However, the role of plexin B1 remains controversial because in various cancers, both tumor-promoting and tumor-suppressing effects have been observed.278–280 A recent study found that a newly identified gene, MACC1 (metastasis-associated in colon cancer 1), has high potential to be a key regulator of MET expression and further influence CRC progression and metastasis.281 Elevated levels of MACC1 expression were found in both local and metastatic malignant tissues. This evidence concerns the gene MACC1 and colorectal carcinoma.