ACCEPTED FOR PUBLICATION IN NUTRITION AND CANCER, VOL 38, ISSUE #2
22- ENHANCING EFFECT OF PATENTED WHEY PROTEIN ISOLATE(IMMUNOCAL) ON THE CYTOTOXICITY OF ANTI-CANCER DRUG
Wayne Y. Tsai, Wen-Huei Chang, Ching-Hsein Chen, and Fung-Jou LuDepartment of Biochemistry, College of Medicine National Taiwan University, Taipei, Taiwan, R.O.C.ABSTRACT
– To determine the enhancing effect of a whey protein isolate on the cytotoxicity of a potential anti-cancer drug. baicalein, human hepatoma cell line HepG2 was assigned to grow in different media for four days, followed by the investigation of cell growth and apoptosis. Excluding the control group with normal medium, other three treatment media included whey protein isolate (marketed as Immunocal) medium, baicalein medium, and combined medium containing both Irnmunocal and baicalein. MTT assay indicated that cells grew in combined medium had a significantly lower survival rate compared to the cells grew in baicalein medium; in contrast, for the cells grew in Immunocal group, there was no significant difference on survival rate. In the investigation of apoptosis. compared to the cells in baicalein medium, cells in combined medium showed a higher phosphatidylserine exposure, lower rnitochondrial transmembrane potential and nearly 13 times more cells were detected undergoing apoptosis. We also demonstrated that Immunocal was able to reduce glutathione in HepG2 by 20% to 40% and regulated the elevation of glutathione, which was in response to baicalein. In conclusion, Immunocal seemed to enhance the cytotoxicity of baicalein by inducing more apoptosis, this increase in apoptotic cells may be in association with the depletion of GSH in HepG2. This is the first study to demonstrate, in vitro, that Immunocal may function as an adjuvant in cancer treatments.