L12 Cancer and the Immune System & Immunotherapy Flashcards
does an individual need one or two copies of the gene to be knocked out from birth in order to be at higher risk for cancer?
two copies need to be knocked out as there are normally two copies, if one copy is present it can ‘compensate’ if one copy is knocked out.
% cancers caused by environmental factors?
approximately 80%
What are Mut-driver genes?
These are genes that contribute to cancer
What is a driver mutation?
A change in a gene/protein that gives a cancer cell a fundamental growth advantage for its neoplastic transformation.
Define cancer:
malignant transformation of cells
Where do carcinomas arise from?
From the endoderm and ectoderm
Carcinomas are epithelial cell cancers
Give an example of a carcinoma
- Breast cancer
- Colon cancer
What is leukaemia?
Leukaemia is cancer of the blood or bone marrow, involving the abnormal increase of immature white blood cells called ‘blasts’
What is lymphoma?
A tumour in lymphoid tissue, bone marrow, lymph nodes
what is melanoma?
cancer involving the melanocytes of the skin
which cells are involved in acute lymphocytic leukemia?
immature abnormal B cells (blasts)
Which parts of the body are affected by ALL?
Bone marrow and blood affected
Also common for liver, spleen or lymph nodes to become enlarged
What are the clinical signs of ALL?
Anaemia, low white blood cell count, weight loss, malaise, fatigue
define thrombocytopenia
Absence of functional granulocytes
Blood platelet count is low
Give examples of tumour associated antigens (TAAs)
CD19, CD20, CD22
Define stem cells
at cell division, one or both daughter cells remain undifferentiated with the ability to give rise to another stem cell with the same capacity to differentiate and produce cells in each organ.
What is the cancer stem cell hypothesis?
That tumour cells/cancer cells can self-renew. They can produce the bulk of cells within a tumour, may only compose 1% of the actual tumour.
what is the difference between cancer stem cells and normal stem cells?
cancer stem cells have chemo-resistance, tumourigenic and metastatic activities.
Why are cancer stem cells a target for treatment?
They are thought to be resistant to most therapies, so when the tumour is reduced/ bulk is destroyed, the CSCs can continue to self-renew and regrow the tumour.
What are tumour associated antigens (TAAs)?
self-proteins which are minimally expressed by healthy tissues but constitutively overexpressed in cancer cells as a result of their malignant profile
Give examples of TAAs
VEGF, HER2, hTERT, CEA, CD19
Tumour-specific antigens (TSAs) definition:
Exclusively restricted to tumours, not found on healthy tissues. Caused by malignant mutations or the expression of viral antigens
what antigen is overexpressed in the vast majority of colon cancers?
CEA
what is CEA
Expressed in fetal development, an oncofetal protein
is CEA presented before or after thymic education?
before thymic education, perceived as foreign as a result