Yes-associated protein 1 exhibits oncogenic property in gastric cancer and its nuclear accumulation associates with poor prognosis.

Yes-associated protein 1 (YAP1) is a multifunctional protein that can interact with different transcription factors to activate gene expression. The role of YAP1 in tumorigenesis is unclear. We aimed to investigate the functional role of YAP1 in tumorigenesis of gastric cancer. YAP1 expression in gastric adenocarcinoma was evaluated. The biological function was determined by proliferation assay, colony formation, cell invasion, and flow cytometric analysis through knocking down or ectopic expressing YAP1 in gastric cancer cell lines coupled with in vivo study. The possible downstream effectors of YAP1 were investigated by expression microarray. YAP1 protein expression was upregulated in gastric cancer. Nuclear accumulation of YAP1 was associated with poor disease-specific survival (P = 0.021), especially in patients with early-stage diseases (P < 0.001). Knockdown YAP1 resulted in a significant reduction in proliferation, anchorage-dependent colony formation, cell invasion, and cell motility. Ectopic YAP1 expression promoted anchorage-independent colony formation, induced a more invasive phenotype, and accelerated cell growth both in vitro and in vivo. Microarray analysis highlighted the alteration of MAPK (mitogen-activated protein kinase) pathway by YAP1. We confirmed a constitutive activation of RAF/MEK/ERK (extracellular signal-regulated kinase) in YAP1-expressing MKN45 cells and further showed that YAP1 enhanced serum/epidermal growth factor-induced c-Fos expression in gastric cancer cells. Our findings supported that YAP1 exhibits oncogenic property in gastric cancer. We provided the first evidence that YAP1 exerted the oncogenic function by enhancing the capacity to activate the early-response gene pathway. YAP1 could be a prognostic biomarker and potential therapeutic target for gastric cancer.

Kang W ，Tong JH ，Chan AW ，Lee TL ，Lung RW ，Leung PP ，So KK ，Wu K ，Fan D ，Yu J ，Sung JJ ，To KF ... -  《-》

YAP1 enhances cell proliferation, migration, and invasion of gastric cancer in vitro and in vivo.

Sun D ，Li X ，He Y ，Li W ，Wang Y ，Wang H ，Jiang S ，Xin Y ... -  《Oncotarget》

miR-375 is involved in Hippo pathway by targeting YAP1/TEAD4-CTGF axis in gastric carcinogenesis.

Kang W ，Huang T ，Zhou Y ，Zhang J ，Lung RWM ，Tong JHM ，Chan AWH ，Zhang B ，Wong CC ，Wu F ，Dong Y ，Wang S ，Yang W ，Pan Y ，Chak WP ，Cheung AHK ，Pang JCS ，Yu J ，Cheng ASL ，To KF ... -  《Cell Death & Disease》

The transcription factor RUNX2 fuels YAP1 signaling and gastric cancer tumorigenesis.

Despite considerable efforts in the detection and treatment of gastric cancer (GC), the underlying mechanism of the progression of GC remains unknown. Our previous work has demonstrated the remarkable role of Runt-related transcription factor 2 (RUNX2), in fueling the invasion and metastasis of GC. The present study aimed to elucidate the role of RUNX2 in tumorigenesis of GC. We assessed Runx2 expression and its clinical significance via bioinformatic analysis of the Cancer Genome Atlas and Gene Expression Omnibus databases. Roles for Runx2 in self-renewal and tumorigenesis were examined in vitro and in vivo. Further bioinformatic analysis was applied to study the mechanism of GC progression. We found that Runx2 was highly expressed in the early stage of GC and positively correlated with a poor clinical outcome of patients. Runx2 was also significantly correlated with clinicopathological features, such as Hp infection, new neoplastic events, primary therapeutic outcome, ethnicity, race, and tumor stage. Multivariate analysis revealed that together with Runx2, age, cancer status, M stage, and T stage were independent prognostic factors for the outcome of GC patients. RUNX2 overexpression induced increased anchorage-independent colony formation, sphere formation, and tumorigenesis in GC cells in vitro and in vivo. Mechanistically, bioinformatic analysis indicated that yes1 associated transcriptional regulator (YAP1) might be a downstream target of RUNX2. Specific knockdown of YAP1 reduced the tumor-initiating ability of GC cells induced by ectopic Runx2 expression. Our findings support the hypothesis that RUNX2 exerts oncogenic properties via YAP1 regulation, highlighting essential roles for RUNX2 and YAP1 in gastric carcinogenesis and suggesting potential therapeutic targets.

Guo Z ，Zhou K ，Wang Q ，Huang Y ，Ji J ，Peng Y ，Zhang X ，Zheng T ，Zhang Z ，Chong D ，Yang Z ... -  《-》

AMOTL1 enhances YAP1 stability and promotes YAP1-driven gastric oncogenesis.

Zhou Y ，Zhang J ，Li H ，Huang T ，Wong CC ，Wu F ，Wu M ，Weng N ，Liu L ，Cheng ASL ，Yu J ，Wong N ，Lo KW ，Tang PMK ，Kang W ，To KF ... -  《-》