Large granular lymphocytic leukemia (LGLL) is a rare lymphoproliferative disorder of clonal expansion of cytotoxic T- or NK-cells in blood and bone marrow, and often associated with autoimmune disorders. According to the current WHO classification of the hematopoietic and lymphoid tissue tumors, the clonal LGL expansions are further classified as T-cell large granular lymphocytic leukemia (T-LGLL), chronic lymphoproliferative disorders of NK cells (CLPD-NK) and aggressive NK cell leukemia. Since there is a general lack of awareness of this disease, some patients may be misdiagnosed or some cases may be missed when diagnosis was done. At present, the pathogenesis of LGLL remains incomplete and unclear, and the therapeutic effects are unsatisfactory. For this reason, it is necessary to find prognostic marks and therapeutic targets of this disease. The constitutive activation of JAK/STAT pathway has been claimed to be involved in the development of LGLL. Recently, the somatic mutations in the SH2 domain of STAT3 in LGLL are frequently observed, which lead to the activation of JAK/STAT pathway. STAT3 is the first molecular markers that are highly specific for LGLL, and STAT3 mutations have been rarely detected in other tumor types studied, thus the STAT3 mutations can be used as molecular markers for LGLL diagnosis and can provide a novel therapeutic target for patients with LGLL.
Humans ; Janus Kinases ; genetics ; metabolism ; Leukemia, Large Granular Lymphocytic ; genetics ; metabolism ; Mutation ; STAT3 Transcription Factor ; genetics ; metabolism ; Signal Transduction

OBJECTIVE: To show that Stat3 played a key role in the G1 to S phase transition in laryngocarcinoma cells. METHOD: Human laryngocarcinoma cell lines Hep-2 were transfected with Stat3 antisense oligonucleotide mediated by liposome, MTT assay was used to measure the proliferation, flow cytometry was applied to analyze the cell cycle, and the expressions of Stat3, phosphorylation specific Stat3 (tyrosine705), CyclinD1, Cyclin E, CDK2, CDK4, CDK6, p21 and p27 were detected by western blot. RESULT: Hep-2 laryngocarcinoma cell lines expressed constitutively activated Stat3. Antisense oligonucleotide which directed blocked up the translation site resulted in growth inhibition, downregulation of Stat3, p-Stat3, Cyclins and CDKs, and upregulation of p21 and p27. CONCLUSION Our findings suggested that Stat3 played an important role in the G1 to S phase transition in laryngocarcinoma cells, Stat3 orchestrated cell cycle by regulating the balance between CDK/Cyclin complex and CKI.
Cell Line, Tumor ; G1 Phase ; Humans ; Laryngeal Neoplasms ; metabolism ; pathology ; S Phase ; STAT3 Transcription Factor ; genetics ; metabolism ; Signal Transduction ; Transfection

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.
Humans ; RNA, Small Interfering/genetics* ; Biomimetics ; Cell Line, Tumor ; Glioma/therapy* ; Nanostructures ; Cell Proliferation ; STAT3 Transcription Factor/metabolism*

The pathogenesis of psoriasis recently made great advancement due to the introduction of transgenic mouse model. K14-VEGF transgenic mouse showed many of the cellular and molecular features of psoriasis, including angiogenesis in dermis, altered epidermal proliferation and differentiation. Psoriasis of early onset and severe disease showed significantly increased frequency of the +405CC genotype and the C allele. Transgenic mice with keratinocytes expressing active Stat3 (K5. Stat3C mice) developed a skin phenotype closely resembling psoriasis. Stat 3 may link activated keratinocytes and immunocytes required for development of psoriasis. More recently, a novel mouse model with epidermal specific double-knockout of the c-Jun and JunB genes showed developments of psoriasis-like skin phenotype and arthritic lesions. All these data provided more profound understanding in pathogenesis and therapy of psoriasis.
Animals ; Disease Models, Animal ; Humans ; Keratinocytes ; metabolism ; pathology ; Mice ; Mice, Knockout ; Mice, Transgenic ; Psoriasis ; etiology ; genetics ; pathology ; STAT3 Transcription Factor ; genetics ; metabolism ; Vascular Endothelial Growth Factors ; genetics ; metabolism

This study was aimed to investigate the activation of P38MAPK/STAT3 and expression of telomerase reverse transcriptase during sodium nitroprusside (SNP) inducing apoptosis of human leukemia cell line K562 and to explore the molecular mechanisms of SNP-inducing apoptosis in K562 cells. The K562 cell were treated with different concentrations of SNP and were cultured for different time. Cell apoptosis was analysed by cell morphology, DNA agarose gel electrophoresis, DNA content, and Annexin-V/PI labeling method. The TdT-mediated dUTP nick end labeling (TUNEL) assay was used to quantitate the in situ cell apoptosis. The expressions of phosphorylated p38MAPK or STAT3 were analysed by flow cytometry, while the expression of hTERT mRNA in transcriptional level was measured by fluorescence quantitative RT-PCR. The results showed that SNP inhibited K562 cell growth. The K562 cell apoptosis was confirmed by typical cell morphology and DNA fragment, peak of sub-G1 phase, TUNEL and Annexin-V/PI labeling. A majority of K562 cells were arrested in G0/G1 phase. After treatment with SNP at 0.5-3.0 mmol/L, the expression of phosphorylated-P38MAPK and phosphorylated-STAT3 increased first and decreased afterwards. Incubation of K562 cell with SNP (2 mmol/L) could increase the expression of phosphorylated-P38MAPK and phosphorylated-STAT3 at 12 hours and 24 hours respectively, and down-regulated at 72 hours and 48 hours. SNP could decrease the expression of hTERT-mRNA in time-and dose-dependent manner. It is concluded that SNP can significantly induce K562 cells apoptosis, its mechanism may be related to the activation of P38MAPK and suppression of phosphorylated-STAT3 and hTRET-mRNA.
Apoptosis ; drug effects ; Humans ; K562 Cells ; Nitroprusside ; pharmacology ; RNA, Messenger ; biosynthesis ; genetics ; STAT3 Transcription Factor ; genetics ; metabolism ; Telomerase ; biosynthesis ; genetics ; p38 Mitogen-Activated Protein Kinases ; genetics ; metabolism

OBJECTIVETo study the effects of pSilencer 1.0-U6-siRNA-STAT3 on the growth of PC3 and LNCaP cells.

METHODSThree pairs of DNA template coding siRNA were synthesized against STAT3 to reconstruct pSilencer 1.0-U6-STAT3-siRNA, which was transfected into PC3 and LNCaP cells. The STAT3 expression in PC3 cells and LNCaP were transfected with pSilencer 1.0-U6-siRNA-STAT3, and it was detected by Western blot and Northern blot. MTT and FCM were used to observe the growth-inhibiting ratio and apoptosis in PC3 cells.

RESULTSWestern blot and Northern blot analyses demonstrated that pSilencer 1.0-U6-siRNA-STAT3 could significantly inhibit the expression of STAT3 in PC3 and LNCaP cells; MIT and FCM results showed that it could suppress the growth of PC3 cells and LNCaP and induce apoptosis of PC3 cells in vitro.

CONCLUSIONPSilencer 1.0-U6-siRNA-STAT3 could significantly inhibit STAT3 expression, suppress the growth of PC3 and LNCaP cells and induce the apoptosis of PC3 cells.

Apoptosis ; Cell Line, Tumor ; Humans ; Male ; Plasmids ; Prostatic Neoplasms ; metabolism ; pathology ; RNA, Messenger ; genetics ; RNA, Small Interfering ; STAT3 Transcription Factor ; biosynthesis ; genetics ; Transcription, Genetic

Animals ; Carcinoma, Non-Small-Cell Lung ; metabolism ; Humans ; Janus Kinases ; metabolism ; Lung Neoplasms ; metabolism ; STAT3 Transcription Factor ; metabolism ; Signal Transduction ; genetics ; physiology

BACKGROUNDAdvances in the understanding of cardiovascular pathogenesis have highlighted that inflammation plays a central role in atherosclerotic coronary heart disease. Therefore, exploring pharmacologically based anti-inflammatory treatments to be used in cardiovascular therapeutics is worthwhile to promote the discovery of novel ways of treating cardiovascular disorders.

METHODSThe myocardial cell line H9c2(2-1) was exposed to lipopolysaccharide (LPS) in culture and resulted in a cellular pro-inflammation status. miR-21 microRNA levels were detected using quantitative real-time polymerase chain reaction (Q-RT-PCR). The influence of lovastatin on miR-21 under normal and pro-inflammatory conditions was tested after being added to the cell culture mixture for 24 hours. Conditional gene function of two predicted cardiovascular system relevant downstream targets of miR-21, protein phosphatase 1 regulatory subunit 3A (PPP1R3A) and signal transducer and activator of transcription 3 (STAT3), were analyzed with immunoblotting.

RESULTSForty-eight hours of LPS treatment significantly increased the miR-21 to 170.71%± 34.32% of control levels (P = 0.002). Co-treatment with lovastatin for 24 hours before harvesting attenuated the up-regulation of miR-21 (P = 0.013). Twenty-four hours of lovastatin exposure up-regulated PPP1R3A to 143.85%± 21.89% of control levels in cardiomyocytes (P = 0.023). Lovastatin up-regulated the phosphorylation level of STAT3 compared to the background LPS pretreatment (P = 0.0077), this effect was significantly (P = 0.018) blunted when miR-21 was functionally inhibited.

CONCLUSIONSmiR-21 plays a major role in the regulation of the cellular anti-inflammation effects of lovastatin.

Blotting, Western ; Cell Line ; Humans ; Lipopolysaccharides ; pharmacology ; Lovastatin ; pharmacology ; MicroRNAs ; genetics ; Myocardium ; metabolism ; Myocytes, Cardiac ; drug effects ; metabolism ; Phosphoprotein Phosphatases ; metabolism ; Phosphorylation ; STAT3 Transcription Factor ; metabolism

The present study was to determine the effect of c-SRC on the viability of human cervical cancer HeLa cells and the expression of phosphorylated signal transducer and activator of transcription-3 (p-STAT3) of the cell. Post-transfection of c-SRC RNA interference vector, RT-PCR and Western blot were utilized to observe the contents of c-SRC mRNA and protein, respectively, in HeLa cells. The MTT was used to observe the viability of the cells. Cell cycle was observed by flow cytometry. The content of p-STAT3 in the cells was also investigated after knockdown of c-SRC. Knockdown of c-SRC significantly decreased the contents of c-SRC mRNA and protein in the cells. The viability of the cells decreased by 23.1%, 29.3%, 38.6% and 45.0% (all P < 0.05), respectively, after the cells were transfected with c-SRC RNA interference vector for 24, 48, 72, and 96 h. The number of S-phase cells decreased by 5.6%, 10.0%, 15.2% and 19.9% (all P < 0.05), respectively, after transfection of c-SRC RNA interference vector for 24, 48, 72, and 96 h. The content of p-STAT3 also decreased when c-SRC was knockdowned. Compared with the control group, after treatment of HeLa cells with STAT3 inhibitor Piceatannol for 24, 48, 72, and 96 h, the cell viability decreased by 23.8%, 29.7%, 37.3% and 45.4% (all P < 0.05), respectively, while increase of c-SRC content could not reverse the inhibitory effect. These results suggest that the inhibited viability of HeLa cells caused by knockdown of c-SRC is associated with the decreased content of p-STAT3 protein.
Cell Survival ; Female ; Gene Expression Regulation, Neoplastic ; Gene Knockdown Techniques ; Genes, src ; genetics ; HeLa Cells ; Humans ; Phosphorylation ; RNA, Messenger ; biosynthesis ; genetics ; STAT3 Transcription Factor ; genetics ; metabolism ; Transfection

OBJECTIVE: To investigate the regulation of hepatitis C virus (HCV) core protein on the activity of signal transducers and activators of transcription 3 (stat3). METHODS: A cell line expressing stable HCV core protein-QSG7701-core was constructed by transfecting the pcDNA3. 1-core (expressing HCV core protein) into the human immortalized hepatocyte line QSG7701. The phosphorylation and DNA binding activity of stat3 were detected by immunocytochemistry, Western blot, and electrophoretic mobility shift assay (EMSA). RESULTS: The expression level of phosphorylated stat3 in QSG7701-core cells was significantly lower than that in QSG7701-pcDNA3. 1 cells and untransfected QSG7701 cells, but there were no significant differences in the expression levels of total stat3 among the 3 groups. The positive signal of phosphorylated stat3 in nucleus of QSG7701-core cells was obviously weaker than that in QSG7701-pcDNA3. 1 cells and untransfected QSG7701 cells. EMSA showed that DNA binding activity of stat3 in QSG7701-core cells significantly decreased. CONCLUSION The expressionof HCV core protein in human hepatocyte line may suppress the phosphorylation and DNA binding activity of stat3, which may be one of the causes for resistance against interferon.
Cell Line ; DNA-Binding Proteins ; metabolism ; Hepatocytes ; cytology ; metabolism ; Humans ; STAT3 Transcription Factor ; metabolism ; Signal Transduction ; Transfection ; Viral Core Proteins ; biosynthesis ; genetics