Correlation analysis of mRNA expression and prognosis of hOGG1 gene polymorphism in patients with non-small cell lung cancer

Abstract

Level of mRNA expression and gene polymorphism of human 8-hydroxyguanine glycosidase 1 (hOGG1) in patients with non-small cell lung cancer (NSCLC) were investigated. A polymorphism analysis of hOGG1 gene rs1052133 locus in 182 NSCLC patients (NSCLC group) surgically treated in Xiang Yang No. 1 People's Hospital, Hubei University of Medicine from January 2008 to January 2012 and 200 healthy individuals (control group) was performed. The expression level of hOGG1 was compared between cancer tissues and adjacent tissues of NSCLC patients, and the survival rate was analyzed. The expression level of hOGG1 was significantly higher in cancer tissues than that in adjacent tissues (P<0.001). Taqman probe method was used to detect the genotypes of hOGG1 polymorphism locus rs1052133, with the genotype distribution frequencies of NSCLC group (P=0.411) and control group (P=0.354) consistent with the Hardy-Weinberg equilibrium. The proportion of C/C gene was significantly higher in NSCLC group than that in control group (P=0.008, OR=2.2, 95%, CI=1.27-4.52). The median value of the hOGG1 expression level in detection results as the boundary, NSCLC patients were divided into hOGG1 high expression group (≥3.61) with 91 cases and hOGG1 low expression group (<3.61) with 91 cases. The 1-, 2- and 3-year survival rates of patients in hOGG1 low expression group were significantly higher than those in hOGG1 high expression group (P=0.007). The 3-year survival rate in hOGG1 low expression group is significantly higher than that in hOGG1 high expression group (P=0.007). The sensitivity, specificity and AUC of hOGG1 to patient survival prediction were 83.33%, 64.29%, and 0.816, respectively. In conclusion, hOGG1 is highly expressed in NSCLC tissues. Compared to S/S and S/C genotypes, the C/C gene was found to be more common in NSCLC group than in control group. Thus, hOGG1 has a high predictive value for patient survival.

Keywords: NSCLC; expression level; gene polymorphism; hOGG1; prognosis.

Figure 1.

Comparison of hOGG1 expression between cancer tissues and adjacent tissues of NSCLC patients. The results of RT-qPCR detection showed that the expression level of hOGG1 was 3.61±0.38 in cancer tissues and 1.37±0.25 in adjacent tissues in NSCLC group of patients. That of hOGG1 was significantly higher in cancer tissues than that in adjacent tissues in NSCLC group of patients, with a statistically significant difference (t=68.630, P<0.001). hOGG1, human 8-hydroxyguanine glycosidase 1; NSCLC, non-small cell lung cancer.

Figure 2.

hOGG1 expression and prognosis of NSCLC patients The 1-, 2- and 3-year survival rates of patients in hOGG1 low expression group were 87.91, 70.33 and 63.74%, respectively. Those of patients in hOGG1 high expression group were 79.12, 56.04, and 43.96%, respectively. Those of patients in hOGG1 low expression group were significantly higher than those in hOGG1 high expression group (P=0.007). hOGG1, human 8-hydroxyguanine glycosidase 1; NSCLC, non-small cell lung cancer.

Figure 3.

hOGG1 gene polymorphism and prognosis of NSCLC patients. The 1-, 2- and 3-year survival rates of patients with hOGG1 rs1052133 of S/S+S/C genotypes were 83.10, 52.11, and 45.07%, respectively, and those of patients with C/C genotype were 80.18, 48.65, and 36.04%, respectively, with no significant difference (P=0.365). hOGG1, human 8-hydroxyguanine glycosidase 1; NSCLC, non-small cell lung cancer.

Figure 4.

Predictive value of hOGG1 expression in the survival of patients with NSCLC. The sensitivity, specificity and AUC of hOGG1 in survival prediction were 83.33%, 64.29%, and 0.816, respectively. hOGG1, human 8-hydroxyguanine glycosidase 1; NSCLC, non-small cell lung cancer.