In vitro anticancer activities of osthole against renal cell carcinoma cells.

Renal cell carcinoma (RCC) is a common urinary malignancy that is resistant to chemotherapy and radiotherapy. Osthole, a monomer compound extracted from a traditional Chinese herb, has potent anti-tumor effects on various types of cancer cells. However, the therapeutic effects of osthole on RCC remain unclear. In our study, osthole could suppress the proliferation and colony formation of two RCC cell lines, ACHN and 786-O cells, in a dose-dependent manner. Treatment with osthole resulted in a significant, dose-dependent increase in the expression of pro-apoptotic proteins (cleaved caspase-3 and Bax) and decreased expression of anti-apoptotic proteins (Bcl-2 and survivin), which were consistent with evidence of apoptotic nuclear morphology revealed by DAPI staining. Pre-treatment with osthole attenuated the migratory and invasive abilities of RCC cells in a dose-dependent manner, as evidenced by a reduction in migrating cells in a Transwell assay and a decreased wound closure ratio in a scratch assay as compared with the control. Additionally, osthole down-regulated the expression of migration/invasion-related proteins matrix metalloproteinase (MMP)-2 and MMP-9. Osthole significantly up-regulated epithelial biomarkers (E-cadherin and beta-catenin) and down-regulated mesenchymal biomarkers (N-cadherin and vimentin). Furthermore, our results suggest that osthole suppressed the expression of epithelial-mesenchymal transition transcriptional factors Smad-3, Snail-1, and Twist-1. Taken together, the results of this study suggest that osthole might be a potential novel herbal agent against RCC.

Liu L ，Mao J ，Wang Q ，Zhang Z ，Wu G ，Tang Q ，Zhao B ，Li L ，Li Q ... -  《-》

Salinomycin suppresses cancer cell stemness and attenuates TGF-β-induced epithelial-mesenchymal transition of renal cell carcinoma cells.

Metastatic Renal cell carcinoma (RCC) remains a difficult oncologic challenge. Salinomycin is a monocarboxylic polyether antibiotic, which has been proved to possess anti-tumor activities in multiple types of cancer cells. However, its effects on RCC cells remains unclear. In our study, salinomycin could inhibit the proliferation and viability of RCC cell lines 786-O and ACHN. The TUNEL assay revealed that treatment with salinomycin induced DNA breaking in RCC cells. Consistently, Western blotting showed up-regulation of pro-apoptotic biomarkers (cleaved caspase3/9 and cleaved PARP1) and down-regulation of anti-apoptotic biomarker (survivin) in RCC cells after salinomycin treatment, suggesting that salinomycin could induce RCC cell apoptosis. salinomycin treatment also suppressed the sphere formation ability of RCC cells and decreased the expressions of CD105, ALDH1 and CD44, biomarkers for reflecting the stemness of RCC cells. salinomycin treatment effectively down-regulated SMO and Gli1, two key proteins in Hedghog signaling pathway, in a dose-dependent manner. Moreover, salinomycin could suppress the invasion and migration of RCC cells in the presence of TGF-β1, as observed in wound-healing and Transwell assays. salinomycin treatment attenuated TGF-β1-induced epithelial-mesenchymal transition (EMT), as evidenced by its ability to increase E-cadherin expression and decrease N-cadherin, Snail and MMP-2 expressions in RCC cells. Finally, salinomycin inhibited the tumorigenecity of RCC cells in vivo. Our study provides the evidence that salinomycin possess multiple anti-tumor activities against RCC, as it, in particular, suppressed the cancer stem cell properties and attenuated TGF-β-induced EMT. Therefore, it may serve as a potentially therapeutic candidate for metastatic RCC and improve the prognosis of RCC patients.

Liu L ，Wang Q ，Mao J ，Qin T ，Sun Y ，Yang J ，Han Y ，Li L ，Li Q ... -  《-》

Osthole exhibits anti-cancer property in rat glioma cells through inhibiting PI3K/Akt and MAPK signaling pathways.

The purpose of this study was to investigate how Osthole affects glioma cell proliferation, apoptosis, invasion and migration. Rat glioma cells were treated with different concentrations of Osthole (0 µM, 25 µM, 50 µM, and 100 µM). Cell proliferation was assessed by measuring PCNA expression and CCK8 assay at different time points. Apoptosis was evaluated by measuring the expression of pro-apoptotic protein including Bax, Bcl2, PARP, and cleaved Caspase3, and of anti-apoptotic protein Survivin. Cell migration and invasion were assessed using different methods. Signaling pathways such as PI3K/Akt and MAPK, which are involved in the development of glioma cells, were also investigated in this study. Treatment with Osthole markedly inhibits glioma cell proliferation, as assessed by western blot with the PCNA antibody. Osthole also induces cell apoptosis by upregulating the expression of pro-apoptotic proteins, and by reducing the expression of anti-apoptotic factors. Moreover, C6 cell migration and invasion were efficiently inhibited in groups treated with Osthole, compared to the control group. Additionally, inhibition of PI3K/Akt and MAPK signaling pathway was also observed in C6 cells treated with Osthole. Our findings showed an anti-cancer effect of Osthole on glioma cells, including the proliferation inhibition, apoptosis induction, and migration/invasion inhibition. Further investigation in C6 glioma cells implicated the role of Osthole in essential pathways controlling glioma cell progression. Taken together, our data suggested that Osthole may have a potential application in glioma therapy.

Ding D ，Wei S ，Song Y ，Li L ，Du G ，Zhan H ，Cao Y ... -  《-》

Anti-tumor effects of osthole on ovarian cancer cells in vitro.

Cnidium monnieri (L.) Cusson is a commonly used traditional Chinese medicine to treat gynecological disease in some countries. Osthole, an active O-methylated coumadin isolated from Cnidium monnieri (L.) Cusson, has been shown to induce various beneficial biochemical effects such as anti-seizure and anti-inflammatory effects. However, the anti-tumor mechanism of osthole is not well known. Here, we show that osthole inhibited the proliferation and migration of two widely used ovarian cancer cell lines, A2780 and OV2008 cells, in a dose-dependent manner. The study investigated the molecular mechanisms underlying ovarian cancer cells proliferation, apoptosis, cell cycle arrest and migration triggered by osthole. Ovarian cancer cell lines A2780, OV2008 and normal ovarian cell line IOSE80 were used as experimental model. MTT assay was employed to evaluate cell viability. Flow cytometry assays were performed to confirm apoptosis and cell cycle. We employed wound healing and transwell assays to delineate invasive and migratory potential triggered by osthole. MTT assays indicated that cell viability significantly decreased in ovarian cancer cells treated with osthole without effect on normal ovarian cells. Flow cytometric analysis revealed that osthole suppressed cells proliferation by promoting G2/M arrest and inducing apoptosis. The underlying mechanisms involved were regulation of the relative apoptotic protein Bcl-2, Bax and Caspase 3/9. In addition, wound healing and transwell assays revealed that the migratory potential and activity of matrix metalloproteinase MMP-2 and MMP-9 were markedly inhibited when cells were exposed to osthole. Our findings suggested that osthole has the potential to be used in novel anti-cancer therapeutic formulations for ovarian cancer treatment.

Jiang G ，Liu J ，Ren B ，Tang Y ，Owusu L ，Li M ，Zhang J ，Liu L ，Li W ... -  《-》

Calcitriol inhibits migration and invasion of renal cell carcinoma cells by suppressing Smad2/3-, STAT3- and β-catenin-mediated epithelial-mesenchymal transition.

Low vitamin D status is associated with progression in patients with renal cell carcinoma (RCC). The present study found that vimentin, a mesenchymal marker, was accordingly upregulated, and E-cadherin, an epithelial marker, was downregulated in RCC patients with low vitamin D status. Thus, we investigated the effects of calcitriol or vitamin D3, an active form of vitamin D, on epithelial-mesenchymal transition (EMT) in RCC cells. RCC cells were treated by two models. In model 1, three RCC cell lines, ACHN, 786-O and CAKI-2, were incubated with either LPS (2.0 μg/mL) or transforming growth factor (TGF)-β1 (10 ng/mL) in the presence or absence of calcitriol (200 nmol/L). In model 2, two RCC cell lines, ACHN and CAKI-2, were incubated with calcitriol (200 nmol/L) only. Calcitriol inhibited migration and invasion not only in TGF-β1-stimulated but also in TGF-β1-unstimulated RCC cells. Moreover, calcitriol suppressed E-cadherin downregulation and vimentin upregulation not only in TGF-β1-stimulated but also in TGF-β1-unstimulated ACHN and CAKI-2 cells. Calcitriol attenuated LPS-induced upregulation of MMP-2, MMP-7, MMP-9, MMP-26 and urokinase-type plasminogen activator (u-PA) in ACHN cells. In addition, calcitriol blocked TGF-β1-induced nuclear translocation of ZEB1, Snail and Twist1 in ACHN and CAKI-2 cells. Mechanistically, calcitriol suppressed EMT through different signaling pathways: (i) calcitriol suppressed Smad2/3 phosphorylation by reinforcing physical interaction between vitamin D receptor (VDR) and Smad3 in TGF-β1-stimulated RCC cells; (ii) calcitriol inhibited signal transducer and activator of transcription (STAT)3 activation in LPS-stimulated RCC cells; (iii) calcitriol inhibited β-catenin/TCF-4 activation by promoting integration of VDR with β-catenin in TGF-β1-unstimulated RCC cells. Taken together, calcitriol inhibits migration and invasion of RCC cells partially by suppressing Smad2/3-, STAT3- and β-catenin-mediated EMT.

Xu S ，Zhang ZH ，Fu L ，Song J ，Xie DD ，Yu DX ，Xu DX ，Sun GP ... -  《-》