GLUT1 expression in patients with non-small cell lung cancer and its impact on survival

Abstract

GLUT1 is an essential glucose transporter, the expression of which increases in tumor cells, especially under conditions of hypoxia, and correlates with their active proliferation. This study aimed to investigate the relationship between GLUT1 expression and biological parameters and to evaluate the potential impact on survival in patients with radically treated non-small cell lung cancer (NSCLC). Forty-two patients who received radical treatment for NSCLC were involved in the study. Gender, age, smoking history, disease stage, and tumor histological type were considered when analyzing the data. GLUT1 antibodies were used to assess the degree of hypoxia. A semi-quantitative immunohistochemical score ranging from 0 to 12 was used for calculation. The chi2 and Student's t-test were used to compare categorical and parametric variables. The Cox proportional hazards model, the Kaplan-Meier method, and the Log-rank test were used to evaluate the effect of GLUT1 expression on survival. The results were considered statistically significant at p<0.05. A moderate correlation was found between GLUT1 expression and histological type of NSCLC (r=0.432, p<0.0001), sex (r=0.336, p<0.0009), and smoking (r=0.325, p<0.0009). GLUT1 overexpression was observed more in squamous cell carcinomas than in adenocarcinomas (p=0.0001). In patients with adenocarcinomas, the level of GLUT1 expression depended on age and T category. In patients with squamous cell carcinomas, GLUT1 expression was not associated with the studied clinicopathological characteristics. Patients with T1b-2a categories, without regional lymph node metastases, younger than 60, and non-smokers have better survival. Kaplan-Meier curves demonstrated no statistically significant differences in recurrence-free survival and overall survival between the patients with high and low GLUT1 (Log-rank p=0.3284 and Log-rank p=0.7161, respectively). In conclusion, GLUT1 overexpression is associated with squamous cell lung carcinomas. GLUT1 expression has no prognostic value and does not correlate with recurrence-free and overall survival in radically treated patients with NSCLC.