CXCR4 and colorectal cancer: The human renal cellcarcinoma tumor samples that are analyzed revealed varying intensities of CXCR4 expression ranging from weak tostrong, as previously described for pancreatic and colorectal cancer [38].Interestingly, CXCR4 expression was downregulated in 34% and upregulatedin 24% of renal cell carcinoma as compared to original tubuli cells.