CAJ | 학술논문

目的:探讨重组人生长激素(rhGH)对结肠直肠癌细胞株放疗敏感性的影响,并研究其与细胞凋亡的关系.方法:应用流式细胞术及免疫荧光法检测9个人结肠直肠癌细胞株表面生长激素受体(GHR)的表达水平;应用克隆形成实验检测结肠直肠癌细胞经照射后的增殖能力,从而评估其放疗敏感性;应用流式细胞术(Annexin V-FITC染色)检测放疗诱导的细胞凋亡;应用Western blot方法检测rhGH干预后Akt磷酸化水平的变化.结果:从9个细胞株中选择HCT-8为GHR阳性表达细胞,LoVo细胞为阴性表达对照.rhGH显著提高了GHR阳性表达的HCT-8细胞经放疗后的克隆形成率[在高剂量8 Gy照射下尤为明显,(52.1±2.9)%比(21.0±2.7)%,P<0.001],同时减少了细胞凋亡(P<0.05);而对GHR阴性表达的LoVo细胞作用不明显(P>0.05).rhGH能诱导HCT-8细胞Akt快速磷酸化,呈PI-3K依赖(P<0.001).结论:rhGH使GHR阳性表达的结肠直肠癌细胞对放疗有抵抗作用,这种作用可能与其减少细胞凋亡有关.
목적:탐토중조인생장격소(rhGH)대결장직장암세포주방료민감성적영향,병연구기여세포조망적관계.방법:응용류식세포술급면역형광법검측9개인결장직장암세포주표면생장격소수체(GHR)적표체수평;응용극륭형성실험검측결장직장암세포경조사후적증식능력,종이평고기방료민감성;응용류식세포술(Annexin V-FITC염색)검측방료유도적세포조망;응용Western blot방법검측rhGH간예후Akt린산화수평적변화.결과:종9개세포주중선택HCT-8위GHR양성표체세포,LoVo세포위음성표체대조.rhGH현저제고료GHR양성표체적HCT-8세포경방료후적극륭형성솔[재고제량8 Gy조사하우위명현,(52.1±2.9)%비(21.0±2.7)%,P<0.001],동시감소료세포조망(P<0.05);이대GHR음성표체적LoVo세포작용불명현(P>0.05).rhGH능유도HCT-8세포Akt쾌속린산화,정PI-3K의뢰(P<0.001).결론:rhGH사GHR양성표체적결장직장암세포대방료유저항작용,저충작용가능여기감소세포조망유관.
Objective To test the effect of recombinant human growth hormone (rhGH) on the radiotherapy sensitivity of colorectal cancer cell line, and to explore its relationship with apoptosis. Methods Flow cytometry and immunofluorescence were used to detect growth hormone receptor(GHR) expression on 9 human colorectal cancer cell lines. The colony forming assay was performed to measure the post-radiotherapy colorectal cancer cell proliferation as an indicator of radiotherapy sensitivity. Flow cytometry (Annexin V-FITC staining) was used to detect the radiotherapy induced apoptosis; Westem blot was performed to detect the phosphorylated Akt level within the same cell lines. Results HCT-8 GHR positive expression cell and LoVo GHR negative expression cells were selected for further studies. The colony formation rate was significantly enhanced in HCT-8 cells pre-incubated with thGH as compared to the radiotherapy group ceUs and in a dose dependent manne(0-100 mg/L); under high doses (8 Gy), this effect was more dramatic (52.1±2.9 vs 21.0±2.7, P<0.001). thGH pre-incubation also reduced radiotherapy induced HCT-8 cell apoptosis (P<0.05). When GHR was blocked with neutralizing antibodies, this protective effect was eliminated. By contrast, thGH pre-incubation did not change the colony formation rate in GHR negative expression LoVo cells. GH rapidly induced Akt phosphorylation in HCT-8 cells by GH/GHR signaling, and this effect was blocked by PI-3 kinase inhibitor. Conclusions The protective effect of GH on colorectal cancer cells may occur after radiotherapy exposured by GHR, which is related to the reduction of apotosis.