lymphocyte attack

Question 30

Immune system is capable of recognizing self-antigens expressed on tumor cells and attacking these cells

Answer 30

immunesurveilance

Question 31

4 ways neoplasms can evade the immune system

Answer 31

1. Altered MHC expression
2. Loss or masking of tumor-specific antigens
3. Tolerance – especially if the antigen is shared with normal tissues
4. Immunosuppression – Fas ligand stimulates apoptosis of binding T cells

Question 32

3 mechanisms of altering DNA

Answer 32