Induction of apoptosis by ethanolic extract of leaf of Dillenia pentagyna Roxb. in A549 cells via NF-κB pathway

•Ethanolic extract of leaves of Dillenia pentagyna (EELDP) kills human cancer cells.•EELDP is not cytotoxic to normal L-132 cells.•EELDP significantly increases apoptosis by increasing Bax to Bcl2 ratio.•EELDP triggers cytochrome-c release, caspase-3 activation, and nuclear fragmentation.•Combined treatment of EELDP and NF- κB inhibitor significantly enhances apoptosis.