mRNA expressions of hTERT and MMP-7 in the peripheral blood of patients with colorectal cancer and their correlation / 肿瘤研究与临床

ABSTRACT

Objective To detect the expressions of hTERT and MMP-7 mRNA in the peripheral blood of patients with colorectal cancer and their correlation,and discuss the clinical significance of peripheral blood micro-metastasis.Methods Total RNA was extracted from blood samples by TRIzol and was reverse transcribed into cDNA.The mRNA expressions of MMP-7 and hTERT were detected by real-time PCR.Results Positive mRNA expression of hTERT was found in 63 of 181 patients with colorectal cancer,while positive mRNA expression of MMP-7 was seen in 61 cases.The positive rates of hTERT and MMP-7 mRNA had no significant differences in the patients' sex and age (P ＞ 0.05).The positive rate of MMP-7 mRNA in the patients with poorly differentiated adenocarcinoma (43.9 ％) was higher than that in the patients with moderately and well differentiated adenocarcinoma (27.8 ％) (x2 =4.873,P ＜ 0.05).The positive rate of HTERT mRNA in the patients with stage Ⅲ-Ⅳ (42.5 ％) was higher than that in the patients with stage Ⅰ-Ⅱ (24.0 ％) (x2 =6.591,P ＜ 0.05).The positive rate of MMP-7 mRNA in the patients with stage Ⅲ-Ⅳ (39.6 ％) was higher than that in the patients with stage Ⅰ-1Ⅱ (25.3 ％) (x2 =4.014,P ＜ 0.05).The positive rate of hTERT mRNA in the patients with distant metastasis (53.3 ％) was higher than that in the patients without distant metastasis (28.7 ％) (x2 =9.059,P ＜ 0.05).The positive rate of MMP-7 mRNA in the patients with distant metastasis(46.7 ％) was higher than that in the patients without distant metastasis (29.4 ％) (x2 =4.506,P ＜ 0.05).The positive rate of hTERT mRNA in the patients with positive CEA expression (52.6 ％) was significantly higher than that in the patients with negative CEA expression (30.1％) (x2 =6.735,P ＜ 0.05).The positive rate of MMP-7mRNA in the patients with positive CEA expression (60.5 ％) was significantly higher than those in the patients with negative CEA expression (26.6 ％) (x2 =15.490,P ＜ 0.05).In the patients without distant metastasis,any of hTERT and MMP-7 mRNA expression was thought to be blood micro-metastasis.The recurrence and metastasis rates after 6 months in the patients with blood micrometastasis (36.58 ％) were higher than those in the patients without blood micro-metastasis (7.14 ％)(x2 =13.027,P ＜ 0.05).The recurrence and metastasis rates after 12-month follow-up in the patients with blood micro-metastasis (68.29 ％) were higher than those in the patients without blood micro-metastasis (12.5 ％) (x2 =31.948,P ＜ 0.01).The sensitivity of combined detection was 80.00 ％,and the specificity was 79.03 ％ after 12-month follow-up.Spearman correlation analysis revealed that significant positive correlation existed between hTERT and MMP-7mRNA expression (r =0.341,P =0.000).Conclusion Detection of hTERT and MMP-7 mRNA expression can be used as reliable markers to predict peripheral blood micrometastasis in colorectal cancer patients.