CANCER: ROLE OF VITAMIN C AND E IN THERAPY Gandhari , Aditi, Divya, Ankita CANCER Occurrence of cancer Mortality rates What is Cancer? Cancer is a class of diseases in which a group of cells display uncontrolled growth, invasion and sometimes metastasis . Causes Mutation: chemical carcinogens, liver cancer by aflatoxin b Mutation: ionizing radiation, skin cancer Viral infection, cervical cancer Bacterial infection, gastric lymphomas Hormonal imbalances, endometrial cancer Immune system dysfunction, sarcoma Heredity, breast cancer Stages of cancer Properties of a cancerous cell Mechanisms used by cancer cells Mechanism of cancer formation Cancers are caused by a series of mutations There are two broad categories of genes which are affected by these changes • Oncogenes • Tumor suppressor genes TREATMENT Surgery Chemotherapy Radiation therapy Surgery Is the removal of the cancer cell mass Not a very effective & successful cure followed by chemo or radiation therapy Chemotherapy It refers to antineoplastic drugs used to treat cancer. Types of Chemotherapeutic Drugs Alkylating agents: Cisplatin, cyclophosphamide Antimetabolites: mercaptopurine Plant alkaloids: vinca-alkaloids Topoisomerase inhibitors: etoposide Chemotherapy drug targets Kinetics of tumor growth Side effects of Chemotherapy Depression of the immune system Fatigue – severe or mild anemia Tendency to bleed easily Gastrointestinal distress – nausea and vomiting Hair loss The development of secondary neoplasia Radiation Therapy • • • • High energy rays X rays Gamma rays Particle beams Proton beams Neutron beams Destroy cancer cells & keep them from reproducing Two types of radiation therapy External radiation therapy – radiations incident from outside. Internal radiation therapy – radioactive source inside body. The radiation – units are Gray (1joule/kg) and Sievert (1joule/kg). Drawbacks of radiation therapy Kills normal cells also. Fatigue and skin irritation. Fibrosis - Tissues become less elastic over time due to a diffuse scarring process. Secondary cancer Need for improved treatment Destructive effect of radiation and/or chemotherapy on normal cells in addition to cancer cells. Dose limiting toxicity of these treatments. Numerous side effects of chemotherapy. Need for selective destruction of cancer cells. VITAMIN C & E IN CANCER PREVENTION AND TREATMENT Therapeutic effect of Vitamin C Important raw material for the development of immune system cells. Generates and mobilizes specialized cells that fight cancer and infections. Crucial first line of defense against mutated cells Vitamin supplement in diet of patient Increases tolerance to radiation therapy – radioprotection to normal cells Enhances tumor destruction – radiosensitization of cancer cells Upregulation of immune system Prevents glucose raising effects of chemo drugs Vitamin C improved survival rates Therapeutic effects of Vitamins E & C Inhibition of cancer by the quenching of free radicals Direct effect on tumor cells induction of differentiation Cell cycle inhibition & induction of apoptosis Enhanced immune system response to tumors Production of free radicals H2O h Lipid peroxidation R-OH + .O-O-H .O + .OH + H3O+ + Osinglet + .O-O-H R-O-O. +H2O Oxidative stress Vitamin E and C as antioxidants Conventional knowledge – prevent DNA damage to some extent. Inhibit cancer formation by scavenging reactive oxygen or nitrogen species essential for HIF-1 protein. Functions of HIF-1 Free radicals dependent • Important for survival of growing tumors as – Converts sugar to energy Constructs new blood vessels Antioxidants remove free radical – HIF-1 disabled • Chemistry of vitamin C 2R`+ +2R-H Ascorbic acid Dehydroascorbic acid Chemistry of vitamin E Dimerises & excreted Vitamin E succinate induced apoptosis Transforming growth factor-ß signaling pathway Fas/APO-1/CD95 signaling pathway Mitogen-activated protein kinase signaling pathway growth inhibition and apoptosis death receptor VES upregulates TGFβ receptos Cancer cell downregulates it MAP kinase cascade Receptor mediated pathway of apoptosis Pathway by which TGFβ functions in a normal cell Summary • • • Cancer - cells with uncontrolled growth & metastasis. Caused by mutations in the genes. Treated in multisteps clubbing various treatments. Vitamin C & E reduce side effects of radiation and chemo therapy. Upregulate immune system. Inhibit functioning of HIF-1 protein. VES is known to cause apoptosis in cancer cells. Cancer can be prevented Healthy diet rich in oxidants. Decrease intake of too much fried food. Exercise regularly. Reduce stress levels. References CELL AND MOLECULAR BIOLOGY- GERALD KARP SCIENCE DAILY PUBMED AMERICAN CANCER SOCIETY INMAS RESEARCH PAPERS WIKIPEDIA THANK YOU