To investigate the cytotoxic effect of PAC over time on thyroid cancer cells, CAL-62 cells were treated with PAC (10 μM) at variable time periods 0, 24, 48 and 72 h, and the proportion of apoptotic cells was determined by the Annexin V/PI-Flow cytometry assay. The gene discussed is ANXA5; the disease is thyroid gland carcinoma.