CTSD and colorectal carcinoma: The enhanced expression of KLF4, SERPINB5, DGKA, S100A10, TOB1, BAIAP2, CDKN2B, and CTSD was validated by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) using three CRC cell lines: HCT116, LS174T, and LoVo (Fig. 2I–K).