Objective To study the expression of PTEN and its significance in doxorubicin-treated gastric cancer cells. Methods (1) Gastric cancer BGC-823 cells were treated with doxorubicin. Cell proliferation and apoptosis were evaluated by MTF and flow cytometry. The expression of PTEN at the mRNA and protein level were determined by RT-PCT and Western blot, respectively. (2)The gastric cancer xenografts model was constructed. The apoptosis of gastric cancer xenografts cells was determined by TUNEL. The expression of PTEN at the mRNA and protein level were detected using RT-PCR and Western blot, respectively. (3) BGC-823 cells were transfected with PTEN siRNA before addition of doxorubicin. The proliferation and apoptosis of these cells as well as the expression level of PTEN protein were determined. Results (1) After administration of doxorubicin, the proliferation of BGC-823 cells was inhibited in a time-dependent manner. (2) Doxorubicin significantly induced apoptosis of BGC-823 cells. (3) Doxorubicin treated BGC-823 cells showed a significant increase in the expression of PTEN at the mRNA and protein level in a time-dependent manner. TUNEL assay also showed a significant increase of apoptosis rate in gastric cancer xenografts treated with doxorubicin compared with control group [(28. 11± 1.05) % vs (2. 78 ± 1.63) %]. The expression of PTEN at the mRNA and protein level in the gastric cancer xenografts were significantly increased after administration of doxorobicin (0. 5667 ± 0. 0043 vs 0.2217±0.0063,0.14±0.26 vs 0.04±0.15,P <0.05). (4) After treated with doxorubicin, the expression of PTEN in siRNA-transfected BGC-823 cells was significantly higher than that in non-transfected BGC-823 cells (P < 0. 0001). The apoptosis of PTEN siRNA-transfected BGC-823 cells was significantly decreased compared with non-transfected BGC-823 cells [(10. 35 ± 1.04) % vs (31.37 ± 3.58) %, P < 0. 05]. Conclusion Doxorubicin can effectively inhibit the growth and induce the apoptosis of BGC-823 gastric cancer cells. Increasing PTEN protein may be one of the main mechanism involved in this effect.

Establishing a governance structure and an operational model that is compatible with modern hospital manage-ment systems,deepening the reform of hospital management institutions,and exploring the implementation of Super-department System with unified functions are inevitable requirements for promoting the high-quality development of public hospitals.Hospital of Stomatology of Sun Yat-sen University takes the Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era as a guide and fully implements the"Opinions of the General Office of the State Council on Promoting the High Quality Development of Public Hospitals,"integrates party building work and vocational work,carries out practical exploration of the reform of the Su-per-department System,and leads the hospital to achieve phased results in high-quality development.