Apoptosis of T-leukemia and B-myeloma cancer cells induced by hyperbaric oxygen increased phosphorylation of p38 MAPK

Tumor cells with different origins have different threshold to apoptosis. Hematopoietic (Jurkat, NCI-H929) cells and non-hematopoietic (A549, MCF-7) cells were received hyperbaric oxygen (HBO2) treatment from 2.5 to 3.5 atmosphere absolute (ATA) of 100% oxygen for 6 h, and a significant percentage of apoptosis were shown only in hematopoietic Jurkat and NCI-H929 cells by either Annexin V or TUNEL assay. Oxidative stress was illustrated higher in HBO2-treated hematopoietic cells by superoxide fluorochrome detectors. HBO2 treatment leads to caspase-3, caspase-7 activation and further cleavage of PARP within cells. Furthermore, the increased phosphorylation of p38 MAPK was demonstrated in both Jurkat and NCI-H929 cells.