Oolong tea polyphenol extract induces apoptosis in human stomach cancer cells.

The exposure of human stomach cancer KATO III cells to oolong tea polyphenol extact [OTPE] containing oolong tea polyphenol trimer [OTP trimer] as a main component, led to both growth inhibition and the induction of apoptosis. Morphological change showing apoptotic bodies was observed in the cells treated with OTPE. The fragmentation by OTPE of DNA to oligonucleosomalsized fragments that are characteristics of apoptosis was observed to be concentration- and time-dependent. These data suggest that the growth inhibition by OTPE results from the induction of apoptosis in the KATO III cells.