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

SurgeryChemotherapyRadiation therapy

TREATMENT

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 & EIN 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 .O + .OH + H3O+ +

Osinglet + .O-O-H

Lipid peroxidationR-OH + .O-O-H R-O-O. +H2O

h

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

Dehydroascorbic acidAscorbic acid

2R`++2R-H

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

VES upregulates TGFβ receptos

Cancer cell downregulates it

MAP kinase cascade

death receptor

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

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