Cancer MBBS.pptx

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1. Uncontrolled growth and cell proliferation results in mass (tumor) That invades neighboring tissues and may metastasize to more distant sites. Some cancers, do not form tumors (Blood, Skin etc.) Its most common and severe problems of clinical medicine.

2. p53 E ncodes a phosphoprotein with 53,000 MW. It blocks the cells that have damaged DNA by triggering the blocking of cell division until the damage is repaired. If the DNA damage is severe, it directs the cell to commit suicide by triggering apoptosis. Most tumours absence of p53, others show mutant non-functional p53. S uppress transformation ability of oncogenic viruses and also activates the expression of genes that suppress cell proliferation.

3. Common Tumor Markers Name Increased in Alpha Fetoprotein Hepatoma , Germ cell Tumours Carcinoembryonic antigen Colorectal, Gastro and Lung Cancer Beta HCG Choriocarcinoma Prostate Specific Antigen Prostate cancer Calcitnin Medullary carcinoma of Thyroid CA -125 Ovarian cancer Alkaline phosphatase Bone secondaries Neuronal specific enolase Nervous system cancer Bence Jones Protein Lymphatic Cancer

4. Anticancer Drugs Surgery and radiotherapy – most effective to reduce the initial tumour load. Chemotherapy - cytotoxic drugs reduces doubling time of cancer cells

5. Common anticancer drugs Name Type Mode of action Methotrexate Folic acid analogue Competitive inhibitor of dihydrofolate reductase. THFA-nucleotide synthesis 6-Mercapto purine Purine analogue Inhibits the conversion of IMP to AMP 5-fluoro uracil Pyrimidine analogue Inhibits thymidylate synthase Cyclo - phosphamide Alkylating agent Cross linking of bases of DNA; inhibition of strand separation