Effects of Antrodia camphorata extracts on the viability, apoptosis, [Ca ²⁺ ] _i , and MAPKs phosphorylation of OC2 human oral cancer cells

The effect of Antrodia camphorata (AC) on human oral cancer cells has not been explored. This study examined the effect of AC on the viability, apoptosis, mitogen-activated protein kinases (MAPKs) phosphorylation and Ca ²⁺ regulation of OC2 human oral cancer cells. AC at a concentration of 25 μM induced an increase in cell viability, but AC at concentrations ≥ 50 μg/ml decreased viability in a concentration-dependent manner. AC at concentrations of 100-200 μg/ml induced apoptosis in a concentration-dependent manner as demonstrated by propidium iodide staining. AC (25 μg/ml) did not alter basal [Ca ²⁺ ] _i , but decreased the [Ca ²⁺ ] _i increases induced by ATP, bradykinin, histamine and thapsigargin. ATP, bradykinin, and histamine increased cell viability whereas thapsigargin decreased it. AC (25 μg/ml) pretreatment failed to alter ATP-induced increase in viability, potentiated bradykinin-induced increase in viability, decreased histamine-induced increase in viability and reversed thapsigargin-induced decrease in viability. Immunoblotting suggested that AC induced phosphorylation of ERK and JNK MAPKs, but not p38 MAPK. Collectively, for OC2 cells, AC exerted multiple effects on their viability and [Ca ²⁺ ] _i , induced their ERK and JNK MAPK phosphorylation, and probably evoked their apoptosis.