Physcion 8-O-β-glucopyranoside inhibits testicular germ cell tumors through regulating microRNA-199a

Testicular germ cell tumors (TGCTs) are frequently diagnosed solid tumors in young adult males. The present study aimed to investigate the anti-tumor function of Physcion 8-O-β-Glucopyranoside (PG) in TGCTs, and to explore the underlying anti-tumor mechanism of PG in TGCTs. Cell viability was measured by a cell counting kit-8 (CCK-8) assay, and the cell cycle distribution was analyzed by flow cytometry. Cell apoptosis was measured using TUNEL staining and flow cytometry. The lactate dehydrogenase (LDH) release, glucose consumption, lactate production, and ATP generation were determined using a Flex Bioanalyzer. The expression of miR-199a was measured by qRT-PCR, and the expression of marker proteins were analyzed by western blotting. Moreover, a xenograft mouse model was used for investigating PG's antitumor effect in vivo. The results showed that PG significantly inhibited NTERA2 and NCCIT cell proliferation, blocked the cell cycle, and induced cell apoptosis. Furthermore, PG suppressed LDH release, glucose consumption, lactate production, and ATP generation in NTERA2 and NCCIT cells. The results of investigating the molecular mechanism of PG in TGCTs showed that miR-199a was decreased in TGCTs but was increased by PG in a dose-dependent manner. MiR-199a knockdown significantly increased NTERA2 and NCCIT cell proliferation, decreased the apoptotic cell rates, and promoted LDH release, glucose consumption, lactate production, and ATP generation. The effects of PG on TGCTs were reversed by miR-199a silencing. In addition, we found that PG significantly inhibited tumor growth in vivo. In conclusion, our study revealed that PG modulated cell proliferation, the cell cycle, apoptosis, and glucose metabolism in TGCTs through regulating miR-199a. These findings indicate a novel therapeutic strategy and a potential biomarker for TGCT treatment.

Physcion 8-O-β-glucopyranoside prevents hypoxia-induced epithelial-mesenchymal transition in colorectal cancer HCT116 cells by modulating EMMPRIN

Epithelial-mesenchymal transition (EMT) is considered as the most important mechanism that underlies the initiation of cancer metastasis. Here we report that Physicon 8-O-β-glucopyranoside (PG), a major active ingredient from a traditional Chinese herbal medicine Rumex japonicus Houtt, is capable of preventing human colorectal cancer cells from hypoxia-induced EMT. The treatment of the cells with PG reversed the EMT-related phenotype that has the morphological changes, down-regulation of E-cadherin, and hypoxia-induced cell migration and invasion. The effect was mediated at least in part by inhibiting the mRNA and protein expressions of EMMPRIN via modulation of PTEN/Akt/HIF-1α pathway. In addition, we found that PG-mediated prevention of EMT involved blockade of the hypoxia-induced up-regulation of Snail, Slug and Twist. In summary, this study showed that PG can prevent EMT induced by hypoxia, the environment that commonly exists in the center of a solid tumor. Given the low toxicity of PG to the healthy tissues, our study suggests that PG can serve as a safe therapeutic agent for suppressing cancer metastasis.