CHRDL2 promotes cell proliferation by activating the YAP/TAZ signaling pathway in gastric cancer

The encoding product of Chordin-like 2 (CHRDL2) is a member of the chordin family of proteins, which has been shown to be aberrantly expressed in several types of solid tumors. The regulatory underlying mechanisms of CHRDL2, however, remain poorly understood in gastric cancer (GC). In the present study, we determined that CHRDL2 was abnormally upregulated in human gastric cancer tissues compared with adjacent normal tissues. We also showed that CHRDL2 was positively associated with T stage, the pathological stage, distant metastasis, and poor patient prognosis. Furthermore, the serum level of CHRDL2 was obviously higher in GC patients than normal people, and is positively correlated with later TNM stage, deeper T stage, later N stage and poorer differentiation. Moreover, we verified that overexpressing CHRDL2 promoted the proliferation and cell cycle transition of GC cells both in vitro and in vivo, whereas the opposite results were observed in CHRDL2-depleted cells. In addition, the phosphorylation levels of Yes-associated protein (YAP), transcriptional coactivator with PDZ-binding motif (TAZ) and the total levels MST2 were decreased in CHRDL2 overexpressing cells. Consistent with previous findings, we observed the converse results in CHRDL2-silenced GC cells. Additionally, knockdown of YAP and overexpression of STK3 (MST2) could reverse the effects of CHRDL2 overexpression-induced proliferation of GC cells in vitro. Taken together, CHRDL2 plays a key role by activating the YAP/TAZ pathway in gastric cancer. Therefore, CHRDL2 could serve as a potential therapeutic tool for the treatment of gastric cancer.