Abstract: 【Objective】 To study the inhibitory effect of cantharadin extracted from meloids Mylabris cichorii on human laryngeal carcinoma HEP-2 cell lines and human gastric carcinoma BGC-823 cell lines, and the influence on cell cycle. 【Methods】 Human laryngeal carcinoma HEP-2 cell lines and human gastric carcinoma BGC-823 cell lines were cultured by cell culture technique. MTT colorimetry was used to evaluate the inhibitory effect of cantharidin on cell grouth. Flow cytometry was used to measure the induction of cell cycle arrest. Microscope was used to observe the morphological changes of the cells. 【Results】 Cantharidin displayed the inhibitory effect on the growth of HEP-2 cells at the concentration of 1.28 μmol/L. The inhibition was in a dose-dependent manner with the IC50 value of 2.88 μmol/L. And cantharidin displayed the inhibitory effect on the growth of BGC-823 cells at the concentration of 20.4 μmol/L. The inhibition was in a dose-dependent manner with the IC50 value of 54.85 μmol/L. After HEP-2 cells were treated with 1.44 and 2.88 μmol/L cantharidin for 24 h, their distributions in G2-M phase and S phase increased from 8.21% to 22.29% and from 14.33% to 21.61%, respectively, while that in G0-G1 phase decreased from 77.45% to 56.10% and no apoptosis was induced. Cell shrinkage, membrane budding, and chromosome lagging of some HEP-2 cells were observed under microscope. 【Conclusions】 The results suggest that cantharidin may have higher application significance to the therapy of laryngeal cancer, as compared with that of gastric cancer. Cantharidin can inhibit the growth of human laryngeal carcinoma HEP-2 cell lines.

Key words: Meloids, cantharidin, laryngeal carcinoma, gastric carcinoma, cell culture, IC50, cell cycle