A novel peptide from alpha5 helix of Asterina pectinifera cyclin B conjugated to HIV-Tat(49-57) with cytotoxic and apoptotic effects against human cancer cells.

A series of novel peptides from various motifs of Asterina pectinifera cyclin B and their derivatives conjugated to HIV-Tat(49-57) were designed and synthesized. Their bioactivities on two human cancer cell lines were determined. Among them, Tat-a5 (KAQIRAMECNILGRKKRRQRRR) exhibited significant cytotoxic effects on cancer cell lines EC-9706 and HCT-116. Tat-a5 could arrest cancer cells at G(2)/M phase and make them apoptotic. Our results suggested that Tat-a5 could be a novel leading peptide with anticancer activity.