Invasion and metastasis are the primary causes of mortality from hepatocellular carcinoma (HCC). Effective inhibition against participants in the tumourigenesis and metastasis process is critical for treatment of HCC. Wnt3a is involved in the development and metastasis of many malignant tumours. However, the specific mechanisms of Wnt3a-mediated cell proliferation, invasion and metastasis in HCC remain unclear. In this study, we found that Wnt3a and its target gene c-Myc showed higher expression in tumour tissues than normal liver tissues in HCC patients; 71.8% of the cases studied had high Wnt3a and c-Myc expression levels (n=32); Wnt3a expression positively correlated with its target genes MMP-7 and c-Myc. Intriguingly, the expression of Wnt3a, MMP-7 and c-Myc is significantly correlated with Notch3 and Hes1 expression. In vitro experiments showed that Wnt3a was highly expressed in MHcc97H and SK-Hep-1 cells. Therefore, Wnt3a expression was silenced with siRNA, and then, MTT, flow cytometry, wound healing and Transwell assays were performed to analyse cell proliferation, cycle, migration and invasion. The results demonstrated that downregulation of Wnt3a expression inhibited cell viability and induced G0/G1 cell cycle arrest via decreased expression of cyclin D1 and c-Myc and increased expression of p21 and p27. In addition, deletion of Wnt3a significantly inhibited migration and invasion by downregulating MMP-2/-7/-9 expression via the MAPK (p38, ERK1/2 and JNK) pathway. In conclusion, our data show that Wnt3a is involved in HCC development. Wnt3a may be an effective target for treatment of HCC.

Background Ovarian cancer (OC) is the second most frequent gynecological cancer and is associated with a poor prognosis because OC progression is often asymptoma-tic and is detected at a late stage. There remains an urgent need for novel targeted therapies to improve clinical outcomes in ovarian cancer. As a nitric oxide prodrug, JS-K is reported highly cytotoxic to human cancer cells such as acute myeloid leukemia, multiple myeloma and breast cancer. This study is aim to investigate the influence of JS-K on proliferation and apoptosis in ovarian cancer cells and explored possible autophagy-related mechanisms, which will contribute to future ovarian cancer therapy and supply theory support that JS-K holds great promise as a novel therapeutic agent against ovarian cancer. Methods The cytotoxicity, extracellular ROS/RNS activity and apoptotic effect of JS-K and indicated inhibitors on ovarian cancer cells in vitro were evaluated by MTT assay, extracellular ROS/RNS assay, caspases activities assay and western blot. Further autophagy effect of JS-K and indicated inhibitors were examined by MTT assay, cell transfection, immunofluorescence analysis, transmission electron microscopy (TEM) analysis and western blot on ovarian cancer cells in vitro. In vivo, the BALB/c-nude female mice with SKOV3 ovarian cancer cells xenograft were used to examine the efficacy of JS-K treatment on tumor growth. PCNA and p62 proteins were analyzed by immunohistochemistry. Results In vitro, JS-K inhibited the proliferation of ovarian cancer cells, induced apoptosis and cell nucleus shrinkage, enhanced the enzymatic activity of caspase-3/7/8/9, and significantly increased the production of ROS/RNS in ovarian cancer A2780 and SKOV3 cells, these effects were attenuated by inhibition of NAC. In addition, JS-K induced autophagy-related proteins and autophagosomes changes in ovarian cancer A2780 and SKOV3 cells. In vivo, JS-K inhibited tumor growth, decreased p62 protein expression and increased the expression levels of PCNA in xenograft models which were established using SKOV3 ovarian cancer cells. Conclusion Taken together, we demonstrated that ROS/RNS stress-mediated apoptosis and autophagy are mechanisms by which SKOV3 cells undergo cell death after treatment with JS-K in vitro. Moreover, JS-K inhibited SKOV3 tumor growth in vivo. An alternative therapeutic approach for triggering cell death in cancer cells could constitute a useful multimodal therapies for treating ovarian cancer, which is known for its resistance to apoptosis-inducing drugs.

JIB-04 is a structurally unique small molecule, known to exhibit anticancer activity and to inhibit the growth of human lung cancer and prostate cancer cell lines. However, the anticancer effect of JIB-04 against human hepatic carcinoma, and its underlying mechanisms, are still unclear. In the present study, MHCC97H and HepG2 cells were employed to investigate the anticancer effects of JIB-04 on cell viability and apoptosis. Annexin V/PI staining, a CCK-8 assay and western blot analysis demonstrated that JIB-04 induced apoptosis in MHCC97H and HepG2 cells, which was evidenced by the expression of proapoptotic and apoptotic proteins including p53, Bak, Bax, caspase-3 and caspase-9. Subsequently, the expression trends of Bcl-2 and p53 were reversed after co-treatment with pifithrin-α (PFT-α, a p53 inhibitor). The results revealed that JIB-04 suppressed the cell viability of MHCC97H and HepG2 cells in a concentration-dependent manner. Meanwhile, it was also demonstrated that JIB-04 effectively triggered MHCC97H and HepG2 cell apoptosis by downregulating Bcl-2/Bax expression, and upregulating proapoptotic and apoptotic protein expression via the p53/Bcl2/caspase signaling pathway. JIB-04 had effects on the inhibition of cell viability and the induction of apoptosis in MHCC97H and HepG2 cells. The underlying mechanism of action of JIB-04 was associated with the p53/Bcl-2/caspase signaling pathway. Our findings provide a foundation for understanding the anticancer effect of JIB-04 on MHCC97H and HepG2 cells, and suggested that JIB-04 may be a promising therapeutic agent in human liver cancer.

BackgroundThis study aimed to investigate the effects of xanthoxyletin, a plant-derived coumarin, on human oral squamous cancer cells in vitro and in mouse xenografts in vivo.Materia/MethodsThe study included SCC-1 human oral cancer cells and EBTr normal embryonic bovine tracheal epithelial cells, which were treated with 0 μM, 5 μM, 10 μM, and 20 μM of xanthoxyletin for 24 hours. The MTT assay assessed cell viability, and autophagy was detected by electron microscopy. Cell apoptosis was investigated using 4′,6-diamidino-2-phenylindole (DAPI), annexin V, and propidium iodide (PI) fluorescence flow cytometry, which was also used to investigate the cell cycle. Protein expression was measured by Western blot. Mouse xenografts were used for the in vivo evaluation of the effects of xanthoxyletin.ResultsXanthoxyletin significantly inhibited the proliferation of oral cancer cells (IC50, 10–30 μM) with lower cytotoxicity for normal cells. Xanthoxyletin treatment was associated with G2/M arrest of the cell cycle and with increased apoptosis and autophagy of SCC-1 cells. Apoptosis and autophagy induced by xanthoxyletin were also associated with changes in expression of the apoptosis-associated proteins, Bax and Bcl-2, and the autophagy-associated proteins, LC3I, LC3II, Beclin 1, p62, and VSp34. Xanthoxyletin inhibited the expression of components of the signaling cascade of the MEK/ERK pathway in the SCC-1 oral cancer cells. The in vivo effects of xanthoxyletin showed inhibition of growth of mouse xenografts.ConclusionsXanthoxyletin inhibited the proliferation of human oral squamous carcinoma cells and induced apoptosis, autophagy, and cell cycle arrest by modulation of the MEK/ERK signaling pathway.

Lung cancer is one of the most common malignancies worldwide, with high mortality and morbidity rates. O2-(2,4-dinitrophenyl)-1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate (JS-K) is a potent anticancer agent that acts against a subset of human non-small cell lung cancer (NSCLC) cell lines; however, the underlying mechanisms of JS-K in NSCLC remain unclear. The present study aimed to evaluate the anticancer effect of JS-K and investigate its underlying mechanisms in A549 and H460 cells. In the present study, A549 and H460 cells were treated with JS-K, and then evaluated by cell viability assay, flow cytometry and western blot analysis. JS-K markedly induced cell cycle arrest at the G 2 /M phase in a concentration and time-dependent manner in both cell lines. This was associated with increased expression levels of p53, and the cell cycle inhibitors p21 WAF1/CIP1 and p27 KIP1 , which, in turn, inhibited the expression of Cdc2, cyclin B1 and cyclin-dependent kinase 2. In addition, JS-K-induced inhibition of proliferation was revealed to be partially modulated by the upregulation of p53 and p21 WAF1 , the ratio of Bax/Bcl-2, and the activation of both the intrinsic and extrinsic apoptotic pathways in A549 and H460 cells. These results demonstrated that JS-K could trigger cell cycle arrest at the G 2 /M phase and apoptosis in A549 and H460 cells, which was likely mediated via the p53/p21 WAF1/CIP1 and p27 KIP1 pathways. Overall, the results indicated that JS-K may be used as an anticancer agent for the treatment of NSCLC.