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T cells respond to foreign MHC and become activated
Something about t cell receptor recognizes it and T cells become activated.


Describe cancer cells and what causes them to be that way

Cancer cells are self cells; altered self cells due to mutations


Describe cell cycle of cancer cells

lack apoptosis
mutation in p53
telomerase is active... repairs cancer cells so they don't die
cancer cells are also malignant (spread to other areas of the body)


Describe the chemical, physical, and biological agents associated with causing cancer

Other things can lead to cancer
Chemical: nitrates, nicotine, asbestos
Physical: radiation and UV light
Biological: other viruses such as HPV, EBV, HTL-V


role of cmyc

want the cell to divide- c myc turned on
want cell to rest- turned off


Burkitt's lymphoma

B cell tumor
when c- myc is moved to IgH gene enhancer


Why is the immune system not always able to destroy cancer cells?

We know that immune system does play some role because those who are immunosuppressed have a greater chance at developing cancer

different things can alter the DNA/ cells/ proteins to make body see them as foreign (Ex: melanoma caused by UV radiation can alter proteins causing body to fight against own proteins)

since some cells are host dervived they may not be recognized as antigen

TILs alo recognize the antigen and come to it but something suppresses the t cell and it is unable to respond


Tumor Antigens

used to induce an immune response
can be tumor specific (rare)
tumor associated (more common)


Tumor Antigens I

TSTA: unique to tumor cells/ not on normal cells (difficult to find) (HPV)

TATA: not unique; proteins found at different developmental stages; proteins expressed much higher on cancer cells


Tumor Antigens II (oncofetal)

CEA: found on colon cancers
AFP:liver and germ cell tissues; increased in hepatitis; after tumor therapy iincrease= relapse


Tumor Antigens III

expressed and presented with MHC 1
some viral proteins cause abnormal regulation of cell
Oncogenes: abnormal
Protooncogenes: normal but mutated causing cancer


examples of tumor antigens that can be used for detection of tumor growth

HPV- viral- cervical carcinoma- ncoviral
Surface immunoglobin- gene arrangements with B cell- lymphoma- differentiation


If tumor antigens, why no immune response?

lack of antigenic epitope
decreased MHC expression
lack of co simulation (n B7)
Production of inhibitory substances
shedding of tumor antigens


CAncer Therapy

Conventional: surgery, radiation, chemotherapy drug treatment

Passive:monoantibody against tumor specific antigens
Ab- to Fas= apotosis
prevent angiogenisis: blocking blood supply to cancer

TILs : isolate them; inject with IL-2 and give back in pt.
DCs with tumor antigen
Bone Marrow Transplant (lymphoid origin)
cytokines (IL-2; INF alpha)



typical marker for B cell cancer