目的 探究雷帕霉素通過(guò)Fas/FasL信號(hào)通路治療食管癌及放療增敏的具體機(jī)制。方法 采用CCK-8和流式細(xì)胞分析評(píng)價(jià)ECA109細(xì)胞的凋亡能力。采用ECA109 sc構(gòu)建食管癌小鼠瘤體模型。將C57BL/6J小鼠分為對(duì)照組、放射組（4 Gy¹³⁷Cs γ射線）、雷帕霉素（雷帕霉素1.5 mg/kg）組、放射+雷帕霉素（4 Gy¹³⁷Cs γ射線+雷帕霉素1.5 mg/kg）組。收集并記錄各組小鼠的腫瘤體積及質(zhì)量、腫瘤抑瘤率及增殖系數(shù)，放療及雷帕霉素對(duì)其的增敏影響。采用酶聯(lián)免疫吸附試劑盒評(píng)估腫瘤組織中半胱氨酸蛋白酶3(Caspase-3)、B淋巴細(xì)胞瘤-2(Bcl-2)和Bcl-2相關(guān)X蛋白（Bax）水平。蘇木素–伊紅（HE）染色觀察小鼠食管癌的病理影響。Western blotting評(píng)估Fas/FasL信號(hào)通路的激活情況。結(jié)果 與放射組相比，放射+雷帕霉素組小鼠腫瘤體積、質(zhì)量顯著減小（P<0.001）。與放射組相比，放射+雷帕霉素組的抑瘤率及生長(zhǎng)延遲時(shí)間（TGD）顯著升高，腫瘤3倍倍增時(shí)間（TGT3）顯著延長(zhǎng)（P<0.05）。放射+雷帕霉素組出現(xiàn)大量腫瘤細(xì)胞崩解，間質(zhì)水腫更明顯。與放射組比較，放射+雷帕霉素組Bcl-2表達(dá)水平顯著降低，Bax、Caspase-3表達(dá)水平顯著升高（P<0.001）。與放射組比較，放射+雷帕霉素組ECA109細(xì)胞活力顯著降低（P<0.001）。Fas及FasL的表達(dá)在細(xì)胞中被抑制后，ECA109細(xì)胞活力顯著增加，ECA109細(xì)胞凋亡率顯著降低（P<0.001）。與放射組相比，放射+雷帕霉素組中Fas和FasL蛋白相對(duì)表達(dá)量顯著升高（P<0.001）。結(jié)論 雷帕霉素通過(guò)Fas/FasL信號(hào)通路抑制食管癌腫瘤的進(jìn)展，該過(guò)程能有效地促進(jìn)食管癌小鼠的放療增敏。

Objective To explore the specific mechanisms of rapamycin treating esophageal cancer,and sensitizing radiotherapy through the Fas/FasL signaling pathway. Methods The apoptosis ability of ECA109 cells was evaluated using CCK-8 and flow cytometry.The ECA109 mouse model of esophageal cancer was established using ECA109.C57BL/6J mice were divided into control group,radiation group (4 Gy ¹³⁷Cs γ rays),rapamycin group （rapamycin 1.5 mg/kg）,and radiation+rapamycin (4 Gy ¹³⁷Cs γ rays+rapamycin 1.5 mg/kg).The tumor volume and mass,tumor inhibition rate and growth coefficient,the sensitization effect of radiotherapy and rapamycin were recorded.ELISA kits were used to assess levels of Caspase-3,Bcl-2,and Bax in the tumor.Histological changes in the esophageal cancer of mice were observed using HE staining.Western blotting analysis was performed to evaluate the activation of the Fas/FasL signaling pathway. Results Compared with the radiation group,the tumor volume and mass in the radiation+rapamycin group were significantly reduced （P＜0.001）.Compared with the radiation group,the tumor inhibition rate and TGD in the radiotherapy+rapamycin group were significantly increased,and the TGT3 was significantly prolonged （P＜0.05）.In the radiotherapy+rapamycin group,a large number of tumor cells disintegrated,and interstitial edema was more obvious.Compared with the radiation group,the expression levels of Bcl-2 in the radiation+rapamycin group were significantly decreased,while the expression levels of Bax and Caspase-3 were significantly increased （P＜0.001）.Compared with the radiation group,ECA109 cell viability was significantly decreased in the radiation+rapamycin group （P＜0.001）.After the expression of Fas and FasL was inhibited,the viability of ECA109 cells was significantly increased,and the apoptosis rate of ECA109 cells was significantly decreased （P＜0.001）.Compared with the radiation group,the relative expressions of Fas and FasL proteins in the radiation+rapamycin group were significantly increased （P＜0.001）. Conclusion Rapamycin inhibits the progression of esophageal cancer tumor through the Fas/FasL signaling pathway,which effectively promotes the sensitization of esophageal cancer mice to radiotherapy.

R965

江蘇省衛(wèi)生計(jì)生委科研課題項(xiàng)目(H2017036)