In addition to differential orchestration of many cancer hallmarks in tumors of the colon and rectum, these disturbed oncogenic signaling pathways also controlled the expression or stability of a major transcriptional inducer of CA9, hypoxia-inducible factor (HIF) 38-40, thereby leading to the fluctuations of local CA9 levels within CRC tumor microenvironment. Here, CA9 is linked to colorectal carcinoma.