Background & objective: Recent researches have revealed that chemokine-chemokine receptor network plays an important role in tumor metastasis. This study was to investigate the expression of CXCR3, a chemokine receptor, and its correlation to clinicopathologic features of hepatocellular carcinoma (HCC).
Methods: CXCR3 mRNA expression in 7 human HCC cell lines, 18 normal liver tissues and 64 pairs of HCC tissues and adjacent liver tissues was detected by reverse transcription-polymerase chain reaction (RT-PCR) and real-time quantitative PCR; CXCR3 protein expression was detected by immunohistochemistry. The correlation of CXCR3 expression to the metastasis of HCC was analyzed.
Results: CXCR3 mRNA was expressed in 2 HCC cell lines (MHCC97-H and MHCC97-L) with metastatic potential, but not in 5 HCC cell lines without metastatic potential. The CXCR3/beta2M expression ratio in MHCC97-H cells (high metastatic potential) was 33.0x10(-4), and that in MHCC97-L cells (low metastatic potential) was 8.7x10(-4). Strong staining of CXCR3 protein in MHCC97-H and MHCC97-L cells was observed. However, the staining of CXCR3 protein was not detected in 4 HCC cell lines without metastatic potential; only weak staining was detected in HepG-2 cells. The expression of CXCR3 protein in HCC is significantly correlated to the invasiveness of tumors (P=0.003). The 1-and 2-year tumor-free survival rates of the HCC patients with strong positive CXCR3 expression were significantly lower than those of the patients with weak positive CXCR3 expression (66.7% vs. 75.0%, 31.3% vs. 59.5%, P=0.044).
Conclusion: The expression of CXCR3 might play a role in the invasion and metastasis of HCC.