Effects of ultrasound irradiating hydroxycamptothecin-loaded microbubbles on apoptosis and expression of related protein in human hepatoma SMMC-7721 cells / 中华超声影像学杂志

ABSTRACT

Objective To investigate the effects of ultrasound irradiating hydroxycamptothecin (HCPT)-loaded microbubbles on apoptosis in human hepatoma SMMC-7721 cells, and to clarify its probable mechanism. Methods The SMMC-7721 cells were randomly divided into six groups as follows: control group, blank liposome microbubbles plus ultrasound, HCPT-loaded microbubbles, HCPT, HCPT plus ultrasound,and HCPT-loaded microbubbles plus ultrasound. Apoptosis was ascertained by Annexin V-Fire/ PI and TUNEL methods. The expression of Bcl-2 and Bax protein was detected by immunocytochemistry staining technique. Results In the group of HCPT-loaded microbubbles plus ultrasound,the apoptosis rate at early term was found to reach (12.18 ± 1.38)% by Annexin V-Fitc/PI assay, brown-colored positive apoptotic cells were observed and the apoptosis rate at advanced term was found to reach (34.25 ± 1.83)% with TUNEL method. The expression of Bcl-2 was found to decrease,the expression of Bax increase,and the ratio of Bcl-2/bax significantly decrease by immunocytochemistry staining technique in the same group. Differences with other groups were significant. Conclusions The method of ultrasound irradiating HCPT-loaded microbubbles can notability induce human hepatoma SMMC-7721 cells apoptosis. The decrease in the ratio of Bcl-2 to Bax might be responsible for cells apoptosis.