The association of CXCR3 and renal cell carcinoma metastasis

Renal cell carcinoma expresses CXCR3 but the function of CXCR3 in renal cell carcinoma has not been clarified. We explored the function of CXCR3 in renal cell carcinoma and investigated CXCR3 regulating factors.

We obtained 56 clinical samples of clear cell renal cell carcinoma and corresponding normal renal tissue samples from the surgical specimens of Japanese patients who underwent radical nephrectomy at Chiba University Hospital between 2000 and 2011. As renal cell carcinoma cell lines, we used 786-O, ACHN and Caki-1. The expression profiles of CXCR3 and its splice variants were examined. For functional analyses 786-O and interferon-γ inducible 10 kDa protein or IP-10 (CXCL10) were selected as representatives.

CXCR3 and its ligands were abundant in renal cell carcinoma samples compared to corresponding normal kidney samples. The CXCR3-A-to-CXCR3-B ratio was 1.5 times higher in renal cell carcinoma samples than in normal kidney samples. CXCL10 treatment induced 786-O cell migration and invasion, and these effects were inhibited by neutralizing antibody. Phosphorylated RhoA and pro/active matrix metalloproteinase-9 expression was up-regulated by CXCL10 treatment. In clinical samples CXCR3 and CXCR3-A expression was significantly higher in metastatic than in nonmetastatic carcinoma samples. Finally, the expression of CXCR3-A and HIF-1α correlated significantly in clinical samples. In 786-O treatment with CoCl2 up-regulated CXCR3 and HIF-1α expression 4.5 and 2.2-fold, respectively.

We determined the association of CXCR3 and renal cell carcinoma metastasis. CXCR3 expression may be regulated by hypoxia.