Diabetic microenvironment deteriorates the regenerative capacities of adipose mesenchymal stromal cells.

BACKGROUND: Type 2 diabetes is an endocrine disorder characterized by compromised insulin sensitivity that eventually leads to overt disease. Adipose stem cells (ASCs) showed promising potency in improving type 2 diabetes and its complications through their immunomodulatory and differentiation capabilities. However, the hyperglycaemia of the diabetic microenvironment may exert a detrimental effect on the functionality of ASCs. Herein, we investigate ASC homeostasis and regenerative potential in the diabetic milieu. METHODS: We conducted data collection and functional enrichment analysis to investigate the differential gene expression profile of MSCs in the diabetic microenvironment. Next, ASCs were cultured in a medium containing diabetic serum (DS) or normal non-diabetic serum (NS) for six days and one-month periods. Proteomic analysis was carried out, and ASCs were then evaluated for apoptosis, changes in the expression of surface markers and DNA repair genes, intracellular oxidative stress, and differentiation capacity. The crosstalk between the ASCs and the diabetic microenvironment was determined by the expression of pro and anti-inflammatory cytokines and cytokine receptors. RESULTS: The enrichment of MSCs differentially expressed genes in diabetes points to an alteration in oxidative stress regulating pathways in MSCs. Next, proteomic analysis of ASCs in DS revealed differentially expressed proteins that are related to enhanced cellular apoptosis, DNA damage and oxidative stress, altered immunomodulatory and differentiation potential. Our experiments confirmed these data and showed that ASCs cultured in DS suffered apoptosis, intracellular oxidative stress, and defective DNA repair. Under diabetic conditions, ASCs also showed compromised osteogenic, adipogenic, and angiogenic differentiation capacities. Both pro- and anti-inflammatory cytokine expression were significantly altered by culture of ASCs in DS denoting defective immunomodulatory potential. Interestingly, ASCs showed induction of antioxidative stress genes and proteins such as SIRT1, TERF1, Clusterin and PKM2. CONCLUSION: We propose that this deterioration in the regenerative function of ASCs is partially mediated by the induced oxidative stress and the diabetic inflammatory milieu. The induction of antioxidative stress factors in ASCs may indicate an adaptation mechanism to the increased oxidative stress in the diabetic microenvironment.

Plasma-derived extracellular matrix for xenofree and cost-effective organoid modeling for hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) causes significant cancer mortality worldwide. Cancer organoids can serve as useful disease models by high costs, complexity, and contamination risks from animal-derived products and extracellular matrix (ECM) that limit its applications. On the other hand, synthetic ECM alternatives also have limitations in mimicking native biocomplexity. This study explores the development of a physiologically relevant HCC organoid model using plasma-derived extracellular matrix as a scaffold and nutritive biomatrix with different cellularity components to better mimic the heterogenous HCC microenvironment. Plasma-rich platelet is recognized for its elevated levels of growth factors, which can promote cell proliferation. By employing it as a biomatrix for organoid culture there is a potential to enhance the quality and functionality of organoid models for diverse applications in biomedical research and regenerative medicine and to better replicate the heterogeneous microenvironment of HCC. METHOD: To generate the liver cancer organoids, HUH-7 hepatoma cells were cultured alone (homogenous model) or with human bone marrow-derived mesenchymal stromal cells and human umbilical vein endothelial cells (heterogeneous model) in plasma-rich platelet extracellular matrix (ECM). The organoids were grown for 14 days and analyzed for cancer properties including cell viability, invasion, stemness, and drug resistance. RESULTS: HCC organoids were developed comprising HUH-7 hepatoma cells with or without human mesenchymal stromal and endothelial cells in plasma ECM scaffolds. Both homogeneous (HUH-7 only) and heterogeneous (mixed cellularity) organoids displayed viability, cancer hallmarks, and chemoresistance. The heterogeneous organoids showed enhanced invasion potential, cancer stem cell populations, and late-stage HCC genetic signatures versus homogeneous counterparts. CONCLUSION: The engineered HCC organoids system offers a clinically relevant and cost-effective model to study liver cancer pathogenesis, stromal interactions, and drug resistance. The plasma ECM-based culture technique could enable standardized and reproducible HCC modeling. It could also provide a promising option for organoid culture and scaling up.

Current status of stem cell therapy for type 1 diabetes: a critique and a prospective consideration.

Over the past decade, there had been progress in the development of cell therapy for insulin-dependent diabetes. Nevertheless, important hurdles that need to be overcome still remain. Protocols for the differentiation of pluripotent stem cells into pancreatic progenitors or fully differentiated ß-cells have been developed. The resulting insulin-producing cells can control chemically induced diabetes in rodents and were the subject of several clinical trials. However, these cells are immunogenic and possibly teratogenic for their transplantation, and an immunoisolation device and/or immunosuppression is needed. A growing number of studies have utilized genetic manipulations to produce immune evasive cells. Evidence must be provided that in addition to the expected benefit, gene manipulations should not lead to any unforeseen complications. Mesenchymal stem/stromal cells (MSCs) can provide a viable alternative. MSCs are widely available from many tissues. They can form insulin-producing cells by directed differentiation. Experimentally, evidence has shown that the transplantation of allogenic insulin-producing cells derived from MSCs is associated with a muted allogeneic response that does not interfere with their functionality. This can be explained by the immunomodulatory functions of the MSC subpopulation that did not differentiate into insulin-producing cells. Recently, exosomes derived from naive MSCs have been used in the experimental domain to treat diabetes in rodents with varying degrees of success. Several mechanisms for their beneficial functions were proposed including a reduction in insulin resistance, the promotion of autophagy, and an increase in the T regulatory population. However, euglycemia was not achieved in any of these experiments. We suggest that exosomes derived from ß-cells or insulin-producing cells (educated) can provide a better therapeutic effect than those derived from undifferentiated cells.

Transplantation of insulin-producing cells derived from human mesenchymal stromal/stem cells into diabetic humanized mice.

BACKGROUND: The purpose of this study was to investigate allogenic immune responses following the transplantation of insulin-producing cells (IPCs) differentiated from human adipose tissue-derived stem cells (hAT-MSCs) into humanized mice. METHODS: hAT-MSCs were isolated from liposuction aspirates obtained from HLA-A2-negative healthy donors. These cells were expanded and differentiated into IPCs. HLA-A2-positive humanized mice (NOG-EXL) were divided into 4 groups: diabetic mice transplanted with IPCs, diabetic but nontransplanted mice, nondiabetic mice transplanted with IPCs and normal untreated mice. Three million differentiated cells were transplanted under the renal capsule. Animals were followed-up to determine their weight, glucose levels (2-h postprandial), and human and mouse insulin levels. The mice were euthanized 6-8 weeks posttransplant. The kidneys were explanted for immunohistochemical studies. Blood, spleen and bone marrow samples were obtained to determine the proportion of immune cell subsets (CD4+, CD8+, CD16+, CD19+ and CD69+), and the expression levels of HLA-ABC and HLA-DR. RESULTS: Following STZ induction, blood glucose levels increased sharply and were then normalized within 2 weeks after cell transplantation. In these animals, human insulin levels were measurable while mouse insulin levels were negligible throughout the observation period. Immunostaining of cell-bearing kidneys revealed sparse CD45+ cells. Immunolabeling and flow cytometry of blood, bone marrow and splenic samples obtained from the 3 groups of animals did not reveal a significant difference in the proportions of immune cell subsets or in the expression levels of HLA-ABC and HLA-DR. CONCLUSION: Transplantation of IPCs derived from allogenic hAT-MSCs into humanized mice was followed by a muted allogenic immune response that did not interfere with the functionality of the engrafted cells. Our findings suggest that such allogenic cells could offer an opportunity for cell therapy for insulin-dependent diabetes without immunosuppression, encapsulation or gene manipulations.

Hepatocellular carcinoma cell line-microenvironment induced cancer-associated phenotype, genotype and functionality in mesenchymal stem cells.

Mesenchymal stromal cells (MSCs) have shown promise in liver cancer treatment. However, when MSCs are recruited to hepatic site of injury, they acquire cancerous promoting phenotype. AIMS: To assess the influence of Hepatocellular carcinoma (HCC) microenvironment on human adipose MSCs (hA-MSCs) and predict hA-MSCs intracellular miRNAs role. MATERIALS AND METHODS: After indirect co-culturing with Huh-7 cells, hA-MSCs were characterized via cell cycle profile, proliferation and migration potentials by MTT and scratch assays respectively. Functional enrichment analysis of deregulated proteins and miRNA targets was also analyzed. KEY FINDINGS: Co-cultured hA-MSCs could acquire a cancer-associated phenotype as shown by upregulation of CAF, cancer markers, and downregulation of differentiation markers. Migration of these cancer-associated cells was increased concomitantly with upregulation of adhesion molecules, but not epithelial to mesenchymal transition markers. Co-cultured cells showed increased proliferation confirmed by downregulation in cell percentage in G0/G1, G2/M and upregulation in S phases of cell cycle. Upregulation of miR-17-5p and 615-5p in co-cultured hA-MSCs was also observed. Functional enrichment analysis of dysregulated proteins in co-cultured hA-MSCs, including our selected miRNAs targets, showed their involvement in development of cancer-associated characteristics. SIGNIFICANCE: This study suggests an interaction between tumor cells and surrounding stromal components to generate cancer associated phenotype of some CAF-like characteristics, known to favor cancer progression. This sheds the light on the use of hA-MSCs in HCC therapy. hA-MSCs modulation may be partially achieved via dysregulation of intracellular miR17-5P and 615-5p expression, suggesting an important role for miRNAs in HCC pathogenesis, and as a possible therapeutic candidate.

Impact of insulin producing cells derived from adipose tissue mesenchymal stem cells on testicular dysfunction of diabetic rats.

The present study is to clarify the effect of insulin-producing cells (IPCs) derived from adipose tissue mesenchymal stem cells (AT-MSCs) on diabetic-induced impairments as the abnormalities of testicular tissues, oxidative stress of testes, and defects of spermatogenesis. Diabetes was stimulated by streptozotocin (STZ) injection in male adult Sprague Dawley (SD) rats. Diabetes was confirmed by taking two highly consecutive fasting blood sugar readings; more than 300 mg/dl; within one week. Five million of IPCs derived from AT-MSCs; encased in TheraCyte capsule; were then directly transplanted (one implant for each rat) subcutaneously in diabetic rats. Implants were maintained for 3 months and the fasting blood sugar of the transplanted rats was observed every month. At the end of the experiment; serum testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were also estimated. The sperm parameters (count, motility, and abnormality) were recorded. In testicular tissue; GPX4, Bcl2, and Bax levels were evaluated, while oxidative stress and antioxidant enzymes activities were measured in the testes homogenate. Also, histopathological alterations were examined in the testes cross-section. In the results, it was found that IPCs treatment enhanced the serum testosterone, FSH, and LH levels. Diabetic-induced impairments in the sperm parameters were noticeably improved post-IPCs transplantation in the diabetic rats. Moreover, the treatment improved the diabetic-associated testicular oxidative stress. Also, it was recognized that the Bax expression decreased, while, GPX4 and Bcl2 expression increased in the treated rats. Meanwhile, the abnormalities showed in the histopathological studies of the hyperglycemic rat's testes were attenuated post-treatment. So, IPCs transplantation improved diabetes and consequently protected against hyperglycemia-induced testicular damages.

Escherichia coli foster bladder cancer cell line progression via epithelial mesenchymal transition, stemness and metabolic reprogramming.

Bacteria is recognized as opportunistic tumor inhabitant, giving rise to an environmental stress that may alter tumor microenvironment, which directs cancer behavior. In vitro infection of the T24 cell line with E. coli was performed to study the bacterial impact on bladder cancer cells. EMT markers were assessed using immunohistochemistry, western blot and RT-PCR. Stemness characteristics were monitored using RT-PCR. Furthermore, the metabolic reprograming was investigated by detection of ROS and metabolic markers. A significant (p ≤ 0.001) upregulation of vimentin as well as downregulation of CK19 transcription and protein levels was reported. A significant increase (p ≤ 0.001) in the expression level of stemness markers (CD44, NANOG, SOX2 and OCT4) was reported. ROS level was elevated, that led to a significant increase (p ≤ 0.001) in UCP2. This enhanced a significant increase (p ≤ 0.001) in PDK1 to significantly downregulate PDH (p ≤ 0.001) in order to block oxidative phosphorylation in favor of glycolysis. This resulted in a significant decrease (p ≤ 0.001) of AMPK, and a significant elevation (p ≤ 0.001) of MCT1 to export the produced lactate to extracellular matrix. Thus, bacteria may induce alteration to the heterogonous tumor cell population through EMT, CSCs and metabolic reprogramming, which may improve cancer cell ability to migrate and self-renew.

From Mesenchymal Stromal/Stem Cells to Insulin-Producing Cells: Progress and Challenges.

Mesenchymal stromal cells (MSCs) are an attractive option for cell therapy for type 1 diabetes mellitus (DM). These cells can be obtained from many sources, but bone marrow and adipose tissue are the most studied. MSCs have distinct advantages since they are nonteratogenic, nonimmunogenic and have immunomodulatory functions. Insulin-producing cells (IPCs) can be generated from MSCs by gene transfection, gene editing or directed differentiation. For directed differentiation, MSCs are usually cultured in a glucose-rich medium with various growth and activation factors. The resulting IPCs can control chemically-induced diabetes in immune-deficient mice. These findings are comparable to those obtained from pluripotent cells. PD-L1 and PD-L2 expression by MSCs is upregulated under inflammatory conditions. Immunomodulation occurs due to the interaction between these ligands and PD-1 receptors on T lymphocytes. If this function is maintained after differentiation, life-long immunosuppression or encapsulation could be avoided. In the clinical setting, two sites can be used for transplantation of IPCs: the subcutaneous tissue and the omentum. A 2-stage procedure is required for the former and a laparoscopic procedure for the latter. For either site, cells should be transplanted within a scaffold, preferably one from fibrin. Several questions remain unanswered. Will the transplanted cells be affected by the antibodies involved in the pathogenesis of type 1 DM? What is the functional longevity of these cells following their transplantation? These issues have to be addressed before clinical translation is attempted. Graphical Abstract Bone marrow MSCs are isolated from the long bone of SD rats. Then they are expanded and through directed differentiation insulin-producing cells are formed. The differentiated cells are loaded onto a collagen scaffold. If one-stage transplantation is planned, a drug delivery system must be incorporated to ensure immediate oxygenation, promote vascularization and provide some growth factors. Some mechanisms involved in the immunomodulatory function of MSCs. These are implemented either by cell to cell contact or by the release of soluble factors. Collectively, these pathways results in an increase in T-regulatory cells.

Subcutaneous transplantation of bone marrow derived stem cells in macroencapsulation device for treating diabetic rats; clinically transplantable site.

BACKGROUND/AIM: Diabetes mellitus (DM) is a serious, chronic and epidemic disease. Its effective therapy with exogenous insulin places an overwhelming burden on the patient's lifestyle. Moreover, pancreatic islet transplantation is limited by the scarceness of donors and the need for chronic immunosuppression. Cell-based therapy is considered an alternative source of insulin-producing cells (IPCs); encapsulating such cellular grafts in immunoisolating devices would protect the graft from immune attack without the need for immunosuppression. Herein, we investigate the ability of TheraCyte capsule as an immunoisolating device to promote the maturation of differentiated rat bone marrow derived mesenchymal stem cells (BM-MSCs), transplanted subcutaneously to treat diabetic rats in comparison with intratesticular transplantation. MAIN METHODS: Rat BM-MSC were differentiated into IPCs, and either encapsulated in TheraCyte capsules for subcutaneous transplantation or transplanted intratesticular into diabetic rats. Serum insulin, C-peptide & blood glucose levels of transplanted animals were monitored. Retrieved cells were further characterized by immunofluorescence staining and gene expression analysis. KEY FINDINGS: Differentiated rat BM-MSC were able to produce insulin in vitro, ameliorate hyperglycemia in vivo and survive for 6 months post transplantation. Transplanted cells induced higher levels of insulin and C-peptide, lower levels of blood glucose in the cured animals of both experimental groups. Gene expression revealed a further in vivo maturation of the implanted cells. SIGNIFICANCE: These data suggest that TheraCyte encapsulation of allogeneic differentiated stem cells are capable of reversing hyperglycemia, which holds a great promise as a new cell based, clinically applicable therapies for diabetes.

PRDX6 Promotes the Differentiation of Human Mesenchymal Stem (Stromal) Cells to Insulin-Producing Cells.

Mesenchymal stem cells (MSCs) can be differentiated in vitro to form insulin-producing cells (IPCs). However, the proportion of induced cells is modest. Extracts from injured pancreata of rodents promoted this differentiation, and three upregulated proteins were identified in these extracts. The aim of this study was to evaluate the potential benefits of adding these proteins to the differentiation medium alone or in combination. Our results indicate that the proportion of IPCs among the protein(s)-supplemented samples was significantly higher than that in the samples with no added proteins. The yield from samples supplemented with PRDX6 alone was 4-fold higher than that from samples without added protein. These findings were also supported by the results of fluorophotometry. Gene expression profiles revealed higher levels among protein-supplemented samples. Significantly higher levels of GGT, SST, Glut-2, and MafB expression were noted among PRDX6-treated samples. There was a stepwise increase in the release of insulin and c-peptide, as a function of increasing glucose concentrations, indicating that the differentiated cells were glucose sensitive and insulin responsive. PRDX6 exerts its beneficial effects as a result of its biological antioxidant properties. Considering its ease of use as a single protein, PRDX6 is now routinely used in our differentiation protocols.

Prediction of recurrence and progression in patients with T1G3 bladder cancer by gene expression of circulating tumor cells.

OBJECTIVE: To investigate the role of gene expression of circulating tumor cells (CTCs) as noninvasive prognostic markers in patients with high risk nonmuscle invasive bladder cancer. MATERIALS AND METHODS: We identified all patients with TIG3 urothelial bladder cancer (UBC) at our institution since 2016.The study included 100 patients with T1G3 UBC and 50 healthy volunteers. CTCs were isolated from blood using immunomagnetic separation and gene expression was performed using 10 bladder cancer associated genes, namely; KRAS, EPCAM, CD133, CD44, mTOR, SURVIVIN, AKT, PI3K, VEGF, and TP53. Gene expression of CTCs was correlated to time to first recurrence and time to progression using Kaplan-Meier curves. RESULTS: There was strong negative correlation between CTCs-positive patients and time to first recurrence and time to progression. Significant differences in expression levels of specific genes were observed that can predict recurrence and progression of T1G3 UBC. CONCLUSION: CTCs appear to be noninvasive methods of predicting disease recurrence and progression in patients with high- risk nonmuscle invasive bladder cancer; therefore, studying their molecular profiling may improve prediction of recurrence and progression. Further studies are invited for more in-depth investigation to consolidate our initial results.

Xeno-free trans-differentiation of adipose tissue-derived mesenchymal stem cells into glial and neuronal cells.

Mesenchymal stem cells (MSCs) are undifferentiated cells that have the ability of self-renewal and trans-differentiation into other cell types. They hold out hope for finding a cure for many diseases. Nevertheless, there are still some obstacles that limit their clinical transplantation. One of these obstacles are the xenogeneic substances added in either proliferation or differentiation media with subsequent immunogenic and infectious transmission problems. In this study, we aimed to replace fetal bovine serum (FBS), the main nutrient source for MSC proliferation with xeno-free blood derivatives. We tested the effect of human activated pure platelet-rich plasma (P-PRP) and advanced platelet-rich fibrin (A-PRF) on the proliferation of human adipose derived-MSCs (AD-MSCs) at different concentrations. For the induction of MSC neural differentiation, we used human cerebrospinal fluid (CSF) at different concentrations in combination with P-PRP to effect xeno-free/species-specific neuronal/glial differentiation and we found that media with 10% CSF and 10% PRP promoted glial differentiation, while media with only 10% PRP induced a neuron-like phenotype.

Secondary metabolites and biological activity of Pentas species: A minireview.

The genus Pentas belongs to the Rubiaceae family, which contains approximately 40 species. Several Pentas species were reported to be used as a folk treatment by African indigenous people in treating some diseases such as malaria, tapeworms, dysentery, gonorrhea, syphilis and snake poisoning. This article covers the period from 1962 to 2017 and presents an overview of the biological activity of different Pentas species and describes their phytochemical traits. As a conclusion, the main secondary metabolites from Pentas species are quinones, highly oxygenated chromene-based structures, and iridoids. Pentas species are widely used in folk medicine but they have to be more investigated for their medicinal properties.

Insulin-producing Cells from Adult Human Bone Marrow Mesenchymal Stromal Cells Could Control Chemically Induced Diabetes in Dogs: A Preliminary Study.

Ten mongrel dogs were used in this study. Diabetes was chemically induced in 7 dogs, and 3 dogs served as normal controls. For each diabetic dog, 5 million human bone marrow-derived mesenchymal stem cells/kg were differentiated to form insulin-producing cells using a trichostatin-based protocol. Cells were then loaded in 2 TheraCyte capsules which were transplanted under the rectus sheath. One dog died 4 d postoperatively from pneumonia. Six dogs were followed up with for 6 to 18 mo. Euglycemia was achieved in 4 dogs. Their glucose tolerance curves exhibited a normal pattern demonstrating that the encapsulated cells were glucose sensitive and insulin responsive. In the remaining 2 dogs, the fasting blood sugar levels were reduced but did not reach normal values. The sera of all transplanted dogs contained human insulin and C-peptide with a negligible amount of canine insulin. Removal of the transplanted capsules was followed by prompt return of diabetes. Intracytoplasmic insulin granules were seen by immunofluorescence in cells from the harvested capsules. Furthermore, all pancreatic endocrine genes were expressed. This study demonstrated that the TheraCyte capsule or a similar device can provide adequate immunoisolation, an important issue when stem cells are considered for the treatment of type 1 diabetes mellitus.

Upregulation of heme oxygenase 1 (HO-1) attenuates kidney damage, oxidative stress and inflammatory reaction during renal ischemia/ reperfusion injury.

The current study investigated the effect of upregulation of heme oxygenase 1 (HO-1) by cobalt protoporphyrin (CoPP) on renal dysfunctions in renal ischemia/reperfusion (I/R) injury and its underlying mechanisms. 72 male Sprague Dawley rats were divided into 4 groups: sham group, ischemic group (left 45-min renal ischemia), CoPP-before group (as ischemic group with CoPP 20 mg/kg 30 min before ischemia) and CoPP-after group (as ischemic group with CoPP 20 mg/kg 20 min after ischemia). Serum creatinine, urea and TGF-ß1 and markers of redox state (MDA, SOD, GSH and CAT), nitric oxide (NO), TGF-ß1 and HO-1 in kidney tissues were measured. Serum creatinine and urea levels were significantly increased in ischemic group and attenuated in CoPP-treated groups (p < 0.05). Also, markers of redox state showed significant deteriorations in ischemic group which were improved significantly in CoPP-treated groups (p < 0.05). HO-1 expression in kidney tissues showed significant increase in ischemic group and showed more significant increase in CoPP-treated groups (p < 0.05). Moreover, serum and renal TGF-ß1 levels were significantly increased in ischemic group and attenuated in CoPP-treated groups (p ≶ 0.05). We concluded that up-regulation of HO-1 by CoPP treatment before and after renal I/R injury improved the kidney function and morphology and this might be due to impairment of oxidative stress and inflammatory cytokines in kidney tissues.

In vitro differentiation of human multilineage differentiating stress-enduring (Muse) cells into insulin producing cells.

Mesenchymal stem cells (MSCs) is a heterogeneous population. Muse cells is a rare pluripotent subpopulation within MSCs. This study aims to evaluate the pulirpotency and the ability of Muse cells to generate insulin producing cells (IPCs) after in vitro differentiation protocol compared to the non-Muse cells. Muse cells were isolated by FACSAria III cell sorter from adipose-derived MSCs and were evaluated for its pluripotency. Following in vitro differentiation, IPCs derived from Muse and non-Muse cells were evaluated for insulin production. Muse cells comprised 3.2 ±â€¯0.7% of MSCs, approximately 82% of Muse cells were positive for anti stage-specific embryonic antigen-3 (SSEA-3). Pluripotent markers were highly expressed in Muse versus non-Muse cells. The percentage of generated IPCs by flow cytometric analysis was higher in Muse cells. Under confocal microscopy, Muse cells expressed insulin and c-peptide while it was undetected in non-Muse cells. Our results introduced Muse cells as a new adult pluripotent subpopulation, which is capable to produce higher number of functional IPCs.

Cancer cell-soluble factors reprogram mesenchymal stromal cells to slow cycling, chemoresistant cells with a more stem-like state.

BACKGROUND: Mesenchymal stem cells (MSCs) play different roles in modulating tumor progression, growth, and metastasis. MSCs are recruited to the tumor site in large numbers and subsequently have an important microenvironmental role in modulating tumor progression and drug sensitivity. However, the effect of the tumor microenvironment on MSC plasticity remains poorly understood. Herein, we report a paracrine effect of cancer cells, in which they secrete soluble factors that promote a more stem-like state in bone marrow mesenchymal stem cells (BM-MSCs). METHODS: The effect of soluble factors secreted from MCF7, Hela, and HepG2 cancer cell lines on BM-MSCs was assessed using a Transwell indirect coculture system. After 5 days of coculture, BM-MSCs were characterized by flow cytometry for surface marker expression, by qPCR for gene expression profile, and by confocal immunofluorescence for marker expression. We then measured the sensitivity of cocultured BM-MSCs to chemotherapeutic agents, their cell cycle profile, and their response to DNA damage. The sphere formation, invasive properties, and in-vivo performance of BM-MSCs after coculture with cancer cells were also measured. RESULTS: Indirect coculture of cancer cells and BM-MSCs, without direct cell contact, generated slow cycling, chemoresistant spheroid stem cells that highly expressed markers of pluripotency, cancer cells, and cancer stem cells (CSCs). They also displayed properties of a side population and enhanced sphere formation in culture. Accordingly, these cells were termed cancer-induced stem cells (CiSCs). CiSCs showed a more mesenchymal phenotype that was further augmented upon TGF-ß stimulation and demonstrated a high expression of the ß-catenin pathway and ALDH1A1. CONCLUSIONS: These findings demonstrate that MSCs, recruited to the tumor microenvironment in large numbers, may display cellular plasticity, acquire a more stem-like state, and acquire some properties of CSCs upon exposure to cancer cell-secreted factors. These acquired characteristics may contribute to tumor progression, survival, and metastasis. Our findings provide new insights into the interactions between MSCs and cancer cells, with the potential to identify novel molecular targets for cancer therapy.

From Human Mesenchymal Stem Cells to Insulin-Producing Cells: Comparison between Bone Marrow- and Adipose Tissue-Derived Cells.

The aim of this study is to compare human bone marrow-derived mesenchymal stem cells (BM-MSCs) and adipose tissue-derived mesenchymal stem cells (AT-MSCs), for their differentiation potentials to form insulin-producing cells. BM-MSCs were obtained during elective orthotopic surgery and AT-MSCs from fatty aspirates during elective cosmetics procedures. Following their expansion, cells were characterized by phenotyping, trilineage differentiation ability, and basal gene expression of pluripotency genes and for their metabolic characteristics. Cells were differentiated according to a Trichostatin-A based protocol. The differentiated cells were evaluated by immunocytochemistry staining for insulin and c-peptide. In addition the expression of relevant pancreatic endocrine genes was determined. The release of insulin and c-peptide in response to a glucose challenge was also quantitated. There were some differences in basal gene expression and metabolic characteristics. After differentiation the proportion of the resulting insulin-producing cells (IPCs), was comparable among both cell sources. Again, there were no differences neither in the levels of gene expression nor in the amounts of insulin and c-peptide release as a function of glucose challenge. The properties, availability, and abundance of AT-MSCs render them well-suited for applications in regenerative medicine. Conclusion. BM-MSCs and AT-MSCs are comparable regarding their differential potential to form IPCs. The availability and properties of AT-MSCs render them well-suited for applications in regenerative medicine.

Nanoformulated natural therapeutics for management of streptozotocin-induced diabetes: potential use of curcumin nanoformulation.

AIM: The goal of this study was to improve curcumin (CUR) aqueous solubility and bioavailability via nanoformulation, and then study its activity and mechanism of action as an antidiabetic agent. METHODS: CUR-loaded pluronic nanomicelles (CURnp) were prepared and characterized. Biochemical assessments were performed as well as histological, confocal and RTPCR studies on pancreatic target tissues. RESULTS: CURnp with a diameter of 333 ± 6 nm and ζ potential of -26.1 mv were obtained. Antidiabetic action of CURnp was attributed to significant upregulation of Pdx-1 and NKx6.1 gene expression and achievement of optimum redox balance, which led to alleviation of streptozotocin-induced ß-cell damage via a significant upregulation in insulin gene expression proved by RTPCR studies and by the presence of 40% insulin positive cells through confocal microscope studies on pancreatic tissue.

A newly developed silymarin nanoformulation as a potential antidiabetic agent in experimental diabetes.

AIM: This study aimed to develop a new stable nanoformulation of silymarin (SM) with optimum enhanced oral bioavailability and to evaluate its effect as well as mechanism of action as a superior antidiabetic agent over native SM using streptozotocin-induced diabetic rats. MATERIALS AND METHODS: SM-loaded pluronic nanomicelles (SMnp) were prepared and fully characterized. Biochemical parameters were performed as well as histological, confocal and reverse-transcription polymerase chain reaction studies on pancreatic target tissues. RESULTS & CONCLUSION: SMnp were found to improve significantly the antihyperglycemic, antioxidant and antihyperlipidemic properties as compared with native SM. In addition, SMnp was found to be a more efficient agent over SM in the management of diabetes and its associated complications due to its superior bioavailability in vivo, and the controlled release profile of SM. [Formula: see text].