The defects in insulin synthesis and the effects of diabetes result in devastating complications, which include nephropathy, retinopathy, stroke, and heart attack . In an attempt to treat Type 1 diabetes mellitus (T1DM) by cellular transplantation, human insulin-producing cells have been derived . Although these cells are promising for potential therapeutic uses, a major problem remains in the generation of expandable cell lines and safety after transplantation. Human pluripotent stem cells (hPSCs) and mesenchymal stem cells (MSCs) have been used as a potential source of insulin-producing cells [3-10]. MSCs are multipotent fibroblast-like cells expressing endoglin (CD105) and 5’-nucleotidase (CD73) [11,12]. However, these phenotypes are also shared by fibroblasts . Fibroblast differentiation to several cell lineages has been described [14,15]. For instance, human dermisderived fibroblasts have been differentiated into insulin-producing cells [16,17]. Additionally, human skin fibroblasts exposed to a DNA methyltransferase inhibitor (5-azacytidine) followed by a specific protocol for pancreas differentiation can give rise to glucose-responsive insulin-producing cells . This fact confirms that insulin-producing cells can be originated from mesoderm-derived cells . Citation: Gupta A, Kurtovic S, Ng TT, Tsuyoshi T, Narwani K, et al. (2015) Mouse Embryonic Fibroblasts Acquire Sarcomagenesis Potential after Differentiating into Insulin-Producing Cells. J Stem Cell Res Ther 5:302.