N-(2-hydroxyphenyl)acetamide (NA-2) and Temozolomide synergistically induce apoptosis in human glioblastoma cell line U87

Despite the modern therapies available for treating glioblastoma multiforme (GBM), it is still a deadly disease. The development of new therapeutic strategies for the management of gliomas is therefore crucial. The present study is designed to analyze the therapeutic potentials of synthetic compound N-(2-hydroxyphenyl)acetamide (NA-2) in the treatment of GBM as a single agent or in combination with Temozolomide (TMZ) on glioblastoma cells. MTT and TUNEL assays were used to detect the growth inhibitory effect and apoptotic activity of NA-2 alone and in combination with TMZ. Synergy was assessed using combination Index method. The expression of apoptosis related markers Bax, Bcl-2 and caspase-3 were assessed by RT-PCR, whereas, the active caspase-3 protein expression was determined using imunocytochemistry. Both NA-2 and TMZ inhibited the growth of U87 in a dose dependent manner. The combine administration of NA-2 (0.33 mM) and temozolomide (0.1 mM) significantly enhanced the cell growth inhibition and apoptosis. Furthermore RT-PCR and imunocytochemistry data revealed that cooperative apoptosis induction was associated with increased ratio of Bax to Bcl-2 and active Caspase-3 expression. Our findings support that NA-2 possesses strong apoptotic activity and the combined administration of NA-2 and TMZ may be therapeutically exploited for the management of GBM.