Protein tyrosine phosphatase non-receptor type 18 (PTPN18) is often highly expressed in colorectal cancer (CRC)

but its role in this disease remains unclear. We demonstrated that PTPN18 overexpression promotes growth and tumorigenesis in CRC cells and that PTPN18 deficiency yields the opposite results

in vitro

. Moreover

a xenograft assay showed that PTPN18 deficiency significantly inhibited tumorigenesis

in vivo

. PTPN18 activated the MYC signaling pathway and enhanced CDK4 expression

which is tightly associated with the cell cycle and proliferation in cancer cells. Finally

we found that MYC interacted with PTPN18 and increased the protein level of MYC. In conclusion

our results suggest that PTPN18 promotes CRC development by stabilizing the MYC protein level

which in turn activates the MYC-CDK4 axis. Thus

PTPN18 could be a novel therapeutic target in the future.