Imatinib suppresses activation of hepatic stellate cells by targeting STAT3/IL-6 pathway through miR-124.

The activation of hepatic stellate cells is the primary function of facilitating liver fibrosis. Interfering with the coordinators of different signaling pathways in activated hepatic stellate cells (aHSCs) could be a potential approach in ameliorating liver fibrosis. Regarding the illustrated anti-fibrotic effect of imatinib in liver fibrosis, we investigated the imatinib's potential role in inhibiting HSC activation through miR-124 and its interference with the STAT3/hepatic leukemia factor (HLF)/IL-6 circuit. The anti-fibrotic effect of imatinib was investigated in the LX-2 cell line and carbon tetrachloride (CCl4 )-induced Sprague-Dawley rat. The expression of IL-6, STAT3, HLF, miR-124, and α-smooth muscle actin (α-SMA) were quantified by quantitative real-time PCR (qRT-PCR) and the protein level of α-SMA and STAT3 was measured by western blot analysis both in vitro and in vivo. The LX-2 cells were subjected to immunocytochemistry (ICC) for α-SMA expression. After administering imatinib in the liver fibrosis model, histopathological examinations were done, and hepatic function serum markers were checked. Imatinib administration alleviated mentioned liver fibrosis markers. The expression of miR-124 was downregulated, while IL-6/HLF/STAT3 circuit agents were upregulated in vitro and in vivo. Notably, imatinib intervention decreased the expression of IL-6, STAT3, and HLF. Elevated expression of miR-124 suppressed the expression of STAT3 and further inhibited HSCs activation. Our results demonstrated that imatinib not only ameliorated hepatic fibrosis through tyrosine kinase inhibitor (TKI) activity but also interfered with the miR-124 and STAT3/HLF/IL-6 pathway. Considering the important role of miR-124 in regulating liver fibrosis and HSCs activation, imatinib may exert its anti-fibrotic activity through miR-124.

The effect of mesenchymal stem cells and imatinib on macrophage polarization in rat model of liver fibrosis.

Liver fibrosis is a disorder in which inflammatory reactions play an important role, and central to the progression and pathogenesis of this disease are the immune-specific cells known as macrophages. Macrophage types are distinguished from each other by the expression of a series of surface markers. STAT6 and Arg1 play an important role in the polarization of macrophages, so these two factors are downstream of interleukin 4 (IL-4) and IL-13 cytokines and cause to differentiate M2. Therefore, this study aimed to compare the independent effects of imatinib and mesenchymal cell treatment on the polarization of macrophages in rat models of liver fibrosis. The liver fibrosis was induced by the injection of CCL4 for 6 weeks in Sprague-Dawley rats. Then, rats were divided into four different groups, and the effects of imatinib and mesenchymal cells on the expression of Arg1, Ly6c, and STAT6 were evaluated. Histopathology experiments considered the amelioration effect of treatments. Our results showed that Arg1 expression was significantly increased in the groups treated with mesenchymal cells and imatinib compared to the control group. On the other hand, expression of STAT6 was significantly increased in the imatinib-treated mice compared to mesenchymal and control groups. Moreover, the expression of LY6C significantly decreased in imatinib and mesenchymal treated groups compared to the control group. Therefore, our data showed that mesenchymal stem cells and imatinib significantly modulate the fibrotic process in rat models of fibrosis, probably by polarizing macrophages towards an anti-inflammatory profile and increasing the frequency of these cells in liver tissue.

Therapeutic potential of bone marrow-derived mesenchymal stem cells and imatinib in a rat model of liver fibrosis.

Considering the global increase in the prevalence of hepatic fibrosis and ineffective disease treatment, novel therapies are urgently needed. The current study is focused on comparing the therapeutic effects of mesenchymal stem cells (MSC)/imatinib combination therapy to single (MSCs or imatinib) therapy, in a rat model of carbon tetrachloride (CCL4)-induced liver fibrosis. Using rats, hepatic fibrosis was induced by injection of CCL4. Rats were divided into 5 groups: CCL4-induced hepatic fibrosis, phosphate buffered saline (PBS) treatment (vehicle control), Bone marrow-MSCs (BM_MSCs), imatinib, and bone marrow-MSCs/imatinib co-treatment. The therapeutic impact of these approaches was determined using histopathology, sirius-red staining, serum markers, and qRT-PCR for over expression of matrix components. IHC and Western blot were conducted for further confirmation of the results. Single treatment with MSCs or imatinib and the combination therapy, all significantly reduced serum levels of ALT, AST, and ALP concomitant with down-regulation of α-SMA, pro-collagen I, pro-collagen III, collagen IV, and laminin. A significant reduction of ECM components deposits and a decrease in α-SMA expression were detected in all treatment groups. Pathological observations demonstrated that 20% and 40% of the rats in the MSC and MSC/imatinib group were in grade F0 respectively, while 80% of the rats of the imatinib group were in grade 2. Even though all treatment strategies studied resulted in an equally potent reduction in the mRNA and protein expression levels of pro-fibrotic markers, in aspect of pathological observations, our results demonstrate the highest therapeutic potential of utilizing combination of BM-MSCs and imatinib.

Paracrine signals of mesenchymal stem cells induce epithelial to mesenchymal transition in gastric cancer cells.

AIM: Given the high similarity of phenotypical and secretory properties of mesenchymal stem cells and fibroblasts, this study investigated the possibility of inducing EMT process by mesenchymal stem cells. BACKGROUND: Annually, more than 13% of deaths worldwide occur due to cancer. One of the main reasons for the high mortality rate is due to the metastasis of cancer stem cells. Induction of metastasis occurs during the EMT process, which can also be stimulated by fibroblast cells. METHODS: Mesenchymal stem cells (MSCs) were isolated and sub-cultured until passage 3 or 4. AGS cells were co-cultured with MSCs for 4 days. As the positive control group, AGS cells were treated with TGF-ß (10ng/ml) for 48h. Finally, the mRNA expression level of Vimentin, ß-catenin, Snail, and E-cadherin as the EMT pattern, were evaluated by RT-PCR technique. RESULTS: Our findings indicated that AGS cells' crosstalk with MSCs significantly upregulated fibroblast markers including Vimentin and Snail expression. However, no significant changes were identified for ß-catenin gene expression. Additionally, AGS treatment with MSCs resulted in diminished E-cadherin in the targeted cells. CONCLUSION: Based on the results, the AGS cells crosstalk with MSCs activates induction of epithelial mesenchymal transition, which is confirmed through the elevation of Vimentin and Snail expression and reduction of E-cadherin expression as a specific epithelial marker. However, it seems that MSc was not effective on Wnt/ ß-catenin signal gastric cancer cell line.

Evaluation of GKN1 and GKN2 gene expression as a biomarker of gastric cancer.

AIM: The aim of this study was to investigate the expression of GKN1 and GKN2 genes as probable biomarkers for gastric cancer. BACKGROUND: Gastric cancer is a multifactorial process characterized by the uncontrolled growth and dissemination of abnormal cells. Survival rates of gastric cancer tend to be poor, a plausible explanation is a combination of a late-stage diagnosis and limited access to treatment. In this regard, finding relevant and measurable biomarkers is urgently needed. METHODS: 27 samples of gastric cancer tissues were enrolled into this study, according to their pathological responses. The alteration of genes expression were evaluated by Real-Time PCR technique. RESULTS: Our findings showed the significant reduction of Gastrokin-1 and Gastrokine-2 genes expression in the cancerous specimens in comparison with the normal tissues. (P = 0.008 and P = 0.004 respectively). CONCLUSION: Our findings showed the significant reduction of Gastrokin-1 and Gastrokine-2 genes expression in the cancerous specimens in comparison with the normal tissues. (P = 0.008 and P = 0.004 respectively).

Development of experimental fibrotic liver diseases animal model by Carbon Tetracholoride.

AIM: This study is presenting an effective method of inducing liver fibrosis by CCL4 as a toxin in two different breeds of rat models. BACKGROUND: Liver fibrosis is a result of inflammation and liver injury caused by wound healing responses which ultimately lead to liver failure. Consequently, after liver fibrosis, the progression will be continued to liver cirrhosis and at the end stage hepatocellular carcinoma (HCC). Many studies have demonstrated that one of the most important causes of liver fibrosis is Non-alcoholic steatohepatitis (NASH). Fibrotic Liver is affected by an excessive accumulation of extracellular matrix (ECM) proteins like collagen and α-SMA. METHODS: In two different experiments, male Vistar, and Sprague Dawley Rat models ranging from 200±60, corresponding to an age of approximately 10 weeks were utilized in order to induce CCL4 treated liver fibrosis. RESULTS: After 6 weeks of CCL4 injection, different tests have been carried out to verify the liver fibrosis including serum markers such as Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT), molecular tests containing, laminin and α-SMA and also pathological observation by Hematoxylin and eosin staining in both fibrosis and control group. CONCLUSION: The results of Pathology and Real-time PCR showed that fibrosis was induced much more effectively in Sprague Dawley rat model compared with Wistar rats.