ASAP1 promotes tumor progression and angiogenesis and independently predicts poor prognosis and lymph node metastasis of gastric cancer

Abstract Background: Although ArfGAP with SH3 Domain, Ankyrin Repeat and PH Domain 1(ASAP1) is involved in the development of various malignancies, its clinical significance and mechanism in gastric cancer (GC) remains unclear.Methods: The effects of ASAP1 on tumor progression, angiogenesis, and epithelial-mesenchymal transition were evaluated in vitro. The effects of ASAP1 on tumor growth and angiogenesis were also explored in vivo. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were used to gather ASAP1 expression data.Results: It showed that ASAP1 expression strongly correlated with the TNM stage (P < 0.0001) and lymph node metastasis (P < 0.0001). Multivariate analyses indicated that ASAP1 overexpression (P < 0.0001) was an independent predictor for overall survival in patients with GC. Moreover, the results revealed that ASAP1 overexpression was independently related to lymph node metastasis (P = 0.0001). ASAP1 knockdown inhibited tumor cell motility, migration, invasion, and angiogenesis, which was accompanied with the downregulation of metastatic and angiogenic biomarkers. Furthermore, ASAP1 inhibition resulted in the simultaneous downregulation of mesenchymal markers and upregulation of epithelial markers. In addition, ASAP1 promoted tumor growth and angiogenesis in the xenograft mice model. The combined datasets (TCGA and GEO) suggested that ASAP1 was associated with malignant behavior of tumor and tumor invasion, metastasis, and angiogenesis.Conclusion: To our knowledge, our study is the first to reveal that ASAP1 promotes tumor progression and angiogenesis, and indicates a prognostic potential in GCs.