A simple and solution-phase method for functionalization of selenium nanoparticles (SeNPs) with Spirulina polysaccharides (SPS) has been developed in the present study. The cellular uptake and anticancer activity of SPS-SeNPs were also evaluated. Monodisperse and homogeneous spherical SPS-SeNPs with diameters ranging from 20 nm to 50 nm were achieved under optimized conditions, which were stable in the solution phase for at least 3 months. SPS surface decoration significantly enhanced the cellular uptake and cytotoxicity of SeNPs toward several human cancer cell lines. A375 human melanoma cells were found extremely susceptible to SPS-SeNPs with half maximal (50%) inhibitory concentration value of 7.94 µM. Investigation of the underlying mechanisms revealed that SPS-SeNPs inhibited cancer cell growth through induction of apoptosis, as evidenced by an increase in sub-G1 cell population, deoxyribonucleic acid fragmentation, chromatin condensation, and phosphatidylserine translocation. Results suggest that the strategy to use SPS as a surface decorator could be an effective way to enhance the cellular uptake and anticancer efficacy of nanomaterials. SPS-SeNPs may be a potential candidate for further evaluation as a chemopreventive and chemotherapeutic agent against human cancers.
26 January 2016 in International Journal of Oncology
Aberrant Wnt signaling pathway is associated with a wide array of tumor types and plays an important role in the drug resistance of cancer stem cells (CSCs). To explore the effects and mechanism of WNT signaling pathway inhibitor XAV939 on drug resistance in colon cancer cells, the colon cancer cells SW480 and SW620 were treated with 5-fluorouracil (5-FU)/cisplatin (DDP) alone or combined with XAV939. Cell cycle distribution, apoptosis level and the percentage of CD133+ cells were detected by flow cytometry. The protein expression of Axin, β-catenin, EpCAM, TERT and DCAMKL-1 was detected by western blotting. XAV939 upregulated Axin , decreased the total and nuclei of β-catenin in SW480 and SW620 cells. Furthermore, XAV939 significantly downregulated the CSC markers EpCAM, TERT and DCAMKL-1 in SW480 cells, as well as EpCAM in SW620 cells. No significant difference was found in the apoptosis of SW480 and SW620 cells with XAV939 treatment, but XAV939 significantly increased apoptosis induced by 5-FU/DDP in SW480 cells, whereas, the effects were slight in SW620 cells. Collectively, we show for the first time that the WNT signaling pathway inhibitor XAV939 was able to significantly increase the apoptosis induced by 5-FU/DDP, accompanied by the protein expression level alternation of β-catenin, Axin and CSC markers in colon cancer cells. Axin, an important component of Wnt/β-catenin signaling pathway could be a potential molecular target for reversing multidrug resistance in colon cancer.
The diverse structural and functional heterogeneity of γδ T cells is related to their distinct role in cancer immunity. The different phenotypes of γδ T cells in patients with acute myeloid leukemi...
1 January 2003 in World Journal of Gastroenterology
Glioma, the most common human primary brain tumor, is characterized by invasive capabilities and angiogenesis. Vasorin (VASN), a transmembrane protein, is reported to be associated with vascular injury repair and overexpressed in some human tumors. However, its role in tumor progression and angiogenesis in glioma is unknown. In this study, VASN was shown to be overexpressed in high‐grade gliomas, and the expression level correlated with tumor grade and microvessel density in glioma specimens. Glioma patients with high VASN expression had a shorter overall survival time. Knockdown of VASN in glioma cells by shRNA significantly inhibited the malignancy of glioma, including cell proliferation, colony formation, invasion, and sphere formation. Ectopic expression of VASN increased glioma progression in vitro. The expression of VASN correlated with the mesenchymal type of glioblastoma multiforme (GBM) subtyped by gene set enrichment analysis (GSEA). Our results showed that the concentration of VASN was increased in the conditioned medium (CM) from glioma cells with VASN overexpression, and the CM from glioma cells with knockdown or overexpressed of VASN inhibited or promoted HUVEC migration and tubulogenesis in vitro, respectively. Glioma growth and angiogenesis were stimulated upon ectopic expression of VASN in vivo. In mechanism, the STAT3 and NOTCH pathways were found to be activated and inhibited by VASN overexpression, respectively. Our findings suggest that VASN stimulates tumor progression and angiogenesis in glioma, and as such, represents a novel therapeutic target for glioma.