Molecular and Celluar Mechanism Studies on Anticancer Effects of Chinese Medicines

link_to_OA_fulltex

Computational Identification and Modeling of Crosstalk between Phosphorylation, O-β-glycosylation and Methylation of FoxO3 and Implications for Cancer Therapeutics

FoxO3 is a member of the forkhead class of transcription factors and plays a major role in the regulation of diverse cellular processes, including cell cycle arrest, DNA repair, and protection from stress stimuli by detoxification of reactive oxygen species. In addition, FoxO3 is a tumor suppressor and has been considered as a novel target for cancer therapeutics. Phosphorylation of FoxO3 via the AKT, IKK, and ERK pathways leads to deregulation, cytoplasmic retention, degradation of FoxO3 and favors tumor progression. Identification of the amino acid residues that are the target of different posttranslational modifications (PTMs) provides a foundation for understanding the molecular mechanisms of FoxO3 modifications and associated outcomes. In addition to phosphorylation, serine and threonine residues of several proteins are regulated by a unique type of PTM known as O-β-glycosylation, which serves as a functional switch. We sought to investigate the crosstalk of different PTMs on the FoxO3 which leads to the onset/progression of various cancers and that could also potentially be targeted as a therapeutic point of intervention. A computational workflow and set of selection parameters have been defined for the identification of target sites and crosstalk between different PTMs. We identified phosphorylation, O-β-GlcNAc modification, and Yin Yang sites on Ser/Thr residues, and propose a potential novel mechanism of crosstalk between these PTMs. Furthermore, methylation potential of human FoxO3 at arginine and lysine residues and crosstalk between methylation and phosphorylation have also been described. Our findings may facilitate the study of therapeutic strategies targeting posttranslational events

A chinese medicine formula Gegen Qinlian decoction suppresses expansion of human renal carcinoma with inhibition of matrix metalloproteinase-2

© The Author(s) 2014. Aim of Study. Gegen Qinlian decoction (GQLD) is an ancient Chinese medicine formula for treating diseases with inner heat. The aim of this study is to investigate the antitumor effect of GQLD in human renal carcinoma cell (RCC) and its possible mechanism. Method. High-performance liquid chromatography was used to identify and quantify active compounds in GQLD. Inhibition of tumor growth was determined by xenograft model. Cell viability on treatment with the decoction was determined by MTT assay; quantitative real-time polymerase chain reaction and immunoblotting were used to determine gene and protein expression; matrix metalloproteinase-2 (MMP-2) activity was detected by gelatin zymography and in vitro enzymatic reaction assay. Results. Thirteen major peaks were detected in the decoction, 8 of which were identified as berberine, baicalin and baicalein, pueranin, daizidin, liquiritin, wogonoside, and wogonin. GQLD exhibited potent inhibition on xenografted expansion of RCC cells. Interestingly, GQLD treatment did not induce cell death to RCC cells, but blocked the neoangiogenesis in xenografted RCC tumor. Particularly, we found that GQLD significantly inhibited MMP-2 in RCC cells, which was involved as a critical factor in avascular growth of RCC. GQLD directly suppressed the enzyme activity of MMP-2. Radix Scutellariae was the major herbal component that contributed to the potent inhibition of MMP-2. Conclusion. The findings of this study provide experimental evidence of the inhibition of expansion and neoangiogenesis of renal carcinoma by Chinese medicine formula GQLD with involvement of MMP-2 suppression.Link_to_subscribed_fulltex

New Natural Pigment Fraction Isolated from Saw Palmetto: Potential for Adjuvant Therapy of Hepatocellular Carcinoma

For the first time, we discovered a small proportion of aqueous fraction from Saw Palmetto apart from the fatty acid-rich fraction exhibited pharmacological activity. Therefore, this study aims to explore the anti-tumor potential of red pigmented aqueous fraction of Saw Palmetto, NYG on human hepatocellular carcinoma and its possible targets. Subcutaneous xenograft and orthotopic implantation models of HCC were used to evaluate the tumor inhibitory effect of NYG. Human hepatocellular carcinoma (HCC) cell lines and human umbilical vein endothelial cells (HUVEC) were used as in vitro model. The mRNA expression was conducted by qPCR. Protein expression was monitored by immunoblotting and immunohistochemistry. Cell migration and blood vessel formation were determined by chamber assay and tube formation assay, respectively. Significant tumor inhibition of NYG in dose-dependent manner was observed on subcutaneous xenograft and orthotopic HCC model. NYG has no direct action on cell viability or VEGF secretion of HCC cells. However, NYG reduced in vitro migration and vessel formation activities of HUVEC cells, as well as in vivo intratumoral neovascularization. NYG attenuated extracellular signal-regulated kinases (ERK) activation in endothelial cells, which may be associated with the suppression of migration and tube formation of HUVEC. NYG suppressed tumor expansion of HCC via inhibiting neovascularization, and may be potential adjuvant treatment for HCC