PurposeIn this study, we investigated the molecular mechanism involved in ethanol (EtOH)-mediated proliferation of breast cancer cells.MethodsEtOH concentration was optimized by studying its effect on cell proliferation in MCF-7 and MDA MB-231 cells. We used flow cytometry and immunoblot analysis to evaluate the increased proliferation caused by the optimized concentrations of EtOH. The mechanism of EtOH-mediated proliferation was determined using reactive oxygen species (ROS) release assay, reverse transcription polymerase chain reaction, and immunoblot studies. Gene silencing followed by quantitative real-time polymerase chain reaction studies and inhibitor studies indicated the involvement of signal transducer and activator of transcription 3 (STAT3) in EtOH-mediated breast cancer proliferation.ResultsExposure to EtOH caused an increase in cell proliferation and an accumulation of cells in S-phase in MCF-7 (347 µM EtOH) and MDA MB-231 (173 µM EtOH) cells. Additionally, increased release of ROS and the expression of pro-inflammatory cytokines, such as interleukin 6 and tumor necrosis factor α, confirmed that the proliferation was induced by the ROS-linked inflammatory response in breast cancer. The proinflammatory response was followed by phosphorylation of STAT3. The importance of STAT3 activation in EtOH-mediated proliferation was confirmed through the silencing of STAT3, followed by an investigation on the expression of cyclins and matrix metalloproteinases. Finally, studies using specific inhibitors indicated that the EtOH-mediated effect on STAT3 activation could be regulated by phosphoinositide-3-kinase and Janus kinase 2.ConclusionThe study demonstrates the involvement of STAT3 signaling in EtOH-mediated breast cancer proliferation.

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Cell derived matrices (CDMs) are scaffolds constructed by decellularization of cellular matrices from different tissues and organs. Since cell derived matrices mimic the ECM of native tissues, CDM plays an essential role in the preparation of bioscaffolds. CDM scaffolds from Mesenchymal Stem Cells (MSCs) have been reported to support cell adhesion and proliferation of its own cells. Therefore, in this study we aimed to test if growth of human Wharton’s jelly derived MSCs (hWJ-MSCs) may be enhanced when cultured on their own cell derived matrices. To do this, MSCs were induced to generate ECM using ascorbic acid. Thus, obtained matrices were decellularized and characterized quantitatively for changes in their biochemical components (total protein, collagen, glycosaminoglycans) and qualitatively for fibronectin, laminin and collagen (I & IV) by immunostaining. Our results show the retention of essential ECM components in the decellularized WJ-CDM. The influence of WJ-MSC-derived CDM on proliferation and differentiation of WJ-MSCs were evaluated by comparing their growth on collagen and fibronectin only coated plates. A non-coated tissue culture polystyrene plate (TCPS/WC) served as control. Our cell proliferation results show that no significant changes were observed in the proliferation of MSCs when cultured on WJ-MSC derived CDM as compared to the bio-coated and non-coated cultures. However, gene expression analysis of the differentiation process showed that osteogenic and adipogenic differentiation potential of the WJ-MSCs was significantly increased upon culturing them on WJ-MSC-CDM. In conclusion, the present study reveals that the WJ-MSCs cultured on WJ-MSC-CDM may augment osteogenic and adipogenic differentiation.