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Myocardial fibrosis (MF) can cause heart remodeling and it is an independent risk factor for malignant arrhythmias, sudden cardiac death, and other malignant cardiovascular events. It is often characterized by myocardial interstitial collagen deposition and hyperproliferation of cardiac fibroblasts (CFs). The transforming growth factor-β1 (TGF-β1) is the most influential profibrogenic factor. Resveratrol (RSV) is an active polyphenol substance that inhibits myocardial fibrosis. The mechanism of RSV-mediated inhibition of the proliferation of CFs at the microRNA level is not fully understood. We used TGF-β1 to induce CFs proliferation to simulate the pathogenesis of myocardial fibrosis. Neonatal rat CFs were treated with TGF-β1 in the presence or absence of resveratrol. Cell proliferation was measured using the CCK-8 and EdU assay. Collagen secretion was measured using hydroxyproline kit. Further, qPCR analysis was performed to determine microRNA levels after TGF-β1 or resveratrol treatment. To identify the target gene for miR-17, miR-17 was overexpressed or silenced, and the mRNA and protein levels of Smad7 were assessed. The effects of miR-17 silencing or Smad7 overexpression on cell proliferation and collagen secretion were also examined. Resveratrol treatment significantly decreased the TGF-β1-induced CF proliferation and collagen secretion. Resveratrol also decreased the levels of miR-17, miR-34a, and miR-181a in TGF-β1-treated CFs. Overexpression of miR-17 decreased the Smad7 mRNA and protein levels while silencing miR-17 increased them. Additionally, silencing miR-17 or overexpressing Smad7 decreased the TGF-β1-induced CFs proliferation and collagen secretion. In conclusion, resveratrol inhibits TGF-β1-induced CFs proliferation and collagen secretion. This inhibitory effect of resveratrol is orchestrated by the downregulation of miR-17 and the regulation of Smad7. [ABSTRACT FROM AUTHOR]

Uncontrolled excessive activation of Hedgehog (Hh) signaling pathway is linked to a number of human malignant tumorigenesis. To obtain valuable Hh pathway inhibitors from natural product, in present study, a pair of novel epimers, Cynanbungeigenin C (CBC) and D (CBD) from the plant Cynanchum bungei Decne were chemically characterized by multiple spectroscopic data and chemical derivatization, and evaluated for their inhibition on Hh pathway. Mechanistically, CBC and CBD block Hh pathway signaling not through targeting Smo and Sufu, but at the level of Gli. In addition, both eipmers significantly suppress Hh pathway-dependent Ptch+/-; p53-/- medulloblastoma in vitro and in vivo. Furthermore, both CBC and CBD inhibited two Smo mutants induced Hh pathway activation, which suggested that they are potential compounds for the treatment of medulloblastoma with primary or acquired resistance to current Smo inhibitors. These results highlight the potential of CBC and CBD as effective lead compounds in the treatment of medulloblastoma and other Hh-dependent malignancy. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigated the expression and function of thymosinα1 (Thyα1) in human pancreatic cancer. We found that human pancreatic cancer cell lines Panc-1, Panc03.27, ASPC-1, and PL45 cells significantly over-expressed the mRNA of Thyα1 as compared to the normal human pancreatic ductal epithelium (HPDE) cells.. Thyα1 mRNA and protein levels were also over-expressed in clinical pancreatic adenocarcinoma specimens. In addition, synthetic Thyα1 significantly promoted Panc-1 cell proliferation and increased phosphorylation of ERK1/2 and JNK. Furthermore, Thyα1 increased the secretion of multiple cytokines including IL-10, IL-13, and IL-17 in Panc-1 cells. Thus, Thyα1 may have a new role in pancreatic cancer pathogenesis. [Copyright &y& Elsevier]