[The relationship between sensitivity to arsenic trioxide and antioxidative capacity of malignant hematopoietic...

To detect the relationship between sensitivity of malignant hematopoietic cells to arsenic trioxide (As2O3) and cellular capacity against oxidation.

Nine cell lines derived from hematopoietic malignancies were treated with As2O3 in vitro. Apoptosis was assessed by cellular viability, cytomorphology and flow cytometry. The As2O3-treated cells were examined for glutathione (GSH) level and activity of catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST) and glutathione peroxidase (GPX).

Of the 9 cell lines examined, the acute promyelocytic leukemia cell line NB4 and its retinoic acid-resistant subclones R2 and MR2, the Burkitt lymphoma cell line Namalwa and multiple myeloma cell line RPMI 8226 were sensitive to As2O3-induced apoptosis while the acute T cell leukemia cell line (Jurkat) and 3 cell lines (HL-60, U937, K562) of myelogenous leukemia origin were not. In comparison with the sensitive cell lines, higher activity of CAT was found in HL-60 and U937, higher level of GSH in Jurkat, and both in K562. However, activity of GPX, GST and SOD did not significantly correlate with their resistance to As2O3-induced apoptosis.

Intracellular GSH level and/or catalase activity are important factors to determine sensitivity of malignant hematopoietic cells to As2O3-induced apoptosis.