Cancer chemoprevention

Cancer Chemoprevention

Phytochemicals

1. Detoxification

Nrf2

Antioxidant enzymes

Phase 2 enzymes

Promotes transcription of antioxidant genes and Enhances biotransformation of carcinogens

2. Down-regulation of COX-2 & PGE2 pathway

Inflammatory mediators e.g. COX-2

Prevent epithelial cell proliferation angiogenesis, decrease mutagens and anti-apoptotic proteins etc.

3. Apoptosis induction

Anti-apoptotic proteins e.g. Bcl2

Pro-apoptotic proteins e.g. Bax

Caspases activation to promote apoptosis by death receptor or

mitochondrial pathway.

4. Cell cycle arrest

G1 & G2/M arrest

CDK inhibitors

Cyclins

Regulation of cell cycle process and Prevent cell division.

5.Inhibition of Angiogenesis

Pro-angiogenic factors e.g. VEGF, Angiogenin

Anti-angiogenic factors e.g. Angiostatin, endostatin

Prevent formation of new blood vessels

6. Upregulation of GJIC

Connexons

Increase in number of channels to allow transmission of growth

inhibition factors.

7. Modulation of signal transduction pathways

Notorious transcription factors e.g. Nf-kB, MAPK, C-Myc

Lead to tumour supression, apoptosis induction, angiogenesis inhibition,

decrease in inflammatory bodies etc.