XRCC1 and carcinoma: Moreover, we examined XRCC1 mRNA expression in normal pancreatic tissue and pancreatic cancer (PAAD) tissues by interrogating 167 samples (GTEx normal), 4 tumor-adjacent tissues (TCGA), 179 carcinoma samples (TCGA) and the results showed that XRCC1 mRNA expression was significantly elevated in PAAD tissues relative to associated normal pancreatic tissue (Fig. 2B).