Immune cell-derived exosomes can increase immunity against tumors. In contrast, tumor-derived exosomes can reduce the immunity and can change the tumor microenvironment to further develop and provide metastasis. These effects take place by an alteration in the innate and adaptive immune cell functions. In this experiment, we studied the natural killer (NK) cells' effectiveness on tumor cells after expansion and thereafter incubated it with exosomes. The exosomes were derived from 2 populations of NK cells: (1) naive NK cells and, (2) NK cells previously exposed to neuroblastoma (NB) cells. Moreover, we have studied the NB-derived exosomes on NK cell function. The molecular load of the characterized exosomes (by means of nanoparticle-tracking analysis, flow cytometry, scanning electron microscopy, and western blot) from NK cells exposed to the NB cell revealed their expression of natural killer cell receptors in addition to CD56, NKG2D, and KIR2DL2 receptors. These exosomes were used to treat NK cells and thereafter administered to NB tumor cells both in vitro and in vivo. Our results showed some kind of NK cells' education by the exosomes. This education from NK cells previously exposed to NB cell-derived exosomes caused efficient and greater cytotoxicity against NB tumors, but NB-derived exosomes act as tumor promoters by providing a tumor supporting niche. Hence, this method of preparing the exosomes has a dramatic effect on activation of anti-NK cells against NB cells.

Breast cancer is the most common cancer in women around the world, and novel prognosis strategies is needed to control more accurate and effective of this malignant disease. Among the latest prognostic markers is E-cadherin, which mediates cell-cell adhesion by associating with catenins. Loss of E-cadherin gene (CDH1) function by genetic or epigenetic alteration leads to tumorigenesis. The aim of our study was to investigate E-cadherin gene promoter methylation in breast cancer, and its correlation with E-cadherin protein expression. Fifty primary breast cancers tissue with ductal type and 50 normal breast sample from the same patients that was located adjacent to tumor region as controls were provided by Imam Reza-based referral and teaching hospital affiliated to Tabriz University of Medical Sciences, Tabriz, Iran. CDH1 promoter region CpG sites methylation and E-cadherin protein expression were determined by bisulfite-specific polymerase chain reaction and Western blot analysis, and the resulting products were sequenced on an ABI automated sequencer for firm conclusion. CDH1 hypermethylation in breast tumor specimen (ductal type) was observed in 94 % (47 of 50) comparing with normal samples methylation, and the significant difference was (p = 0.000). Protein expression in tumor samples tends to diminish with the CDH1 promoter region methylation. In the group of 50 ductal carcinomas cases, most of the cases showing CDH1 hypermethylation correlated inversely with the reduced levels of expression of E-cadherin proteins (95 % of full-methylated tumor samples had no protein expression, and 4.5 % of them had weak expression levels). Possible association was observed between CDH1 methylation and its protein expression (p = 0.000). The results of methylation analysis in promoter region in ten CpG sites (863, 865, 873, 879, 887, 892, 901, 918, 920, and 940) suggested that abnormal CDH1 methylation occurs in high frequencies in ductal breast tumors probably sounds the process of carcinogenesis progression.

The potential of cell therapy is promising in nerve regeneration, but is limited by ethical considerations about the proper and technically safe source of stem cells. We report the successful differentiation of human EnSCs (endometrial stem cells) as a rich source of renewable and safe progenitors into high-efficiency cholinergic neurons. The extracellular signals of NGF (nerve growth factor) and bFGF (basic fibroblast growth factor) could induce cholinergic neuron differentiation. ChAT (choline acetyltransferase), MAP2 (microtubule associated protein 2) and NF-l (neurofilament L) increased after administration of bFGF and NGF to the EnSC cultures. trkC and FGFR2 (fibroblast growth factor receptor 2), which belong to the NGF and bFGF receptors respectively, were determined in populations of EnSCs. NGF, bFGF and their combination differentially influenced human EnSCs high efficiency differentiation. By inducing cholinergic neurons from EnSCs in a chemically defined medium, we could produce human neural cells without resorting to primary culture of neurons. This in vitro method provides an unlimited source of human neural cells and facilitates clinical applications of EnSCs for neurological diseases.

Human EnSCs were successfully differentiated into SMCs, using hydrogels as scaffold. EnSCs may be used for autologous bladder wall regeneration without any immunological complications in women. Currently work is in progress using bioabsorbable nanocomposite materials as EnSC scaffolds for developing urinary bladder wall tissue.

Reconstruction of the bladder wall via in vitro differentiated stem cells on an appropriate scaffold could be used in such conditions as cancer and neurogenic urinary bladder. This study aimed to examine the potential of human endometrial stem cells (EnSCs) to form urinary bladder epithelial cells (urothelium) on nanofibrous silk-collagen scaffolds, for construction of the urinary bladder wall. After passage 4, EnSCs were induced by keratinocyte growth factor (KGF) and epidermal growth factor (EGF) and seeded on electrospun collagen-V, silk and silk-collagen nanofibres. Later we tested urothelium-specific genes and proteins (uroplakin-Ia, uroplakin-Ib, uroplakin-II, uroplakin-III and cytokeratin 20) by immunocytochemistry, RT-PCR and western blot analyses. Scanning electron microscopy (SEM) and histology were used to detect cell-matrix interactions. DMEM/F12 supplemented by KGF and EGF induced EnSCs to express urothelial cell-specific genes and proteins. Either collagen, silk or silk-collagen scaffolds promoted cell proliferation. The nanofibrous silk-collagen scaffolds provided a three-dimensional (3D) structure to maximize cell-matrix penetration and increase differentiation of the EnSCs. Human EnSCs seeded on 3D nanofibrous silk-collagen scaffolds and differentiated to urothelial cells provide a suitable source for potential use in bladder wall reconstruction in women.