The Emerging Role of ADAM 12 Regulates Epithelial-mesenchymal Transition by Activating the Wnt/β-catenin Signaling Pathway in Colorectal Cancer

OBJECTIVE: The objective of this study is to investigate the expression and regulatory mechanisms of A disintegrin and metalloproteinase domain 12 (ADAM12) in colorectal cancer (CRC) tissues and cells. METHODS: Download and analyze the expression levels of ADAM12 in the TCGA and GSE68468 datasets. Collect paraffin-preserved specimens from the Chongqing University Jiangjin Hospital from April 2017 to December 2019 and detect the expression of ADAM12 through immunohistochemistry. Cell experiments were conducted using colorectal cancer cell lines (SW480, HCT116), and cells with high expression of ADAM12 were selected for silencing experiments, and cell proliferation ability using CCK-8, and migration ability of cells in each group using scratch assay and Transwell invasion assay. The EMT markers (E-cadherin, N-cadherin, Vimentin, Twist) and the Wnt/β-catenin markers (β-catenin, GSK-3β, p-GSK-3β, C-MYC, MMP-7) were detected using western blot. We construct a nude mouse CRC tumor model and validate the effect of ADAM12 on EMT and Wnt/β-catenin through immunohistochemistry and Western blot. RESULTS: Bioinformatics showed that increased expression of ADAM12 was strongly correlated with patient prognosis. Immunohistochemistry showed that elevated ADAM12 was associated with vascular invasion (p < 0.05), neurological invasion (p < 0.01), lymph node metastasis (p < 0.01), and TNM staging (p < 0.001). Experiments on cell function revealed that the ADAM12 overexpression group augmented CRC cells' proliferation and migration. After overexpression of ADAM12, the expression of N-cadherin, Vimentin, and Twist increased, while the expression of E-cadherin decreased (p < 0.01). The expression of Proteins related to Wnt/β-catenin: β-catenin, p-GSK-3 β, C-MYC and MMP-7 increased (p < 0.01), and Wnt/β-catenin inhibitor MSAB can counteract the effect of ADAM12 on EMT in CRC cells. The subcutaneous tumor formation experiment results in nude mice showed that ADAM12 promoted tumor growth and induced EMT compared to the control group. CONCLUSION: ADAM12 overexpression through the Wnt/β-catenin signal axis controls the EMT of CRC to promote invasion and metastasis.