Mesenchymal stromal cells and their small extracellular vesicles in allergic diseases: From immunomodulation to therapy.

Mesenchymal stromal cells (MSCs) have long been considered a potential tool for treatment of allergic inflammatory diseases, owing to their immunomodulatory characteristics. In recent decades, the medical utility of MSCs has been evaluated both in vitro and in vivo, providing a foundation for therapeutic applications. However, the existing limitations of MSC therapy indicate the necessity for novel therapies. Notably, small extracellular vesicles (sEV) derived from MSCs have emerged rapidly as candidates instead of their parental cells. The acquisition of abundant and scalable MSC-sEV is an obstacle for clinical applications. The potential application of MSC-sEV in allergic diseases has attracted increasing attention from researchers. By carrying biological microRNAs or active proteins, MSC-sEV can modulate the function of various innate and adaptive immune cells. In this review, we summarise the recent advances in the immunomodulatory properties of MSCs in allergic diseases, the cellular sources of MSC-sEV, and the methods for obtaining high-quality human MSC-sEV. In addition, we discuss the immunoregulatory capacity of MSCs and MSC-sEV for the treatment of asthma, atopic dermatitis, and allergic rhinitis, with a special emphasis on their immunoregulatory effects and the underlying mechanisms of immune cell modulation.

Mesenchymal stromal cells-derived small extracellular vesicles modulate DC function to suppress Th2 responses via IL-10 in patients with allergic rhinitis.

Mesenchymal stromal cells (MSCs) are well known for their immunoregulatory roles on allergic inflammation particularly by acting on T cells, B cells, and dendritic cells (DCs). MSC-derived small extracellular vesicles (MSC-sEV) are increasingly considered as one of the main factors for the effects of MSCs on immune responses. However, the effects of MSC-sEV on DCs in allergic diseases remain unclear. MSC-sEV were prepared from the induced pluripotent stem cells (iPSC)-MSCs by anion-exchange chromatography, and were characterized with the size, morphology, and specific markers. Human monocyte-derived DCs were generated and cultured in the presence of MSC-sEV to differentiate the so-called sEV-immature DCs (sEV-iDCs) and sEV-mature DCs (sEV-mDCs), respectively. The phenotypes and the phagocytic ability of sEV-iDCs were analyzed by flow cytometry. sEV-mDCs were co-cultured with isolated CD4+ T cells or peripheral blood mononuclear cells (PBMCs) from patients with allergic rhinitis. The levels of Th1 and Th2 cytokines produced by T cells were examined by ELISA and intracellular flow staining. And the following mechanisms were further investigated. We demonstrated that MSC-sEV inhibited the differentiation of human monocytes to iDCs with downregulation of the expression of CD40, CD80, CD86, and HLA-DR, but had no effects on mDCs with these markers. However, MSC-sEV treatment enhanced the phagocytic ability of mDCs. More importantly, using anti-IL-10 monoclonal antibody or IL-10Rα blocking antibody, we identified that sEV-mDCs suppressed the Th2 immune response by reducing the production of IL-4, IL-9, and IL-13 via IL-10. Furthermore, sEV-mDCs increased the level of Treg cells. Our study identified that mDCs treated with MSC-sEV inhibited the Th2 responses, providing novel evidence of the potential cell-free therapy acting on DCs in allergic airway diseases.

[Bladder wall neourethra technique improves early urinary continence after laparoscopic radical prostatectomy].

OBJECTIVE: To study the effect of the bladder wall neourethra (BWN) technique on early urinary continence after laparoscopic radical prostatectomy (LRP). METHODS: We prospectively selected 40 cases of LRP performed in our hospital from August 2020 to August 2021 and randomly divided them into a BWN group (n = 20) and a control group (n = 20). We recorded the urinary continence rate of the two groups of patients at 7, 30, 90 and 180 days, and measured the maximum urethral pressure (MUP), functional urethral length (FUL) and functional urethral area (UFA) and observed the shape of the neourethra closure by MRI at 1 month after catheter removal. RESULTS: The urinary continence rates were significantly higher in the BWN than in the control group at 7 days (90.0% vs 25.0%, P < 0.001), 30 days (95.0% vs 35.0%, P < 0.001), 90 days (100% vs 60.0%, P < 0.05) and 180 days (100% vs 90.0%, P > 0.05) after catheter removal. No statistically significant difference was observed in MUP between the two groups (P > 0.05). FUL and FUA were remarkably higher in the BWN than in the control group (P < 0.01). MRI showed tight closure of the neourethra in the BWN group in the urine storage period. CONCLUSION: The BWN technique can significantly prolong FUL and improve early urinary continence after LRP.

IL-33 receptor expression on myeloid and plasmacytoid dendritic cells after allergen challenge in patients with allergic rhinitis.

The diversity of immune responses in allergic diseases is critically mediated by dendritic cells (DCs), including myeloid and plasmacytoid DCs. Allergen inhalation increased the release of IL-33 from patients with allergic rhinitis (AR), which affecting the downstream cells by binding to its receptor (ST2). However, the effects of inhaled allergens on the expression of ST2 by DCs and IL-33 on the function of mDCs are unknown. The levels of ST2+mDCs and ST2+pDCs in the blood from patients with AR and healthy subjects were examined using flow cytometry. Moreover, the patients were challenged using the allergens and the levels of ST2+mDCs and ST2+pDCs were investigated at different time points. We found that there were higher levels of ST2+ mDCs and ST2+ pDCs in patients with AR, and these levels were further increased 0.5 h after allergen inhalation. Additionally, the type 2 immune response was upregulated after challenge. IL-33 treatment increased the expression of ST2 on mDCs. Our study demonstrated that ST2 was upregulated on DCs after allergen inhalation and that mDCs responded directly to IL-33 through ST2, suggesting that the IL-33/ST2 axis might play an important role in the pathogenesis of allergic rhinitis by DCs.

[Case control study on T-plate combined with suture anchors for the treatment of Neer â ¡b clavicle fractures].

OBJECTIVE: To compare the clinical efficacy of distal radius T-plate combined with suture anchor and distal clavicle anatomical locking plate combined with suture anchor in the treatment of Neer Ⅱb distal clavicle fracture. METHODS: From June 2014 to June 2018, 42 patients with Neer Ⅱb distal clavicle fractures were retrospectively analyzed. According to different surgical methods, they were divided into the observation group (T-shaped plate combined with suture anchor) and the control group (anatomical locking plate combined with suture anchor). There were 22 patients in the observation group and 20 patients in the control group. In the observation group, there were 13 males and 9 females, aged from 22 to 70 (45.78± 14.44) years old, 12 cases on the left side and 10 cases on the right side, 8 cases of traffic accident injury and 14 cases of fall. In the control group, there were 12 males and 8 females, aged from 24 to 66 (44.17±15.58) years, 13 cases on the left side and 7 cases on the right side, 6 cases of traffic accident injuryand 14 cases of fall. The operation time, intraoperative blood loss and fracture healing time were compared between the two groups, and Constant Murley score was used to evaluate shoulder joint function. RESULTS: The patients in both groups were followed up for 18 to 24 (20.96±2.02) months. The incisions of both groups were healed at stageⅠ. The fracture ends of both groups were bony healed at the last follow up. There was no significant difference in operation time, intraoperative blood loss and fracture healing time between two groups (P>0.05);there was no significant difference in shoulder joint function between two groups at 3 months after operation (P>0.05). CONCLUSION: The two methods can obtain satisfactory results in the treatment of Neer Ⅱb distal clavicle fractures, especially suitable for patients with comminuted distal clavicle fractures or osteoporosis; the clinical effect of the treatment of NeerⅡb distal clavicle fractures with T type distal radius plate combined with suture anchor is satisfactory, which provides another feasible treatment scheme for clinic.

Mesenchymal stem cells regulate type 2 innate lymphoid cells via regulatory T cells through ICOS-ICOSL interaction.

Group 2 innate lymphoid cells (ILC2s) are recognized as key controllers and effectors of type 2 inflammation. Mesenchymal stem cells (MSCs) have been shown to alleviate type 2 inflammation by modulating T lymphocyte subsets and decreasing TH 2 cytokine levels. However, the effects of MSCs on ILC2s have not been investigated. In this study, we investigated the potential immunomodulatory effects of MSCs on ILC2s in peripheral blood mononuclear cells (PBMCs) from allergic rhinitis patients and healthy subjects. We further investigated the mechanisms involved in the MSC modulation using isolated lineage negative (Lin- ) cells. PBMCs and Lin- cells were cocultured with induced pluripotent stem cell-derived MSCs (iPSC-MSCs) under the stimulation of epithelial cytokines IL-25 and IL-33. And the ILC2 levels and functions were examined and the possible mechanisms were investigated based on regulatory T (Treg) cells and ICOS-ICOSL pathway. iPSC-MSCs successfully decreased the high levels of IL-13, IL-9, and IL-5 in PBMCs in response to IL-25, IL-33, and the high percentages of IL-13+ ILC2s and IL-9+ ILC2s in response to epithelial cytokines were significantly reversed after the treatment of iPSC-MSCs. However, iPSC-MSCs were found directly to enhance ILC2 levels and functions via ICOS-ICOSL interaction in Lin- cells and pure ILC2s. iPSC-MSCs exerted their inhibitory effects on ILC2s via activating Treg cells through ICOS-ICOSL interaction. The MSC-induced Treg cells then suppressed ILC2s by secreting IL-10 in the coculture system. This study revealed that human MSCs suppressed ILC2s via Treg cells through ICOS-ICOSL interaction, which provides further insight to regulate ILC2s in inflammatory disorders.

Sex differences in group 2 innate lymphoid cell-dominant allergic airway inflammation.

There were gender differences in the prevalence and severity of allergic diseases. Group 2 innate lymphoid cells (ILC2s) were recently reported to play a critical role in allergic diseases. We investigated the sex-dependent differences in ILC2-dominant allergic airway inflammation model using T\B cell-deficient mice, and determined the gender differences of ILC2 levels in patients with asthma and allergic rhinitis. Female mice exhibited higher levels of inflammatory infiltration and large production of IL-5 and IL-13, especially for ILC2 levels compared to male mice with the induction of IL-33. However, no significant differences were found for the levels of circulating ILC2s between the genders of patients. The treatment of testosterone significantly decreased the intracellular type 2 cytokines in ILC2s and the proliferation of pure ILC2s in response to epithelial cytokines. Our study suggested the sex differences and the involvement of androgen on ILC2s in allergic diseases.

Small extracellular vesicles derived from human MSCs prevent allergic airway inflammation via immunomodulation on pulmonary macrophages.

Allergic airway inflammation is a major public health disease that affects up to 300 million people in the world. However, its management remains largely unsatisfactory. The dysfunction of pulmonary macrophages contributes greatly to the development of allergic airway inflammation. It has been reported that small extracellular vesicles derived from mesenchymal stromal cells (MSC-sEV) were able to display extensive therapeutic effects in some immune diseases. This study aimed to investigate the effects of MSC-sEV on allergic airway inflammation, and the role of macrophages involved in it. We successfully isolated MSC-sEV by using anion exchange chromatography, which were morphologically intact and positive for the specific EV markers. MSC-sEV significantly reduced infiltration of inflammatory cells and number of epithelial goblet cells in lung tissues of mice with allergic airway inflammation. Levels of inflammatory cells and cytokines in bronchoalveolar lavage fluid were also significantly decreased. Importantly, levels of monocytes-derived alveolar macrophages and M2 macrophages were significantly reduced by MSC-sEV. MSC-sEV were excreted through spleen and liver at 24 h post-administration in mice, and were able to be taken in by macrophages both in vivo and in vitro. In addition, proteomics analysis of MSC-sEV revealed that the indicated three types of MSC-sEV contained different quantities of proteins and shared 312 common proteins, which may be involved in the therapeutic effects of MSC-sEV. In total, our study demonstrated that MSC-sEV isolated by anion exchange chromatography were able to ameliorate Th2-dominant allergic airway inflammation through immunoregulation on pulmonary macrophages, suggesting that MSC-sEV were promising alternative therapy for allergic airway inflammation in the future.

Small extracellular vesicles derived from human mesenchymal stromal cells prevent group 2 innate lymphoid cell-dominant allergic airway inflammation through delivery of miR-146a-5p.

Group 2 innate lymphoid cells (ILC2s) are recently reported to play a more critical role in allergic diseases. We previously identified that mesenchymal stromal cells (MSCs) elicited therapeutic effects on allergic airway inflammation. Small extracellular vesicles (sEV) derived from MSCs possess striking advantages including low immunogenicity and high biosafety, and is extremely promising cell-free therapeutic agents. However, the effects of MSC-sEV on ILC2s are still unclear. Additionally, scalable isolation protocols are required for the mass production of homogenous MSC-sEV especially in clinical application. We previously reported that induced pluripotent stem cells-derived MSCs were the ideal cellular source for the large preparation of MSC-sEV. Here we developed a standardized scalable protocol of anion-exchange chromatography for isolation of MSC-sEV, and investigated the effects of MSC-sEV on ILC2 function from patients with allergic rhinitis and in a mouse ILC2-dominant asthma model. The characterization of MSC-sEV was successfully demonstrated in terms of size, morphology and specific markers. Using flow cytometry and human Cytokine Antibody Array, MSC-sEV but not fibroblasts-sEV (Fb-sEV) were found to significantly inhibit the function of human ILC2s. Similarly, systemic administration of MSC-sEV but not Fb-sEV exhibited an inhibition of ILC2 levels, inflammatory cell infiltration and mucus production in the lung, a reduction in levels of T helper 2 cytokines, and alleviation of airway hyperresponsiveness in a mouse model of asthma. Using RNA sequencing, miR-146a-5p was selected as the candidate to mediate the above effects of MSC-sEV. We next revealed the uptake of ILC2s to MSC-sEV, and that transfer of miR-146a-5p in MSC-sEV to ILC2s in part contributed to the effects of MSC-sEV on ILC2s in vitro and in a mouse model. In conclusion, we demonstrated that MSC-sEV were able to prevent ILC2-dominant allergic airway inflammation at least partially through miR-146a-5p, suggesting that MSC-sEV could be a novel cell-free strategy for the treatment of allergic diseases.

Effects of myeloid and plasmacytoid dendritic cells on ILC2s in patients with allergic rhinitis.

BACKGROUND: Group 2 innate lymphoid cells (ILC2s) were reported to serve a critical role in allergic diseases. Myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) play significant roles in allergic immune response. However, effects of DCs on ILC2s in allergic diseases, especially for patients with allergic rhinitis (AR), remain unclear. OBJECTIVE: We sought to address the roles of mDCs and pDCs in regulating ILC2 function in AR. METHODS: mDCs and pDCs were cocultured with human PBMCs isolated from patients with AR or ILC2s to measure soluble or intracellular TH2 cytokines, transcription factors, signaling pathways in ILC2s, and the following mechanisms were further investigated. The levels of peripheral IL-33+mDCs, pDCs, and ILC2s were studied in patients under an inhaled allergen challenge. RESULTS: We confirmed the presence of ILC2s, mDCs, and pDCs in the nasal mucosa of patients with AR. Both allogenic and autologous mDCs were found to activate ILC2s from patients with AR to produce TH2 cytokines, and increase the levels of GATA-3 and signal transducer and activator of transcription signaling pathways, in which IL-33-producing mDCs exerted the major role by binding on ST2 on ILC2s. We further identified high levels of IL-33+mDCs and ILC2s in patients with AR under antigen challenge. Activated pDCs inhibited the cytokine production of ILC2s isolated from patients with AR by secretion of IL-6. CONCLUSIONS: mDCs promote ILC2 function by the IL-33/ST2 pathway, and activation of pDCs suppresses ILC2 function through IL-6 in patients with AR. Our findings provide new understanding of the interplay between DCs and ILC2s in allergic diseases.

Association between methylation of DNA damage response-related genes and DNA damage in hepatocytes of rats following subchronic exposure to vinyl chloride.

In the present study, we investigated the association between methylation of DNA damage response-related genes such as cyclin-dependent kinase inhibitor (CDKN)2A, Ras association (RalGDS/AF-6) domain family member (RASSF)1A, O6-methylguanine DNA methyltransferase (MGMT), Kirsten rat sarcoma viral oncogene homolog (KRAS), and spleen-associated tyrosine kinase (SYK) and DNA damage in hepatocytes of rats following subchronic exposure to vinyl chloride (VC). Sixty-four healthy rats were randomly divided into three VC exposure groups (5, 25, and 125 mg/kg) and an untreated negative control group (n = 16 each). VC was administered by intraperitoneal injection every other day for a total of three times a week. Eight randomly selected rats from each group were sacrificed at the end of 6 and 12 weeks, and liver tissue was harvested for the comet assay and for assessment of DNA methylation level and mRNA expression of related genes by PCR. Overall methylation levels in the genome of hepatocytes in VC-exposed rats were higher than those in the control group at 6 and 12 weeks (P < 0.05), although no differences were observed with regarding to dose (P > 0.05). After 12 weeks of exposure, differences in the methylation of RASSF1A and MGMT promoter regions were observed between the high-dose group and other groups (P < 0.05), whereas no differences were observed for the KRAS, SYK, and CDKN2A promoters (P > 0.05). These results suggest that DNA damage and increased genome-wide methylation are biomarkers for VC exposure and that RASSF1A and MGMT promoter methylation is related to the carcinogenic mechanism of VC.

Pedobacter chitinilyticus sp. nov., a chitin-degrading bacterium isolated from wheat leaf tissue.

A bacterium, designated strain CM134L-2T, was isolated from a chitin-enriched wheat leaf microbiome in Chengdu, Sichuan province, China. It was Gram-stain-negative, strictly aerobic, non-spore-forming, motile, rod-shaped, and bright yellow in colour. Strain CM134L-2T grew at 4-35 °C, at pH 6.0-9.0 and could use chitin as the only carbon resource. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CM134L-2T was most closely related to Pedobacter nanyangensis Q-4T (97.7 %) and Pedobacter zeaxanthinifaciens TDMA-5T (97.4 %). Digital DNA-DNA hybridization (dDDH) values between strain CM134L-2T with these two type strains were 26.8  and 20.8 %, respectively, and average nucleotide identity (ANI) values were 83.2 and 76.2 %; these values are lower than the proposed and generally accepted species boundaries of 70 % for dDDH and 95-96 % for ANI, which suggests strain CM134L-2T represents a novel species. The genomic DNA G+C content of strain CM134L-2T was 39.3 mol%, menaquinone-7 was the major respiratory quinone, phosphatidylethanolamine was the major polar lipid and the major components of the cellular fatty acids were iso-C15 : 0, and C16 : 1ω7c/C16 : 1ω6c (summed feature 3); these features supported the affiliation of strain CM134L-2T to the genus Pedobacter. Overall, strain CM134L-2T belongs to the genus Pedobacter, but can be classified as a novel species, for which the name Pedobacter chitinilyticus sp. nov. is proposed. The type strain is CM134L-2T (=CGMCC 1.16520T=KCTC 62643T).

Connexin 43-Mediated Mitochondrial Transfer of iPSC-MSCs Alleviates Asthma Inflammation.

We previously identified an immunomodulatory role of human induced pluripotent stem cell (iPSC)-derived mesenchymal stem cells (MSCs) in asthmatic inflammation. Mitochondrial transfer from bone marrow MSCs to epithelial cells can result in the attenuation of acute lung injury in mice. However, the effects of mitochondrial transfer from iPSC-MSCs to epithelial cells in asthma and the mechanisms underlying these effects are unclear. We found that iPSC-MSC transplantation significantly reduced T helper 2 cytokines, attenuated the mitochondrial dysfunction of epithelial cells, and alleviated asthma inflammation in mice. Tunneling nanotubes (TNTs) were formed between iPSC-MSCs and epithelial cells, and mitochondrial transfer from iPSC-MSCs to epithelial cells via TNTs was observed both in vitro and in mice. Overexpression or silencing of connexin 43 (CX43) in iPSC-MSCs demonstrated that CX43 plays a critical role in the regulation of TNT formation by mediating mitochondrial transfer between iPSC-MSCs and epithelial cells. This study provides a therapeutic strategy for targeting asthma inflammation.

Induced pluripotent stem cell-derived mesenchymal stem cells activate quiescent T cells and elevate regulatory T cell response via NF-κB in allergic rhinitis patients.

BACKGROUND: It has been demonstrated previously that induced pluripotent stem cell (iPSC)-derived mesenchymal stem cells (MSCs) have immunosuppressive effects on activated T cells. However, the effects of iPSC-MSCs on quiescent T cells are still unknown. The aim of this study was to identify the immunomodulatory role of iPSC-MSCs on resting peripheral blood mononuclear cells (PBMCs) from allergic rhinitis (AR) patients. METHODS: PBMCs were cocultured with iPSC-MSCs without any stimulation, following which lymphocyte proliferation, activation of T cells, TH1/TH2 and regulatory T (Treg) cell differentiation, and Treg cell function were analyzed. The roles of soluble factors and cell-cell contact were examined to investigate the mechanisms involved. RESULTS: iPSC-MSCs promoted the proliferation of resting lymphocytes, activated CD4+ and CD8+ T cells, and upregulated and activated Treg cells without any additional stimulation. In addition, iPSC-MSCs balanced biased TH1/TH2 cytokine levels. Cell-cell contact was confirmed to be a possible mechanism involved. NF-κB was identified to play an important role in the immunomodulatory effects of iPSC-MSCs on quiescent T cells. CONCLUSIONS: iPSC-MSCs activate quiescent T cells and elevate regulatory T-cell response in AR patients, suggesting different immunomodulatory functions of iPSC-MSCs according to the phases of diseases. Therefore, iPSC-MSCs are a potential therapeutic candidate for treating allergic airway inflammation.

MicroRNA-21 Mediates the Protective Effects of Mesenchymal Stem Cells Derived from iPSCs to Human Bronchial Epithelial Cell Injury Under Hypoxia.

Airway epithelial cell injury is a key triggering event to activate allergic airway inflammation, such as asthma. We previously reported that administration of mesenchymal stem cells (MSCs) significantly alleviated allergic inflammation in a mouse model of asthma, and the mmu-miR-21/ACVR2A axis may be involved. However, whether MSCs protect against bronchial epithelial cell injury induced by hypoxia, and the underlying mechanism, remain unknown. In our study, the human bronchial epithelial cell line BEAS-2B was induced to undergo apoptosis with a hypoxia mimic of cobalt chloride (CoCl2) damage. Treatment of MSCs derived from induced pluripotent stem cells (iPSCs) significantly decreased apoptosis of BEAS-2B cells. There was high miR-21 expression in injured BEAS-2B cells after MSC treatment. Transfection of the miR-21 mimic significantly decreased apoptosis of BEAS-2B, and transfection of a miR-21 inhibitor significantly increased apoptosis. More importantly, the protective effects of MSCs on injured BEAS-2B were reversed by transfection of the miR-21 inhibitor. Binding sites of human miR-21 were identified in the 3'UTR of human ACVR2A. We further determined that CoCl2 stimulation increased ACVR2A expression at both the mRNA and protein levels. Moreover, transfection of the miR-21 mimic further up-regulated ACVR2A expression induced by CoCl2, whereas transfection of the miR-21 inhibitor down-regulated ACVR2A expression. In addition, MSCs increased ACVR2A expression in BEAS-2B cells; however, this effect was reversed after transfection of the miR-21 inhibitor. Our data suggested that MSCs protect bronchial epithelial cells from hypoxic injury via miR-21, which may represent an important target. These findings suggest the potentially wide application of MSCs for epithelial cell injury during hypoxia.

Rb deficiency accelerates progression of carcinoma of the urinary bladder in vivo and in vitro through inhibiting autophagy and apoptosis.

Urinary bladder cancer is known as a common cancer diagnosed across the world and results in significant mortality and morbidity rates among patients. The retinoblastoma (Rb) protein, as a main tumor suppressor, controls cellular responses to potentially oncogenic stimulation. Rb phosphorylation could disrupt E2F complex formation, resulting in diverse transcription factor dysfunction. In our study, we investigated how Rb is involved in controlling urinary bladder cancer progression. The results indicate that Rb expression is reduced in mice with urinary bladder tumor, and its suppression leads to urinary bladder cancer progression in vivo and in vitro. Rb mutation directly results in tumor size with lower survival rate in vivo. Rb knockdown in vitro promoted bladder tumor cell proliferation, migration and invasion. Interestingly, Rb knockout and knockdown result in autophagy and apoptosis inhibition via suppressing p53 and caspase-3 signaling pathways, enhancing bladder cancer development in vitro and in vivo. These findings reveal that Rb deficiency accelerated urinary bladder cancer progression, exposing an important role of Rb in suppressing urinary bladder cancer for treatment in the future.

Actein induces autophagy and apoptosis in human bladder cancer by potentiating ROS/JNK and inhibiting AKT pathways.

Human bladder cancer is a common genitourinary malignant cancer worldwide. However, new therapeutic strategies are required to overcome its stagnated survival rate. Triterpene glycoside Actein (ACT), extracted from the herb black cohosh, suppresses the growth of human breast cancer cells. Our study attempted to explore the role of ACT in human bladder cancer cell growth and to reveal the underlying molecular mechanisms. We found that ACT significantly impeded the bladder cancer cell proliferation via induction of G2/M cycle arrest. Additionally, ACT administration triggered autophagy and apoptosis in bladder cancer cells, proved by the autophagosome formation, LC3B-II accumulation, improved cleavage of Caspases/poly (ADP-ribose) polymerase (PARP). Furthermore, reduction of reactive oxygen species (ROS) and p-c-Jun N-terminal kinase (JNK) could markedly reverse ACT-induced autophagy and apoptosis. In contrast, AKT and mammalian target of rapamycin (mTOR) were greatly de-phosphorylated by ACT, while suppressing AKT and mTOR activity could enhance the effects of ACT on apoptosis and autophagy induction. In vivo, ACT reduced the tumor growth with little toxicity. Taken together, our findings indicated that ACT suppressed cell proliferation, induced autophagy and apoptosis through promoting ROS/JNK activation, and blunting AKT pathway in human bladder cancer, which indicated that ACT might be an effective candidate against human bladder cancer in future.

Rb knockdown accelerates bladder cancer progression through E2F3 activation.

Bladder cancer is one of the most common cancers diagnosed in the world and leads to significant mortality and morbidity among affected patients. The retinoblastoma (Rb) protein is a main tumor suppressor, controlling cellular responses to potentially oncogenic stimulation. E2F3 was invariably disrupted in different human cancers for its central role in the control of cellular proliferation. Here, we investigated how Rb is integrated to control bladder cancer progression through E2F3 and p53 regulation. The results exhibit that Rb expression is lower in patients with bladder tumor, while E2F3 level is high. Rb knockdown enhanced bladder tumor cell proliferation and migration, aggravated with p53 silence. Interestingly, Rb silence results in E2F3, Myc and mTOR signaling pathway activation, contributing to bladder cancer cell proliferation and apoptosis suppression mainly through caspase-3 inhibition in vitro and in vivo. Immunohistochemical analysis revealed that Rb is highly expressed in normal bladder cells, but was repressed in tumor tissues of the bladder completely, suggesting a possible role of Rb as a tumor suppressor.

MicroRNAs Involved in Asthma After Mesenchymal Stem Cells Treatment.

Administration of human bone marrow-derived mesenchymal stem cells (BM-MSCs) significantly alleviates allergic airway inflammation. There are no studies that refer to the role of microRNAs (miRNAs) after the BM-MSCs treatment in airway allergic inflammation. We induced a mouse model of asthma and performed the transplantation of BM-MSCs. We analyzed aberrant miRNAs and key immune regulators using both miRNA and messenger RNA (mRNA) polymerase chain reaction (PCR) arrays. We identified that 296 miRNAs were differently expressed after the induction of asthma and/or the treatment of BM-MSCs, in which 14 miRNAs presented the reverse variation tendency between asthma induction and BM-MSCs transplantation. Mmu-miR-21a-3p, mmu-miR-449c-5p, and mmu-miR-496a-3p were further confirmed to be differently expressed with additional samples and quantitative real-time PCR. With an mRNA PCR array, we identified 19 genes to be involved in the allergy induction and the administration of BM-MSCs. Further target genes analysis revealed that mmu-miR-21a-3p was significantly correlated with the immune regulator activin A receptor, Type IIA (Acvr2a). Mmu-miR-21a-3p had opposite expression with Acvr2a after asthma and BM-MSCs treatment. Acvr2a had binding sites for miR-21a for both mice and human, suggesting that miR-21/Acvr2a axis is conserved between human and mice. Dual-luciferase reporter assay showed that mmu-miR-21a-3p negatively regulated the transcript of Acvr2a. In addition, has-miR-21a inhibitor significantly increased the expression of Acvr2a mRNA in BEAS-2B cells under lipopolysaccharide stimulation. Our results suggest that there were different miRNA and mRNA profiles after asthma induction and BM-MSCs treatment, and the miR-21/Acvr2a axis is an important mechanism for the induction of asthmatic inflammation.

Synthesis of novel pleuromutilin derivatives. Part 1: preliminary studies of antituberculosis activity.

The worldwide threat from tuberculosis (TB) has resulted in great demand for new drugs, particularly those that can treat multidrug-resistant TB. We synthesized novel pleuromutilin derivatives with N-benzylamine side chain substituted at the C14 position and evaluated their activity in vitro against a virulent strain of Mycobacterium tuberculosis (H37Rv). The primary assay results showed that five compounds inhibited the H37Rv at 20µM, with a MIC of one of the analogues as low as 7.2µM.