Correlation of PD-L1 immunohistochemical expression with microsatellite instability and p53 status in endometrial carcinoma.

Background: Endometrial carcinoma (EC) is the most common gynaecological cancer worldwide. The Cancer Genome Atlas molecular grouping of a given case of EC could be assessed by POLE gene mutation, mismatch repair (MMR) 'to reflect microsatellite instability' and p53 status, which has proved to be of prognostic value. Programmed cell death receptor 1 (PD-1) and its ligand (PD-L1) are playing a progressively important role in tumour immunology and cancer treatment. Objectives: To investigate PD-L1 immunohistochemical expression in EC in relation to MMR and p53 status. Associations between marker expression and different histopathological parameters were also investigated. Methods: This retrospective study was performed on archival biopsies of 170 cases of EC using a tissue microarray model. Immunohistochemical staining was applied using antibodies against PD-L1, MLH1, MSH2 and p53. Results: The percentages of positivity were as follows: PD-L1, 19.6%; MLH1, 79.5%; MSH2, 78.5%; and p53 mutant, 13.8%. There was significant correlation between MLH1 expression and MSH2 expression (p = 0.008). Tumour grade was significantly correlated with stage (p = 0.005) and p53 mutant expression (p = 0.008). Combined PD-L1 positivity and MMR deficiency showed significant correlation with the presence of lymphovascular space invasion (p = 0.014). MSH2 negativity was significantly associated with poorer overall survival (p = 0.014). Conclusions: A panel of immunohistochemical markers (PD-L1, MLH1, MSH2 and p53) could help to predict the prognosis and plan the treatment of patients with EC. MMR deficiency seems to be a good predictor for PD-L1 status, and therefore the response to potential PD-1/PD-L1 inhibitor therapy.

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.

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.

Potential Role for a Panel of Immunohistochemical Markers in the Management of Endometrial Carcinoma.

BACKGROUND: In order to improve the efficacy of endometrial carcinoma (EC) treatment, identifying prognostic factors for high risk patients is a high research priority. This study aimed to assess the relationships among the expression of estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor 2 (HER2), Ki-67, and the different histopathological prognostic parameters in EC and to assess the value of these in the management of EC. METHODS: We examined 109 cases of EC. Immunohistochemistry for ER, PR, HER2, and Ki-67 were evaluated in relation to age, tumor size, International Federation of Gynecology and Obstetrics (FIGO) stage and grade, depth of infiltration, cervical and ovarian involvement, lymphovascular space invasion (LVSI), and lymph node (LN) metastasis. RESULTS: The mean age of patients in this study was 59.8 ± 8.2 years. Low ER and PR expression scores and high Ki-67 expression showed highly significant associations with non-endometrioid histology (p = .007, p < .001, and p < .001, respectively) and poor differentiation (p = .007, p < .001, and p <. 001, respectively). Low PR score showed a significant association with advanced stage (p = .009). Low ER score was highly associated with LVSI (p = .006), and low PR scores were associated significantly with LN metastasis (p = .026). HER2 expression was significantly related to advanced stages (p = .04), increased depth of infiltration (p = .02), LVSI (p = .017), ovarian involvement (p = .038), and LN metastasis (p = .038). There was a close relationship between HER2 expression and uterine cervical involvement (p = .009). Higher Ki-67 values were associated with LN involvement (p = .012). CONCLUSIONS: The over-expression of HER2 and Ki-67 and low expression of ER and PR indicate a more malignant EC behavior. An immunohistochemical panel for the identification of high risk tumors can contribute significantly to prognostic assessments.

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.

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.

The novel c-Met inhibitor capmatinib mitigates diethylnitrosamine acute liver injury in mice.

The receptor tyrosine kinase mesenchymal-epithelial transition factor (c-Met) sits at the interface between controlled cellular division of organogenesis and uncontrolled cellular division of carcinogenesis. c-Met contribution to the initial phases of liver injury and inflammation is still not resolved. Herein, we investigated the selective pharmacological intervention of c-Met by capmatinib (formerly known as INC280) in the diethylnitrosamine (DEN) acute liver injury model in mice. c-Met inhibition by capmatinib reduced DEN-induced elevation of the pro-inflammatory cytokines TNF-α, IL-1ß, IL-17A, IL-23(p19/40) and IFN-γ, which correlated well with serum markers of hepatocellular injury (ALT, AST and LDH). The protective effects possessed by capmatinib were mainly mediated by inhibiting inflammatory cells infiltration to the liver. However, hematoxylin-eosin and bax-immunohistochemical stainings revealed that capmatinib (at a dose of 10, but not 5mg/kg) aggravated DEN-induced hepatocellular ballooning and apoptosis, respectively. These effects were concordant with hepatocellular overexpression of the amino acid transporter CD98. Such capmatinib effects arised mostly from exaggerating the elevation of the mutagenic lipid peroxide 4-HNE along with MDA that enhanced DEN-induced compensatory proliferation evidenced by PCNA expression. In conclusion, inhibition of c-Met activation by capmatinib may provide protection against liver injury, but may trigger undesirable elevation of the mutagenic 4-HNE.

Inhibition of the JAK/STAT pathway by ruxolitinib ameliorates thioacetamide-induced hepatotoxicity.

In an attempt to explore the role of the JAK/STAT pathway in liver inflammation, we investigated the effect of intervening this pathway by ruxolitinib in thioacetamide (TAA)-induced hepatotoxicity. Ruxolitinib treatments were administered to male mice either before or after intoxication with TAA. The hepatic histopathological and serum biochemical assessment revealed that ruxolitinib pre-treatments dose-dependently reduced TAA-induced liver injury, caspase 3 cleavage and increase in number of hepatocytes positive for the pro-apoptotic Bax, as well as inflammatory cells positive for F4/80 and myeloperoxidase activity in the liver. Ruxolitinib pre-treatments also curbed TAA-induced rise in NF-κB nuclear expression and STAT3 phosphorylation. Ruxolitinib pre-treatments also lowered TAA-induced elevation of hepatic oxidative stress parameters (total nitrate/nitrite and 4-hydroxynonenal), but did not restore the hepatic antioxidant reduced glutathione. Interestingly, ruxolitinib, especially at a dose of 200 mg/kg, dampened the overproduction of pro-inflammatory cytokines (TNF-α, IL-1ß, IFN-γ, IL-23 and IL-17A), which coincided with boosting the release of the anti-inflammatory cytokine IL-10. Ruxolitinib when used as a post-treatment (1 and 3 h after TAA-insult) could still spare the liver from injury and might be clinically applicable. In conclusion, the multimechanistic-hepatoprotective activity of ruxolitinib can be linked to its ameliorative properties on cellular death, oxidative stress and inflammation machinery.

Differentiation of Human Bone Marrow-Derived Mesenchymal Stem Cells into Insulin-Producing Cells: Evidence for Further Maturation In Vivo.

The aim of this study was to provide evidence for further in vivo maturation of insulin-producing cells (IPCs) derived from human bone marrow-derived mesenchymal stem cells (HBM-MSCs). HBM-MSCs were obtained from three insulin-dependent type 2 diabetic volunteers. Following expansion, cells were differentiated according to a trichostatin-A/GLP protocol. One million cells were transplanted under the renal capsule of 29 diabetic nude mice. Blood glucose, serum human insulin and c-peptide levels, and glucose tolerance curves were determined. Mice were euthanized 1, 2, 4, or 12 weeks after transplantation. IPC-bearing kidneys were immunolabeled, number of IPCs was counted, and expression of relevant genes was determined. At the end of in vitro differentiation, all pancreatic endocrine genes were expressed, albeit at very low values. The percentage of IPCs among transplanted cells was small (≤3%). Diabetic animals became euglycemic 8 ± 3 days after transplantation. Thereafter, the percentage of IPCs reached a mean of ~18% at 4 weeks. Relative gene expression of insulin, glucagon, and somatostatin showed a parallel increase. The ability of the transplanted cells to induce euglycemia was due to their further maturation in the favorable in vivo microenvironment. Elucidation of the exact mechanism(s) involved requires further investigation.

The novel Janus kinase inhibitor ruxolitinib confers protection against carbon tetrachloride-induced hepatotoxicity via multiple mechanisms.

Therapeutic targeting of the JAK/STAT pathway, the principal signaling mechanism for numerous cytokines, might be an effective approach for limiting inflammation in different organs, including the liver. Therefore, we investigated whether targeting this pathway by the novel JAK inhibitor ruxolitinib could mitigate hepatic damage provoked by carbon tetrachloride (CCl4). Male mice received ruxolitinib treatments (75 and 150 mg/kg, oral) 2 h prior to intoxication with CCl4 (10 ml/kg of 0.3% v/v CCl4 solution in olive oil, intraperitoneal) for 24 h. Our results showed that ruxolitinib treatments dose-dependently alleviated CCl4-induced hepatic injury and necroinflammation, as indicated by biochemical markers of injury and histopathology. We unraveled also the mechanisms involved in these hepatoprotective effects. These comprise (i) reducing infiltration of neutrophils and macrophages, as demonstrated by reducing myeloperoxidase activity and F4/80 positive macrophages; (ii) abating apoptosis of hepatocytes, as denoted by decreasing hepatocytes positive for Bax protein; (iii) inhibiting elevation of TNF-α, IL-1ß and IL-10; (iv) inhibiting NF-κB activation and translocation to the nucleus, as visualized immunohistochemically; (v) attenuating activation of the IL-23/IL-17 pathway via targeting IL-17, but not IL-23; (vi) antagonizing hepatic oxidative stress by increasing the antioxidant levels (reduced glutathione, glutathione-S-transferase and superoxide dismutase) and decreasing products of lipid peroxidation (malondialdehyde and 4-hydroxynonenal) and total nitrate/nitrite; and (vii) more interestingly, modulating hepatocyte regeneration according to the extent of damage, as quantified by PCNA-immunohistochemistry. In conclusion, our study sheds light on the therapeutic usefulness and the potential underlying mechanisms of the novel JAK inhibitor ruxolitinib in hepatic inflammatory disorders.

Generation of insulin-producing cells from human bone marrow-derived mesenchymal stem cells: comparison of three differentiation protocols.

INTRODUCTION: Many protocols were utilized for directed differentiation of mesenchymal stem cells (MSCs) to form insulin-producing cells (IPCs). We compared the relative efficiency of three differentiation protocols. METHODS: Human bone marrow-derived MSCs (HBM-MSCs) were obtained from three insulin-dependent type 2 diabetic patients. Differentiation into IPCs was carried out by three protocols: conophylline-based (one-step protocol), trichostatin-A-based (two-step protocol), and ß -mercaptoethanol-based (three-step protocol). At the end of differentiation, cells were evaluated by immunolabeling for insulin production, expression of pancreatic endocrine genes, and release of insulin and c-peptide in response to increasing glucose concentrations. RESULTS: By immunolabeling, the proportion of generated IPCs was modest ( ≃ 3%) in all the three protocols. All relevant pancreatic endocrine genes, insulin, glucagon, and somatostatin, were expressed. There was a stepwise increase in insulin and c-peptide release in response to glucose challenge, but the released amounts were low when compared with those of pancreatic islets. CONCLUSION: The yield of functional IPCs following directed differentiation of HBM-MSCs was modest and was comparable among the three tested protocols. Protocols for directed differentiation of MSCs need further optimization in order to be clinically meaningful. To this end, addition of an extracellular matrix and/or a suitable template should be attempted.

Celastrol ameliorates murine colitis via modulating oxidative stress, inflammatory cytokines and intestinal homeostasis.

Therapeutic agents that block the nuclear factor-kappa B (NF-κB) pathway might be beneficial for incurable inflammatory diseases, such as ulcerative colitis. Here, we investigated the effect of the novel NF-κB inhibitor celastrol on murine colitis. Colitis was induced in male mice by administration of 5% (w/v) dextran sulfate sodium (DSS) in drinking water for a period of 5 days, followed by a 2 day recovery period. Celastrol (2mg/kg, oral) was administered daily over the 1 week of the study. Our results indicated that treatment with celastrol attenuated DSS-induced colon shortening and neutrophil infiltration. Besides, celastrol ameliorated DSS-induced colon injury and inflammatory signs as visualized by histopathology. The mechanisms behind these beneficial effects of celastrol were also elucidated. These include (i) counteracting DSS-induced oxidative stress in the colon via decreasing lipid peroxidation products (malondialdehyde and 4-hydroxynonenal) and increasing the antioxidant levels (reduced glutathione, glutathione-S-transferase and superoxide dismutase); (ii) inhibiting DSS-induced activation of the NLRP3-inflammasome, as evidenced by decreased production of IL-1ß and IFN-γ as indirect measure of IL-18 in the colon; (iii) targeting DSS-induced activation of the IL-23/IL-17 pathway by abating the elevation of IL-23 and IL-17A levels in the colon; (iv) augmenting the anti-inflammatory defense mechanisms via increasing IL-10 and TNF-α levels in the colon; (v) and more importantly, maintaining intestinal epithelial reconstitution and homeostasis via attenuating the overexpression of CD98 in colonic epithelial cells. In conclusion, our study provides novel insights into the beneficial effects of celastrol as a promising candidate for the treatment of ulcerative colitis in humans.

Atypical meningioma: a study of prognostic factors.

OBJECTIVE: Atypical meningiomas represent 20% of all meningiomas. This retrospective study analyzes the prognostic factors, the effect of different methods of treatments, and the behavior of atypical meningiomas. METHODS: The study comprised 44 patients who were given a diagnosis of atypical meningioma according to the 2007 World Health Organization classification in the period from January 2009 to March 2012. Data collected included patient age, gender, tumor location, presenting symptoms, and treatment received. Patients were followed to detect recurrence and assess survival. RESULTS: Median overall survival was 57 months, with a 5-year survival of 35%. Significantly better survival was observed for patients <50 years old (65 months vs. 46 months, P = 0.033) and patients with total resection (Simpson grade 1-2) compared with subtotal resection (Simpson grade 3-4) or biopsy (Simpson grade 5) (75 months vs. 46 months and 24 months, P < 0.0001). Patients with a tumor located in brain convexity had better survival but with no statistical significance (P = 0.052). Multivariate analysis showed prognostic significance with age (P = 0.030) and extent of resection (P < 0.000). Progression-free survival ranged from 7-83 months with a median of 39 months. Progression-free survival showed a significant relationship with subtotal resection compared with biopsy (P = 0.007). Recurrences were less in patients who received radiotherapy (RT), and this was statistically significant (P = 0.007). CONCLUSIONS: Long-term survival is possible for patients with atypical meningiomas treated with surgery and postoperative RT. Multivariate analysis confirmed that age (<50 years) and total surgical excision were independent prognostic factors for survival. Adjuvant RT reduces tumor recurrence, especially after incomplete surgery.

Insulin-producing cells from adult human bone marrow mesenchymal stem cells control streptozotocin-induced diabetes in nude mice.

Harvesting, expansion, and directed differentiation of human bone marrow-derived mesenchymal stem cells (BM-MSCs) could provide an autologous source of surrogate ß-cells that would alleviate the limitations of availability and/or allogenic rejection following pancreatic or islet transplantation. Bone marrow cells were obtained from three adult type 2 diabetic volunteers and three nondiabetic donors. After 3 days in culture, adherent MSCs were expanded for two passages. At passage 3, differentiation was carried out in a three-staged procedure. Cells were cultured in a glucose-rich medium containing several activation and growth factors. Cells were evaluated in vitro by flow cytometry, immunolabeling, RT-PCR, and human insulin and c-peptide release in responses to increasing glucose concentrations. One thousand cell clusters were inserted under the renal capsule of diabetic nude mice followed by monitoring of their diabetic status. At the end of differentiation, ∼5-10% of cells were immunofluorescent for insulin, c-peptide or glucagon; insulin, and c-peptide were coexpressed. Nanogold immunolabeling for electron microscopy demonstrated the presence of c-peptide in the rough endoplasmic reticulum. Insulin-producing cells (IPCs) expressed transcription factors and genes of pancreatic hormones similar to those expressed by pancreatic islets. There was a stepwise increase in human insulin and c-peptide release by IPCs in response to increasing glucose concentrations. Transplantation of IPCs into nude diabetic mice resulted in control of their diabetic status for 3 months. The sera of IPC-transplanted mice contained human insulin and c-peptide but negligible levels of mouse insulin. When the IPC-bearing kidneys were removed, rapid return of diabetic state was noted. BM-MSCs from diabetic and nondiabetic human subjects could be differentiated without genetic manipulation to form IPCs that, when transplanted, could maintain euglycemia in diabetic mice for 3 months. Optimization of the culture conditions are required to improve the yield of IPCs and their functional performance.