Signaling crosstalk of FHIT, CHK2 and p38 in etoposide induced growth inhibition in MCF-7 cells

► FHIT siRNA completely reversed etoposide cytotoxicity in MCF-7 cells. ► Etoposide activates CHK2 prior to p38 and reduces FHIT expression time dependently. ► FHIT siRNA shortens CHK2 activation with no significant effect on p38 activation. ► p38 block augments CHK2 activation and block of p38 or CHK2 affect FHIT expression. ► The study shows a time dependent complex crosstalk of FHIT, p38 and CHK2 pathways.