Carcinogenesis Flashcards
Carcinogenesis
The transformation of normal cells to neoplastic cells through permanent genetic alterations or mutations
Oncogenesis
Benign and malignant tumours
Is carcinogenesis a uni-step or multistep process?
multistep
Carcinogens are
agents known or suspected to cause tumours
Oncogenic agents are
tumour causing
Carcinogenic agents are
cancer causing
Agents that act on DNA are…
mutagenic
85% of cancer risk is e_____
environmental
What is the latent interval?
Time between exposure to carcinogenic agent and developing cancer
What is thorotrast?
Colloidal suspension of thorium, radioactive used as a trace. Long half life. Irreversibly ingested by phagocytes, particularly Kupffer cells. Emits alpha particles, leads to angiosarcoma in liver.
Classes of carcinogens
Chemical,
Viral,
Ionising and non-ionising radiation,
Hormones, parasites and mycotoxins,
Miscalleneous
Most chemical carcinogens require metabolic conversion from pro-carcinogens to u____ carcinogens
ultimate
Polycyclic aromatic hydrocarbons can cause what type of cancer?
Lung cancer and skin cancer (from smoking and mineral oils)
Aromatic amines can cause what cancer?
Bladder cancer (rubber/dye workers)
Nitrosamines can cause what cancer
Gut cancer (proven in animals)
Alkylating agents can cause what cancer?
Leukaemia (used in chemotherapy, small risk in humans)
Viruses cause approx. ___% of all cancers
10-15%
Most cancer causing viruses are ___ based
DNA (rather than RNA)
Human Herpes Virus (HHV8) is associated with
Kaposi sarcoma
Epstein Barr Virus (EBV) is associated with
Burkitt lymphoma, Nasopharyngeal carcinoma
Hepatitis B Virus (BHV)
Hepatocellular carcinoma
Human Papillomavirus (HPV)
Squamous cells carcinomas of the cervix, penis, anus, head and neck
Merkle cell polyomavirus (MCV)
Merkle cell carcinoma (neuro-receptors in skin)
The RNA virus HTLV-1 (human T-lymphotrophic virus)
Adult t-cell leukemia
The RNA virus HCV (hepatitis C virus)
Hepatocellular carcinoma
UV light (UVA or UVB) increases risk of…
BCC, melanoma, SCC (skin cancers)
What conditions increases risk of cancer from UV light?
Xeroderma pigmentosum
X-rays and gamma rays are i____ radiation
ionising
True or false, oestrogen can increase risk of cancer?
True (increased oestrogen leads to increased mammary/endometrial cancer)
Anabolic steroids leads to increased risk of…
hepatocellular carcinoma
Mycotoxin Aflatoxin B1 increases risk of…
hepatocellular carcinoma
Parasite chloronorchis sinensis
Cholangiocarinoma
Shistosoma parasite can cause what kind of cancer?
Bladder cancer
Asbestos and certain m___ are miscellaneous carcinogens
metals
There is decreased ____ cancer in those with darker skin (melanin)
skin
There is increased o___ c____ in India and south east Asia due to reverse smoking and betal chewing
oral cancer
Excess alcohol use increase risk of cancers of the…
mouth, oesophagus, liver, colon and breast
Exercise reduces risk of c___ and b____ cancer
colon, breast
What increases risk of HPV-related cancer?
Unprotected sex
