Western blot and RT-PCR results indicated that the expressions of XRCC5 and COX-2 were positively correlated at both protein and mRNA levels, as shown in Fig 1C and 1D.The above results indicated that XRCC5 was a COX-2 promoter-binding protein in colon cancer cells. This evidence concerns the gene XRCC5 and malignant colon neoplasm.