Antitumor Protein (AP) from a Mushroom Induced Apoptosis to Transformed Human Keratinocyte by Controlling the Status of pRB, c-MYC, Cyclin E-CDK2, and p21^WAF1 in the GI/S Transition

Abstract

Antitumor protein (AP) from a mushroom, induced the morphological changes typical to apoptosis such as nuclear condensation, aneuploidity, and DNA fragmentation at concentrations as low as 5–20 ng/ml to cancer cells. Molecular alterations related to cell cycle, especially G1/S transition were investigated with a human keratinocyte transformed with oncoproteins, E6 and E7 of human pappiloma virus(HPV)-16. AP didn’t alter significantly an oncosuppressor p53 level, but induced hyperphosphorylation of pRb. Time-dependent change of G1 cyclins, cdk2 and cdk4 after addition of AP showed that expression level of cdk inhibitors, INK4 family, and p27KIP1 did not altered, while that of p21^WAF1 was downregulated.