Ve Cells Research Articles

Morphological and Biochemical Features of Cerebellar Cortex After Exposure to Zinc Oxide Nanoparticles: Possible Protective Role of Curcumin.

Zinc oxide nanoparticles (ZnONPs) are widely used in the last decades. Therefore, investigation of its neurotoxic effect is important. This work aimed to investigate the potential adverse effects of ZnONPs on rat's cerebellar cortex and the possible neuroprotective role of curcumin (Cur). Forty male albino rats were randomly divided into four equal groups. Two groups were injected with ZnONPs and one group was previously received Cur before ZnONPs. At the end of the experiment, cerebellar tissue samples were prepared for histological, morphometric, immunohistochemical study, and tissue levels of oxidative stress markers and cytokine analysis. cerebellar damage is clearly visible with ZnONPs. Degeneration, loss, disorganization of cerebellar neurons was observed. Histopathological degeneration of Purkinje and granular cells together with loss of Nissl substance, astrocyte gliosis, and affection of cerebellar blood brain barrier were detected. Moreover, an apoptotic marker (caspase-3) was significantly expressed in Purkinje and granular layers together with elevated gene expression of P53 and COX-2 in cerebellar tissue of ZnONPs intoxicated group. Astrocyte gliosis and inflammatory markers IL-1, IL-6, and TNF-α were expressed significantly in ZnONPs intoxicated cerebellum. These changes were associated with evidence of cerebellar oxidative stress. Strikingly, treatment with Cur together with ZnONPs recorded morphological improvement, with increased number of Purkinje cells and decreased caspase +ve cells. These findings were confirmed by morphometric and statistical analysis. Cur ameliorates the deterious effect of ZnONPs on the cerebellar cortex through its antioxidant, antiapoptotic, and anti-inflammatory efficacies. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.

DNA methylation regulated microRNAs in HPV-16-induced head and neck squamous cell carcinoma (HNSCC).

Epigenetic modifications have been reported to play an important role in regulating gene expression and these modifications become critical when they have a role in controlling another important layer of epigenetic regulation namely microRNAs. In the present study, we have identified the microRNAs that may be regulated by promoter DNA methylation and histone acetylation in Human papilloma virus-positive head and neck squamous cell carcinoma. HPV-negative cell line (UPCI:SCC-116) and HPV-16 +ve cell line (UPCI:SCC-090) were treated with methylation inhibitor (5-aza-2'-deoxycytidine, AZA) and acetylation inhibitor (Trichostatin-A, TSA), followed by micro-array analysis. The differentially expressed miRNAs were validated in control (n = 10), HPV-16 +ve (n= 30), and HPV -ve (n = 30) HNC, TCGA (n = 529) tissue samples, and two HPV -ve (SCC116 and Hacat) and two HPV +ve (SCC090 and SiHa) cell lines. Methylation-specific PCR (MSP) and chromatin immunoprecipitation assay (CHIP) were performed to validate their regulation. In silico and in vitro analyses of identified miRNAs were done to study putative pathways they target and their possible role in carcinogenesis. Among 10 miRNAs specifically up-regulated in microarray analysis of AZA-treated SCC090 cells, we observed significantly decreased expression of hsa-miR-181c-5p, hsa-miR-132-5p, hsa-miR-658 in HPV +ve HNC cohort, TCGA tissue samples, and cell lines as compared to their HPV -ve counterpart, and their promoter region also possesses CpG islands. MSP and analysis of TCGA data (MethHC) revealed increased frequency of methylation at the promoter of hsa-miR-132-5p that is negatively correlated with its expression. In TSA-treated SCC090 cells, out of 7 miRNAs, two namely Hsa-miR-129-2-3p and Hsa-miR-449a were found to be up-regulated as compared to HPV -ve cells. However, the levels of enrichment by anti-acetyl-H3 and anti-acetyl-H4 were significantly low in cell lines compared to respective controls and both were up-regulated in HPV +ve compared to HPV -ve TCGA tissue samples. In silico analysis revealed hsa-miR-132-5p targeted canonical β-catenin/wnt pathway and modulation of down-stream genes of the pathway was observed on over-expression/inhibition of hsa-miR-132-5p. This study suggests the role of epigenetic modifications in regulating expression of miRNAs in HPV +ve HNSCC.

Regulation of Gastric Lgr5+ve Cell Homeostasis by Bone Morphogenetic Protein (BMP) Signaling and Inflammatory Stimuli.

Background & AimsGastric Leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) cells exert important functions during injury and homeostasis. Bone morphogenetic protein (BMP) signaling regulates gastric inflammation and epithelial homeostasis. We investigated if BMP signaling controls the fate of Lgr5+ve cells during inflammation.MethodsThe H+/K+-adenosine triphosphatase β-subunit promoter was used to express the BMP inhibitor noggin (Nog) in the stomach (H+/K+-Nog mice). Inhibition of BMP signaling in Lgr5 cells was achieved by crossing Lgr5-EGFP-ires-CreERT2 (Lgr5-Cre) mice to mice with floxed alleles of BMP receptor 1A (Lgr5-Cre;Bmpr1aflox/flox mice). Lgr5/GFP+ve cells were isolated using flow cytometry. Lineage tracing studies were conducted by crossing Lgr5-Cre mice to mice that express Nog and tdTomato (Lgr5-Cre;H+/K+-Nog;Rosa26-tdTom). Infection with Helicobacter felis was used to induce inflammation. Morphology of the mucosa was analyzed by H&E staining. Distribution of H+/K+-adenosine triphosphatase-, IF-, Ki67-, CD44-, CD44v9-, and bromodeoxyuridine-positive cells was analyzed by immunostaining. Expression of neck and pit cell mucins was determined by staining with the lectins Griffonia (Bandeiraea) simplicifolia lectin II and Ulex europaeus agglutinin 1, respectively. Id1, Bmpr1a, Lgr5, c-Myc, and Cd44 messenger RNAs were measured by quantitative reverse-transcription polymerase chain reaction.ResultsLgr5-Cre;Bmpr1aflox/flox mice showed diminished expression of Bmpr1a in Lgr5/GFP+ve cells. Infection of Lgr5-Cre;Bmpr1aflox/flox mice with H felis led to enhanced inflammation, increased cell proliferation, parietal cell loss, and to the development of metaplasia and dysplasia. Infected Lgr5-Cre;H+/K+-Nog;Rosa26-tdTom mice, but not control mice, showed the presence of tomato+ve glands lining the lesser curvature that stained positively with Griffonia (Bandeiraea) simplicifolia lectin II and Ulex europaeus agglutinin 1, and with anti-IF, -CD44, -CD44v9, and -bromodeoxyuridine antibodies.ConclusionsInflammation and inhibition of BMP signaling activate Lgr5+ve cells, which give rise to metaplastic, dysplastic, proliferating lineages that express markers of mucus neck and zymogenic cell differentiation.

Cytokine Syntheses by T-Cell Subsets From Chronic Myeloid Leukemia Patients: Relationship Between Pre-Treatment Levels and Response to Imatinib Therapy.

BackgroundAlthough T-cell cytokine’s role in the long-term control of chronic myeloid leukemia (CML) is well established, previous studies showed contradicting results regarding imatinib (IM) effect on the endogenous T-cell function by IM. The purpose of this study was to determine the relation between the endogenous T-cell function prior to therapy and the degree of response to IM therapy in CP CML. In addition, modulation of the endogenous T-cell function during IM therapy was studied.MethodsWe evaluated Th1 (gamma interferon (IFN-γ)), Th2 (interleukin (IL-4)) and tumor necrosis factor (TNF)-α cytokine synthesis by activated T-cell subsets in 20 patients with newly diagnosed CML in chronic phase (CP CML) using flow cytometry before and during IM therapy compared to patients with IM resistance (IM Res) and healthy donors.ResultsPatients with optimal response (CML OR) to IM demonstrated a lower pre-treatment Th1 cytokine compared to that of healthy donors, and a higher percentage of Th2 and TNF-α producing T cells compared to that of healthy donors, non-optimal responders (CML nOR) and those with IM Res. A shift from Th2 profile to Th1 profile and initial decline of TNF-α producing T cells was detected early during therapy in optimal responders which was coinciding with complete hematological remission with a significant increase in the percentages of CD4+ve/IFN-γ+ve cells (P = 0.01) and a significant drop of in CD8+ve/IL-4+ve T cells (P = 0.04).ConclusionWe believe that pre-treatment levels of IL-4 and/or TNF-α may have a role in identifying CP CML patients who may respond to IM therapy; however, further investigation is needed.

CXCL‐10 and Interleukin‐6 are reliable serum markers for vitiligo activity: A multicenter cross‐sectional study

This cross-sectional multicenter study aimed to evaluate serum CXCL-10, as an activity marker for vitiligo, and compare it with other putative serum and tissue markers. Serum CXCL-10 was compared to interferon gamma (IFN-γ), interleukin 6 (IL-6), and IL-17 using ELISA in 55 non-segmental vitiligo patients (30 active and 25 stable) and 30 healthy controls. Marginal skin biopsy was taken for immunohistochemical evaluation of CD8+T cells and CXCL-10+ve cells. Serum levels of CXCL-10, IL-17, and IL-6 were elevated in all vitiligo patients compared to controls (p<.05). All investigated serum markers were higher in active versus stable vitiligo. Tissue expression of CXCL-10+ve cells and CD8+ve T cells was stronger in vitiligo patients compared to controls, and tissue CXCL-10+ve cell expression was stronger in active versus stable cases. Positive correlations were noted between the different serum and tissue markers. CXCL-10 was the most specific, whereas IL-6 was the most sensitive serum marker to distinguish active from stable disease.

Allogeneic Descemet's Membrane Transplantation Enhances Corneal Endothelial Monolayer Formation and Restores Functional Integrity Following Descemet's Stripping.

To characterize the differences in corneal endothelial wound healing in the presence or absence of Descemet's membrane (DM), in vivo. New-Zealand white rabbits were subjected to 7-mm endothelial wound either by scraping (n = 8; DM intact), peeling (n = 6; DM removed), or a combinatory scrape/peel wound (n = 6). In a second experiment, rabbits underwent peel wound with immediate transplantation of pure decellularized human DM (n = 4). In vivo endothelial migration was assessed via trypan blue staining. Recovery of corneal clarity and thickness was performed by using slit-lamp biomicroscopy and optical coherence tomography. Cell proliferation, phenotype, and morphology were assessed by using immunofluorescence and scanning electron microscopy. In vivo wound closure was faster in the presence of DM; 25.4% ± 1.4%/d versus 5.5% ± 0.6%/d (P < 0.0001). At day 8, complete wound closure was seen in all of the scrape samples but none of the peel group, with wound closure preceding clinical recovery by approximately 6 days in the scrape group. Endothelial cells in the scraped areas reformed functional monolayers capable of restoring corneal thickness and transparency whilst those in the peeled area underwent mesenchymal-like transformation resulting in scar formation. Transplanting decellularized DM in animals receiving a peel wound resulted in clarity and thickness comparable to the scrape group. Endothelial proliferation (Ki67 +ve cells) was higher in scraped versus peeled areas: 54.7% ± 3.5% vs. 8.8% ± 0.7%, (P < 0.01). The presence of DM promoted endothelial wound healing, proliferation, and maintenance of a normal phenotype. DM transplantation recovered the abnormal peel phenotype back to that observed after endothelial scraping.

Garlic extract and phonophoresis in wound healing: Histological and immunohistochemical study

Background: Garlic extract can be used alongside conventional antibiotics to fight agents of nosocomial infections, prevalent in hospitals. Phonophoresis is the use of therapeutic ultrasound to increase the percutaneous absorption of pharmacologic agents.Aim of the work: To compare between the use of garlic extract with and without phonophoresis in wound healing in male albino rats.Material & methods: Twenty four male albino rats were classified into 4 equal groups. Group I included 6 rats used as the control group. Group II; 6 rats subjected to wound injury; of them 3 were sacrificed after 2weeks (subgroup-IIa) and the other 3 rats were sacrificed after 3 weeks (subgroup IIb). Group III (Garlic-extract treated) included 6 rats subjected to wound injury and received garlic extract gel daily. Of them, 3 rats and were sacrificed after 2weeks of treatment (subgroup-IIIa). The other 3 rats were sacrificed after 3 weeks of teatment (subgroup-IIIb). Group IV (Garlic extract /Phonophoresis, both) 6 rats subjected to wound injury and received garlic extract gel daily together with phonophoresis 3 times/week. Of which, 3 rats sacrificed after 2 weeks (subgroup-IVa) and 3 rats were sacrificed after 3 weeks (subgroup-IVb). The wound surface areas were measured. Skin sections were processed for histological, immunohistochemical and morphometric studies.Results: Examination of skin sections in the wound group (group II) showed wide separation of edges and few hair follicles with reduced thickness and desquamated keratin. In group III and group IV, there was marked regeneration of the epidermis and dermis. With significant increase in hair follicles number in group IV compared to group III. Multiple immunostained CD44 +ve cells were detected in group IV.Conclusion: Both garlic and phonophoresis helped wound healing but Garlic extract/phonophoresis combination revealed faster and better (i.e., more complete wound) healing compared to garlic extract application without phonophoresis.

Abstract 1711: Detection of circulating tumor cells for use as prognostic, predictive and pharmacodynamic biomarkers in neuroblastoma

Abstract Introduction: Neuroblastoma (NB) is the commonest extracranial childhood solid tumour. New treatments and a better understanding of drug resistance are needed to improve survival. Circulating tumour cells (CTCs) may provide a source of tumour cells for genetic biomarkers, give insights into tumour load and serve as pharmacodynamic (PD) biomarkers for new treatments. In clinical diagnostics, slide based FISH is used to detect MYCN amplification in neuroblastoma tumours. As it is not possible to conduct slide based FISH on an entire blood sample due to the infrequency of CTCs in peripheral blood (1 in 106 leucocytes), an alternative method FISH-IS (in suspension) was used in the present study to detect MYCN gene amplification using the Imagestream imaging flow cytometer (ISx). Aims: 1) To detect CTCs from blood and disseminated tumour cells (DTC) from bone marrow (BM) from NB patients using the (ISx) 2) To use these cells for genetic and PD biomarker studies for novel targeted therapies. Methods: A panel of NB cell lines (n=6) cloned into neuronal (N) and substrate-adherent (S) types were used to determine expression of NB cell surface markers (GD2 and NCAM) using the ISx. Western blotting and fluorescence activated cell sorting (FACS) were used to validate NCAM and GD2 expression respectively. 25 paired NB patient blood and BM samples were analysed for CTCs and DTCs, 4 unpaired blood samples were analysed for CTCs and one unpaired BM sample was for DTCs using the ISx to detect GD2 +ve and CD45-ve cells. Results: Using the ISx 80-90% of N-type cells immunostained positive for GD2 compared to 0.8 -10% of S-type cells confirmed by FACS. CTCs were detected in 21/29 patient samples and DTCs in 19/26 cases. The numbers of CTCs ranged from 10-522/ml blood and DTCs from 57-35,515/ml of bone marrow. After validating FISH-IS protocol on ISx using NGP and SHSY5Y cell lines, 4 NB patient DTC samples were analysed for MYCN amplification. 2/4 cases showed MYCN gene amplification consistent with results obtained on the primary tumour. Conclusion: This the first study to show that DTCs and CTCs are detectable in NB patient samples using the ISx. Future work will involve further genetic characterisation and development of PD biomarkers for Phase I clinical trials. Citation Format: Swathi Merugu, Deborah Tweddle. Detection of circulating tumor cells for use as prognostic, predictive and pharmacodynamic biomarkers in neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1711. doi:10.1158/1538-7445.AM2017-1711

Effects of acute altered gravity during parabolic flight and/or vestibular loss on cell proliferation in the rat dentate gyrus.

Both parabolic flight, i.e. a condition of altered gravity, and loss of vestibular function, have been suggested to affect spatial learning and memory, which is known to be influenced by neurogenesis in the hippocampus. In this study we investigated whether short alternated micro- and hyper-gravity stimulations during parabolic flight and/or loss of vestibular function, would alter cell proliferation in the hippocampal dentate gyrus of rats, by measuring the number of bromodeoxyuridine (BrdU)-incorporated cells. Rats were randomly allocated to the following experimental groups: (1) sham transtympanic saline injection only (n=5); (2) bilateral vestibular deafferentation (BVD) by sodium arsanilate transtympanic injection only (n=5); (3) sham treatment and parabolic flight (n=5); (4) BVD and parabolic flight (n=6). Forty-two days following transtympanic injection, the animals were subjected to parabolic flight in an awake restrained condition after habituation. A modified Airbus A300 aircraft was flown on a parabolic path, creating 20s of 1.8G during both climbing and descending and 22s of 0G at the apex of each parabola. The no flight animals were subjected to the same housing for the same duration. Immediately after the parabolic flight or control ground condition, animals were injected with BrdU (300mg/kg, i.p). Twenty-four hs after BrdU injection, rats were sacrificed. BrdU immunolabelling was performed and the number of BrdU+ve cells in the dentate gyrus of the hippocampus was quantified using a modified fractionator method. BVD caused a large and significant reduction in the number of BrdU-positive cells compared to sham animals (P≤0.0001); however, flight and all interactions were non-significant. These results indicate that BVD significantly decreased cell proliferation irrespective of the short exposure to altered/modified gravity.

Association between insulin-like growth factor-1 receptor (IGF1R) expression in circulating tumor cells (CTCs) and prognosis in patients with metastatic breast cancer (MBC).

1086 Background: CTCs are strongly associated with prognosis in MBC. In a recent metanalysis on 1944 patients, a CTC count &gt; 5/7.5 ml was associated with a 2-fold increased risk of progression and death. Little evidence is available on the prognostic role of phenotypic CTC assessment, however. In this study, nested in a randomized clinical trial of Ist line chemotherapy ± metformin, we evaluated the prognostic role of IGF1R expression in CTCs, given its potential growth promoting effect. Methods: CTCs were isolated from blood samples of enrolled patients; an automated sample preparation and analysis system (CellSearch) was customized for detecting IGF1R positive CTCs. The prognostic role of total CTCs, IGF1R positive (+ve) and negative (-ve) CTCs was assessed by fitting different PFS and OS multivariate Cox’s models.Results: CTC evaluation at baseline was performed in 72 of 126 patients, of whom 30 (42%) had CTCs ≥5/7,5ml and 41 (57%) had at least one IGF1R+ve CTC. In univariate analysis the prognostic role of total CTCs was confirmed: PFS ( &lt; 5 vs ≥5) HR = 1.69, 95%CI 1.01-2.69, p 0.042 and OS HR = 2.80, 95%CI 1.47-5.30, p 0.002).However, when total CTCs were split in IGF1R+ve and IGF1R–ve, a striking difference was seen in the prognostic effect of these cell types.While no association was detected between an increasing number of IGF1R+ve CTCs and PFS or OS (p = 0.56 and p = 0.99), the number of IGF1R-ve CTCs ( &lt; 4 vs ≥4) was strongly associated with an increased risk of progression and death: HR 1.93 (95%CI 1.15-3.23, p 0.013) and 3.65 (95%CI 1.88-7.09, p 0.001). In multivariate analysis, adjusted for metformin, the prognostic role of the number of IGF1R-ve CTCs was confirmed, while no residual prognostic role of total CTCs or number of IGF1R+ve cells was found (p = 0.55 and p = 0.64 for PFS; p = 0.86 in both cases for OS). Conclusions: In our study, the loss of IGF1R expression in CTCs exhibited a significant adverse prognostic effect, whereas no significant effect of total CTCs and IGF1R+ve CTCs was observed. This finding supports the biological characterization of CTCs as a critical step for further definition of their prognostic significance.

Purification and Characterization of Schwann Cells from Adult Human Skin and Nerve.

Despite its modest capacity for regeneration, peripheral nervous system injury often results in significant long-term disability. Supplementing peripheral nervous system injury with autologous Schwann cells (SCs) may serve to rejuvenate the postinjury environment to enhance regeneration and ultimately improve functional outcomes. However, human nerve-derived SC (hN-SC) collection procedures require invasive surgical resection. Here, we describe the characterization of SCs from adult human skin (hSk-SCs) of four male donors ranging between 27 and 46 years old. Within five weeks of isolating and culturing adherent mixed skin cells, we were able to obtain 3–5 million purified SCs. We found that hSk-SCs appeared transcriptionally indistinguishable from hN-SCs with both populations exhibiting expression of SC genes including: SOX10, SOX9, AP2A1, CDH19, EGR1, ETV5, PAX3, SOX2, CX32, DHH, NECL4, NFATC4, POU3F1, S100B, and YY1. Phenotypic analysis of hSk-SCs and hN-SCs cultures revealed highly enriched populations of SCs indicated by the high percentage of NES+ve, SOX10+ve, s100+ve and p75+ve cells, as well as the expression of a battery of other SC-associated proteins (PAX3, CDH19, ETV5, SOX2, POU3F1, S100B, EGR2, and YY1). We further show that both hSk-SCs and hN-SCs are capable of promoting axonal growth to similar degrees and that a subset of both associate with regenerating axons and form myelin following transplantation into the injured mouse sciatic nerve. Interestingly, although the majority of both hSk-SCs and hN-SCs maintained SOX10 immunoreactivity following transplant, only a subset of each activated the promyelinating factor, POU3F1, and were able to myelinate. Taken together, we demonstrate that adult hSk-SCs are genetically and phenotypically indistinguishable to hN-SCs.

Trichinella Spiralis Impact on Mesenchymal Stem Cells: Immunohistochemical Study by Image Analyzer in Murine Model

This study aims to elucidate whether Trichinella spiralis infection or its crude antigen administration can stimulate recruitment of CD105+ve/CD45−ve cells that could represent MSCs in intestine and skeletal muscle of experimental BALB/c albino mice compared to healthy control mice. Studied mice were divided into: 20 healthy control, 20 with orally induced T. spiralis infection, 20 received adult worm crude antigen orally and 20 received larval crude antigen intramuscular. According to specific timing schedule, mice were sacrificed and tissue sections were examined for CD105 and CD45 immunohistochemical expression using image J image analyzing software, to compare different study groups. T. spiralis infection induced a significant increase in density of CD105+ve/CD45−ve cells that could represent MSCs in both intestinal and muscle sections, similarly the intramuscular injected larval crude antigen caused more infiltration of such cells in muscles compared to muscle sections from healthy control mice. However, no significant difference was noticed in intestinal sections after oral adult crude antigen administration compared to healthy control mice. So, injected T. spiralis crude antigen might be a successful stimulant to MSCs attraction and recruitment in tissues nearby injection site. This could be beneficial for cell regeneration and tissue repair in case of presence of a disease induced damage.

Platelet-derived growth factor signaling modulates adult hair follicle dermal stem cell maintenance and self-renewal

Hair follicle regeneration is dependent on reciprocal signaling between epithelial cells and underlying mesenchymal cells within the dermal papilla. Hair follicle dermal stem cells reside within the hair follicle mesenchyme, self-renew in vivo, and function to repopulate the dermal papilla and regenerate the connective tissue sheath with each hair cycle. The identity and temporal pattern of signals that regulate hair follicle dermal stem cell function are not known. Here, we show that platelet-derived growth factor signaling is crucial for hair follicle dermal stem cell function and platelet-derived growth factor deficiency results in a progressive depletion of the hair follicle dermal stem cell pool and their progeny. Using αSMACreERT2:RosaYFP:Pdgfrαflox mice, we ablated Pdgfrα specifically within the adult hair follicle dermal stem cell lineage. This led to significant loss of hair follicle dermal stem cell progeny in connective tissue sheath and dermal papilla of individual follicles, and a progressive reduction in total number of anagen hair follicles containing YFP+ve cells. As well, over successive hair cycles, fewer hair follicle dermal stem cells were retained within each telogen hair follicle suggesting an impact on hair follicle dermal stem cell self-renewal. To further assess this, we grew prospectively isolated hair follicle dermal stem cells (Sox2GFP+ve αSMAdsRed+ve) in the presence or absence of platelet-derived growth factor ligands. Platelet-derived growth factor-BB enhanced proliferation, increased the frequency of Sox2+ve hair follicle dermal stem cell progeny and improved inductive capacity of hair follicle dermal stem cells in an ex vivo hair follicle formation assay. Similar effects on proliferation were observed in adult human SKPs. Our findings impart novel insights into the signals that comprise the adult hair follicle dermal stem cell niche and suggest that platelet-derived growth factor signaling promotes self renewal, is essential to maintain the hair follicle dermal stem cell pool and ultimately their regenerative capacity within the hair follicle.

Danazol has potential to cause PKC translocation, cell cycle dysregulation, and apoptosis in breast cancer cells.

Danazol, the established clinical drug, has given promising therapeutic results in a series of clinical trials with breast cancer patients. Danazol shares structural similarities with several known PKC agonists and fits well into the C1 domain. Danazol binds to the C1b domain of PKC with Kd of 5.64±1.27μm. MD simulation studies further support that the PKC-danazol molecular model is stable and showing minimum distortion to the structure during the simulation period. Immunofluorescence and Western blotting studies indicate that MDAMB-231 cells stimulated with danazol exhibit translocation of PKCα to the plasma membrane. Cells stimulated with danazol causes appearance of several phosphorylated proteins in lysate and plasma membrane. In addition, danazol affects carcinogenic molecule (PMA)-induced intracellular signaling in cancer cells. It halted the cancer cells in the G1 phase of the cell cycle and reduced the viability of ER+ve and triple-negative breast cancer cells with an IC50 of 31±2.63 and 65±4.27μg/ml, respectively. DNA fragmentation and flow cytometry experiments revealed that the cell death follows the apoptotic pathway. It affects mitochondrial membrane potentials and releases cytochrome-C from mitochondria to induce downstream apoptosis in breast cancer cells. Hence, the current study may help clinicians to re-design their treatment strategy to optimize therapeutic potentials of the molecule.

Molecular effect of human umbilical cord blood CD34-positive and CD34-negative stem cells and their conjugate in azoospermic mice.

Currently, azoospermia is one of the most common diseases of male infertility. Stem cell research is the new hope for novel therapy with a higher degree of safety and lower cost. This study aimed to investigate the effect of umbilical cord blood-derived stem cells (" and mesenchymal "UCB-MSCs") and mono-cell layer implanted into the induced azoospermic mice testis. Stem cells were isolated from umbilical cord blood and CD34+ve cells were separated from negative one by Mini MACs column. At 5th week after single injection of busulfan, stained mesenchymal (CD34-ve), hematopoietic stem cells (CD34+ve) and their conjugate (mono-cell layer) were injected locally into testis. At the end of the study, MSCs group showed that mRNA levels of genes related to meiosis (Vasa, SCP3, and PgK2) were increased with significant decrease of FSH and LH levels, compared to control group. Histologically, most of the tubules restored normal architecture. In contrast, HSCs and mono-cell layer groups showed statically insignificant change of FSH, LH, and gene expression, compared to control group. Histologically, distorted seminiferous tubules, with reduction in sperm content, and interstitial mononuclear cellular infiltration were seen. There was significant increase in the optical density of PCNA immune reaction in MSCs group than azoospermia, HSCs, and mono-cell layer, while there was non-significant difference between MSCs and control group. The present study suggested that injection of MSCs into chemotherapeutic-induced azoospermia in mice improved testicular failure; histologically and functionally, by restoration of spermatogenic gene expression while HSC and mono-cell layer showed no effect on spermatogenesis added to that mono-cell layer may induce testicular tissue damage.

MAPK pathway control of stem cell proliferation and differentiation in the embryonic pituitary provides insights into the pathogenesis of papillary craniopharyngioma.

Despite the importance of the RAS-RAF-MAPK pathway in normal physiology and disease of numerous organs, its role during pituitary development and tumourigenesis remains largely unknown. Here, we show that the over-activation of the MAPK pathway, through conditional expression of the gain-of-function alleles BrafV600E and KrasG12D in the developing mouse pituitary, results in severe hyperplasia and abnormal morphogenesis of the gland by the end of gestation. Cell-lineage commitment and terminal differentiation are disrupted, leading to a significant reduction in numbers of most of the hormone-producing cells before birth, with the exception of corticotrophs. Of note, Sox2+ stem cells and clonogenic potential are drastically increased in the mutant pituitaries. Finally, we reveal that papillary craniopharyngioma (PCP), a benign human pituitary tumour harbouring BRAF p.V600E also contains Sox2+ cells with sustained proliferative capacity and disrupted pituitary differentiation. Together, our data demonstrate a crucial function of the MAPK pathway in controlling the balance between proliferation and differentiation of Sox2+ cells and suggest that persistent proliferative capacity of Sox2+ cells may underlie the pathogenesis of PCP.

Adult hippocampal neurogenesis is impaired by transient and moderate developmental thyroid hormone disruption

The hippocampus maintains a capacity for neurogenesis throughout life, a capacity that is reduced in models of adult onset hypothyroidism. The effects of developmental thyroid hormone (TH) insufficiency on neurogenesis in the adult hippocampus, however, has not been examined. Graded degrees of TH insufficiency were induced in pregnant rat dams by administration of 0, 3 or 10ppm of 6-propylthiouracil (PTU) in drinking water from gestational day (GD) 6 until weaning. Body, brain, and hippocampal weight were reduced on postnatal day (PN) 14, 21, 78 and hippocampal volume was smaller at the 10 but not 3ppm dose level. A second experiment examined adult hippocampal neurogenesis following developmental or adult onset hypothyroidism. Two male offspring from 0 and 3ppm exposed dams were either maintained on control water or exposed to 3ppm PTU to create 4 distinct treatment conditions (Control-Control; Control-PTU, PTU-Control, PTU-PTU) based on developmental and adult exposures. Beginning on the 28th day of adult exposure to 0 or 3ppm PTU, bromodeoxyuridine (BrdU, 50mg/kg, ip) was administered twice daily for 5days, and one male from each treatment was sacrificed 24h and 28days after the last BrdU dose and brains processed for immunohistochemistry. Although no volume changes were seen in the hippocampus of the neonate at 3ppm, thinning of the granule cell layer emerged in adulthood. Developmental TH insufficiency produced a reduction in newly born cells, reducing BrdU+ve cells at 1 with no further reduction at 28-days post-BrdU. Similar findings were obtained using the proliferative cell marker Ki67. Neuronal differentiations was also altered with fewer doublecortin (Dcx) expressing cells and a higher proportion of immature Dcx phenotypes seen after developmental but not adult TH insufficiency. An impaired capacity for neurogenesis may contribute to impairments in synaptic plasticity and cognitive deficits previously reported by our laboratory and others following moderate degrees of developmental TH insufficiency induced by this PTU model.

Indispensable role of Notch ligand-dependent signaling in the proliferation and stem cell niche maintenance of APC-deficient intestinal tumors

Ligand-dependent activation of Notch signaling is required to maintain the stem-cell niche of normal intestinal epithelium. However, the precise role of Notch signaling in the maintenance of the intestinal tumor stem cell niche and the importance of the RBPJ-independent non-canonical pathway in intestinal tumors remains unknown. Here we show that Notch signaling was activated in LGR5+ve cells of APC-deficient mice intestinal tumors. Accordingly, Notch ligands, including Jag1, Dll1, and Dll4, were expressed in these tumors. In vitro studies using tumor-derived organoids confirmed the intrinsic Notch activity-dependent growth of tumor cells. Surprisingly, the targeted deletion of Jag1 but not RBPJ in LGR5+ve tumor-initiating cells resulted in the silencing of Hes1 expression, disruption of the tumor stem cell niche, and dramatic reduction in the proliferation activity of APC-deficient intestinal tumors in vivo. Thus, our results highlight the importance of ligand-dependent non-canonical Notch signaling in the proliferation and maintenance of the tumor stem cell niche in APC-deficient intestinal adenomas.

Construction and Testing of Two Distinct Humanized CD19-Specific Chimeric Antigen Receptors (CARs) for the Treatment of B-Cell Malignancies

Introduction: Modificiation of T cells using CD19-specific chimeric antigen receptor (CAR) therapy has produced dramatic responses against a number of hematologic malignancies in multiple clinical trials. To date, most of the CARs studied in clinical trials are derived from mouse single chain fragment variable (scFv), which can elicit an immune response when infused into human patients and thereby can limit the persistency of CAR-T cells. Indeed, a subset of patients with limited persistency of infused CAR-Ts has been observed in clinical trials. However, this can be overcome by utilizing the humanized scFv in CAR design. Here, we constructed two new CD19-specific CARs, which are derived from the scFv of two distinct humanized CD19 antibody clones and compared them with the widely used CD19-CAR derived from a mouse scFv (FMC63).Methods: Lentiviral constructs encoding FMC63-BBZ CAR was generated based on the published sequence of FMC63 scFV and cloned in to a lentiviral vector driven by an EF1α promoter. The FMC63-BBZ CAR sequence was fused in frame with T2A ribosomal skip sequence followed by a puromycin resistance gene (PAC). Humanized CD19-Specific CARs were generated by replacing the FMC63 sequence with two humanized CD19-specific scFv sequences that were derived from two distinct humanized monoclonal antibodies. 293FT cells were used to make lentiviruses and the concentrated viruses were used to infect T-cells from healthy donors, NK92MI and Jurkat-NFAT-GFP (JNG) cells. Surface expressions of CARs were detected by protein-L staining using flow cytometry. Cytolytic activity of CAR-engineered T and NK cells was measured using a 4 hour co-culture assay. Cytokines (IL-2, IFN-γ and TNF-α) were measured from the co-cultured supernatants by ELISA.Results: We were able to infect primary-T cells, NK92MI and JNG cells using the FMC63 and humanized CAR constructs, and the surface expression of CARs was comparable between them. Co-culture of JNG cells stably expressing the FMC63 or humanized CARs with CD19+ve Raji (Burkitt Lymphoma), Nalm6 (Pre- B-cell acute lymphoblastic leukemia) and BV173 (Chronic Myeloid Leukemia) cancer cells lead to robust expression of GFP (indicative of activated NFAT signaling), CD69 (an activation marker for cytotoxic cells), and a rapid increase in the secretion of IL-2. None of these effects were observed in unmodified JNG cells or with the co-culture of JNG cells stably expressing FMC63 or humanized CARs with CD19-ve HL60 (Acute Promyelocytic Leukemia) and U937 (Histiocytic Lymphoma) cancer cells. Next, we made stable NK92MI cells expressing FMC63, humanized CD19-specific CARs, and a control CAR, followed by cellular cytotoxicity assay. Both FMC63-CAR and humanized CD19-CARs expressing NK92MI cells readily eliminated CD19+ve cancer cells, whereas they had no discernible effect on CD19-ve cancer cells. Furthermore, parental or a control CAR expressing NK92MI cells are without any effect, either with CD19+ve or CD19-ve cancer cells, thereby strictly highlighting the comparable specificity of our humanized CD19-CARs with FMC63-CAR against CD19+ve cells. More importantly, co-culture of NK92MI cells stably expressing FMC63-CAR and humanized CD19-CARs with direct patient samples [CD19+ve B-ALLs and CD19-ve Acute Myelogenous Leukemia’s (AMLs)] eliminated only the patient B-ALLs, but without any effect on patient AMLs. Also, increased surface expression of CD69 and robust secretion of cytokines (IFN-γ and TNF-α) were observed only when FMC63 or humanized CD19-CARs expressing NK92MI cells were incubated with CD19+ve patient B-ALLs. Finally, expression of FMC63and humanized CD19-CARs in primary donor T-cells also resulted in the elimination CD19+ve cancer cells along with a significant increase in the secretion of cytokines. Most importantly, both humanized CD19-specific CARs significantly increased the survival of CD19+ve cancer cells bearing NSG mice, whereas the unmodified T-cells or the T-cells expressing a non-specific CAR were without any effect.Conclusion: Our extensive pre-clinical study clearly shows that humanized CD19-specific CAR-T or NK cells exhibit comparable potency with the widely used FMC63-CAR, which provides the basis for the clinical testing of these humanized CARs in CD19+ve malignancies, thereby allaying the possible concern on immune mediated rejection of mouse scFv based CD19-CAR therapy. DisclosuresNo relevant conflicts of interest to declare.

The Mitochondrial Carrier Homolog 2 (MTCH2) Regulates the Differentiation of AML Cells By Influencing the Localization of Pyruvate Dehydrogenase Complex and H3 and H4 Histone Acetylation

Mitochondrial carrier homolog 2 (MTCH2) is a mitochondrial outer membrane protein that functions as a receptor-like protein for pro-apoptotic BID. In addition to its role in apoptosis, recent findings show that MTCH2 also regulates cellular metabolism. In murine hematopoietic cells, loss of MTCH2 increases oxidative phosphorylation and reduces the number of hematopoietic stem cells.Here, we sought to understand the role of MTCH2 in leukemogenesis and knocked down MTCH2 in leukemia cell lines using multiple independent shRNAs. Knockdown of MTCH2 reduced growth and viability of AML cells: OCI-AML2 (>90%), TEX (>80%), U937 (>65%), and HL60 (>75%). MTCH2 knockdown also decreased the clonogenic growth of OCI-AML2 (>60%), TEX (>70%), and U937 (>40%) cells compared to controls. However, MTCH2 knockdown did not induce cell death as indicated by annexin V/PI staining. In addition, knockdown of MTCH2 in TEX cells reduced engraftment into the marrow of non-obese diabetic/severe combined immunodeficiency-growth factor (NOD/SCID-GF) mice (control 17±4%, n=10) vs. sh-MTCH2 (4±0.86%, n=10). In mouse models, knockout of MTCH2 decreased the leukomogenic potential of murine hematopoietic stem cells transformed with the MLL-AF9 oncogene and increased the survival of these mice.To understand the mechanism by which MTCH2 knockdown decreased cell growth, we used genome wide transcriptome analysis with RNA-seq and observed an up regulation of genes involved in cellular differentiation. Consistent with increased MTCH2 knockdown promoting differentiation, OCI-AML2 cells with MTCH2 knockdown displayed increased non-specific esterase staining. Increased differentiation (Lin+ve cells) was also observed in MLL-AF9 with MTCH2 knockout. Knockdown of MTCH2 in TEX and OCI-AML2 cells increased levels of H3 and H4 histone acetylation as demonstrated by immunoblotting. Of note, differentiation and increased H3 and H4 acetylation was not observed after inhibiting other mitochondrial processes, such as mitochondrial protein synthesis or mitochondrial DNA replication. Although MTCH2 is a receptor for BID, the increased H3 and H4 acetylation appeared independent of BID as small molecule BID inhibitors did not alter H3 and H4 acetylation.MTCH2 regulates cell metabolism. Therefore, we measured changes in intracellular metabolites in AML cells after MTCH2 knockdown. In AML cells, MTCH2 knockdown increased levels of lactate (2 fold), but did not change the basal rate of oxygen consumption or the activity of mitochondrial respiratory chain complexes.Loss of mitochondrial pyruvate dehydrogenase complex increases lactate levels and a recent study reported that the translocation of pyruvate dehydrogenase complex from the mitochondria to the nucleus under conditions of mitochondrial stress, increases H3 and H4 histone acetylation (Cell. 2014; 158(1):84-97). Therefore, we measured changes in the localization of pyruvate dehydrogenase complex after MTCH2 knockdown. Knockdown of MTCH2 decreased mitochondrial and increased nuclear dehydrogenase complex in OCI-AML2 and TEX cells.Thus, in summary, MTCH2 regulates the differentiation of AML cells and controls the localization of pyruvate dehydrogenase complex and histone acetylation. These results also suggest a mechanism by which loss of MTCH2 leads to reductions of normal hematopoietic stem cells. DisclosuresSchimmer:Novartis: Honoraria.