Molecular Biology of Cancer Flashcards

Question

Other origins of cancer cells?

Answer 1

-1% - from connective tissue (sarcomas ) - 8% - from haemapoetic cells (lymphomas, leukaemias )

Answer 2

e.g. cancer of the lip -99% survival cancer of lung - 8% survival

Answer 3

- early diagnosis - lack of spread to other sites - response to treatment - quality of care

Answer 4

- mutations in the DNA that codes for genes whose products are normally involved in the control of division, differentiation and cell survival - most mutations are somatic ! - some are inherited ! - this has lead to great insights into normal growth and development

Answer 5

- because many unlikely mutations must accumulate in one cell - mutations that affect genetic stability are of especial importance -these mutations allow new variants to arise more quickly - cancer cells are genetically unstable which allows rapid evolution - therefore allowing drug resistance

Answer 6

1. mild dysplasia (25-30 divisions) 2. severe dysplasia (100 million cells visible on xray) 3. carcinoma in situ (1000 million cells tumour is palpable ) 4. invasive carcinoma - (tumour breaks through basement membrane ) 5. malignant metastasis ( 1,000,000 million cels tumour throughout body and organs - death!)

Answer 7

- avoiding immune response - tumour promoting inflammation - deregulating cellular energetics - genome instability and mutation - the tumour microenvironment is very different from normal tissues. - the tumour cells have adapted a glycotic metabolism

Answer 8

- activation of genes by mutation that promote cell proliferation and cell survival - dominant gain of function mutations - protooncogene mutates to oncogene - regulated growth signal /survival signal ==== mutation === unregulated growth signal / survival signal - inactivation of genes by mutation that normally limit cell proliferation and cell survival - recessive loss of function mutations - tumour supresser gene ==== mutations ==== mutant tumour supressor gene

Answer 9

- because loss of function mutation need to lose both parental copies for affect to be seen - if you inherit a germ line mutation in one you are at a greater risk of developing cancer.

Answer 10

- p53 gene - mutant in more than 50% of human cancerss - part of cells checkpoint repsonse to DNA damage - retinoblastaoma gene - mutant in all retinoblastomas but also lung and other cancers. - key negative regulator of the transcription of genes needed for cell cycle. -adenomatous polypossis coli gene (APC) mutant in most colorectal cancers at early stage in disease. involved in chromosome stability HmutS gene - mutant in some forms of colorectal cancer - mutations cause a defect in DNA mismatch repair

Answer 11

- since somativ mutation of DNA underlies cancer development it is thought that: 1. mutagens are carcinogens 2. cancer is avoidable if mutagen exposure can be reduced. 3. mutagen testing can help identify cancer causing agents in the environment.

Answer 12

- mutant growth factor receptors - single cascade components - transcription factors - cell-cell components - anti- apoptotic factors

Answer 13

it is found that in cancer there is chromosomal instability - tumours are aneuploid ( incorrect number - triploid, haploid ) - tumours have many brokem and rearranged chromosomes clearly seen using FISH and CGH techniques = careful cytology on leukaemias showed certain common very conserved events.

Answer 14

- cytological examination of tumours shows double minute chromosomes - cytological examination of tumours shows HSRs homogenously staining regions - both contain multiple copies of same Chromosomal fragment.

Answer 15

- Human genome sequence ' complete' - cancer genome sequencing project - use of next generation sequencing - exosome sequencing

Answer 16

- the tumour cells are often exposed to low oxygen, hypoxia or inflammation

Answer 17

1. escape from the tumour 2. invasion of vascular system 3. movement through the blood stream 4. homing to distant organs 5. attachment 6. invasion

Answer 18

- understand the genetic defect - find the achillies heel of the cancer - block new blood vessel formation - change the microenvironment - target on mutant cells - personalised cancer treatment.

Molecular Biology of Cancer Flashcards

(42 cards)