Objective    To explore the effects and molecular mechanisms of histone methylase G9a inhibitor BIX-01294 on apoptosis in esophageal squamous cell carcinoma (ESCC). Methods    MTT assay and Colony-forming Units were adopted to determine the effects of BIX-01294 on the growth and proliferation of ESCC cell lines EC109 and KYSE150. Flow cytometry was used to analyze the apoptosis status of ESCC cells after the treatment of BIX-01294. The effects of BIX-01294 treatment on the expressions of G9a catalytic product H3K9me2, DNA double-strand break (DSB) markers, and apoptosis-related proteins were detected by Western blotting. Results    BIX-01294 inhibited the growth of EC109 and KYSE150 cells in a dose-dependent manner (P<0.05), and BIX-01294 with the inhibitory concentration 50%(IC50) significantly inhibited the formation of colony (P<0.05). After 24 hours treatment of BIX-01294 (IC50), the apoptosis rate of EC109 cells increased from 11.5%±2.1% to 42.5%±5.4%, and KYSE150 cells from 7.5%±0.9% to 49.2%±5.2%(P<0.05). The expression level of the G9a catalytic product, H3K9me2, significantly decreased (P<0.05); while the expression of the DSB marker γH2AX was dramatically enhanced (P<0.05). We also found that the mitochondrial apoptosis pathway was activated and the expression levels of cleaved caspase3 and cleaved PARP were significantly elevated (P<0.05). Conclusion    BIX-01294, the inhibitor of methyltransferase G9a, prompted apoptosis in ESCC cells by inducing DSB damage and activating mitochondrial apoptosis pathway.

BACKGROUND: Thoracoscopic safe and effective hemostasis is an important condition for rapid rehabilitation of thoracic surgery. Placing hemostatic materials during surgery is a commonly used method in lung cancer laparoscopic surgery. Among them, resorbable oxidized cellulose is a commonly used hemostatic material. This research aims to observe the hemostatic effect of resorbable oxidized cellulose in lung cancer surgery. METHODS: A retrospective analysis of 42 patients with thoracoscopic lung cancer undergoing radical surgery in the Department of Thoracic Surgery, First Affiliated Hospital of Zhejiang University School of Medicine from July 1, 2018 to December 1, 2018, and intraoperative use of regenerative oxidized cellulose to stop bleeding The clinical and pathological data were selected and the perioperative indicators were selected as the outcome events for statistical analysis. RESULTS: The mean operative time was (120.5±57.3) min. The mean intraoperative blood loss was (26.8±21.6) mL. The average postoperative drainage volume was (513.6±359.5) mL. The average postoperative chest tube indwelling time was (2.6±1.2) d. CONCLUSIONS The use of absorbable regenerated oxidized cellulose in the radical operation of thoracoscopic lung cancer has a good hemostasis effect, and is suitable for hemostasis of wounds after lymph node dissection.