Polyphyllin II inhibits human bladder cancer migration and invasion by regulating EMT-associated factors and MMPs

The epithelial-mesenchymal transition (EMT) serves vital roles in the angiogenesis, cell invasion and metastasis of various malignant tumors, including bladder cancer. Traditional Chinese medicinal herbs have been demonstrated to exhibit anticancer properties. The present study aimed to screen the sensitivity of bladder cancer to natural compounds by using six classic anti-inflammatory and detoxifying herbs, including the ethanol extract of Paris polyphylla (PPE), Scutellaria barbata, Pulsatillae decoction, Dahuang Huanglian Xiexin decoction, Bazhengsan and Hedyotis diffusa combined with S. barbata, were used to treat bladder cancer cells in vitro. Bladder cancer was more sensitive to PPE compared with the other tested herbs, and PPE significantly suppressed bladder cancer cell migration and invasion. Thus, the present study focused on PPE. Bladder cancer cells were treated with monomer components of PPE, including polyphyllin (PP) I, PPII, PPVI and PPVII. The results demonstrated that PPII treatment significantly inhibited cancer cell migration and invasion, increased the expression level of E-cadherin and decreased the levels of N-cadherin, snail family transcriptional repressor 2, twist family bHLH transcription factor 1, matrix metallopeptidase (MMP) 2 and MMP9 compared with those in the control group (untreated cells). These results suggested that PPII treatment may suppress bladder cancer cell migration and invasion by regulating the expression of EMT-associated genes and MMPs. Therefore, PPE and PPII may have antimetastatic effects and PPII may serve as a potential therapeutic option for inhibiting bladder cancer metastasis.