微小RNA-429在人胃癌前病变组织的表达

Expression of microRNA- 429 in gastric precancerous lesions

目的探讨微小RNA（miRNA，miR）-429在人胃癌前病变中的表达及其作用。方法采用实时定量聚合酶链反应（PCR）技术检测50例胃癌组织、60例慢性萎缩性胃炎组织以及60例正常胃组织中miR-429表达水平；采用肿瘤坏死因子-α（TNF-α）诱导人胃黏膜上皮细胞株（GES-1）转化成胃癌前病变（PLGC）细胞模型，利用包装好的miR-429慢病毒以及慢病毒阴性对照感染PLGC细胞，细胞计数试剂盒（CCK-8）法检测PLGC细胞的增殖，通过Targetscan预测miR-429的靶基因，Western blot检测靶基因的表达水平。结果54例（90.0%，54/60）慢性萎缩性胃炎组织中miR-429的表达量较正常胃组织下调，其中37例（61.7%，37/60）下降2倍以上，伴有肠上皮化生、不典型增生者表达量降低更为显著（P＝0.012）。所有胃癌组织中miR-429的表达量均低于正常胃组织及慢性萎缩性胃炎组织（均P＝0.003），且与肿瘤有无淋巴结转移、癌旁血管浸润及TNM分期呈负相关。转染miR-429后5 d，PLGC细胞生长明显受抑，转染组吸光度值（0.852±0.023）明显低于对照组（1.488±0.031，P＝0.000）。转染组CDC25B（通过Targetscan发现的miR-429靶基因）蛋白表达较对照组明显降低。结论miR-429在慢性萎缩性胃炎组织、胃癌组织中表达均明显低于正常胃组织，具有抑制胃癌前病变发展、影响胃癌侵袭转移的作用。

Objective To investigate the expression and function of microRNA （miRNA, miR） -429 in human gastric precancerous lesions. Methods The expression of miR -429 in gastric cancer tissues （n = 50 ）, gastric tissues with chronic atrophic gastritis （n = 60） and normal gastric tissues （n =60） was detected by real -time quantitative polymerase chain reaction （PCR）. Human Gastric Epithelial cell strain - 1 （ GES - 1 ） was transformed into gastric cancer precancerous lesion （PLGC） cell model by tumor necrosis factor - （x （ TNF - ct ）. PLGC cells were detected by cell counting kit - 8 （CCK- 8 ） method using the miR -429 lentivirus and lentivirus negative control. The target gene of miR -429 was predicted by targetscan, and the expression level of target gene was deteceted by Western blotting. Results The expression of miR -429 in gastric tissue of 54 patients （90% , 54/60） with chronic atrophic gastritis was lower than that of normal gastric tissue, of which 37 cases （ 61.7%, 37/60） de- creased more than 2 times. What＇ s more, the expression of miR -429 in the chronic atrophic gastric tis- sues with metaplasia and atypical byperplasia was statistically much more significant （P = 0. 012）. The ex- pression of miR -429 in all gastric cancer tissues was lower than that in normal gastric tissues and chronic atrophic gastric tissues （ all P = 0. 003 ） , and the expression level was negatively correlated with lymph node metastasis, adjacent vascular invasion and TNM staging. The growth of PLGC cells was siguificantly inhibited at 5th day after transfeetion with miR-429, and the absorbance （0. 852 -0. 023 ） was significantly reduced as compared with the control group （1. 488 ± 0. 031, P = 0. 000）. The expression of CDC25B in the transfection group （the target gene of miR- 429 found by targetscan） was siguificantly low- er than that of control group. Conclusion The expression of miR -429 in the gastric tissue of chronic a- trophic gastritis and gastric cancer tissues was significantly down - regulated, and it could inhibit the development of gastric precancerous lesions to gastric cancer and the invasion and metastasis of gastric cancer. CDC25B might be the target gene of miR -429.