High bax expression is a good prognostic indicator in acute myeloid leukaemia

Most cytotoxic drugs kill cells by instigating the process of apoptosis and it has been suggested that apoptotic markers may provide an indication of tumour chemosensitivity. The aim of this study was to determine if such a r elationship exists in acute myeloid leukaemia (AML). The levels of spontane ous apoptosis, bcl-2 and bax were evaluated in 56 newly diagnosed AML patie nts to determine if they correlated with a response to cytotoxic therapy. S pontaneous apoptosis was lower, but bcl-2, bax and the bcl-2/bax ratio were higher in AML compared with normal individuals. AML patients with high bax expression at diagnosis had significantly better prognosis for disease-fre e survival, event-free survival and overall survival (P = 0.016). In the st andard risk group, high bax expression was in keeping with significantly im proved survival. Multivariate analysis revealed bax to be an independent pr edictor of survival. There was a significant reduction in bcl-2 and bax exp ression when AML patients entered complete remission and also in relapsed A ML, patients who entered a second remission. This study suggests that bax i s a useful prognostic indicator in AML and may assist with therapeutic deci sion-making for patients in the standard risk category.