Human umbilical cord-derived mesenchymal stem cells protect from hyperoxic lung injury by ameliorating aberrant elastin remodeling in the lung of O2-exposed newborn rat.

The incidence and mortality rates of bronchopulmonary dysplasia (BPD) remain very high. Therefore, novel therapies are imminently needed to improve the outcome of this disease. Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) show promising therapeutic effects on oxygen-induced model of BPD. In our experiment, UC-MSCs were intratracheally delivered into the newborn rats exposed to hyperoxia, a well-established BPD model. This study demonstrated that UC-MSCs reduce elastin expression stimulated by 90% O2 in human lung fibroblasts-a (HLF-a), and inhibit HLF-a transdifferentiation into myofibroblasts. In addition, the therapeutic effects of UC-MSCs in neonatal rats with BPD, UC-MSCs could inhibit lung elastase activity and reduce aberrant elastin expression and deposition in the lung of BPD rats. Overall, this study suggested that UC-MSCs could ameliorate aberrant elastin expression in the lung of hyperoxia-induced BPD model which may be associated with suppressing increased TGFß1 activation.

[Respiratory physicians' knowledge, attitude and practice of tobacco control and their smoking status in the city of Chongqing].

OBJECTIVE: To investigate the smoking status, knowledge of smoking hazards, attitude of tobacco control and skill of assisting smoking cessation in respiratory physicians in the city of Chongqing and therefore to provide references for their further participation in social tobacco control. METHODS: With a self-designed questionnaire, a cross-sectional study was conducted on respiratory physicians of 8 hospitals in Chongqing, which were selected with stratified random sampling method. All the data were inputted with software Epidata 3.1 and were analyzed with SPSS 13.0. RESULTS: A total of 428 valid questionnaires were retrieved, with a valid rate of 95.1% (428/450). The total smoking rate was 12.4% (95%CI: 9.3% - 15.5%), with 7.4% in physicians of teaching hospitals, 8.13% in those of hospitals located in urban areas, and 19.0% in those of hospitals located in suburban district counties. The differences in smoking rates in the respiratory physicians among different hospitals showed statistical significance (χ(2) = 11.734, P = 0.014). The smoking rate of the male was higher than that of the female. Of the surveyed doctors, 80.14% had awareness that tobacco dependence was a neuropsychiatric disease characterized as nicotine addiction, while 34.8% claimed that they had no idea about quitting smoking drugs. Although all participants claimed that they knew the harm of secondhand smoke, 16.36% of them still had never come forward to prevent smoking behavior in hospitals. There was only 27.4% of the surveyed discouraging smoking behavior with the reason of unwillingness to breath in secondhand smoke, while 53.9% of the surveyed discouraged smoking behavior because of regulations of hospitals. Most of the surveyed did relatively well in routinely inquiring and recording the smoking status of patients, but only 27.1% of them had recommended specific quitting smoking methods to patients, and there were few successful cases in practice. The situations of smoking cessation assistance in hospitals located in urban areas and suburban district counties were better than that in teaching hospitals. CONCLUSIONS: The smoking rate of the respiratory physicians (especially male doctors) in Chongqing is high. There is lack of enthusiasm in preventing smoking behavior in public area of hospitals. The knowledge and skills of smoking cessation are lacking as well. Therefore more training programs for smoking control are needed. Respiratory physicians in primary hospitals or community health centers can play a more important role in smoking control.

S1P-S1PR3-RAS promotes the progression of S1PR3hi TAL1+ T-cell acute lymphoblastic leukemia that can be effectively inhibited by an S1PR3 antagonist.

TAL1+ T-cell acute lymphoblastic leukemia (T-ALL) is a distinct subtype of leukemia with poor outcomes. Through the cooperation of co-activators, including RUNX1, GATA3, and MYB, the TAL1 oncoprotein extends the immature thymocytes with autonomy and plays an important role in the development of T-ALL. However, this process is not yet well understood. Here, by investigating the transcriptome and prognosis of T-ALL from multiple cohorts, we found that S1PR3 was highly expressed in a subset of TAL1+ T-ALL (S1PR3hi TAL1+ T-ALL), which showed poor outcomes. Through pharmacological and genetic methods, we identified a specific survival-supporting role of S1P-S1PR3 in TAL1+ T-ALL cells. In T-ALL cells, TAL1-RUNX1 up-regulated the expression of S1PR3 by binding to the enhancer region of S1PR3 gene. With hyperactivated S1P-S1PR3, T-ALL cells grew rapidly, partly by activating the KRAS signal. Finally, we assessed S1PR3 inhibitor TY-52156 in T-ALL patient-derived xenografts (PDXs) mouse model. We found that TY-52156 attenuated leukemia progression efficiently and extended the lifespan of S1PR3hi TAL1+ T-ALL xenografts. Our findings demonstrate that S1PR3 plays an important oncogenic role in S1PR3hi TAL1+ T-ALL and may serve as a promising therapeutic target.

Type 2 Alveolar Epithelial Cells Differentiated from Human Umbilical Cord Mesenchymal Stem Cells Alleviate Mouse Pulmonary Fibrosis Through ß-Catenin-Regulated Cell Apoptosis.

Pulmonary fibrosis (PF) is a chronic, progressive, and lethal disease with little response to available therapies. One of the major mechanisms of PF is the repeated injury and inadequate regeneration of the alveolar epithelium. In this study, we induced human umbilical cord mesenchymal stem cells (hUC-MSCs) to differentiate into type 2 alveolar epithelial cells (AEC2s), and we provided evidence that intratracheal transplantation of hUC-MSC-derived AEC2s (MSC-AEC2s) could improve mortality and alleviate fibrosis in bleomycin-induced PF mice. Transplantation of MSC-AEC2s could increase the AEC2 cell count in these mice, and the results of the cell tracing experiment exhibited that the increased AEC2s originated from the self-renewal of mouse alveolar epithelium. The AEC2 survival was controlled by the apoptosis of AEC2s via the expression of ß-catenin in PF mice. In in vitro experiments, MSC-AEC2s could alleviate the apoptosis of MLE-12 cells induced by transforming growth factor beta (TGF-ß1), which could be eliminated by using PRI-724, a ß-catenin inhibitor, suggesting ß-catenin signaling involved in the protection against apoptosis provided by MSC-AEC2s. Our study demonstrated that MSC-AEC2s could protect PF mice through regulating apoptosis mediated by ß-catenin, which provided a viable strategy for the treatment of PF.

Integrative identification of the pathogenic role of a novel G6PD missense mutation c.697G>C.

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a hereditary disease caused by pathogenic mutations of G6PD. While most of the pathogenic variants of G6PD have been annotated, hemolysis of unknown etiology but analogous to that in G6PD deficiency persists, implying the existence of undocumented pathogenic variants. In our previous study, we reported four novel G6PD variants in China, for which the pathogenicity remains to be verified. METHODS: The variants were verified by exogenous expression in HEK-293 cells, and their functions were predicted by PolyPhen-2 and SIFT. The CRISPR/Cas9 system was exploited to edit the G6PD c.697G>C variant in HEK-293 cells and K562 cells. The expression of G6PD was detected by quantitative PCR (qPCR) and western blotting. The cell growth capacity was detected by the CCK-8 assay and crystal violet staining. The G6PD enzyme activity was reflected by the G6P/6PG ratio test. The apoptosis of cells was detected by Annexin V-APC/7-AAD staining. The secondary and crystallographic structures were denoted according to the literature and PyMOL software. The G6PD protein was purified from lysis of transformed Escherichia coli (E. coli) cell with Ni-charged Resin Column. The enzymatic activity was detected at different temperatures. RESULTS: The G6PD activity of exogenous G6PD c.697G>C in HEK-293 cells was significantly lower than that of wild type (WT) G6PD, a finding that was consistent with the observation in clinical samples. The functional predictions conducted by different algorithms indicated the damage role of the G6PD c.697G>C variant in its enzymatic activity. We recapitulated the G6PD c.697G>C variant both in HEK-293 cells and K562 cells by adapting the CRISPR/Cas9 strategy. Using distinct cell lines expressing the G6PD c.697G>C variant endogenously, we confirmed the deteriorative role of the G6PD c.697G>C variant in its enzymatic activity. Regarding the secondary and crystallographic structure, we found a mutated amino acid approaching the structural NADP+ binding site. Finally, we demonstrated the c.697G>C variant compromised the thermal stability of G6PD protein. CONCLUSIONS: Our data delineated the pathogenic role of G6PD c.697G>C variant for G6PD deficiency, implying the wide usage of CRISPR/Cas9 for genetic disease research.

Mesenchymal stem cells as a potential therapy for COVID-19.

The outbreak of 2019 novel coronavirus disease (COVID-19) worldwide is becoming rapidly a major concern. The number of severe cases has increased dramatically worldwide, while specific treatment options are scarce. The main pathologic features of severe or critical COVID-19 were consistent with acute lung injure (ALI)/acute respiratory distress syndrome (ARDS), characterized by cellular fibromyxoid exudates, extensive pulmonary inflammation, pulmonary edema, and hyaline membrane formation. Mesenchymal stem cells (MSCs) can balance the inflammatory response and has been mentioned to be effective on ALI/ARDS from both infectious and noninfectious causes previously, presenting an important opportunity to be applied to COVID-19. In this commentary, we summarize the clinical trials of MSCs treatments on ALI/ARDS and raise MSCs as a hopefully alternative therapy for severe or critical COVID-19.

ARRB1-Promoted NOTCH1 Degradation Is Suppressed by OncomiR miR-223 in T-cell Acute Lymphoblastic Leukemia.

T-cell acute lymphoblastic leukemia (T-ALL) is a type of aggressive leukemia with inferior prognosis. Although activating mutations of NOTCH1 are observed in most T-ALL cases, these mutations alone are not sufficient to drive the full development of T-ALL. ß-Arrestins (ARRB) are versatile and multifunctional adapter proteins that regulate diverse cellular functions, including promoting the development of cancer. However, the role of ARRBs in T-ALL has largely remained elusive. In this study, we showed that ARRB1 is expressed at low levels in assayed T-ALL clinical samples and cell lines. Exogenous ARRB1 expression inhibited T-ALL proliferation and improved the survival of T-ALL xenograft animals. ARRB1 facilitated NOTCH1 ubiquitination and degradation through interactions with NOTCH1 and DTX1. Mechanistically, the oncogenic miRNA (oncomiR) miR-223 targets the 3'-UTR of ARRB1 (BUTR) and inhibits its expression in T-ALL. Furthermore, overexpression of the ARRB1-derived miR-223 sponge suppressed T-ALL cell proliferation and induced apoptosis. Collectively, these results demonstrate that ARRB1 acts as a tumor suppressor in T-ALL by promoting NOTCH1 degradation, which is inhibited by elevated miR-223, suggesting that ARRB1 may serve as a valid drug target in the development of novel T-ALL therapeutics.Significance: These findings highlight a novel tumor suppressive function of the adaptor protein ß-arrestin1 in T-ALL.

Deletion of SMARCA4 impairs alveolar epithelial type II cells proliferation and aggravates pulmonary fibrosis in mice.

Alveolar epithelial cells (AECs) injury and failed reconstitution of the AECs barrier are both integral to alveolar flooding and subsequent pulmonary fibrosis (PF). Nevertheless, the exact mechanisms regulating the regeneration of AECs post-injury still remain unclear. SMARCA4 is a part of the large ATP-dependent chromatin remodelling complex SWI/SNF, which is essential for kidney and heart fibrosis. We investigates SMARCA4 function in lung fibrosis by establishing PF mice model with bleomycin firstly and found that the expression of SMARCA4 was mainly enhanced in alveolar type II (ATII) cells. Moreover, we established an alveolar epithelium-specific SMARCA4-deleted SP-C-rtTA/(tetO) 7 -Cre/SMARCA4 f/f mice (SOSM4 Δ/Δ ) model, as well as a new SMARCA4-deleted alveolar type II (ATII)-like mle-12 cell line. We found that the bleomycin-induced PF was more aggressive in SOSM4 Δ/Δ mice. Also, the proliferation of ATII cells was decreased with the loss of SMARCA4 in vivo and in vitro. In addition, we observed increased proliferation of ATII cells accompanied by abnormally high expression of SMARCA4 in human PF lung sections. These data uncovered the indispensable role of SMARCA4 in the proliferation of ATII cells, which might affect the progression of PF.

[Survivin antisense oligodeoxynucleotides inhibits the proliferation of hepatocellular carcinoma cells and enhances 5-FU sensitivity].

OBJECTIVE: To investigate the inhibitory effect of survivin antisense oligodeoxynuleotides (ASODN) mediated by polyethylenimine (PEI) on hepatocelluar carcinoma SMMC-7721 cell proliferation and its effect on chemosensitivity to 5-FU in tumor-bearing mice. METHODS: The inhibitory effect of PEI-ASODN on SMMC-7721 cell proliferation was assayed by WST-8 test, Trypan blue exclusion test, and cell clone formation assay. In mouse models of transplanted H22 cell hepatocarcinoma and ascites tumor, the effect of 5-FU combined with PEI-ASODN on the weight and volume of the subcutaneous tumors was examined. The tumor inhibition rate in the tumor-bearing mice was calculated and the average survival time recorded. RESULTS: SMMC-7721 cells incubated with different concentrations of PEI-ASODN for 48 h showed significantly reduced cell proliferation in comparison with the control cells, while PEI or ASODN alone produced no such inhibitory effect. Incubation of SMMC-7721 cells with 0.75 micromol/L PEI-ASODN for 24, 48, 72, and 96 h resulted in significantly suppressed cell proliferation, and a 7-day incubation of the cells with PEI-ASODN at different concentrations (0.25-0.75 micromol/L) significantly inhibited the cell clone formation. In the tumor-bearing mice, the tumor weight and volume were obviously reduced with a tumor inhibition rate of 56.91% and volume inhibition rate of 57.83%, significantly different from those in saline-treated mice (P<0.01). In the mice bearing ascites tumor, the average survival time was 22.0 days in saline group and 42.7 days in 5-FU+PEI-ASODN treatment group, showing a a life-prolonging rate of 94.09% in the latter group. A synergetic effect was noted between 5-FU and PEI-ASODN. CONCLUSION: PEI-ASODN complex can significantly inhibit the proliferation of hepatocarcinoma SMMC-7721 cells and enhance 5-FU chemosensitivity of the tumor cells in vitro and transplanted H22 tumors in mice.

[Survivin antisense oligodeoxynucleotides inhibits the proliferation of hepatocellular carcinoma cells and enhances the cell chemosensitivity to 5-Fu].

OBJECTIVE: To investigate the inhibitory effect of survivin antisense oligodeoxynucleotides (ASODN) mediated by polyethylenimine(PEI) on the proliferation of hepatocellular carcinoma SMMC-7721 cells, and assess its detect on the chemosensitivity of the cells to 5-FU. METHODS: The inhibitory effect of PEI-ASODN on SMMC-7721 cell proliferation was assessed using WST-8 test, trypan blue staining, and cell clone formation test. In mice bearing transplanted hepatocarcinoma and ascites tumor derived from H22 cells, 5-FU combined with PEI-ASODN was administered, and the weight and volume of the subcutaneous tumors were measured to calculate the tumor inhibition rate, and the average survival time of the mice was calculated. RESULTS: Incubation of the cells with different concentrations of PEI-ASODN for 48 h significantly inhibited the cell proliferation as compared with the control group, but PEI or ASODN alone produced no significant inhibitory effects. At 24, 48, 72, 96 h of incubation of the SMMC-7721 cells with 0.75 micromol/L PEI-ASODN, the cell proliferation was suppressed significantly, and incubation with PEI-ASODN at 0.25-0.75 micromol/L for 7 days resulted in significantly inhibited cell clone formation. No significant inhibition was detected in ASODN and PEI group. The tumor weight and volume were reduced in all the treated groups. The tumor inhibition rate was 56.91% and volume inhibition rate was 57.83% in 5-FU+PEI-ASODN group, significantly different from those in the normal saline group (P<0.01). In mice bearing ascites tumor, the average survival time was 22.0 days in saline group, and 42.7 days 5-FU+PEI-ASODN group. The life-prolongation rate of 5-FU+PEI-ASODN was 94.09% when compared with the survival time in saline group. A cooperative effect was detected between 5-FU and PEI-ASODN. CONCLUSION: PEI-ASODN complex can significantly inhibit the proliferation of hepatocarcinoma SMMC-7721 cells and enhance the chemosensitivity of the tumor cells to 5-FU.