Inhibitory Effect of Kaempferol on Proliferation of KG1a Cells and Its Mechanism / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of kaempferol on proliferation of acute myeloid leukemia (AML) KG1a cells and its mechanism.@*METHODS@#Human AML KG1a cells in logarithmic growth stage were taken and set at 25, 50, 75 and 100 μg/ml kaempferol group, another normal control group (complete medium without drug) and solvent control group (add dimethyl sulfoxide) were also set. After 24 and 48 hours of intervention, the cell proliferation rate was detected by CCK-8 assay. In addition, interleukin-6 (IL-6) combined with kaempferol group (Plus 20 μg/l IL-6 and 75 μg/ml kaempferol) was set up, 48 hours after culture, the cell cycle and apoptosis of KG1a cells were detected by flow cytometry, the mitochondrial membrane potential (MMP) of KG1a cells was detected by MMP detection kit (JC-1 method), and the expression of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway related proteins in KG1a cells were detected by Western blot.@*RESULTS@#The cell proliferation rate of 25, 50, 75 and 100 μg/ml kaempferol group decreased significantly (P<0.05), and with the increase of kaempferol dose (r24 h=-0.990, r48 h= -0.999), the cell proliferation rate decreased gradually (P<0.05). The inhibitory effect of 75 μg/ml kaempferol on cell proliferation reached half of effective dose after 48 hours of intervention. Compared with normal control group, the G0/G1 phase cell proportion and apoptosis rate of cells in 25, 50 and 75 μg/ml kaempferol group increased, while the S phase cell proportion, MMP, phosphorylated JAK2 (p-JAK2)/JAK2 and phosphorylated STAT3 (p-STAT3)/STAT3 protein expression decreased in a dose-dependent manner (r=0.998, 0.994, -0.996, -0.981, -0.997, -0.930). Compared with 75 μg/ml kaempferol group, the G0/G1 phase cell proportion and apoptosis rate of cells in IL-6 combined with kaempferol group decreased, while the S phase cell proportion, MMP, p-JAK2/JAK2 and p-STAT3/STAT3 protein expression increased significantly (P<0.05).@*CONCLUSION@#Kaempferol can inhibit KG1a cell proliferation and induce KG1a cell apoptosis, its mechanism may be related to the inhibition of JAK2/STAT3 signal pathway.

Angiotensin converting enzyme 2 alleviates infectious bronchitis virus-induced cellular inflammation by suppressing IL-6/JAK2/STAT3 signaling pathway / 生物工程学报

The goal of this study was to investigate the regulatory effect of angiotensin converting enzyme 2 (ACE2) on cellular inflammation caused by avian infectious bronchitis virus (IBV) and the underlying mechanism of such effect. Vero and DF-1 cells were used as test target to be exposed to recombinant IBV virus (IBV-3ab-Luc). Four different groups were tested: the control group, the infection group[IBV-3ab-Luc, MOI (multiplicity of infection)=1], the ACE2 overexpression group[IBV-3ab Luc+pcDNA3.1(+)-ACE2], and the ACE2-depleted group (IBV-3ab-Luc+siRNA-ACE2). After the cells in the infection group started to show cytopathic indicators, the overall protein and RNA in cell of each group were extracted. real-time quantitative polymerase chain reaction (RT-qPCR) was used to determine the mRNA expression level of the IBV nucleoprotein (IBV-N), glycoprotein 130 (gp130) and cellular interleukin-6 (IL-6). Enzyme linked immunosorbent assay (ELISA) was used to determine the level of IL-6 in cell supernatant. Western blotting was performed to determine the level of ACE2 phosphorylation of janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3). We found that ACE2 was successfully overexpressed and depleted in both Vero and DF-1 cells. Secondly, cytopathic indicators were observed in infected Vero cells including rounding, detaching, clumping, and formation of syncytia. These indicators were alleviated in ACE2 overexpression group but exacerbated when ACE2 was depleted. Thirdly, in the infection group, capering with the control group, the expression level of IBV-N, gp130, IL-6 mRNA and increased significantly (P < 0.05), the IL-6 level was significant or extremely significant elevated in cell supernatant (P < 0.05 or P < 0.01); the expression of ACE2 decreased significantly (P < 0.05); protein phosphorylation level of JAK2 and STAT3 increased significantly (P < 0.05). Fourthly, comparing with the infected group, the level of IBV-N mRNA expression in the ACE2 overexpression group had no notable change (P > 0.05), but the expression of gp130 mRNA, IL-6 level and expression of mRNA were elevated (P < 0.05) and the protein phosphorylation level of JAK2 and STAT3 decreased significantly (P < 0.05). In the ACE2-depleted group, there was no notable change in IBV-N (P > 0.05), but the IL-6 level and expression of mRNA increased significantly (P < 0.05) and the phosphorylation level of JAK2 and STAT3 protein decreased slightly (P > 0.05). The results demonstrated for the first time that ACE2 did not affect the replication of IBV in DF-1 cell, but it did contribute to the prevention of the activation of the IL-6/JAK2/STAT3 signaling pathway, resulting in an alleviation of IBV-induced cellular inflammation in Vero and DF-1 cells.

Signal transducer and activator of transcription 3 and cancer associated fibroblasts jointly generate chemo-resistance and affect prognosis in epithelial ovarian cancer / 中华妇产科杂志

Objective: To investigate the mechanism of signal transducer and activator of transcription 3 (STAT3) and cancer associated fibroblasts (CAF) jointly generate chemo-resistance in epithelial-ovarian cancer and their effect on prognosis. Methods: A total of 119 patients with high-grade ovarian serous cancer who received surgery in Cancer Hospital of Chinese Academy of Medical Sciences from September 2009 to October 2017 were collected. The clinico-pathological data and follow-up data were complete. Multivariate Cox regression model was used to analyze the prognostic factors. Ovarian cancer tissue chips of patients in our hospital were prepared. EnVision two-step method immunohistochemistry was used to detect the protein expression levels of STAT3, the specific markers of CAF activation, fibroblast activating protein (FAP), and type Ⅰ collagen (COL1A1) secreted by CAF. The relationship between the expression of STAT3, FAP, COL1A1 protein and drug resistance and prognosis of ovarian cancer patients was analyzed, and the correlation between the expression of three proteins was analyzed. These results were verified through the gene expression and prognostic information of human ovarian cancer tissues collected in the GSE26712 dataset of gene expression omnibus (GEO) database. Results: (1) Multivariate Cox regression model analysis showed that chemotherapy resistance was an independent risk factor for overall survival (OS) of ovarian cancer (P<0.001). (2) The expression levels of STAT3, FAP, and COL1A1 proteins in chemotherapy resistant patients were significantly higher than those in chemotherapy sensitive patients (all P<0.05). Patients with high expression of STAT3, FAP, and COL1A1 had significantly shorter OS than those with low expression (all P<0.05). According to the human ovarian cancer GSE26712 dataset of GEO database, patients with high expression of STAT3, FAP, and COL1A1 also showed shorter OS than patients with low expression (all P<0.05), the verification results were consistent with the detection results of ovarian cancer patients in our hospital. (3) Correlation analysis showed that the protein level of STAT3 was positively correlated with FAP and COL1A1 in our hospital's ovarian cancer tissue chips (r=0.47, P<0.001; r=0.30, P=0.006), the analysis of GEO database GSE26712 dataset showed that the expression of STAT3 gene and FAP, COL1A1 gene were also significantly positively correlated (r=0.31, P<0.001; r=0.52, P<0.001). Conclusion: STAT3 and CAF could promote chemotherapy resistance of ovarian cancer and lead to poor prognosis.

Morin induces autophagy and apoptosis in hepatocellular carcinoma cells through Akt/mTOR/STAT3 pathway / 中国中药杂志

This study investigated the effect and mechanism of morin in inducing autophagy and apoptosis in hepatocellular carcinoma cells through the protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/signal transducer and activator of transcription protein 3(STAT3) pathway. Human hepatocellular carcinoma SK-HEP-1 cells were stimulated with different concentrations of morin(0, 50, 100, 125, 200, and 250 μmol·L~(-1)). The effect of morin on the viability of SK-HEP-1 cells was detected by Cell Counting Kit-8(CCK-8). The effect of morin on the proliferation and apoptosis of SK-HEP-1 cells was investigated using colony formation assay, flow cytometry, and BeyoClick~(TM) EdU-488 with different concentrations of morin(0, 125, and 250 μmol·L~(-1)). The changes in the autophagy level of cells treated with morin were examined by transmission electron microscopy and autophagy inhibitors. The impact of morin on the expression levels of proteins related to the Akt/mTOR/STAT3 pathway was verified by Western blot. Compared with the control group, the morin groups showed decreased viability of SK-HEP-1 cells in a time-and concentration-dependent manner, increased number of apoptotic cells, up-regulated expression level of apoptosis marker PARP, up-regulated phosphorylation level of apoptosis-regulating protein H2AX, decreased number of positive cells and the colony formation rate, an upward trend of expression levels of autophagy-related proteins LC3-Ⅱ, Atg5, and Atg7, and decreased phosphorylation levels of Akt, mTOR, and STAT3. These results suggest that morin can promote apoptosis, inhibit proliferation, and induce autophagy in hepatocellular carcinoma cells, and its mechanism of action may be related to the Akt/mTOR/STAT3 pathway.

Ethyl Lithospermate Reduces Lipopolysaccharide-Induced Inflammation through Inhibiting NF-κB and STAT3 Pathways in RAW 264.7 Cells and Zebrafish / 中国结合医学杂志

OBJECTIVE@#To explore the anti-inflammatory effects of ethyl lithospermate in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine-derived macrophages and zebrafish, and its underlying mechanisms.@*METHODS@#3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoliumbromide (MTT) assays were performed to investigate the toxicity of ethyl lithospermate at different concentrations (12.5-100 µ mol/L) in RAW 264.7 cells. The cells were stimulated with LPS (100 ng/mL) for 12 h to establish an inflammation model in vitro, the production of pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor α (TNF-α) were assessed by enzyme linked immunosorbent assay (ELISA). Western blot was used to ascertain the protein expressions of signal transducer and activator of transcription 3 (STAT3), nuclear factor kappa B (NF-κB) p65, phospho-STAT3 (p-STAT3, Tyr705), inhibitor of NF-κB (IκB) α, and phospho-I κB α (p-IκB α, Ser32), and confocal imaging was used to identify the nuclear translocation of NF-κB p65 and p-STAT3 (Tyr705). Additionally, the yolk sacs of zebrafish (3 days post fertilization) were injected with 2 nL LPS (0.5 mg/mL) to induce an inflammation model in vivo. Survival analysis, hematoxylin-eosin (HE) staining, observation of neutrophil migration, and quantitative real-time polymerase chain reaction (qRT-PCR) were used to further study the anti-inflammatory effects of ethyl lithospermate and its probable mechanisms in vivo.@*RESULTS@#The non-toxic concentrations of ethyl lithospermate have been found to range from 12.5 to 100 µ mol/L. Ethyl lithospermate inhibited the release of IL-6 and TNF-α(P<0.05 or P<0.01), decreased IκBα degradation and phosphorylation (P<0.05) as well as the nuclear translocation of NF-κB p65 and p-STAT3 (Tyr705) in LPS-induced RAW 264.7 cells (P<0.01). Ethyl lithospermate also decreased inflammatory cells infiltration and neutrophil migration while increasing the survival rate of LPS-stimulated zebrafish (P<0.05 or P<0.01). In addition, ethyl lithospermate also inhibited the mRNA expression levels of of IL-6, TNF-α, IκBα, STAT3, and NF-κB in LPS-stimulated zebrafish (P<0.01).@*CONCLUSION@#Ethyl lithospermate exerts anti-Inflammatory effected by inhibiting the NF-κB and STAT3 signal pathways in RAW 264.7 macrophages and zebrafish.

Identification of Bulbocodin D and C as novel STAT3 inhibitors and their anticancer activities in lung cancer cells / 中国天然药物

Cancer stands as one of the predominant causes of mortality globally, necessitating ongoing efforts to develop innovative therapeutics. Historically, natural products have been foundational in the quest for anticancer agents. Bulbocodin D (BD) and Bulbocodin C (BC), two bibenzyls derived from Pleione bulbocodioides (Franch.) Rolfe, have demonstrated notable in vitro anticancer activity. In human lung cancer A549 cells, the IC50s for BD and BC were 11.63 and 11.71 μmol·L-1, respectively. BD triggered apoptosis, as evidenced by an upsurge in Annexin V-positive cells and elevated protein expression of cleaved-PARP in cancer cells. Furthermore, BD and BC markedly inhibited the migratory and invasive potentials of A549 cells. The altered genes identified through RNA-sequencing analysis were integrated into the CMap dataset, suggesting BD's role as a potential signal transducer and activator of transcription 3 (STAT3) inhibitor. SwissDock and MOE analyses further revealed that both BD and BC exhibited a commendable binding affinity with STAT3. Additionally, a surface plasmon resonance assay confirmed the direct binding affinity between these compounds and STAT3. Notably, treatment with either BD or BC led to a significant reduction in p-STAT3 (Tyr 705) protein levels, regardless of interleukin-6 stimulation in A549 cells. In addition, the extracellular signal-regulated kinase (ERK) was activated after BD or BC treatment. An enhancement in cancer cell mortality was observed upon combined treatment of BD and U0126, the MEK1/2 inhibitor. In conclusion, BD and BC emerge as promising novel STAT3 inhibitors with potential implications in cancer therapy.

Role of biomimetic nanomaterials made from glioma cell- derived extracellular vesicles in targeted delivery of STAT3-siRNA / 中南大学学报(医学版)

OBJECTIVES@#Glioma is the most common primary intracranial tumor and there is still no ideal treatment at present. Gene therapy, as one of the new methods for treating glioma, has attracted attention in recent years. But its application in treating glioma is very limited due to lack of effective delivery vectors. This study aims to investigate the feasibility of biomimetic nanomaterials made from glioma cells-derived extracellular vesicles (EV) for targeted delivery of signal transducers and activators of transcription 3 (STAT3)-small interfering RNA (siRNA) in treating glioma.@*METHODS@#First, U251 glioma cells-derived extracellular vessel (EVU251) was extracted by ultra-centrifugal method. Nanoparticle tracking analysis was used to characterize the particle size distribution, the transmission electron microscope was used to analyze the morphology, and Western blotting was used to verify the expression of srface characteristic protein. The homing ability was verified by cell uptake assay after labeling EVU251 with membrane dye kit PKH67; the EVU251 contents were removed by a low permeability method and then EVMU251 was prepared through a microporous membrane. Finally, the biomimetic nanomaterials EVMU251@STAT3-siRNA were prepared by loading STAT3-SiRNA with electro-dyeing method. The real-time quantitative PCR was used to quantify the successful encapsulation of siRNA, and the encapsulation and drug loading rate was calculated; then Cy5-labeled siRNA was used to evaluate the ability of biomimetic nanomaterials (EVMU251@CY5-siRNA) to target U251 cells. Lysosomal escape ability of the biomimetic nanomaterial was evaluated by lysosomal dye lyso-tracker green. At last, the ability of EVMU251@STAT3-siRNA to knock down STAT3 gene and selective killing of U251 cells was detected by cell experiments in vitro.@*RESULTS@#The size of EVU251 ranged from 50 nm to 200 nm with a natural disc shape. The expression of extracellular vesicle marker proteins could be detected on the membrane of EVU251. The cell uptake assay demonstrated that it had homing ability to target U251 cells. After EVU251 was prepared as EVMU251@STAT3-siRNA, the particle size was (177.9±5.0) nm, the siRNA loading rate was (33.5±2.2)% and the drug loading rate was (3.24±0.21)%. The biomimetic nanomaterial EVMU251@STAT3-siRNA still had the ability to target U251 cells and successfully deliver siRNA to the cytoplasm without lysosomal degradation. The EVMU251@STAT3-siRNA can effectively knock down the expression of STAT3 gene and produce selective killing ability in U251 cells.@*CONCLUSIONS@#The biomimetic nanomaterials EVMU251@STAT3-siRNA made from glioma U251 cells-derived extracellular vesicles can knock down STAT3 gene of U251 cells and produce selective killing effect, which can provide a new idea for the treatment of glioma.

YAP regulates intestinal epithelial cell proliferation through activation of STAT3 in DSS-induced colitis and associated cancer / 中南大学学报(医学版)

OBJECTIVES@#Ulcerative colitis (UC) is a chronic, relapsing inflammation of the colon. Impaired epithelial repair is an important biological features of UC. Accelerating intestinal epithelial repair to achieve endoscopic mucosal healing has become a key goal in UC. Yes-associated protein (YAP) is a key transcriptional coactivator that regulates organ size, tissue growth and tumorigenesis. Growing studies have focused on the role of YAP in intestinal epithelial regeneration. This study explore the molecular mechanism for the role YAP in modulating colonic epithelial proliferation, repair, and the development of colitis associated cancer.@*METHODS@#We constructed the acute colitis mouse model through successive 5 days of 3% dextran sulfate sodium salt (DSS) induction. Then YAP-overexpressed mouse model was constructed by intraperitoneal injection the YAP overexpressed and negative control lentivirus into DSS mice. On the 5th day of DSS induction and the 5th day of normal drinking water after removing DSS (5+5 d), the mice were killed by spinal dislocation. The colon was taken to measure the length, and the bowel 1-2 cm near the anal canal was selected for immunohistochemical and Western blotting. We used YAP over-expressed colonic epithelial cells and small interfering signal transducer and activator of transcription 3 (STAT3) RNA to probe the regulation of YAP on STAT3, using cell counting kit-8 and scratch assays to explore the role of YAP on colonic epithelial cell proliferation. Finally, we conducted co-immunoprecipitation to test the relationship between YAP and STAT3.@*RESULTS@#After DSS treatment, the expression of YAP was dramatically diminished in crypts. Compared with the empty control mice, overexpression of YAP drastically accelerated epithelial regeneration after DSS induced colitis, presenting with more intact of structural integrity in intestinal epithelium and a reduction in the number of inflammatory cells in the mucosa. Further Western blotting, functional experiment and co-immunoprecipitation analyses showed that the expression of YAP in nucleus was significantly increased by 2 h post DSS cessation, accompanied with up-regulated total protein levels of STAT3 and phosphorylated-STAT3 (p-STAT3). Overexpression of YAP enhanced the expression of STAT3, p-STAT3, and their transcriptional targets including c-Myc and Cyclin D1. In addition, it promoted the proliferation and the "wound healing" of colonic cells. However, these effects were reversed when silencing STAT3 on YAP-overexpressed FHC cells. Moreover, protein immunoprecipitation indicated that YAP could directly interact with STAT3 in the nucleus, up-regulatvng the expressvon of STAT3. Finally, during the process of CAC, overexpression of YAP mutant caused the down-regulated expression of STAT3 and inhibited the development and progress of CAC.@*CONCLUSIONS@#YAP activates STAT3 signaling in regulation of epithelial cell proliferation and promotes mucosal regeneration after DSS induced colitis, which may serve as a potential therapeutic target in UC. However, persistent and excessive YAP activation may promote CAC development.

Triptolide inhibits inflammatory response and migration of fibroblast like synovial cells in rheumatoid arthritis through the circRNA 0003353/JAK2/STAT3 signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effect of triptolide (TPL) on inflammatory response and migration of fibroblast like synovial cells (FLS) in rheumatoid arthritis (RA-FLS) and the mechanism of circular noncoding RNA (circRNA) 0003353 for mediating this effect.@*METHODS@#We collected peripheral blood mononuclear cells (PBMCs) and serum samples from 50 hospitalized RA patients and 30 healthy individuals for detecting the expression of circRNA 0003353, immune and inflammatory indexes (ESR, CRP, RF, anti-CCP, IgA, IgG, IgM, C3, and C4) and DAS28 score. Cultured RA-FLS was treated with 10 ng/mL TPL and transfected with a circRNA 0003353 overexpression plasmid, and cell counting kit-8 (CCK-8) assay and Transwell assay were used to detect the changes in the viability and migration of the cells. Enzyme-linked immunosorbent assay (ELISA) was used to examine the cytokines IL-4, IL-6, and IL-17, and real-time fluorescence quantitative PCR (RT-qPCR) was performed to detect the expression of circRNA 003353; Western blotting was used to detect the expressions of p-JAK2, pSTAT3, JAK2 and STAT3 proteins in the treated cells.@*RESULTS@#The expression of circRNA 0003353 was significantly increased in PBMCs from RA patients and showed a good performance in assisting the diagnosis of RA (AUC=90.5%, P < 0.001, 95% CI: 0.83-0.98). CircRNA 0003353 expression was positively correlated with ESR, RF and DAS28 (P < 0.05). Treatment with TPL significantly decreased the expression of circRNA 0003353, suppressed the viability and migration ability, decreased the expressions of IL-6 and IL-17, and increased the expression IL-4 in cultured RA-FLS in a time-dependent manner (P < 0.01). TNF-α stimulation of RA-FLS significantly increased the ratios of p-JAK2/JAK2 and p-STAT3/STAT3, which were obviously lowered by TPL treatment (P < 0.01). TPL-treated RA-FLS overexpressing circRNA 0003353 showed significantly increased cell viability and migration ability with decreased IL-4 expression and increased IL-6 and IL-17 expressions and ratios of p-JAK2/ JAK2 and p-STAT3/STAT3 (P < 0.01).@*CONCLUSION@#The expression of circRNA 0003353 is increased in PBMCs in RA patients and in RA-FLS. TPL treatment can regulate JAK2/STAT3 signal pathway and inhibit the inflammatory response and migration of RA-FLS through circRNA 0003353.

The IL-6/STAT3 signaling pathway mediated by radiotherapy regulates the expression of PD-L1 in esophageal cancer cells / 中华肿瘤杂志

Objective: To explore the possible mechanism of radiotherapy regulating the expression of PD-L1 in esophageal carcinoma. Methods: Three esophageal cancer cell lines (Eca109, Kyse150, TE1) were irradiated with different doses of X-rays, and 6 Gy+ AG490 group was set. The mRNA expression of PD-L1 was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The protein expressions of PD-L1, STAT3, p-STAT3 were detected by western blotting and the protein level of IL-6 was detected by ELISA. Results: The mRNA expressions of PD-L1 in Eca109, Kyse150 and TE1 were 2.86±0.30, 960.01±21.27 and 106.78±6.67, higher than 1.07±0.15 in normal esophageal cell line HET-1A (P<0.01). The protein expressions of PD-L1 in Eca109, Kyse150 and TE1 were 0.091±0.036, 1.533±0.079 and 0.914±0.035, higher than 0.063±0.01 in normal esophageal cell line HET-1A (P<0.01). After 48 hours of 6 Gy irradiation, the protein expression levels of PD-L1 in Eca109, Kyse150 and TE1 were 0.135±0.007, 1.66±0.06 and 1.32±0.06, higher than 0.09±0.01, 1.21±0.05 and 0.93±0.03 of the 0 Gy group (P<0.01), while the protein expression levels of p-STAT3 in Eca109, Kyse150 and TE1 were 1.44±0.26, 0.75±0.04 and 1.92±0.17, higher than 0.18±0.05, 0.48±0.02 and 0.36±0.06 of the 0 Gy group (P<0.01). IL-6 protein expression increased significantly after different doses of irradiation (P<0.01). After the IL-6/STAT3 signaling pathway was blocked by the specific inhibitor AG490, the expressions of PD-L1 of Eca109, Kyse150 and TE1 in the 6 Gy+ AG490 groups were 0.11±0.03, 1.07±0.08 and 0.96±0.11, without significant differences of 0.09±0.01, 0.96±0.05 and 0.85±0.09 of the 0 Gy group (P>0.05), while the protein expressions of p-STAT3 were 0.76±0.11, 0.59±0.06 and 0.96±0.12, without significant differences of 0.67±0.08, 0.54±0.06 and 0.84±0.11 of the 0 Gy group (P>0.05). Conclusion: Radiotherapy may regulate the expression of PD-L1 in esophageal cancer cells through IL-6 / STAT3 signaling pathway.

Chaihu Guizhi Decoction plus or minus formula combined with capecitabine inhibits IL-6/STAT3 signaling to suppress triple-negative breast cancer xenografts in nude mice / 南方医科大学学报

OBJECTIVE@#To investigate the effect of Chaihu Guizhi Decoction (CHGZD) combined with capecitabine on growth and apoptosis of subcutaneous triple-negative breast cancer xenografts in nude mice and explore the possible mechanism.@*METHODS@#Nude mouse models bearing subcutaneous triple-negative breast cancer xenografts were randomized into 6 groups (n=10) for treatment with distilled water (model group), low (10.62 g/kg), medium (21.23 g/kg) and high (42.46 g/kg) doses of CHGZD, capecitabine (0.2 mg/kg), or the combination of CHGZD (42.46 g/kg) and capecitabine (0.2 mg/k) once daily for 21 consecutive days. The general condition of mice was observed, and after 21-day treatments, the tumors were dissected for measurement of tumor volume and weight and histopathological examination with HE staining. Serum IL-6 levels of the mice were determined with enzyme-linked immunosorbent assay (ELISA), and the expression levels of IL-6, STAT3, p-STAT3, Bax, Bcl-2 and cyclin D1 in the tumor tissues were detected using real-time PCR and Western blotting.@*RESULTS@#Compared with those in the model group, the tumor-bearing mice receiving treatments with CHGZD showed significantly increased food intake with good general condition, sensitive responses, increased body weight, and lower tumor mass (P < 0.01). Compared with capecitabine treatment alone, treatment with CHGZD alone at the medium and high doses and the combined treatment all resulted in significantly higher tumor inhibition rates (P < 0.01), induced obvious tumor tissue degeneration and reduced the tumor cell density. Treatments with CHGZD, both alone and in combination with capecitabine, significantly decreased serum IL-6 level, lowered the mRNA expression levels of IL-6 and STAT3, the protein expressions of IL-6, STAT3 and P-STAT3 (P < 0.05), and the mRNA and protein expressions of Bcl-2 and cyclin D1 (P < 0.05), and increased the mRNA and protein expressions of Bax in the tumor tissues (P < 0.05).@*CONCLUSION@#CHGZD combined with capecitabine can significantly inhibit tumor growth in nude mice bearing triple-negative breast cancer xenografts, the mechanism of which may involve the inhibition of IL-6/STAT3 signaling pathway and regulation of Bax, Bcl-2 and cyclin D1 expressions to suppress tumor cell proliferation and differentiation and induce cell apoptosis.

Gastric cancer-derived mesenchymal stem cells regulate the M2 polarization of macrophages within gastric cancer microenvironment via JAK2/STAT3 signaling pathway / 中华肿瘤杂志

Objective: To investigate the role and mechanism of tumor-derived mesenchymal stem cells in regulating the M2 polarization of macrophages within gastric cancer microenvironment. Methods: Gastric cancer tissues and the adjacent non-cancerous tissues were collected from patients underwent gastric cancer resection in the First People's Hospital of Lianyungang during 2018. In our study, THP-1-differentiated macrophages were co-cultured with gastric cancer-derived mesenchymal stem cells (GC-MSCs). Then, the M2 subtype-related gene, the markers expressed on cell surface and the cytokine profile were analyzed by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), flow cytometry and Luminex liquid chip, respectively. The key cytokines mediating the inducing effect of GC-MSCs on macrophage polarization into the M2 subtype were detected and screened by Luminex liquid chip, which were further confirmed by the neutralizing antibody test. The expressions of macrophage proteins involved in M2 polarization-related signaling pathways under the different co-culture conditions of GC-MSCs were detected by western blot. Results: In Mac+ GC-MSC-culture medium (CM) group, the expression levels of Ym-1 and Fizz-1 (1.53±0.32 and 13.22±1.05, respectively), which are markers for M2 subtype, were both significantly higher than those of Mac group (1.00±0.05 and 1.21±0.38, respectively, P<0.05). The level of iNOS in Mac+ GC-MSC-CM group (0.60±0.41) was significantly lower than that of Mac group (1.06±0.38, P=0.023). In Mac+ GC-MSC-Transwell (TW) group, the expression levels of Ym-1 and Fizz-1 (1.47±0.09 and 13.16±2.77, respectively) were both significantly higher than those of Mac group (1.00±0.05 and 1.21±0.38, respectively, P<0.05). The level of iNOS in Mac+ GC-MSC-CM group (0.56±0.03) was significantly lower than that of Mac group (1.06±0.38, P=0.026). The ratios of CD163(+) /CD204(+) cells in Mac+ GC-MSC-CM and Mac+ GC-MSC-TW groups (3.80% and 4.40%, respectively) were both remarkably higher than that of Mac group (0.60%, P<0.05). The expression levels of IL-10, IL-6, MCP-1 and VEGF in Mac+ GC-MSC-CM group were (592.60±87.52), (1 346.80±64.70), (11 256.00±29.03) and (1 463.90±66.67) pg/ml, respectively, which were significantly higher than those of Mac group [(41.03±2.59), (17.35±1.79), (5 213.30±523.71) and (267.12±12.06) pg/ml, respectively, P<0.05]. The levels of TNF-α, IP-10, RANTES and MIP-1α were (95.57±9.34), (410.48±40.68), (6 967.30±1.29) and (1 538.70±283.04) pg/ml, which were significantly lower than those of Mac group [(138.01±24.31, (1 298.60±310.50), (14 631.00±4.21) and (6 633.20±1.47) pg/ml, respectively, P<0.05]. The levels of IL-6 and IL-8 in GC-MSCs [(11 185.02±2.82) and (12 718.03±370.17) pg/ml, respectively] were both strikingly higher than those of MSCs from adjacent non-cancerous gastric cancer tissues [(270.71±59.38) and (106.04±32.84) pg/ml, repectively, P<0.05]. The ratios of CD86(+) cells in Mac+ IL-6-blocked-GC-MSC-CM and Mac+ IL-8-blocked-GC-MSC-CM groups (28.80% and 31.40%, respectively) were both higher than that of Mac+ GC-MSC-CM group (24.70%). Compared to Mac+ GC-MSC-CM group (13.70%), the ratios of CD204(+) cells in Mac+ IL-6-blocked-GC-MSC-CM and Mac+ IL-8-blocked-GC-MSC-CM groups (9.90% and 8.70%, separately) were reduced. The expression levels of p-JAK2 and p-STAT3, which are proteins of macrophage M2 polarization-related signaling pathway, in Mac+ GC-MSC-CM group (0.86±0.01 and 1.08±0.01, respectively) were significantly higher than those of Mac group (0.50±0.01 and 0.82±0.01, respectively, P<0.05). The expression levels of p-JAK2 in Mac+ IL-6-blocked-GC-MSC-CM group (0.47±0.02) were significantly lower those that of Mac+ GC-MSC-CM group (0.86±0.01, P<0.05). The expression levels of p-JAK2 and p-STAT3 in Mac+ IL-8-blocked-GC-MSC-CM group (0.50±0.01 and 0.85±0.01, respectively) were both significantly lower than those of Mac+ GC-MSC-CM group (0.86±0.01 and 1.08±0.01, P<0.05). The expression levels of p-JAK2 and p-STAT3 in Mac+ IL-6/IL-8-blocked-GC-MSC-CM group (0.37±0.01 and 0.65±0.01, respectively) were both significantly lower than those of Mac+ GC-MSC-CM group (0.86±0.01 and 1.08±0.01, P<0.05). Conclusion: GC-MSCs promote the activation of JAK2/STAT3 signaling pathway in macrophages via high secretions of IL-6 and IL-8, which subsequently induce the macrophage polarization into a pro-tumor M2 subtype within gastric cancer microenvironment.

Kang-Ai Injection Inhibits Gastric Cancer Cells Proliferation through IL-6/STAT3 Pathway / 中国结合医学杂志

OBJECTIVE@#To explore the mechanisms underlying the proliferative inhibition of Chinese herbal medicine Kang-Ai injection (KAI) in gastric cancer cells.@*METHODS@#Gastric cancer cell lines MGC803 and BGC823 were treated by 0, 0.3%, 1%, 3% and 10% KAI for 24, 48 and 72 h, respectively. The cell proliferation was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The apoptosis and cell cycle were evaluated by flow cytometry. Interleukin (IL)-6 mRNA and protein expression levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immune sorbent assay (ELISA), respectively. The protein expression levels of cyclin A, cyclin E, cyclin B1, cyclin D1, p21, retinoblastoma (RB), protein kinase B (AKT), extracellular regulated protein kinases (ERK), signal transducer and activator of transcription (STAT) 1 and STAT3 were detected by Western blot.@*RESULTS@#KAI inhibited the proliferation of MGC803 and BGC823 gastric cancer cells in dose- and time-dependent manner. After treated with KAI for 48 h, the proportion of G1 phase was increased, expression level of cyclin D1 and phosphorylation-RB were down-regulated, whereas the expression of p21 was up-regulated (all P<0.01). Furthermore, 48-h treatment with KAI decreased the phosphorylation level of STAT3, inhibited the mRNA and protein expressions of IL-6 (all P<0.01). IL-6 at dose of 10 ng/mL significantly attenuated the proliferative effect of both 3% and 10% KAI, and recovered KAI-inhibited STAT3 phosphorylation and cyclin D1 expression level (all P<0.01).@*CONCLUSION@#KAI exerted an anti-proliferative function by inhibiting IL-6/STAT3 signaling pathway followed by the induction of G1 phase arrest in gastric cancer cells.

Vitamina D, miR-21 y marcadores de apoptosis en pacientes con diabetes tipo I / Vitamin D, miR-21 and apoptosis markers in patients with type 1 diabetes

La diabetes Tipo 1 (DT1) es una compleja enfermedad autoinmune con una etiología aún desconocida. La vitamina D ha sido ampliamente estudiada debido a su potencial terapéutico en los potenciales nuevos casos de DT1. Por otra parte, los microARNs (miRs) han sido propuestos como posibles biomarcadores en diversos procesos biológicos como en la apoptosis e inflamación. El objetivo de este estudio fue evaluar el efecto de la suplementación con vitamina D sobre el perfil de expresión del miR-21 y marcadores de apoptosis tales como: BCL2, STAT3, TIPE2 y DAXX, en células mononucleares periféricas provenientes de pacientes con DT1 y sujetos controles. RESULTADOS: El perfil de expresión de miR-21 se encontró disminuido en los pacientes con DT1 en comparación con los controles. La expresión relativa de BCL2 se encontró aumentada en controles al comparar con pacientes DT1 en todas las condiciones experimentales. La expresión relativa de DAXX mostró un perfil de expresión diferencial al comparar pacientes con DT1 versus controles (p=0.006). CONCLUSIÓN: El estímulo con vitamina D parece tener un posible efecto regulador sobre los genes BCL2 y DAXX.

Type 1 diabetes (T1D) is a complex chronic autoimmune disease. Vitamin D has been one of the most studied therapeutic potential outbreaks related to T1D. Specific miRNAs have been proposed as potential biomarkers in several biological processes as apoptosis and inflammation. The aim of this study was to evaluate the effect of vitamin D on the expression profiles of miR-21 and apoptotic markers BCL2, STAT3, TIPE2 and DAXX, in PBMCs from T1D patients and control subjects. RESULTS: miR-21 expression was increased in controls regarding T1D patients. BCL2 was increased in controls compared to T1D patients in all experimental conditions. DAXX showed different expression patterns between T1D patients and controls (p=0.006). CONCLUSION: Vitamin D showed a possible regulation effect on apoptosis markers mainly through the regulation of BCL2 and DAXX

Physalin B reduces Aβ secretion through down-regulation of BACE1 expression by activating FoxO1 and inhibiting STAT3 phosphorylation / 中国天然药物

Physalin B (PB), one of the major active steroidal constituents of Solanaceae Physalis plants, has a wide variety of biological activities. We found that PB significantly down-regulated β-amyloid (Aβ) secretion in N2a/APPsw cells. However, the underlying mechanisms are not well understood. In the current study, we investigated the changes in key enzymes involved in β-amyloid precursor protein (APP) metabolism and other APP metabolites by treating N2a/APPsw cells with PB at different concentrations. The results indicated that PB reduced Aβ secretion, which was caused by down-regulation of β-secretase (BACE1) expression, as indicated at both the protein and mRNA levels. Further research revealed that PB regulated BACE1 expression by inducing the activation of forkhead box O1 (FoxO1) and inhibiting the phosphorylation of signal transducer and activator of transcription 3 (STAT3). In addition, the effect of PB on BACE1 expression and Aβ secretion was reversed by treatment with FoxO1 siRNA and STAT3 antagonist S3I-201. In conclusion, these data demonstrated that PB can effectively down-regulate the expression of BACE1 to reduce Aβsecretion by activating the expression of FoxO1 and inhibiting the phosphorylation of STAT3.

Research progress on proteasome subunits in regulating occurrence and development of hepatocellular carcinoma / 浙江大学学报·医学版

Proteasome is the eukaryotic organelle responsible for degradation of short-lived proteins and involved in maintaining cellular protein homeostasis. It has been reported that during the occurrence and development of hepatocellular carcinoma (HCC), the regulatory particle subunits of proteasome regulate a series of tumor-related proteins, and proliferation, survival-associated signaling molecules, including PTEN gene, P53, Bcl-2, Bcl-2 interacting mediator of cell death (Bim), cyclin-dependent kinase 4(CDK4), transforming growth factor β receptor (TGFBR), E2F1, growth factor receptor-bound protein 2 (GRB2) . Meanwhile, these subunits regulate some tumor-associated pathway protein, such as signal transducer and activator of transcription 3 (STAT3) and protein kinase B (AKT), inducing their malfunction to promote the occurrence, proliferation, invasion and metastasis of HCC. The core particle subunits are more to perform the degradation of HCC-related proteins, so inhibitors targeting the core particle show a good anti-tumor effect. This review summarizes the current research progress on the regulation and mechanism of proteasome subunits in promoting the occurrence and development .

Curcumin mediates IL-6/STAT3 signaling pathway to repair intestinal mucosal injury induced by 5-FU chemotherapy for colon cancer / 中国中药杂志

This study aims to investigate the potential mechanism of curcumin in mediating interleukin-6(IL-6)/signal transducer and activator of transcription 3(STAT3) signaling pathway to repair intestinal mucosal injury induced by 5-fluorouracil(5-FU) chemotherapy for colon cancer. SD rats were intraperitoneally injected with 60 mg·kg~(-1)·d~(-1) 5-FU for 4 days to establish a model of intestinal mucosal injury. Then the rats were randomly divided into model group(equal volume of normal saline), curcumin low, medium and high dose groups(50, 100, 200 mg·kg~(-1)), and normal SD rats were used as control group(equal volume of normal saline). Each group received gavage administration for 4 consecutive days, and the changes of body weight and feces were recorded every day. After administration, blood was collected from the heart, and jejunum tissues were collected. The levels of serum interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) were detected by ELISA, and at the same time, the concentration of Evans blue(EB) in jejunum was measured. Hematoxylin-eosin(HE) staining was used to observe the pathological state of jejunum, and the length of jejunum villi and the depth of crypt were measured. The positive expression levels of claudin, occludin and ZO-1 were detected by immunohistochemistry. Western blot was used to detect the protein expression of IL-6, p-STAT3, E-cadherin, vimentin and N-cadherin in jejunum tissues. The results showed that, curcumin significantly increased body weight and fecal weight(P<0.05 or P<0.01), decreased fecal score, EB concentration, IL-1β and TNF-α levels(P<0.05 or P<0.01) in rats. In addition, curcumin maintained the integrity of mucosal surface and villi structure of jejunum to a large extent, and reduced pathological changes in a dose-dependent manner. Meanwhile, curcumin could increase the positive expression of occludin, claudin and ZO-1(P<0.05 or P<0.01), repair intestinal barrier function, downregulate the protein expression of IL-6, p-STAT3, vimentin and N-cadherin in jejunum tissues(P<0.05 or P<0.01), and upregulate the protein expression of E-cadherin(P<0.05). Therefore, curcumin could repair the intestinal mucosal injury induced by 5-FU chemotherapy for colon cancer, and the mechanism may be related to the inhibition of IL-6/STAT3 signal and the inhibition of epithelial-mesenchymal transition(EMT) process.

Parathyroid hormone increases alveolar bone homoeostasis during orthodontic tooth movement in rats with periodontitis via crosstalk between STAT3 and β-catenin / 国际口腔科学杂志·英文版

Periodontitis patients are at risk of alveolar bone loss during orthodontic treatment. The aim of this study was to investigate whether intermittent parathyroid hormone (1-34) treatment (iPTH) could reduce alveolar bone loss during orthodontic tooth movement (OTM) in individuals with periodontitis and the underlying mechanism. A rat model of OTM in the context of periodontitis was established and alveolar bone loss was observed. The control, iPTH and iPTH + stattic groups received injections of vehicle, PTH and vehicle, or PTH and the signal transducer and activator of transcription 3 (STAT3) inhibitor stattic, respectively. iPTH prevented alveolar bone loss by enhancing osteogenesis and suppressing bone resorption in the alveolar bone during OTM in rats with periodontitis. This effect of iPTH was along with STAT3 activation and reduced by a local injection of stattic. iPTH promoted osteoblastic differentiation and might further regulate the Wnt/β-catenin pathway in a STAT3-dependent manner. The findings of this study suggest that iPTH might reduce alveolar bone loss during OTM in rats with periodontitis through STAT3/β-catenin crosstalk.

CXCL8(3-72) K11R/G31P protects against sepsis-induced acute kidney injury via NF-κB and JAK2/STAT3 pathway

BACKGROUND: Acute kidney injury (AKI), which is mainly caused by sepsis, has high morbidity and mortality rates. CXCL8(3-72) K11R/G31P (G31P) can exert therapeutic effect on inflammatory diseases and malignancies. We aimed to investigate the effect and mechanism of G31P on septic AKI. METHODS: An AKI mouse model was established, and kidney injury was assessed by histological analysis. The contents of serum creatinine (SCr) and blood urea nitrogen (BUN) were measured by commercial kits, whereas neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) were detected by enzyme-linked immunosorbent assay (ELISA) kits. The expressions of CXCL8 in serum and kidney tissues were determined using ELISA and immunohistochemical analysis, respectively. Apoptosis rate of renal tissue was detected by terminal deoxynucleotidyl transfer-mediated dUTP nick end labeling (TUNEL) analysis. The expressions of inflammatory cytokines were measured by quantitative real-time PCR and Western blot, respectively. The apoptosis-related proteins, JAK2, STAT3, NF-κB and IκB were determined by Western blot. RESULTS: G31P could reduce the levels of SCr, BUN, HGAL and KIM-1 and inhibit the renal tissue injury in AKI mice. G31P was also found to suppress the serum and nephric CXCL8 expressions and attenuated the apoptosis rate. The levels of inflammatory cytokines, pro-apoptotic proteins were decreased, while the anti-apoptotic proteins were increased by G31P in AKI mice. G31P also inhibited the activation of JAK2, STAT3 and NF-κB in AKI mice. CONCLUSION: These results suggest that G31P could protect renal function and attenuate the septic AKI. Our findings provide a potential target for the treatment of AKI.

Rhein alleviates renal interstitial fibrosis by inhibiting tubular cell apoptosis in rats

BACKGROUND: Ureteral obstruction causes injury of the renal tissues and can irreversibly progress to renal fibrosis, with atrophy and apoptosis of tubular cells. The goal of the current study was to examine the effects of rhein on the apoptosis o renal tubular cells as well as renal fibrosis using a rodent model of unilateral ureteral obstruction (UUO). METHODS: UUO was induced through ureteral ligation, then animals received treatments with rhein or vehicle. The control rats only received sham operation. The renal tissue was harvested 1 week after surgery for assessment of kidney fibrosis. RESULTS: The expressions of collagen I and α-smooth muscle actin (α-SMA), as well as the severity of renal tubular apoptosis and fibrosis were time-dependently increased following UUO. Treatments with rhein partially inhibited such responses. Renal interstitial fibrosis was associated with STAT3 (signal transducer and activator of transcription 3) phosphorylation as well as altered expressions of Bax and Bcl2, both apoptosis-related proteins. Treatment with rhein also partly blocked these responses. CONCLUSION: These findings demonstrated that rhein mitigated apoptosis of renal tubular cell as well as renal fibrosis in a UUO rodent model. This curative effect is likely mediated via suppression of STAT3 phosphorylation.