ONC Flashcards
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
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Define Cancer
*LOB; Define the terms “cancer”, “carcinogenesis” and “carcinogen”.
A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems
NIH
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
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What are the most common cancers?
*LOB; Define the terms “cancer”, “carcinogenesis” and “carcinogen”.
More than half of new cases are
Breast
Prostate
Lung
Bowel
NIH
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
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Define carcinogenesis and the four steps of cancer formation
*LOB; Define the terms “cancer”, “carcinogenesis” and “carcinogen”.
The generation of cancer:
Initiation
Promotion
Progression
Malignant conversion
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Cancer is a genome disease
*LOB; Define the terms “cancer”, “carcinogenesis” and “carcinogen”.
Epigenetic, genomic alt
Altered protein
Altered pathways
Altered biology
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
What are the hallmarks of Cancer
Features of cancers
*LOB; Define the terms “cancer”, “carcinogenesis” and “carcinogen”. Demonstrate an understanding of the ‘Hallmarks of Cancer’
ONC Mechanisms of Oncogenesis by
Define carcinogen
*LOB; Define the terms “cancer”, “carcinogenesis” and “carcinogen”.
Substances and exposures that can lead to cancer
directly- c/s breakage, fusion etc
indirect- ROS, infl,
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Multistage Theory of Carcinogenesis.
*LOB Explain the Multistage Theory of Carcinogenesis.
Chromosomal instability pathway (c/s loss and gain)
Mutations in the DNA Repair pathways
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
What are driver mutations?
*LOB Explain the Multistage Theory of Carcinogenesis.
2-8 driver mutations are required for carcinogenesis
confer growth/survival advantage
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
What are passenger mutations
*LOB Explain the Multistage Theory of Carcinogenesis.
Mutations that are not enough to cause oncogenesis
Conssequence of loss of function of key DNA repair genes
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Targets for cancer therapy
*LOB Explain the Multistage Theory of Carcinogenesis.
Hormone responsive tumours= remove oestrogen and androgen
Growth receptor= drugs ‘-mab’ to target EGFR HER2 VEGF
Singalling pathways = BRAF MTCH block
Tumour macroenvironment= checkpoint inhibitor molecules on T Cells can be left on longer. CTLA4 and PD1
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Characteristsics of Primary tumour
*LOB Explain the Multistage Theory of Carcinogenesis.
Antigenicity
Growth Rate
Response to hormones
REsponse to cytotoxic drugs
Capacity for invaion on metastasis
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Describe the four main types of carcinogens.
*LOB Describe the four main types of carcinogens.
Chemical
Physical
Viral
Hereditary cancer predisposition syndromes
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Describe the four main types of carcinogens.
*LOB Describe the four main types of carcinogens.
Chemical
Physical
Viral
Hereditary cancer predisposition syndromes
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Chemical carcinogens
*LOB Describe the four main types of carcinogens.
Give examples of carcinogens and describe their mechanisms of action.
Cisplatin and carboplatin,
Irreversibly bind across DNA so unable to be read.
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Physical carcinogens
*LOB Describe the four main types of carcinogens.
Give examples of carcinogens and describe their mechanisms of action.
UV
Gamma
X Rays
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Viral carcinogens
*LOB Describe the four main types of carcinogens.
Give examples of carcinogens and describe their mechanisms of action.
Adenovirus- DNA
Retroviridae- RNA
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Hereditary cancer predisposition syndromes (genetic risk factors) carcinogens
*LOB Describe the four main types of carcinogens.
Give examples of carcinogens and describe their mechanisms of action.
Gene mutations involving oncogenes (activation) or/and tumour suppressors (inactivation) common to other malignancies (TP53- Li-Fraumeni syndrome, NF1-Neurofibromatosis) or specific to the cancer type. Lynch syndrome.
Chromosome aberrations:
Translocations (e.g. BCR-ABL in Leukaemia).
Numerical disorders (e.g. trisomy 21-Down syndrome).
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
What are the mechanisms of DNA damage
*LOB: Give examples of carcinogens and describe their mechanisms of action.
`ONC Mechanisms of Oncogenesis by Dr Mark Bodman-Smith
Repair mechanisms of DNA damage
*LOB: Give examples of carcinogens and describe their mechanisms of action.
BER
NER
Mismatch
Recombination repair
ONC Tumour Progression, Invasion, Metastasis by Dr Bodman-Smith
Define progression
*LOB: Understand the molecular mechanisms involved in tumour progression, invasion and metastasis.
: Unlimited growth (not self-limited as in benign tumours) - as long as an adequate blood supply is available to prevent hypoxia.
ONC Tumour Progression, Invasion, Metastasis by Dr Bodman-Smith
Define invasiveness
*LOB: Understand the molecular mechanisms involved in tumour progression, invasion and metastasis.
: Migration of tumour cells into the surrounding stroma where they are free to disseminate via vascular or lymphatic channels to distant organs.
ONC Tumour Progression, Invasion, Metastasis by Dr Bodman-Smith
Define metastasis
*LOB: Understand the molecular mechanisms involved in tumour progression, invasion and metastasis.
Spread of tumour cells from the primary site to form secondary tumours at other sites in the body.
ONC Tumour Progression, Invasion, Metastasis by Dr Bodman-Smith
What is the molecuolar basis for tumour progression?
*LOB: Understand the molecular mechanisms involved in tumour progression, invasion and metastasis.
Acquisition of specific mutations – by carcinogens, multiple hits.
Clonal expansion – by tumour promoters.
Genomic instability – by DNA repair defects, aneuploidy (abnormal chromosome number), loss of heterozygosity.
Epigenetic changes – by gene promoter methylation.
ONC Tumour Progression, Invasion, Metastasis by Dr Bodman-Smith
Tumour progression is associated with…
*LOB: Understand the molecular mechanisms involved in tumour progression, invasion and metastasis.
with cellular heterogeneity