Coptisine regulates PI3K/AKT pathway to block bladder cancer progression: a study based on network pharmacology, in vitro and in vivo assays.

BACKGROUND

Coptisine (COP) is a natural compound extracted from Rhizoma Coptidis, and it represses the malignant biological behaviors of bladder cancer cells. However, the underlying molecular mechanism has not been fully elucidated. The aim of this study was to clarify the downstream mechanism by which COP treats bladder cancer.

MATERIALS AND

METHODS

SwissTargetPrediction, STITCH, SymMap, ETCM, TCMSP, CTD databases were used to collect the related targets of COP. GeneCards, DisGeNET, TTD and OMIM databases were used to obtain the related targets of bladder cancer. A Venn diagram was used to identify the potential targets of COP in bladder cancer treatment. The protein-protein interaction network was constructed using STRING database, and Cytoscape 3.9.0 software was used to screen the hub targets. The binding relationship between COP and the hub targets was verified by molecular docking and molecular dynamics simulation. After the bladder cell lines T24 and BIU-87 were treated with different doses of COP, the regulatory effects of COP on PI3K/AKT pathway were investigated with western blotting. Additionally, the tumor-suppressive properties of COP on bladder cancer cells were validated with tumorigenesis model and metastasis model in nude mice.

RESULTS

RAC-alpha serine/threonine-protein kinase 1 (AKT1), glycogen synthase kinase 3 beta (GSK3B), caspase-3 (CASP3), tumor necrosis factor (TNF) and cyclin D1 (CCND1) were identified as the main hub targets of COP in bladder cancer treatment. PI3K/AKT pathway was predicted to be a crucial pathway regulated by COP. The binding affinities between COP and AKT1, GSK3B, CASP3, TNF and CCND1 were high. COP treatment markedly repressed the phosphorylation level of ERK1/2, AKT1, PI3K p85 and mTOR in T24 and BIU-87 cells, and repressed the tumorigenesis and lung/liver metastasis of T24 cells in vivo.

CONCLUSION

COP may be a natural inhibitor for AKT1, GSK3B, CASP3, TNF and CCND1. COP represses PI3K/AKT pathway to suppress the progression of bladder cancer.