MORC4在结直肠癌中的表达及其对结直肠癌细胞生物学行为的影响

Expression of MORC4 in colorectal cancer and its effects on biological behaviors of colorectal cancer cells

目的探讨染色质重塑蛋白家族CW型锌指结构蛋白4(MORC4)在结直肠癌(CRC)中的表达及其对CRC细胞生物学行为的影响。方法收集2018年1月至2019年2月台州市第一人民医院经手术切除的CRC组织及癌旁组织,选择CRC细胞系(HCT-15、SW480、SW620、DLD-1、HCT116)和人结肠上皮细胞株(NCM460)。采用q RT-PCR方法检测80例CRC组织及其相应的癌旁组织中MORC4 mRNA的表达。采用免疫组化法检测150例CRC组织及60例癌旁组织中MORC4蛋白表达情况,分析MORC4蛋白高表达与患者临床病理特征的关系。绘制Kaplan-Meier生存曲线分析MORC4蛋白表达与CRC患者预后关系。选择MORC4 mRNA表达水平较高的DLD-1细胞为研究对象,构建MORC4敲低细胞DLD-1(敲低组)及空白对照组、阴性对照组,采用细胞增殖/凋亡检测(CCK-8)法、划痕实验及Transwell细胞侵袭实验检测CRC细胞的增殖、迁移及侵袭情况。结果相比癌旁组织,CRC组织中MORC4 mRNA表达水平及MORC蛋白表达率均显著升高(均P<0.05)。不同性别、年龄、肿瘤位置(左右侧)、肿瘤直径、T分期的患者CRC组织MORC4蛋白高表达率比较,差异均无统计学意义(均P>0.05);不同分化程度、淋巴结转移情况、远处转移情况、肿瘤-淋巴结-转移分期及血清癌胚抗原水平的患者CRC组织MORC4高表达率比较,差异均有统计学意义(均P<0.05)。与MORC4低表达患者相比,MORC4高表达患者预后更差(P<0.01)。相比空白对照组和阴性对照组,敲低组细胞24、48、72 h增殖能力均显著降低,迁移能力显著降低,穿基底膜细胞数量明显减少(均P<0.05)。结论CRC患者MORC4表达上调与不良预后相关,MORC4可能是CRC的一个预后标志物,敲低MORC4可抑制CRC细胞增殖、迁移和侵袭。

Objective To investigate the expression of the chromatin remodeling protein microrchidia family CW-type zinc finger 4(MORC4)in colorectal cancer(CRC)and its effects on biological behaviors of CRC cells.Methods The surgically resected cancer tissue and pericancerous tissue samples were collected from CRC patients admitted in the Taizhou First People's Hospital from January 2018 to February 2019.The expression of MORC4 mRNA in 80 CRC tissue and corresponding adjacent tissue samples was detected by qRT-PCR;the expression of MORC4 protein in 150 CRC tissue and 60 pericancerous tissue samples was detected by immunohistochemical method.The correlation between MORC4 protein levels and clinicopathological characteristics of CRC patients was examined.Kaplan-Meier survival curves were generated to analyze the relation between MORC4 expression and the prognosis of CRC patients.For further investigation,MORC4 was knocked down in CRC DLD 1 cells(DLD 1 KD).The proliferation,migration and invasion abilities of DLD 1 KD cell were detected by CCK 8 assay,scratch assay and Transwell assay,respectively;and the results were compared with those of control group(NC group)and negative control group(siRNA group).Results The expression levels of MORC4 mRNA and protein in CRC tissues were significantly higher than those of adjacent non-cancerous tissues(P<0.05).There were no significant differences in positive expression rate of MORC4 among patients with differing gender,age,tumor location(left and right sides),tumor diameter and T stage(all P>0.05).However,the MORC4 expression rate was correlated with differentiation degree,lymph node metastasis,distant metastasis,TNM stage and serum CEA levels(all P<0.05).The prognosis of patients with high MORC4 expression was poorer than those with low MORC4 expression(P<0.01).The cell proliferation ability of DLD-1 KD cells was lower than that of NC and siRNA groups at 24,48,and 72 h(all P<0.05);the migratory potential and the count of cells infiltrating the basement membrane of DLD-1 KD cells were lower than those of NC and siRNA groups at 48 h(all P<0.05).Conclusion Elevated MORC4 levels in CRC patients are associated with an unfavorable prognosis,and down regulated MORC4 expression can inhibit the proliferation,migration and invasion in CRC cells.