Sophoridine Inhibited Epithelial-Mesenchymal Transition, Migration and Invasion in Colorectal Cancer via Regulating ZO-1 and CCND1 Expressions

Abstract

Background: Sophoridine has been reported to suppress multiple cancer types. However, its exact underlying mechanism on the epithelial-mesenchymal transition (EMT) in colorectal cancer (CRC) is yet to be elucidated. Therefore, this study was aimed to reveal its role in colorectal cancer (CRC). Methods: Potential targets of sophoridine and their relevant biological functions were predicted through bioinformatics tools. To investigate the effects of sophoridine on the EMT, migration, and invasion of cells, and the Wnt signaling pathway in CRC, the CRC cells, HCT116 and SW480, were treated with sophoridine and transfected with short hairpin RNA against Zonula occludens-1 (ZO-1) (sh-ZO-1) and Cyclin D1 (CCND1) overexpression plasmid. Furthermore, the quantification analyses, including quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot, were performed to determine the expression levels of EMT-associated factors such as ZO-1, vimentin, snail, alpha-smooth muscle actin (α-SMA), and E-cadherin and proteins associated with the Wnt signaling pathway (CCND1 and β-catenin). Moreover, wound healing and Transwell assays were used to evaluate the migration and invasion within CRC cells. Additionally, xenograft assay was applied to examine tumorigenesis in-vivo. Results: CCND1 and ZO-1 were predicted as the potential targets of sophoridine. Furthermore, sophoridine was observed to reduce the rate of migration and invasion, and decreased the levels of vimentin, snail, α-SMA, CCND1, and β-catenin while elevating the levels of E-cadherin and ZO-1 in CRC cells (p < 0.5). Moreover, ZO-1 knockdown and CCND1 overexpression reversed the inhibitory effects of sophoridine on the cell migration and invasion, as well as on the expressions of vimentin, snail, α-SMA, ZO-1, β-catenin, E-cadherin, and CCND1 (p < 0.5) in CRC cells. Additionally, ZO-1 knockdown and CCND1 overexpression were found to suppress the tumor growth in mice treated with sophoridine (p < 0.01). Conclusion: Sophoridine exhibits inhibitory effects on the EMT, migration, and invasion and reduces tumor growth in CRC by regulating the expression levels of ZO-1 and CCND1.