Expression of CXCR4 and VEGF‐C is correlated with lymph node metastasis in non‐small cell lung cancer

BACKGROUND This study investigated the correlations between CXCR4 and VEGF-C expression and lymph node metastasis in non-small cell lung cancer (NSCLC). METHODS Tumor specimens, lymph nodes, and normal lung tissues were obtained from 110 NSCLC patients who underwent complete resection. Quantitative reverse transcription-PCR and immunohistochemistry assays were conducted to evaluate messenger RNA (mRNA) and protein expression of CXCR4 and VEGF-C. Logistic regression analysis was performed to determine the independent risk factors for lymph node metastasis in NSCLC. RESULTS CXCR4 and VEGF-C mRNA expression were observed in 78 (70.9%) and 64 (58.2%) lung cancer tissues, while CXCR4 and VEGF-C protein expression were observed in 76 (69.9%) and 58 (52.7%) lung cancer tissues, respectively. The expression rates of CXCR4 and VEGF-C mRNA in metastatic lymph nodes were 84.8% and 66.7%, which were higher than that in non-metastatic lymph nodes (27.3% and 18.2%), respectively. Logistic regression analysis revealed that positive expressions of CXCR4 and VEGF-C mRNA were independent risk factors for lymph node metastasis in NSCLC. Furthermore, combined expression of CXCR4 and VEGF-C showed a much higher odds ratio than CXCR4 or VEGF-C expression alone. CONCLUSIONS CXCR4 and VEGF-C were highly expressed in lung cancer tissues and metastatic lymph nodes. CXCR4 and VEGF-C expression levels were significantly correlated with lymph node metastasis in NSCLC. CXCR4 and VEGF-C might synergically promote lymphatic metastasis in lung cancer and might be a clinical predictor of lymph node metastasis in NSCLC patients.