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SRY (sex determining region Y)-box 9 (SOX9) is required for oncogenic Kras-mediated acinar-to-ductal metaplasia (ADM), pancreatic intraepithelial neoplasias (PanINs) and ultimately pancreatic ductal adenocarcinoma (PDAC). However, how oncogenic Kras affects SOX9 activity is not yet understood, and SOX9-associated genes in PDAC are also unknown at all. Here, we investigated the mechanistic link between SOX9 and oncogenic Kras, studied biological function of SOX9, and identified SOX9-related genes and their clinical significance in patients with PDAC. Our studies reveal that oncogenic Kras induces SOX9 mRNA and protein expression as well as phosphorylated SOX9 expression in human pancreatic ductal progenitor cells (HPNE) and pancreatic ductal cells (HPDE). Moreover, oncogenic Kras promoted nuclear translocation and transcriptional activity of SOX9 in these cells. TAK1/IκBα/NF-κB pathway contributed to induction of SOX9 by oncogenic Kras, and SOX9 in turn enhanced NF-κB activation. SOX9 promoted the proliferation of HPNE and PDAC cells, and correlated with minichromosome maintenance complex components (MCMs) and mediator of DNA damage checkpoint 1 (MDC1) expression. The overexpressive MDC1 was associated with less perineural and lymph node invasion of tumors and early TNM-stage of patients. Our results indicate that oncogenic Kras induces constitutive activation of SOX9 in HPNE and HPDE cells, and Kras/TAK1/IκBα/NF-κB pathway and a positive feedback between SOX9 and NF-κB are involved in this inducing process. SOX9 accelerates proliferation of cells and affects MCMs and MDC1 expression. MDC1 is associated negatively with invasion and metastasis of PDAC.

Metastatic relapse remains largely incurable and a major challenge of clinical management in breast cancer, but the underlying mechanisms are poorly understood. Herein, we report that CGI-99 is overexpressed in breast cancer tissues from patients with metastatic recurrence within 5 years. High CGI-99 significantly predicts poorer 5-year metastasis-free patient survival. We find that CGI-99 increases breast cancer stem cell properties, and potentiates efficient tumor lung colonization and outgrowth in vivo. Furthermore, we demonstrate that CGI-99 activates the autocrine interleukin-6 (IL-6)/STAT3 signaling by increasing the accumulation and activity of RNA polymerase II and p300 cofactor at the proximal promoter of IL-6. Importantly, delivery of the IL-6-receptor humanized monoclonal antibody tocilizumab robustly abrogates CGI-99-induced metastasis in vivo. Finally, we find that high levels of CGI-99 are significantly correlated with STAT3 hyperactivation in breast cancer patients. These findings reveal a potential mechanism for constitutive activation of autocrine IL-6/STAT3 signaling and may suggest a novel target for clinical intervention in breast cancer.

The LIM protein AJUBA is a scaffold protein participating in the regulation of cell adhesion, mitosis, DNA damage, cell differentiation, proliferation, migration and gene transcription. However, its roles in tumorigenesis and progression are poorly defined. Here, we report that AJUBA is highly expressed in colorectal cancer (CRC) and promotes CRC cell growth in culture and in xenografted mice via an inhibition of apoptosis. AJUBA represses the expression of IFIT2 gene, an interferon-stimulated gene and a known apoptosis inducer and tumour suppressor to mediate its resistance to apoptosis. Mechanistic investigations reveal that AJUBA specifically binds the FERM domain of JAK1 to dissociate JAK1 from the IFNγ recepter, resulting in an inhibition of STAT1 phosporylation and concomitantly its nuclear translocation. Clinically, the level of AJUBA in CRC specimens is negatively correlated with the levels of IFIT2 and pSTAT1. Collectively, these studies demonstrate that AJUBA can promote CRC growth via inhibiting apoptosis and serve as a target for the therapeutics and a marker for diagnosis of CRC.

The aim of this study was to explore the correlation between visit-to-visit and short-term blood pressure variability (BPV), including systolic BPV (SBPV) and diastolic BPV (DBPV), calculated using different methods, and the glomerular filtration rate (GFR) in a late, middle-aged population. Using cluster sampling, we randomly selected retired employees of the Kailuan Group who were ⩾60 years and participated in a third health examination for 24-h ambulatory blood pressure monitoring and inspection. Among the 3064 randomly selected observation subjects, 2464 were included based on the criteria. BPV was calculated using s.d., coefficient of variation (CV, s.d./Mean), variability independent of mean (VIM, s.d./Mean x ) and BPV ratio (BPVR, s.d. (SBPV)/s.d. (DBPV)). Multivariate linear regression was used to analyse the correlation between estimated GFR (eGFR) and BPV calculated using different methods. The mean age of 2464 subjects was 67.4±6.1 years, with 1667 male subjects (67.7%). A total of 2104 cases were included in the visit-to-visit BPV group, and 1382 in the short-term BPV group. SBPV calculated using different methods showed statistically significant increasing trends for the SBP versus all s.d. and short-term BPVR. There was a significant, positive correlation between the visit-to-visit and short-term BPV calculated using different methods, which were all negatively correlated with eGFR (P<0.05). Multivariate linear regression analysis showed that, with correction for possible confounding factors, SBPV (24-h s.d., CV and VIM, and daytime CV and night time CV) and all DBPV demonstrated negative linear relationships with eGFR (P<0.05).

Gliomas are highly malignant brain tumors that are highly invasive and resistant to conventional therapy. Receptor tyrosine kinases (RTKs) such as PDGFRα (platelet-derived growth factor receptor-α), which show frequent aberrant activation in gliomas, are associated with a process of epithelial-mesenchymal transition (EMT), a cellular alteration that confers a more invasive and drug-resistant phenotype. Although this phenomenon is well documented in human cancers, the processes by which RTKs including PDGFRα mediate EMT are largely unknown. Here, we report that SHP-2 (encoded by PTPN11) upregulates an EMT inducer, ZEB1, to mediate PDGFRα-driven glioma EMT, invasion and growth in glioma cell lines and patient-derived glioma stem cells (GSCs) using cell culture and orthotopic xenograft models. ZEB1 and activated PDGFRα were coexpressed in invasive regions of mouse glioma xenografts and clinical glioma specimens. Glioma patients with high levels of both phospho-PDGFRα (p-PDGFRα) and ZEB1 had significantly shorter overall survival compared with those with low expression of p-PDGFRα and ZEB1. Knockdown of ZEB1 inhibited PDGFA/PDGFRα-stimulated glioma EMT, tumor growth and invasion in glioma cell lines and patient-derived GSCs. PDGFRα mutant deficient of SHP2 binding (PDGFRα-F720) or phosphoinositide 3-kinase (PI3K) binding (PDGFRα-F731/42), knockdown of SHP2 or treatments of pharmacological inhibitor for PDGFRα-signaling effectors attenuated PDGFA/PDGFRα-stimulated ZEB1 expression, cell migration and GSC proliferation. Importantly, SHP-2 acts together with PI3K/AKT to regulate a ZEB1-miR-200 feedback loop in PDGFRα-driven gliomas. Taken together, our findings uncover a new pathway in which ZEB1 functions as a key regulator for PDGFRα-driven glioma EMT, invasiveness and growth, suggesting that ZEB1 is a promising therapeutic target for treating gliomas with high PDGFRα activation., Competing Interests: The authors declare no conflict of interest.

Systematic investigation with large sample size of the distribution of etiologies of renal artery stenosis (RAS) is scant in both Western countries and China. We retrospectively analyzed the etiology of RAS in 2047 consecutive inpatients diagnosed with RAS for hypertension at Fuwai Hospital between 1999 and 2014. The number of patients with atherosclerosis was 1668 (81.5%), 259 (12.7%) with Takayasu's arteritis (TA), 86 (4.2%) with fibromuscular dysplasia (FMD), 34 (1.6%) with other causes. There was an obvious increase with age in the proportion of atherosclerotic RAS (P<0.001). In patients aged ⩽40 years (n=319) the predominant etiology of RAS was TA (60.5%), followed by FMD (24.8%). In patients aged >40 years (n=1728) the major cause of RAS was atherosclerosis (94.7%), followed by TA (3.8%).The proportion of TA and FMD in female patients was significantly higher than that in male patients (P<0.001). In female patients aged ⩽40 years (n=215), the top three etiologies of RAS were TA (68.4%), FMD (27.9%) and atherosclerosis (1.4%). The present analysis showed that atherosclerosis, TA and FMD were sequentially the top three causes of RAS in the National Center of China. Age and gender had a significant effect on the distribution of etiologies of RAS.

MicroRNAs have been shown to play an important role in normal hematopoisis and leukemogenesis. Here, we report function and mechanisms of miR-181 family in myeloid differentiation and acute myeloid leukemia (AML). The aberrant overexpression of all the miR-181 family members (miR-181a/b/c/d) was detected in French-American-British M1, M2 and M3 subtypes of adult AML patients. By conducting gain- and loss-of-function experiments, we demonstrated that miR-181a inhibits granulocytic and macrophage-like differentiation of HL-60 cells and CD34+ hematopoietic stem/progenitor cells (HSPCs) by directly targeting and downregulating the expression of PRKCD (which then affected the PRKCD-P38-C/EBPα pathway), CTDSPL (which then affected the phosphorylation of retinoblastoma protein) and CAMKK1. The three genes were also demonstrated to be the targets of miR-181b, miR-181c and miR-181d, respectively. Significantly decreases in the expression levels of the target proteins were detected in AML patients. Inhibition of the expression of miR-181 family members owing to Lenti-miRZip-181a infection in bone marrow blasts of AML patients increased target protein expression levels and partially reversed myeloid differentiation blockage. In the mice implanted with AML CD34+ HSPCs, expression inhibition of the miR-181 family by Lenti-miRZip-181a injection improved myeloid differentiation, inhibited engraftment and infiltration of the leukemic CD34+ cells into the bone marrow and spleen, and released leukemic symptoms. In conclusion, our findings revealed new mechanism of miR-181 family in normal hematopoiesis and AML development, and suggested that expression inhibition of the miR-181 family could provide a new strategy for AML therapy.

MicroRNAs have emerged as crucial regulators of cardiac homeostasis and remodeling in various cardiovascular diseases. We previously demonstrated that miR-221 regulated cardiac hypertrophy in vitro. In the present study, we demonstrated that the cardiac-specific overexpression of miR-221 in mice evoked cardiac dysfunction and heart failure. The lipidated form of microtubule-associated protein 1 light chain 3 was significantly decreased and sequestosome 1 was accumulated in cardiac tissues of transgenic (TG) mice, indicating that autophagy was impaired. Overexpression of miR-221 in vitro reduced autophagic flux through inhibiting autophagic vesicle formation. Furthermore, mammalian target of rapamycin (mTOR) was activated by miR-221, both in vivo and in vitro. The inactivation of mTOR abolished the miR-221-induced inhibition of autophagy and cardiac remodeling. Our previous study has demonstrated that cyclin-dependent kinase (CDK) inhibitor p27 was a direct target of miR-221 in cardiomyocytes. Consistently, the expression of p27 was markedly suppressed in the myocardia of TG mice. Knockdown of p27 by siRNAs was sufficient to mimic the effects of miR-221 overexpression on mTOR activation and autophagy inhibition, whereas overexpression of p27 rescued miR-221-induced autophagic flux impairment. Inhibition of CDK2 restored the impaired autophagic flux and rescued the cardiac remodeling induced by either p27 knockdown or miR-221 overexpression. These findings reveal that miR-221 is an important regulator of autophagy balance and cardiac remodeling by modulating the p27/CDK2/mTOR axis, and implicate miR-221 as a therapeutic target in heart failure.

A-kinase-interacting protein 1 (AKIP1) is found to be overexpressed in breast and prostate cancers, suggesting that AKIP1 might act as a potent oncogenic protein. However, the clinical significance and biological role of AKIP1 in cancer progression remain largely unknown. Herein, we report that AKIP1 is markedly overexpressed in esophageal squamous cell carcinoma (ESCC) cell lines and clinical ESCC samples. AKIP1 expression significantly correlates with ESCC progression and patients' shorter survival time. Furthermore, we find that overexpressing AKIP1 induces, whereas silencing AKIP1 reduces, ESCC angiogenesis and lymphangiogenesis both in vitro and in vivo. Moreover, we demonstrate that AKIP1 transcriptionally upregulates vascular endothelial growth factor-C (VEGF-C) via interaction with its promoter through cooperation with multiple transcriptional factors, including SP1, AP2 and nuclear factor-κB (NF-κB). Importantly, significant correlation between levels of AKIP1 and VEGF-C is observed in a cohort of human ESCC, as well as in non-small cell lung cancer, hepatocellular carcinoma and ovarian cancer. Hence, these findings indicate an important role for AKIP1 in ESCC angiogenesis and lymphangiogenesis, and uncover a novel mechanism for the upregulation of VEGF-C in cancers.

Cilium is a conservative cell organelle, found in many types of cell surfaces. Cilia are tail-like prominence protruding out of the cell surface, capable of locomotion and acting as the cell's signal transduction sensory organs with their complex structures and ingenious function. Studies have shown that ciliary pathological changes and defects are related to the development of many diseases, including renal cysts, infertility, organ reversal, obesity and so on. The inactivation and mutation of cilia-related proteins can cause tumors, such as neoplasms, intestinal cancer, myeloma, rhabdomyosarcoma and adenocarcinoma. Adenomatous polyposis coli (APC) is a kind of multifunctional protein encoded by the APC gene that participates in many vital activities of organisms. The mutation of APC can lead to familial adenomatous polyposis, and also has a role in the development of human tumors, such as gastric cancer, esophageal cancer and breast carcinoma. Recent studies indicate that the abnormal mutation of APC may lead to some diseases caused by abnormal growth of cilia. Herein, the development of studies on cilia, APC and associated diseases are summarized in brief.

Inducible acetylation of p53 at lysine residues has a great impact on regulating the transactivation of this protein, which is associated with cell growth arrest and/or apoptosis under various stress conditions. However, the factor(s) for regulating p53 acetylation remains largely unknown. In the current study, we have shown that p85α, the regulatory subunit of phosphatidylinositol-3-kinase, has a critical role in mediating p53 acetylation and promoter-specific transactivation in the ultraviolet B (UVB) response. Depletion of p85α in mouse embryonic fibroblasts significantly impairs UVB-induced apoptosis, as well as p53 transactivation and acetylation at Lys370 (Lys373 of human p53); however, the accumulation, nuclear translocation and phosphorylation of p53 are not affected. Interestingly, p85α binds to p300, promotes the p300-p53 interaction and the subsequent recruitment of the p53/p300 complex to the promoter region of the specific p53 target gene in response to UVB irradiation. Moreover, ablation of p53 acetylation at Lys370 by site-directed mutagenesis dramatically suppresses UVB-induced expression of the specific p53-responsive gene as well as cell apoptosis. Therefore, we conclude that p85α is a novel regulator of p53-mediated response under certain stress conditions, and targeting the p85α-dependent p53 pathway may be promising for cancer therapy.

Galectin-3 (Gal3) has important roles in tumor transformation and metastasis. This study shows that c-Abl and Abl-related gene (Arg) associate with and phosphorylate Gal3. The SH (Src homology)3 domains of c-Abl/Arg bind to a P(80)GPPSGP motif of Gal3, and Tyr79 and Tyr118 are the major tyrosine phosphorylation sites. A consequence of this interaction and phosphorylation is the significant impairment of chaperone-mediated autophagy of Gal3. Cells expressing Gal3 and treated with the c-Abl/Arg inhibitor STI571, Gal3-depleted cells, and Gal3-depleted cells expressing Gal3 phosphorylation mutants all display an increased sensitivity to apoptosis-inducing agents. In addition, tumor cells expressing the phosphorylation mutants show impaired tumorigenicity. These results partially explain the antiapoptotic effect of Abl and Arg. As tumors frequently overexpress Gal3, a c-Abl/Arg-specific inhibitor may potentially be applied along with other antitumor drugs to target the lysosomal degradation of Gal3 in tumor therapy.

We have previously reported that astrocyte elevated gene-1 (AEG-1) was upregulated in human breast cancer. However, the biological function of AEG-1 in the development and progression of breast cancer remains to be clarified. In this study, we examined the effect of AEG-1 on cell proliferation and found that AEG-1 upregulation was significantly linked to increased Ki67 (P<0.001). Ectopic expression of AEG-1 in MCF-7 and MDA-MB-435 breast cancer cells dramatically enhanced cell proliferation and their ability of anchorage-independent growth, whereas silencing endogenous AEG-1 with shRNAs inhibited cell proliferation and colony-forming ability of the cells on soft agar. Furthermore, these proliferative effects were significantly associated with decreases of p27Kip1 and p21Cip1 two key cell-cycle inhibitors. Moreover, we further demonstrated that AEG-1 could downregulate the transcriptional activity of FOXO1 by inducing its phosphorylation through the PI3K/Akt signaling pathway. These observations were further confirmed in clinical human primary breast cancer specimens, in which high-level expression of AEG-1 was inversely correlated with the expression of FOXO1. Taken together, our results provide the first demonstration of a novel mechanism by which AEG-1 induces proliferation of breast cancer cell, and our findings suggest that AEG-1 might play an important role in tumorigenesis of breast cancer.

Stimulation of death receptors activates the extrinsic apoptotic signaling pathway that leads to cell death. Although many steps of this apoptotic signaling cascade are known, few mechanisms that counterbalance the death signal have been described. We identified an antiapoptotic protein complex associated with death receptors that contains glycogen synthase kinase-3 (GSK3), DDX3 and cellular inhibitor of apoptosis protein-1 (cIAP-1). GSK3, DDX3 and cIAP-1 are associated in cells with each other and with death receptors. Blocking the actions of GSK3 or DDX3 potentiated caspase-3 activation induced by stimulation of four different death receptors in several types of cells. GSK3 restrained apoptotic signaling by inhibiting formation of the death-inducing signaling complex and caspase-8 activation. Stimulated death receptors surmount the antiapoptotic complex by causing GSK3 inactivation and cleavage of DDX3 and cIAP-1 to enable progression of the apoptotic signaling cascade, but the antiapoptotic complex remains functional in cancer cells resistant to death receptor stimulation, a resistance that is overcome by GSK3 inhibitors. Thus, an antiapoptotic complex of GSK3, DDX3 and cIAP-1 caps death receptors, providing a checkpoint to counterbalance apoptotic signaling.

Secreted protein acidic and rich in cysteine (SPARC) is an extracellular glycoprotein expressed in several solid cancers, including malignant gliomas, upon adoption of metastatic or invasive behaviors. SPARC expression in glioma cells promotes invasion and survival under stress, the latter process dependent on SPARC activation of AKT. Here we demonstrate that downregulation of SPARC expression with short interfering RNA (siRNA) in glioma cells decreased tumor cell survival and invasion. SPARC siRNA reduced the activating phosphorylation of AKT and two cytoplasmic kinases, focal adhesion kinase (FAK) and integrin-linked kinase (ILK). We determined the contributions of FAK and ILK to SPARC effects using SPARC protein and cell lines engineered to overexpress SPARC. SPARC activated FAK and ILK in glioma cells previously characterized as responsive to SPARC. Downregulation of either FAK or ILK expression inhibited SPARC-mediated AKT phosphorylation, and targeting both FAK and ILK attenuated AKT activation more potently than targeting either FAK or ILK alone. Decreased SPARC-mediated AKT activation correlated with a reduction in SPARC-dependent invasion and survival upon the downregulation of FAK and/or ILK expression. These data further demonstrate the role of SPARC in glioma tumor progression through the activation of intracellular kinases that may provide novel therapeutic targets for advanced cancers.

Previous studies have demonstrated that antigen-specific tolerance could be induced by lipopolysaccharide (LPS)-stimulated B cells retrovirally transduced with an immunoglobulin-antigen (or epitope-containing peptide) fusion construct. To investigate the mechanism of this gene therapy system, we now adapted this approach to immunotherapy of spontaneous diabetes in nonobese diabetic (NOD) mice, a T-cell-mediated autoimmune disease triggered, in part, by a pathogenic response to glutamate decarboxylase (GAD) 65. We demonstrate that LPS-stimulated splenocytes, retrovirally transfected with GAD-IgG fusion construct, induce a significant antigen-specific hyporesponsiveness at both cellular and humoral levels and reduce the incidence of diabetes in female NOD mice. Parallel with disease protection, we observed a prolonged increase of the numbers of CD4+CD25+ T cells in the periphery of GAD-IgG-treated mice, compared to those treated with a control IgG vector, both in the prediabetic period and persisting even 8 months after gene therapy. This increase appeared to be induced by the repeated stimulation of the antigen in the periphery instead of a result of differentiation of T-cell precursor in the thymus. Moreover, CD4+CD25+ T cells induced by GAD-IgG fusion construct were capable of suppressing the proliferative response of CD4+CD25- T cells in vitro; and ablation of the activity of CD4+CD25+ T cells by blocking antibody against CD25 could reverse GAD-specific T-cell hyporesponsiveness. These results suggested that CD4+CD25+ T-cell subset induced in GAD-IgG-treated NOD mice represented the regulatory or suppressive CD4+CD25+ T cells (Treg) and might play an important role in the induction and maintenance of tolerance in NOD mice. Furthermore, the numbers of splenic CD4+CD62L+ regulatory T cells in GAD-IgG-treated mice during the prediabetic period and serum TGF-beta levels in 34-38-week-old GAD-IgG-protected mice were also increased, compared to control IgG-treated ones. Therefore, we propose that the induction of tolerance and the prevention of diabetes incidence in NOD female mice induced by the GAD-IgG fusion construct may require CD4+ regulatory T cells, and the possible mediation of TGF-beta.

Delivery of genes to the lung has enormous potential in a wide variety of illnesses, from lung cancer to genetic deficiency diseases. Many delivery systems have been utilized, each with its own advantages and limitations. Polyethylenimine is a polycation capable of binding and compacting DNA, enabling intravascular plasmid delivery to normal tissues in such a way that the plasmid can be expressed in a proportion of the exposed cells. We have developed a novel intravenous method to deliver small amounts of plasmid to lung tissue, using nontoxic quantities of polyethylenimine in combination with albumin (or other soluble proteins). Injection of 1 microg or less of plasmid resulted in highly efficient gene expression in lung interstitial and endothelial tissues (0.5 to 1 ng luciferase per microg plasmid DNA), while larger quantities of plasmid reduced relative gene expression. Using luciferase as a reporter gene, single injections had maximal gene expression between 24 and 48 h, with a rapid decline thereafter. In contrast to some other delivery systems, however, no inhibition of gene expression occurred during multiple rounds of plasmid administration through 20 days. As a result, this method may have useful applications in diseases that could benefit from recurrent therapeutic gene delivery.

The glucocorticoid receptor (GR) mediates glucocorticoid stimulation of surfactant production by fetal mammalian lung. In many other tissues, glucorticoids decrease expression of GR, thereby reducing responsiveness to these hormones. We therefore determined whether there is a similar effect of exogenous glucocorticoids on GR in fetal rat whole lung, and in the principal cell types involved in the stimulation of surfactant, the fibroblasts and the epithelial cells. The ontogeny of GR in late gestation lung differed between the two cell types, with maximal levels occurring in fibroblasts on gestational d 19, and on d 20 in epithelial cells. Administration of dexamethasone (1 mg/kg) to the mother on gestational d 18 or 19 (term = 22 d) increased specific GR binding activity in whole lung 24 h later. Furthermore, in vitro, incubation of cultured fibroblasts of gestational d 20 with 10(-7) M cortisol increased GR immunoreactive protein and binding activity in a dose- and time-dependent manner, without affecting cellular levels of GR mRNA. However, identical treatment of d 20 distal airway epithelial cells was followed by decreased GR protein without significant change in cellular GR mRNA. Surfactant protein-A protein levels, taken as assessments of lung maturation, were increased in response to the same treatment. Our findings suggest that hormonal regulation of GR in fetal lung cells occurs at a posttranscriptional level, and is cell-specific. In the context of substantial increases in circulating glucocorticoid concentrations during late gestation, these findings may be of physiologic importance to the biochemical maturation of the antenatal lung.