Tumor Immunology

Question 1

What is cancer?

Answer 1

A diverse collection of diseases that result from abnormal and invasive cell proliferation; they are very similar to normal cells so the immune system cannot effectively “see” them as foreign

Question 2

How does cancer arise?

Answer 2

Mutations of somatic cell DNA

Question 3

What is a tumor?

Answer 3

Tissue in which cells are multiplying abnormally

Question 4

What is metastasis?

Answer 4

Spreading of tumor cells through lymph or blood

Question 5

What are carcinomas?

Answer 5

Cancers of epithelial cells

Question 6

What are sarcomas?

Answer 6

Cancers of other cells

Question 7

What are the cancers of the immune system?

Answer 7

Leukemias: involving circulating cells
Lymphomas: involving solid lymphoid tumors
Myelomas: involving bone marrow

Question 8

Exposure to what initiates cancer?

Answer 8

To chemicals, radiation, and viruses; carcinogens (mutagenic agents)

Question 9

HPV leads to what type of benign and metastatic cancer? (DNA Virus)

Answer 9

Warts (benign); Carcinoma of the uterine cervix

Question 10

Hepatitis B leads to what kind of cancer? (DNA Virus)

Answer 10

Liver cancer (hepatocellular carcinoma)

Question 11

Epstein-Barr virus (EBV) leads to what kind of cancer? (DNA Virus)

Answer 11

Burkitt’s lymphoma (cancer of B lymphocytes), Nasopharyngeal cancer, B-cell lymphoproliverative disease

Question 12

Human T-cell leukemia virus type 1 leads to what kind of cancer? (RNA virus)

Answer 12

Adult T-cell leukemia/lymphoma

Question 13

HIV-1 and HHV8 lead to what kind of cancer?

Answer 13

Kaposi’s sarcoma

Question 14

Some tumors express what that can be recognized by the immune system?

Answer 14

Tumor specific antigens (TSA’s); different tumors express different TSA’s

Question 15

Tumors arise from? 2 things

Answer 15

1) Reactivation of embryonic genes not normally active in the cell
2) Over-expression of normal self-proteins which changes density of self-peptide presentation leading to recognition by T-Cells

Question 16

What happens if you inject tumor cells from an MHC_A mouse into an MHC_B mouse?

Answer 16

Tumor cells are rejected and the mouse lives

Question 17

How can tumor cells evade immune responses?

Answer 17

They mutate so they are not recognized; between 1/3 and 1/2 have defects in expression of HLA class 1 allotropes

Question 18

What cells are both involved in immunity to tumors?

Answer 18

CTL’s and NK cells

Question 19

What do tumors produce to create an immunosuppressive environment around the cell?

Answer 19

Cytokines (such as TGF-beta)

Question 20

Tumor targeting is done using what?

Answer 20

Humanized monoclonal antibodies (hmAbs)

Question 21

How can humanized monoclonal antibodies be used?

Answer 21

Diagnostics
Treatments; hmAbs used as ligand agonists or antagonists, or conjugated to toxins or radionucleotides for targeted killing of tumor cells

Question 22

What are the two ways cancer cells can be targeted?

Answer 22

Toxin binds and enters nucleus = apoptosis

Drugs radioactively bind to cells, radiation damages cells and kills them