胃癌患者外周血人端粒酶反转录酶基质金属蛋白酶-7mRNA的表达及临床意义

摘要

目的 应用实时荧光定量聚合酶链反应(RT-PCR)法检测胃癌患者外周血中人端粒酶反转录酶(HTERT)及基质金属蛋白酶(MMP)-7 mRNA 的表达情况,探讨其对监测胃癌血液微转移的临床意义及其对预后的影响.方法 采用Trizol法提取血液标本中的总RNA,将其反转录成cDNA,然后用RT-PCR技术检测血液标本中MMP-7 mRNA和HTERT mRNA表达,计算样本的△Ct值.结果 126例胃癌患者中,HTERT mRNA阳性58例,阴性68例.MMP-7 mRNA阳性46例,阴性80例.不同性别、年龄、分化程度的胃癌患者外周血HTERT、MMP-7 mRNA阳性率差异无统计学意义.Ⅲ、Ⅳ期患者外周血HTERT mRNA阳性率较Ⅰ、Ⅱ期患者明显增高,差异有统计学意义.有远处转移的胃癌患者较无远处转移的患者外周血HTERT、MMP-7 mRNA阳性率明显增高,差异有统计学意义.癌胚抗原阳性患者外周血HTERT、MMP-7 mRNA阳性率较癌胚抗原阴性的患者明显增高,差异有统计学意义.无远处转移的胃癌患者中,HTERT、MMP-7阳性与阴性患者复发转移情况比较,检测后6、12个月HTERT阳性组较阴性组肿瘤复发转移率显著增高,差异有统计学意义.检测后12个月MMP-7阳性组较阴性组肿瘤复发转移率增高,差异有统计学意义.结论 胃癌患者外周血HTERT及MMP-7 mRNA表达对早期发现血液微转移及预后具有重要意义,值得进一步研究.%Objective To determine the expression of peripheral blood human Lelomerase reverse tr arise riptase (HTERT) and matrix metalloproteinase-7 (MMP-7) mRNA in patients with gastric cancer via real-time polymerase chain reaction (RT-PCR) for studying the clinical significance of blood micrometastasis and its impact on the prognosis. Methods Total RNA was extracted from blood samples by using Trizol and was reversely transcribed into cD-NA. This was followed by detection of MMP-7 and HTERT mRNA expression via PT-PCR for further computation of ΔCt. Results Of 126 patients with gastric cancer. 58 cases tested positive and 68 remaining cases proved negative for HTERT mRNA. There were 46 positive cases and 80 negative cases for MMP-7 mRNA. The distinction in gender, age or grade of differentiation did not produce statistical significance (all P＞0.05) in the positive rates of peripheral blood HTERT and IV1MP-7 mRNA. Patients with stage Ⅲ-Ⅳ were noted as having significantly higher positive rate of HTERT mRNA than those with stage I -II (P＜0.05). Higher positive rates of HTERT and MMP-7 mRNA were shown in patients with distal metastasis than those without. (P＜0.05). In addition, patients whose CEA tested positive were associated with higher positive rates of HTERT and MMP 7 mRNA compared with those showing lack of evidence of serum CEA (P＜0.05). Of all patients without distal metastasis, patients with positive HTERT mRNA expression yielded considerably higher rates (both P＜0.05) of tumor relapse and metastasis at months 6 and 12 as compared with those as having negative expression. Furthermore, higher rate of tumor relapse and metastasis at month 12 (P＜0.05) was found in patients with positive, but not negative expression of MMP 7 mRNA. Conclusion Detection of peripheral blood MMP 7 and HTERT mRNA expression in patients with gastric cancer may have shed light on early diagnosis of blood micrometastasis and judgment of prognosis and therefore deserves further studies.