Berberine improves central memory formation of CD8+ T cells: Implications for design of natural product-based vaccines

Berberine (BBR) as one of the most effective natural products has been increasingly used to treat various chronic diseases due to its immunosuppressive/tolerogenic activities. However, it is unknown if BBR can be applied without abrogating the efforts of vaccination. Here we show that priming of CD8+ T cells in the presence of BBR lead to improved central memory formation (Tcm) with substantially reduced effector proliferation, primarily orchestrated through activation of AMPK and Stat5. Tcm derived from vaccinated mice fed with BBR were able to adoptively transfer protective immunity to naïve recipients. Vaccination of BBR-fed mice conferred better memory protection against infection without losing immediate effector efficacy, suggesting appreciable benefits from using BBR in vaccination. Thus, our study may help to lay the groundwork for mechanistic understanding of the immunomodulatory effects of natural products and their potential use as adjuvant that allows the design of novel vaccines with more desirable properties.

Effects of Paclitaxel and Quizartinib Alone and in Combination on AML Cell Line MV4-11 and Its STAT5 Signal Pathway / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of paclitaxel, quizartinib and their combination on proliferation, apoptosis and FLT3/STAT5 pathway of human leukemia cell line MV4-11 (FLT3-ITD+).@*METHODS@#MV4-11 cells were treated with paclitaxel and quizartinib at different concentrations for 24 h, 48 h and 72 h, respectively, and then the two drugs were combined at 48 h to compare the inhibition of proliferation, the apoptosis rate was detected by flow cytometry, the expression of FLT3 and STAT5 mRNA was determined by fluorescence quantitative PCR, and the protein expression of FLT3, p-FLT3, STAT5 and p-STAT5 was determined by Western blot.@*RESULTS@#Different combination groups of paclitaxel and quizartinib had synergistic inhibitory effect. The cell survival rate in the combination group was significantly lower than that in the single drug group (P<0.05). The cell apoptosis rate in the combination group was significantly higher than that in the single drug group (P<0.001). The expression of FLT3 mRNA in combination group was significantly higher than that in two single drugs (P<0.01). The expression of STAT5 mRNA in combination group was significantly higher than that in quizartinib group (P<0.001); increased compared with paclitaxel group, but there was no statistical significance. The expression level of p-FLT3、p-STAT5 protein in the combination group was significantly lower than that in the single drug group (P<0.05, P<0.05).@*CONCLUSION@#Paclitaxel combined with quizartinib can synergistically inhibit the proliferation of MV4-11 cell line and promote the apoptosis of MV4-11 cell line by inhibiting the activity of FLT3/STAT5 pathway.

Association of signal transducer and activator of transcription 3 and signal transducer and activator of transcription 5 with regulatory T cell/T helper 17 cell balance in chronic hepatitis B / 临床肝胆病杂志

The immune mechanism of chronic hepatitis B (CHB) persistent infection is closely associated with T cells, and the development of T cells requires the coordination of a variety of cytokines. The proteins of the signal transducer and activator of transcription (STAT) family are mainly involved in the signal transduction of cytokines, and STAT5a/b and STAT3 play an important role in the differentiation and development of regulatory T cells (Treg) and T helper 17 cells (Th17). This article analyzes the association of STAT3 and STAT5 with Treg/Th17 balance in CHB and investigates the chronicity of hepatitis B virus infection and the regulatory mechanism of liver inflammation.

Synergistic role of JAK/STAT5 and PI3K/AKT signaling pathways in regulating eIF4B in acute leukemia / 生物工程学报

Human acute leukemia (AL) is a clonal malignancy with abnormal hematopoietic stem cells. Clinically, AL is very difficult to cure due to its sudden onset and short course of disease progression. Previous studies have shown that eukaryotic initiation factor 4B (eIF4B) plays a critical role in the development of chronic leukemia. However, the involvement of eIF4B in human acute leukemia is still largely unknown. Therefore, we studied eIF4B function and its regulatory mechanism in human acute leukemia. We found that phosphorylation levels of eIF4B in acute leukemia cells were significantly reduced in response to treatment with either LY294002 (PI3K inhibitor), AKTi (AKT inhibitor) or SMI-4A (Pim inhibitor). Co-treatment with inhibitors targeting JAK/STAT5/Pim and PI3K/AKT/mTOR signaling dramatically promoted apoptosis of acute leukemia cells by downregulating eIF4B phosphorylation. Furthermore, in vitro and in vivo functional experiments showed that eIF4B played an important anti-apoptosis role in the acute leukemia cells by regulating the expression of anti-apoptotic proteins Bcl-2 and Bcl-XL. In contrast, silencing eIF4B inhibited the growth of acute leukemia cells as engrafted tumors in nude mice. Taken together, our results indicate the synergistic role of JAK/STAT5/Pim and PI3K/AKT/mTOR signaling pathways in regulating eIF4B phosphorylation in acute leukemia, and highlight eIF4B as a candidate therapeutic target for treatment of acute leukemia.

Effects of growth hormone in the central nervous system

ABSTRACT Growth hormone (GH) is best known for its effect stimulating tissue and somatic growth through the regulation of cell division, regeneration and proliferation. However, GH-responsive neurons are spread over the entire central nervous system, suggesting that they have important roles in the brain. The objective of the present review is to summarize and discuss the potential physiological importance of GH action in the central nervous system. We provide evidence that GH signaling in the brain regulates the physiology of numerous functions such as cognition, behavior, neuroendocrine changes and metabolism. Data obtained from experimental animal models have shown that disruptions in GH signaling in specific neuronal populations can affect the reproductive axis and impair food intake during glucoprivic conditions, neuroendocrine adaptions during food restriction, and counter-regulatory responses to hypoglycemia, and they can modify gestational metabolic adaptions. Therefore, the brain is an important target tissue of GH, and changes in GH action in the central nervous system can explain some dysfunctions presented by individuals with excessive or deficient GH secretion. Furthermore, GH acts in specific neuronal populations during situations of metabolic stress to promote appropriate physiological adjustments that restore homeostasis. Arch Endocrinol Metab. 2019;63(6):549-56

Relationship between Stat5b Expression in Cervical Tissues and Lesions / 中国医科大学学报

Objective To investigate the expression of signal transducer and activator of transcription 5 b (Stat5 b) and its phosphorylation (p-Stat5 b) in cervical lesions, its relationship with different degrees of cervical lesions, and its role in the pathogenesis and development of cervical lesions. Methods We obtained 80 specimens, including normal cervical tissues, low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), and cervical cancer tissues. To analyze the correlation between Stat5 b and the degree of cervical lesions, immunohistochemical staining was performed to detect Stat5 b and p-Stat5 b expression. Results Increased Stat5 b expression had a positive correlation with the development of cervical lesions. The percentages of Stat5 b expressed in normal tissues, LSIL, HSIL, and cervical cancer tissues were 15.0％, 0.0％, 50.0％, and 80.0％, respectively, with significant differences among the groups (P ＜ 0.05). Conversely, the expression of p-Stat5 b had a negative correlation with the development of cervical lesions.Expression of p-Stat5 b in normal tissues, LSIL, HSIL, and cervical cancer tissues was 80.0％, 45.0％, 5.0％, and 0.0％, respectively, with statistically significant differences among the groups (P ＜ 0.05). Conclusion The expression of Stat5 b is significantly different in different degrees of cervical lesions, suggesting that Stat5 b signaling molecules may be involved in the development of cervical lesions.

Protective effect of likun preparation no. 1 on bone marrow suppression in mice and its molecular mechanism / 中国药理学通报

To explore the protective effectof Likun preparation No.1 on bone marrow suppression injury in mice and the possible mechanism. Methods Sixty male BALB/c mice were randomly divided into normal control group, 5-Fu model group, positive control group(rhG-CSF) and Likun preparation No.1 groups with low, medium and high doses. Myocardial inhibition was established by intraperitoneal injection of 5-fluorouracil once. After seven days of administration, blood routine analysis was performed. Serum levels of TNF-α and IL-2 were detected by ELISA. The expression of p-JAK2 and p-STAT5 protein in spleen tissues were determined by Western blot. Results After given the Likun preparation No.1, the symptoms of diarrhea in mice were alleviated, body weight increased(P < 0.05), and white blood cells, platelets and lymphocytes also increased(P < 0.05). ELISA test showed that the serum level of IL-2 in Likun preparation high-dose group was higher than that in model group(P < 0.05), and the TNF-α content was lower than that in model group(P < 0.05). Western blot analysis showed that compared with model group, the expression of p-JAK2 and p-STAT5 protein in spleen of mice in Likun preparation group was up-regulated(P < 0.05). Conclusions The Likun preparation No.1 has protective effect on 5-Fu-induced myelosuppression in mice. The molecular mechanism may be related to the up-regulation of p-JAK2 and p-STAT5 protein expression, the promotion of IL-2 production and the reduction of TNF-α secretion.

Efecto de Estradiol y Testosterona sobre la activación de la vía JAK2/STAT5 inducida por hormona de crecimiento / Estradiol and Testosterone effect on the activation of the JAK2/STAT5 pathway induced by growth hormone

Abstract: Sex hormones play a major role during pubertal growth. Estradiol (E2) and testosterone (T) levels progressively increase during puberty and in the presence of growth hormone (GH), growth velocity increases. Understanding the interactions between sex hormones and GH, may optimize the treatment of pubertal children with growth disorders. The aim of our study was to investigate possible molecular mechanisms which might potentiate longitudinal growth during puberty due to E 2or T combined with GH. We evaluated the GH/JAK2/STAT5 signaling pathway in the human hepatoma cell line HEPG2. Our results suggest that sex hormones potentiate the GH signaling pathway in a dose dependent fashion. Relatively low concentrations of E 2associated with GH induce a substantial activation of the GH pathway, whereas relatively high concentrations of T associated with GH produce a similar effect. These findings are concordant with the physiology of the pubertal growth spurt, which is an early event in girls (when E 2 circulating levels are low), and a late event in boys (when T circulating levels are high).

Resumen: Las hormonas sexuales, modulan el crecimiento durante la pubertad. Los niveles de estradiol (E2) y testosterona (T) aumentan progresivamente durante la pubertad y en combinación con la hormona de crecimiento (GH), producen un incremento en la velocidad de crecimiento en este período conocido como el "estirón puberal". El estudio de la interacción entre las hormonas sexuales y la GH, es de gran importancia para optimizar el tratamiento de niños(as) con alteraciones del crecimiento durante la pubertad. El objetivo de nuestro estudio fue investigar los posibles mecanismos que podrían potenciar el crecimiento longitudinal durante la pubertad, en especial las interacciones entre E 2o T en combinación con GH. Se evaluó la activación de la vía de señalización GH/JAK2/STAT5 frente al estímulo combinado con estas hormonas en cultivos celulares de hepatoma humana HEPG2. Nuestros resultados sugieren que existe un efecto potenciador de las hormonas sexuales sobre la vía de señalización de GH. Observamos que concentraciones relativamente bajas de E2 junto con GH producen una clara activación de la vía de señalización para GH, mientras que concentraciones relativamente altas de T junto con GH producen una activación similar. Estos hallazgos son concordantes con la fisiología del estirón puberal, que es más precoz en niñas (cuando los niveles circulantes de E2 son bajos), y más tardíos en varones (cuando los niveles circulantes de T son altos).

Correlation research between JAK2-STAT3/STAT5 signal pathway and CD4+T lymphocyte subsets in children with food allergy / 中国免疫学杂志

Objective:To investigate the regulation of JAK2-STAT3/STAT5 signaling pathway on CD4+T lymphocyte subsets in children with food allergy. Methods:78 children with food allergy from January 2015 to March 2017 in our hospital were enrolled as the allergy group,and 78 healthy children in our hospital were enrolled as the control group. All the patients were divided into A,B,C,D groups according to ages. A group was less than or equal to 1 year old,B group of 1-3 years old(not including 1 year old),group C 3-6 years old(not including 3 years old),group D 6-11 years old(not including 6 years old). Flow cytometry was used to detect the CD4+T lymphocyte subsets Th1,Th2,Th17 and regulatory T cells(Treg) and qPCR was used to detect the mRNA expression of peripheral blood mononuclear cells of JAK2,STAT3,STAT5. Compare the CD4+T lymphocyte subsets and JAK2,STAT3,STAT5 expression level differences among two groups children and further analysis the correlation of JAK2-STAT3/STAT5 signal transduction pathway and CD4+T lymphocyte subsets. Results:The percentage of Th1 and Treg lymphocytes and Th1/Th2 and Treg/Th17 ratio of the group A,B, C in control group were significantly higher than the allergy group,while Th2,Th17 lower than allergy group. The expression mRNA level of JAK2,STAT3 and STAT5 in the control group were significantly lower than the allergic group,the difference was statistically significant(P＜0. 05). The correlation for JAK2,STAT3,STAT5 and CD4+T level of lymphocyte subsets were compared,correlation coefficient of Th1,Treg,Th1/Th2,Treg/Th17 were all higher than 0(P＜0. 05),and the correlation coefficient of Th2 and Th17 were smaller than 0(P＜0. 05). However in group D,there was no significance. Conclusion:The JAK2-STAT3/STAT5 signaling pathway in young children with food allergy has obvious activation and CD4+T lymphocyte subsets change,and the JAK2-STAT3/STAT5 signaling pathway can effectively regulate the distribution of CD4+T lymphocyte subsets. With the age of children increasing,the correlation of these effects is weakened and disappeared.

Effect of silencing GRAMD1A and inhibiting STAT5 signaling pathway on radiosensitivity of hepatocellular carcinoma cell line Huh7 / 中华放射医学与防护杂志

Objective@#To investigate the effect of silencing GRAMD1A and inhibiting STAT5 signaling pathway on the radiosensitivity of Huh7 cells in order to provide new ideas for the clinical combined therapy of hepatocellular carcinoma.@*Methods@# The Huh7 cells silencing GRAMD1A was constructed by infecting lentivirus and verified by qPCR and Western blot. QPCR and luciferase reporter assays were used to detect the effect of silencing GRAMD1A on the expression of STAT5 and its downstream genes. Colony formation and apoptosis were detected to evaluate the effects of silencing GRAMD1A and STAT5 inhibitor SH-4-54 on cell radiosensitivity.@*Results@#After 2 Gy exposure of the constructed Huh7 cells, the colony formation ability of the silencing GRAMD1A combined irradiation group was significantly lower than that of the negative control combined irradiation group, and the difference was statistically significant (t=8. 494, P<0.05). Silence apoptosis in the GRAMD1A combined irradiation group was significantly increased compared with the negative control combined irradiation group (t=3.560, P<0.05). After silencing GRAMD1A, the radiosensitivity of Huh7 cells was significantly increased, and the expression of STAT5 and its downstream genes was significantly reduced in cells.The survival rate of the SH-4-54 inhibitor combined irradiation group was significantly lower than that of the dimethyl sulfoxide combined irradiation group, and the difference was statistically significant (t=8.660, P<0.05). SH-4-54 inhibited STAT5 after passage, the radiosensitivity of Huh7 cells was significantly increased.@*Conclusions@# Silencing GRAMD1A could significantly enhance the radiosensitivity of Huh7 cells via STAT5 signaling pathway, indicating that GRAMD1A plays an important role in the development and progression of HCC. This finding may provide a new target for HCC therapy.

Inhibitory effect of JQ1 on proliferation of acute myeloid leukemia U937 cell line and its effect on the signal transduction pathway of STAT-5 / 白血病·淋巴瘤

Objective To study the suppressive mechanism of the bromo structural domain inhibitor JQ1 on the acute myeloid leukemia cell line U937 and its regulation of the STAT-5 signaling pathway. Methods U937 cells in the logarithmic growth phase were tested. Each experimental group was fed with 0.2, 1.0 and 4.0μmol/L of JQ1, and a blank control group without JQ1 was set up. U937 cells were cultured for 48 h, and the cell proliferation inhibitory rate was measured by MTT assay. Flow cytometry (FCM) was used to detect the apoptotic rate. Real-time fluorescence quantitative polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of focal adhesion kinase (FAK) and P21 activated kinase (PAK1). The expression of STAT-5 protein was analyzed by Western blot. Results Different concentration of JQ1 could inhibit the proliferation of U937 cells in a time and dose-dependent manner, and different concentration of JQ1 could induce the apoptosis of U937 cells in a dose-dependent manner. Treatment of U937 cells with different concentrations of JQ1 (0.2, 1.0 and 4.0 μmol/L) reduced the expression of FKA mRNA and PAK1 mRNA after 48 h, the expression of FAK mRNA was 0.417±0.066, 0.140±0.026, and 0.027±0.006 (F=454.651, P=0.000), and the expression of PAK1 mRNA was 0.533±0.045, 0.080±0.010, and 0.010±0.001 (F=2434.610, P= 0.000), and STAT-5 protein expression was also significantly inhibited. The expression of STAT-5 protein in U937 cells after treated with different concentrations of JQ1 (0.2, 1.0 and 4.0 μmol/L) for 48 h were 0.71± 0.19, 0.62±0.16, 0.53±0.14, and 1.00±0.21 in the control group (F= 263.135, P= 0.000). Conclusion JQ1 can effectively inhibit the proliferation of the acute myeloid leukemia cell line U937 cells and induce their apoptosis, and the possible mechanism of action is regulated via STAT-5 signaling pathway.

Growth hormone insensitivity with immune dysfunction caused by a STAT5B mutation in the south of Brazil: evidence for a founder effect

ABSTRACT Homozygous STAT5B mutations causing growth hormone insensitivity with immune dysfunction were described in 10 patients since 2003, including two Brazilian brothers from the south of Brazil. Our objectives were to evaluate the prevalence of their STAT5B mutation in this region and to analyze the presence of a founder effect. We obtained DNA samples from 1,205 local inhabitants, 48 relatives of the homozygous patients and four individuals of another affected family. Genotyping for STAT5B c.424_427del mutation and for two polymorphic markers around it was done through fragment analysis technique. We also determined Y-chromosome and mtDNA haplotypes and genomic ancestry in heterozygous carriers. We identified seven families with STAT5B c.424_427del mutation, with 33 heterozygous individuals. The minor allelic frequency of this mutation was 0.29% in this population (confidence interval 95% 0.08-0.5%), which is significantly higher than the frequency of other pathogenic STAT5B allele variants observed in public databases (p < 0.001). All heterozygous carriers had the same haplotype present in the homozygous patients, found in only 9.4% of non-carriers (p < 0.001), supporting the existence of a founder effect. The Y-chromosome haplotype, mtDNA and genomic ancestry analysis indicated a European origin of this mutation. Our results provide compelling evidence for a founder effect of STAT5B c.424_427del mutation.

The mechanism of STAT5-ROS signal pathway to mediated imatinib resistance of K562 cells / 安徽医科大学学报

Objective To investigate the mechanism of STAT5-ROS pathway to mediate IM resistance of K562 cells.K562 cells were cultured with imatinib at gradually increased concentrations to generate resistance cell line.Methods CCK-8 assay was used to clarify the resistance ratio.The STAT5A and STAT5B mRNA levels were detected by RT-PCR.Flow cytometry assay was used to detect the level of ROS and cell apoptosis.The expression of STAT5 protein was detected by Western blot.Results Imatinib resistance cell line K562/G was successfully induced by gradually increasing concentrations of IM.The IC50 of K562/G was eighty times higher than K562 by CCK-8.Cell growth curve showed that K562/G was not inhibited in 20 μmol/L imatinib, whereas the K562 cell was significantly inhibited by up to 0.1 μmol/L imatinib.Intracellular level of ROS in K562/G was obviously higher than that of K562 cells(P=0.000 1).The apoptosis ratio of K562 was lower than that of K562/G when the same concentration of IM react on the two cell lines for the same time(P<0.05).The expression of STAT5A and STAT5B mRNA in K562/G was higher than in K562(P=0.000 1,P=0.017 0).Then,the level of STAT5 proteins in K562/G cells was significantly increased (P=0.009 0).Conclusion The STAT5 is highly expressed in CML.STAT5-ROS is closely related to the formation of imatinib resistance of chronic myeloid leukemia.

3,3'-Diindolylmethane Inhibits Flt3L/GM-CSF-induced-bone Marrow-derived CD103+ Dendritic Cell Differentiation Regulating Phosphorylation of STAT3 and STAT5

The intestinal immune system maintains oral tolerance to harmless antigens or nutrients. One mechanism of oral tolerance is mediated by regulatory T cell (Treg)s, of which differentiation is regulated by a subset of dendritic cell (DC)s, primarily CD103+ DCs. The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, plays an important role in regulating immunity. The intestines are exposed to various AhR ligands, including endogenous metabolites and phytochemicals. It was previously reported that AhR activation induced tolerogenic DCs in mice or in cultures of bone marrow-derived DCs. However, given the variety of tolerogenic DCs, which type of tolerogenic DCs is regulated by AhR remains unknown. In this study, we found that AhR ligand 3,3'-diindolylmethane (DIM) inhibited the development of CD103+ DCs from mouse bone marrow cells stimulated with Flt3L and GM-CSF. DIM interfered with phosphorylation of STAT3 and STAT5 inhibiting the expression of genes, including Id2, E2-2, IDO-1, and Aldh1a2, which are associated with DC differentiation and functions. Finally, DIM suppressed the ability of CD103+ DCs to induce Foxp3+ Tregs.

Effect of STAT5 Pathway Inhibitor Pimozide on NO and iNOS Expressions in the Inflammation Model of RAW264.7 Cell / 中国药房

OBJECTIVE:To investigate the effect of STAT5 pathway inhibitor pimozide on the expressions of nitric oxide (NO)and nitric oxide synthetase(iNOS)in the model of mouse macrophage RAW264.7 inflammation induced by lipopolysaccha-ride (LPS). METHODS:RAW264.7 cells in logarithmic growth phase were divided into blank control group,drug control group (10μmol/L pimozide),model group(1μg/ml LPS)and the pimozide groups of low,middle and high doses(2.5,5 and 10μmol/L), where the corresponding cells were given pimozide 30 min before the administration of LPS,and then were cultured for 24 h. Griess method was used to determine the content of NO in the supernate of cell culture solutions of all groups,real-time quantita-tive polymerase chain reaction(RT-PCR)to determine iNOS mRNA expression,and Western blot method to determine the protein expression of iNOS and phosphorylated STAT5(p-STAT5). RESULTS:The content of NO,iNOS mRNA and protein expressions and the content of p-STAT5/STAT5 in the cells in the model group were higher than those in the blank control group,with statisti-cally difference (P<0.01). Compared to the model group,the pimozide groups of middle and high doses had lower content of NO,iNOS mRNA and protein expressions and the content of p-STAT5/STAT5 in the cells,with statistically difference(P<0.01 or P<0.05). CONCLUSIONS:STAT5 pathway inhibitor pimozide can inhibit the release of NO by inhibiting iNOS mRNA and pro-tein expressions in cells.

Exposure to PAHs reduced the number and suppressed the function of regulatory T cells in newborns / 中华微生物学和免疫学杂志

Objective To investigate the effects of polycyclic aromatic hydrocarbons ( PAHs) on regulatory T ( Treg) cells in newborns.Methods Blood samples were taken from the umbilical cord of sev-en newborn babies.CD4+CD25+T cells were isolated and treated with or without 300 nmol/L of phenan-threne for 72 hours in the presence of 100 IU/ml of IL-2.The expression of forkhead box P3 (Foxp3), sig-nal transducer and activator of transcription 3 (STAT3) and STAT5 were analyzed by 8-color flow cytometry. RT-PCR was performed to detect the expression of DNA ( cytosine-5 )-methyltransferase 1 ( DNMT1 ) , DNMT3a, DNMT3b and IL-4 at mRNA level.Pyrosequencing in combination with bisulphite sequencing was used to evaluate the methylation within the promoter and the Treg-specific demethylated region ( TSDR) of Foxp3 locus.Treg cells were cultured for 7 hours with autologous Tresp at Tresp/Treg ratios of 1 ∶1, 2 ∶1, 4 ∶1 and 8 ∶1 and stimulated with anti-CD3/CD28 beads and IL-2 for the evaluation of the immunosuppres-sive activities of Treg cells.Results (1) PAHs inhibited the expression of Foxp3 and the function of Treg cells collected from newborns.(2) PAHs significantly decreased the expression of STAT5 and Foxp3, but increased the expression of STAT3 (P<0.05).(3)PAHs enhanced the methylation of the promoter and the TSDR within Foxp3 gene.(4) The transcription levels of DNMT1, DNMT3a and DNMT3b in PAHs treated group were significantly higher than those of the control group (P<0.05).(5) More IL-4 was secreted by PAHs treated CD4+CD25+T cells, indicating that IL-4 was negatively correlated with STAT5, but positively correlated with STAT3.Conclusion PAHs decreased the number and inhibited the function of Treg cells in newborns.The possible mechanism might be related to the abnormal expression of STAT3 and STAT5 in-duced by IL-4 as well as the methylation within Foxp3 gene.

Influence of transcription factor Stat5a on proliferation of human breast cancer cells and its epigenetic mechanisms / 重庆医学

Objective To investigate and clarify the effect of Stat5a on proliferation of human breast cancer cells (MCF‐7) and to detect the changes of epigenetic signature on the promoter region of p53 gene .Methods Stat5a was over expressed in human breast cancer cells (MCF‐7) by using adenovirus mediated gene transfer technology .The cell proliferation was examined by MTS assay .ChIP assay was used to check the trimethylation of lysine 27 on histone 3 (H3K27Me3) of p53 gene promoter region .Fur‐thermore ,qRT‐PCR and western blot were also applied to confirm the expression of p53 gene .Results The number of MCF 7 in‐creased in a dose dependent manner .Compared with that of control group ,the cell density of MCF‐7 increased 7 .603 1% , 18 .123 7% and 24 .898 7% when the MOI were 10 ,20 and 30 .Chromatin Immunoprecipitation showed that Stat5a significantly in‐creased H3K27Me3 and down regulated the expression level of p53 gene .Conclusion Stat5a promotes proliferation of breast cancer cells through trimethylation of H3K27 and inhibition of p53 gene expression .

Correlation of growth hormone receptor and its signal pathway defects with the phenotype: A study of 21 cases with growth hormone insensitivity syndrome / 中华内分泌代谢杂志

Objective To detect the relationship between the molecular defects and their phenotypes in children with growth hormone insensitivity syndrome (GHIS).Methods 21 patients defined as GHIS were enrolled in the study.4 candidate genes (GHR,IGFALS,JAK2,and STAT5B) were analyzed by genomic DNA sequence screening and clinical relevance analysis.Results The statistical descriptions of the patients were showed as an average height standard deviation (SDS)-4.33 ± 1.91 (-9.17 to-2.21),average serum peak values of GH (22.67 ±20.98) tg/L (11.33 to 104.21 μg/L),basal serum insulin-like growth factor-Ⅰ SDS-2.65 ± 0.53 (-3.57 to -1.79),insulin-like growth factor-binding protein 3 SDS-1.77 ± 1.64 (-4.13 to 0.96).Bone age of backward difference (chronological age-bone age) (43.10 ± 19.54) months (6 to 82 months).One of two children with severe growth failure and mid-face hypoplasia was found to a homozygote for G to A gene mutation in the intron 6 splice donor consensus sequences (IVS6 ds+ 1 G-A) in the GHR gene,causing its functional defect.3 cases with mild dwarf were found gene variations as novel finding:c.1097T＞C c.1098C＞T p.V366A pathogenic variant,c.1229C＞T p.S410L and nt1843707 A→G of 5' UTR region in the IGFALS gene.JAK2 and STAT5b genes mutations were not found.Conclusion Molecular pathology of GHIS is considered as involving the defects of GHR and its signal pathway.The mutation of intron 6 splice donor sequences in GHR gene has been reported which affect the function of GHR.The 3 novel type base variants in IGFALS gene,causing non severe dwarfism,might be suspected with pathogenic roles of GHIS.

Deficiência da STAT5B: uma nova síndrome de insensibilidade ao hormônio de crescimento associada a acometimento imunológico / STAT5B deficiency: a new growth hormone insensitivity syndrome associated to immunological dysfunction

Uma nova apresentação da insensibilidade ao hormônio de crescimento (IGH), causada por mutações em homozigose no gene STAT5B (transdutor de sinal e ativador de transcrição tipo 5B), foi caracterizada nos últimos anos. Sua particularidade é a associação com quadros de disfunção imunológica grave, sendo o mais característico a pneumonite intersticial linfocítica. A presença concomitante de doenças crônicas imunológicas pode fazer com que a baixa estatura seja erroneamente considerada uma consequência do quadro clínico, levando ao subdiagnóstico dessa forma de IGH. O objetivo desta revisão é divulgar o conhecimento atual sobre essa rara patologia, facilitando o reconhecimento de pacientes com IGH secundária a mutações no gene STAT5B em ambulatórios de endocrinologia e de outras especialidades.

A new presentation of growth hormone insensitivity (GHI) caused by homozygous mutations in STAT5B (signal transducer and activator of transcription 5B) gene has been characterized in the last years. Its particularity is the association with severe immune dysfunction, especially with lymphocytic interstitial pneumonitis. This may mislead physicians into considering short stature as secondary to chronic immunological disease and consequently into underdiagnosing this form of GHI. The objective of this review is to propagate current knowledge about this rare pathology, facilitating the diagnosis of patients with GHI due to STAT5B mutations in endocrinology and other specialties clinics.

Differential Expression of STATs and Its Function in Osteogenesis of Mesenchymal Stem Cells / 대한정형외과연구학회지

PURPOSE: To investigate the role of STAT5 during osteogenesis differentiation of human mesenchymal stem cells(hMSC). MATERIALS AND METHODS: To assess the expression pattern of STATs during osteogenic differentiation, we performed western blot analysis and RT-PCR. By RNA interference, we have performed effect of STAT5A and STAT5B in osteogenesis. As a result of Luciferase assay, the promoter activity of DLX5 was decreased by STAT5A. RESULTS: To assess the expression pattern of STATs during osteogenic differentiation, we have performed western blot and RT-PCR after 14 day differentiation period. STAT1, 2, 3 and 4 showed no change in expression level during differentiation, while STAT5A and STAT5B displayed steady increase compared to the control. When STAT5A was knock down, the level of osteogenesis was increased. The transcriptional activity of DLX5 was decreased about 70% by STAT5A. CONCLUSION: The expression of STAT5A and STAT5B increased during osteogenesis of hMSC. Also, we shown that STAT5A regulated the transcriptional activity of DLX5. These results indicate that STAT5A acts as a pivotal transcription factor in osteogenesis of hMSC.