The AGR2 mRNA levels were negatively correlated with XBP1 protein levels in HCC (Spearman: − 0.169, p value: 0.02) in the TCGA, Pancancer microarray dataset and in lung squamous cell carcinoma (Spearman: − 0.16, p value: 3.65e-3). This evidence concerns the gene XBP1 and hepatocellular carcinoma.