Putranjivain A from Euphorbia jolkini inhibits proliferation of human breast adenocarcinoma MCF-7 cells via blocking cell cycle progression and inducing apoptosis

Putranjivain A, isolated from the whole plant of Euphorbia jolkini Bioss (Euphorbiaceae), was investigated for its antiproliferative activity in human breast adenocarcinoma MCF-7 cells. The results showed that putranjivain A inhibited the proliferation of MCF-7 by blocking cell cycle progression in the G0/G1 phase and inducing apoptosis. Enzyme-linked immunosorbent assay showed that putranjivain A increased the expression of p21/WAF1 concomitantly as MCF-7 cell underwent G0/G1 arrest. An enhancement in Fas/APO-1 and its two forms of ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), might be responsible for the apoptotic effect induced by putranjivain A. Our study reports here for the first time that the induction of p21/WAF1 and the activity of Fas/Fas ligand apoptotic system may participate in the antiproliferative activity of putranjivain A in MCF-7 cells.