CD44和CD24在鼻咽癌细胞系HK-1中调控STAT3发生磷酸化的分子机制研究

摘要

Objective To study the mechanism of CD44 and CD24 in the regulation of STAT3 phosphorylation in HK-cells to promote the development of nasopharyngeal carcinoma.Methods Flow cytometry was used to sort on Cultured Nasopharyngeal Carcinoma HK-1 NPC cells for CD44 +/CD24 + HK1 cells and CD44-/CD24-HK1 cells.,Western blot,MTT assay and tumor microsphere formation experiments Were conducted for the analysis of nasopharyngeal carcinoma P-STAT3 positive tumor cells,to detect the expression of STAT3,and after it was inhibited after static silencing,the effects on forming ability CD44 +/CD24 + HK1 cells proliferation and tumor spheres.Results In nasopharyngeal carcinoma HK-1 cells,we can extract 34.7％ CD44+/CD24 + HK1 cells and 41.5％ CD44-/CD24-cells,CD44+/CD24 + HK1 cells relative to CD44-/CD24-HK1 cells,it expressed high levels of STAT3.Stattic phosphorylation inhibitor of STAT3 can inhibit the expression of phosphorylated STAT3 in CD44 +/CD24 + and CD44-/CD24-HK1 cells.MTT showed stattic of 16μmol/L significantly inhibited CD44+/CD24+ HK 1 and CD44-/CD24-cell proliferation.Tumor microspheres formation experiment showed that Stattic can significantly inhibit the formation of HK1 CD44+/CD24+ and CD44-/CD24-cell microspheres,indicating that STAT3 plays important roles for HK1 CD44 +/CD24 + cell proliferation and nasopharyngeal carcinoma.Conclusion CD44 and CD24 are expressed in nasopharyngeal carcinoma HK-1 cells in the side population cells,CD44 +/CD24 + positive cells can increase STAT3 phosphorylation to promote the development of nasopharyngeal carcinoma,and provides a new target for the treatment of nasopharyngeal carcinoma by targeting cancer stem cells.Clinical treatment can inhibit the expression of STAT3,thereby inhibiting the formation of tumor cells proliferation and CD44 +/CD24 + HK1 microspheres leading to reducing the incidence of nasopharyngeal carcinoma.%目的 研究CD44和CD24在鼻咽癌细胞系HK-1中调控STAT3发生磷酸化的分子机制.方法 采用流式细胞仪对培养的鼻咽癌HK-1高分化NPC细胞进行分选以获得CD44 +/CD24+ HK1细胞及CD44-/CD24-HK1细胞,通过Western blot、MTT和肿瘤微球形成等实验,分析鼻咽癌阳性肿瘤细胞中P-STAT3的表达,以及STAT3被抑制剂Stattic沉默后,对CD44+/CD24+ HK1和CD44-/CD24-HK1细胞增值能力和肿瘤微球形成能力的影响.结果 鼻咽癌HK-1细胞中可以提取到34.7％的CD44 +/CD24+ HK1细胞和41.5％的CD44-/CD24-HK1细胞,CD44+/CD24+ HK1细胞比CD44 /CD24-HK1细胞表达磷酸化STAT3水平高.STAT3的抑制剂Stattic可以抑制CD44+/CD24+ HK1和CD44-/CD24-HK1细胞磷酸化STAT3的表达,MTT实验显示16μmol/L Stattic明显抑制CD44+/CD24+ HK1和CD44-/CD24-HK1细胞增殖,肿瘤微球形成实验表明Stattic可明显抑制CD44+/CD24+ HK1和CD44-/CD24-HK1细胞微球形成能力,即STAT3在CD44+/CD24+ HK1细胞增殖和鼻咽癌进程中发挥重要的作用.结论 CD44和CD24在鼻咽癌侧群细胞HK-1细胞中,CD44 +/CD24+阳性细胞通过诱导STAT3发生磷酸化来促进鼻咽癌发展,为鼻咽癌肿瘤干细胞的靶向治疗提供了新的靶点,临床治疗可靶向抑制STAT3的表达,从而抑制CD44+/CD24+ HK1细胞增殖和肿瘤微球的形成,最终达到降低鼻咽癌的发生率.