Which assay are you using, Annexin V? Not including a positive control will, at the very least, make your experiment more difficult to interpret. It may also make it impossible to interpret, depending on the particulars of the experiment. There is evidence that heat shock can induce apoptosis, so you might try simply heat treating your cells, 

(Example of said evidence: http://www.nature.com/articles/srep04469), though it may also induce cell death via other pathways. 

Thanks a lot. Yes annexin v. 

You can Use simply H2O2  (Hydrogen peroxide) to induce apoptosis

can tell how much h2o2 ?