Development of mouse skin tumors by 7, 12- dimethylbenz (a) anthracene and its prevention by C-phycocyanin involve the regulators of cell cycle and apoptosis

We evaluated the 7, 12dimethylbenz (a) anthracene (DMBA) induced mouse skin tumor development as a function of time and its control by C-Phycocyanin (C-PC, a phycobiliproteins from Spirulina). Oral administration of C-PC inhibited the DMBA induced skin tumor development in term of number and the size of tumors. C-PC administration also prevented the DMBA caused molecular alterations in terms of mutp53, Bcl-2, Cdc25A and p27, Bcl-2 at different end points. There were no tumors at 1 week or 1 month after DMBA exposure but appeared after 4 months which were prevented in presence of C-PC. We show that C-PC prevented the skin tumor development possibly due to its involvement in the inhibition of DMBA mediated p53 mutation, increasing apoptosis and modulating cell cycle regulators in terms of higher expression of Bcl-2 and Cdc25A or p27genes. These results make the basis of detailed study of C-PC as a potentially safe antitumor agent. Correspondence to: Krishna P. Gupta, Ph.D., Environmental Carcinogenesis Division, CSIR-Indian Institute of Toxicology Research, India, Tel: +91-5222627586, Ext.313, Fax: +91-522-2628227; E-mail: [email protected]