CLDN2 and colorectal carcinoma: Downregulated mRNAs are presented as blue dots on the volcano plot which include CA1, CD177, TMIGD1, ZG16, GUCA2A, CLCA1 and CLCA4. Figure 1c,d show the top 5 upregulated mRNAs (MMP3, CLDN2, S100P, KRT17 and CST1) and top five downregulated mRNAs (CLCA1, CA1, SLC26A3, GUCA2A and ZG16) in CRC vs NT based on RNA-Seq analysis (log2 TPM).