口腔鳞癌中miR-661的表达及其与增殖、凋亡的关系研究

Expression of miR-661 and Its Effects on Proliferation and Apoptosis of Oral Squamous Cell Carcinoma

目的检测口腔鳞癌中miR-661的表达,探讨其与细胞增殖和凋亡的相关性。方法收集我院收治的口腔鳞癌手术患者51例,留取肿瘤组织和距肿瘤边缘>2 cm的远端组织进行研究。采用实时荧光定量PCR检测肿瘤组织和远端组织中miR-661的表达;免疫组化法检测肿瘤组织中Ki67、Bcl-2和Bax的表达;Western blotting检测肿瘤组织中PCNA的表达。选择口腔鳞癌HSC-4细胞系,建立无关序列组(NC组)和miR-661 inhibitor组,通过集落形成实验观察细胞的克隆形成情况,Western blotting检测两组细胞中Ki67、PCNA、Bcl-2、Caspase-9和Bax的表达。结果肿瘤组织中miR-661的表达水平显著高于远端组织(P<0.05),其表达与肿瘤最大径、脉管累犯、淋巴结转移和TNM分期有明显相关性(P<0.05),而与性别、年龄、分化程度和炎症细胞浸润程度无明显相关性(P>0.05);此外,miR-661的表达与患者生存时间有明显相关性(P<0.05);进一步分析显示,miR-661与Ki67增殖指数、Bcl-2及PCNA表达水平均呈正相关(P<0.05),与Bax表达水平呈负相关(P<0.05)。与NC组相比,miR-661 inhibitor组细胞中Ki67、PCNA和Bcl-2表达均显著下调,克隆形成明显减少,Caspase-9、Bax表达均明显上调。结论 miR-661在口腔鳞癌中表达显著上调,可能与肿瘤的形成和进展有关,miR-661可能通过调节细胞的增殖和凋亡发挥作用,其表达水平可能与患者预后相关。

Objective To detect the expression of miR-661 in oral squamous cell carcinoma, and to explore its correlation with cell proliferation and apoptosis. Methods A total of 51 patients with oral squamous cell carcinoma hospitalized in our hospital for surgical treatment were collected. Their tumor tissues and the distal tissues more than 2 cm away from the margin of tumors were retained and studied. The expressions of miR-661 in tumor tissues and distal tissues were detected by real-time quantitative PCR. The expressions of Ki67, Bcl-2 and Bax in tumor tissues were detected by immunohistochemistry. The PCNA expression in tumor tissues was detected by Western blotting. Human oral squamous cell carcinoma HSC-4 cell line was selected to establish the unrelated sequence group(NC group) and miR-661 inhibitor group, and cell proliferation was observed by colony-forming assay. The expressions of Ki67, PCNA, Bcl-2, Caspase-9 and Bax were detected by Western blotting. Results The expression of miR-661 was significantly higher in tumor tissues than in distal tissues(P<0.05). The expression of miR-661 was correlated with the maximum diameter of tumor, vascular invasion, lymph node metastasis and TNM stage(P<0.05), but had no relation with the sex, age, degrees of differentiation and inflammatory cell infiltration(P>0.05). Survival analysis showed that the expression of miR-661 was related to the survival time(P<0.05). The correlation analysis showed that the expression of miR-661 was positively correlated with the Ki67 proliferation index and Bcl-2 expression(P<0.05), but was negatively correlated with Bax expression(P<0.05). It was also positively correlated with PCNA expression(P<0.05). Compared with NC group, expressions of Ki67, PCNA and Bcl-2 were down-regulated in miR-661 inhibitor group, while the expression of Caspase-9 and Bax were up-regulated. Cell clone formation was reduced in miR-661 inhibitor group. Conclusion The expression of miR-661 is significantly increased in oral squamous cell carcinoma, and its up-regulation may be related to the formation and progression of tumor lesions. MiR-661 may play a role in regulating cell proliferation and apoptosis. Detection of the expression of miR-661 may be related to the prognosis.