The protein encoded by the PIK3C2G gene belongs to the phosphatidylinositol -4,5-bisphosphonate 3 - kinase (PI3K) family, which plays a critical role in
cancer.28 Experimental evidence suggests that activation of PI3K signaling
enhances production of COX - 2 and PGE2, which results in inhibition of
apoptosis in colon
cancer cell lines that can be restored with NSAID - mediated blockade of PI3K.29
TRAIL -
enhanced apoptosis as measured by cleavage of caspase - 3 (Fig. 4I), and knockdown of ABL kinases increased the sensitivity of 1833 breast
cancer cells to the proapoptotic effects of TRAIL (Fig. 4, G to I).
In
cancer therapy, melatonin counteracts chemotherapy toxicity, by acting as an anti-oxidant agent, and promotes
apoptosis (programmed
cell death) of
cancer cells, thus
enhancing the toxicity of chemotherapy.