The silencing of disease-causing genes with small interfering RNA (siRNA) offers a particularly effective therapeutic strategy for different disorders; however, its clinical efficacy relies on the development of nontoxic and tissue-specific delivery vehicles. Herein, we report that bioresponsive chimaeric polymersomes (BCP) with short poly(ethylenimine) as inner shell mediate highly efficacious, sustained, and liver-specific siRNA transfection in vivo. BCP exhibited remarkable encapsulation efficiencies of siRNA (95-100%) at siRNA-feeding contents of 15-25 wt %, to afford stable, small-sized (55-64 nm), and neutral-charged BCP-siRNA. siApoB-Loaded BCP (BCP-siApoB) outperformed lipofectamine counterparts and silenced 93% of ApoB mRNA in HepG2 cells at 50 nM siApoB without inducing cytotoxicity. Intriguingly, the in vivo studies using wild-type C57BL/6 mice revealed that BCP-siApoB preferentially accumulated in the liver, and a single dose of 4.5 mg/kg achieved over 90% downregulation of ApoB mRNA for at least 10 days. The systemic administration of BCP-siApoB at 4.5 mg/kg every 2 weeks or 1.5 mg/kg weekly in diet-induced obese mice could also achieve up to 80% silencing of ApoB mRNA. The liver specificity and silencing efficacy of BCP-siApoB could further be improved by decorating it with the trivalent N-acetylgalactosamine (TriGalNAc) ligand. These bioresponsive and liver-specific chimaeric polymersomes provide an enabling technology for siRNA therapy of various liver-related diseases.

Oral squamous cell carcinoma (OSCC) is a common head-and-neck cancer with a deficiency of early diagnosis and poor prognosis. To identify potential diagnostic and prognostic markers of OSCC, we firstly used weighted gene co-expression network analysis (WGCNA) to build a co-expression module from GSE42743. Next, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses on specified units from selected modules utilizing Database for Annotation, Visualization, and Integrated Discovery (DAVID). Additionally, we identified and validate hub genes of these specified modules from multiple datasets like GEPIA and TCGA. In total 16 co-expression modules were built by 17,238 genes of 74 tumor samples utilizing WGCNA. Through pathway and functional enrichment analysis, the turquoise module was most firmly relevant to the cell cycle, oocyte meiosis, and p53 signaling pathway. Hub genes VRK1, NUP37, HMMR, SPC25, and RUVBL1 were identified to be related to oral cancer at both molecular level and clinical levels. The expressions of these genes differed in tumor tissues and normal tissues. Meanwhile, patients with high hub gene expression had a poor prognosis clinically. To conclude, five hub genes were identified to be relevant to oral cancer from the molecular level and the clinical level. Therefore, the detection of these genes was of great significance. They can be regarded as diagnostic and prognostic biomarkers for oral cancer. Also, they could shed light on the improvement of patients' overall survival and prognosis, which needs further analysis in the future.

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies and primarily presents with hyperandrogenism. Although environmental factors and genetic factors are thought to be the major reason, there still exists a lot of questions need to be answered. High expression of C-terminal-binding protein 1 antisense (CTBP1-AS) was identified as an independent risk factor for PCOS; however, the molecular mechanism of CTBP1-AS in PCOS regulation is unknown. In the present study, the expression level of CTBP1-AS was found to be significantly upregulated in patients with PCOS compared with healthy control patients. CTBP1-AS knockdown was demonstrated to reduce the proliferation and promote the apoptosis of granulosa tumor cells in vitro. It was also identified that the two core catalytic subunits of Polycomb repressive complex 2 (enhancer of zeste homolog 2 and embryonic and ectoderm development protein) interacted with CTBP1-AS in primary granulosa cells and KGN cells. In addition, cryptotanshinone treatment was demonstrated to effectively downregulate CTBP1-AS expression level. Data from the present study suggested a pathophysiological role of CTBP1-AS in PCOS and may provide a new potential target for PCOS treatment.

High-mobility group nucleosome-binding domain 4 (HMGN4) exerts biological functions by regulating gene transcription through binding with nucleosome. As a new epigenetic regulator discovered in 2001, its biological functions have not been clarified. HMGN4 belongs to HMGNs family, in which HMGN1, 2 and 5 have been reported to play roles in oncogenesis of various cancers. However, it is reported that HMGN4 was associated with thyroid and liver cancer. In this study, we discovered for the first time that HMGN4 was highly expressed in human triple-negative breast cancer (TNBC), based on the analysis of the TCGA database. Moreover, we found that HMGN4 controlled the proliferation of human TNBC cells both in vitro and in vivo. Mechanistically, the positive correlation occurred between HMGN4 and STAT3 downstream genes while HMGN4 played an indispensable role in constitutively active STAT3 (STAT3C) induced colony formation. Interestingly, we reported that STAT3 regulated HMGN4 transcription as its transcriptional factor by chromatin immunoprecipitation and HMGN4 promoter-luc assays. That is to say, there is a feed-forward signaling circuit between HMGN4 and STAT3, which might control TNBC cell growth. Finally, we proved that the interference of HMGN4 by nanovehicle-packaged siRNA may be a potentially effective approach in TNBC treatment. In summary, our findings not only identified a novel regulator in TNBC cell proliferation but also revealed the mechanism by which HMGN4 acted as a downstream gene of STAT3 to participate in the STAT3 pathway, which indicated that HMGN4 was likely to be a potential novel target for anti-TNBC therapy.

Abstract Cancer progression is highly dependent on the ability of cancer cell tumor formation, in which epigenetic modulation plays an essential role. However, the epigenetic factors promoting breast tumor formation are less known. Screened from three-dimensional (3D)-sphere tumor formation model, HMGN5 that regulates chromatin structures became the candidate therapeutic target in breast cancer, though its role is obscure. HMGN5 is highly expressed in 3D-spheres of breast cancer cells and clinical tumors, also an unfavorable prognostic marker in patients. Furthermore, HMGN5 controls tumor formation and metastasis of breast cancer cells in vitro and in vivo. Mechanistically, HMGN5 is governed by active STAT3 transcriptionally and further escorts STAT3 to shape the oncogenic chromatin landscape and transcriptional program. More importantly, interference of HMGN5 by nanovehicle-packaged siRNA effectively inhibits tumor growth in breast cancer cell–derived xenograft mice model. Implications: Our findings reveal a novel feed-forward circuit between HMGN5 and STAT3 in promoting breast cancer tumorigenesis and suggest HMGN5 as a novel epigenetic therapeutic target in STAT3-hyperactive breast cancer.

Juvenile idiopathic arthritis (JIA) is a common autoimmune disease characterized by environmental influences along with several predisposing genes in the pathogenesis. The protein tyrosine phosphatase nonreceptor 22 (PTPN22) and signal transducer and activator of transcription factor 4 (STAT4) have been recognized as susceptibility genes for numerous autoimmune diseases. Associations of STAT4 rs7574865 G/T and PTPN22 (rs2488457 G/C and rs2476601 C/T) polymorphisms with JIA have repeatedly been replicated in several Caucasian populations. The aim of this study was to investigate the influence of three polymorphisms mentioned above on the risk of developing JIA in Han Chinese patients. Genotyping was performed on a total of 137 Chinese patients with JIA (JIA group) and 150 sex and age frequency-matched healthy volunteers (Control group). The single-nucleotide polymorphisms (SNP) were determined by using direct sequencing of PCR-amplified products. There were significant differences of PTPN22 rs2488457 G/C and STAT4 rs7574865 G/T polymorphisms between both groups. However, no significant difference was observed in distribution frequencies of PTPN22 rs2476601 polymorphism. The association with the PTPN22 rs2488457 G/C polymorphism remained significant in the stratifications by age at onset, ANA status, splenomegaly, lymphadenectasis and involvement joints. As with the STAT4 rs7574865 G/T polymorphisms, the enthesitis-related arthritis and presence of hepatomegaly had strong effect on the association. Our data strengthen STAT4 rs7574865 G/T and PTPN22 rs2488457 G/C polymorphisms as susceptibility factors for JIA.

Through silencing tumor suppressor genes, epigenetic changes can activate signaling pathways important to cancer development. In this report, we found an epigenetic contribution to the aberrant activation of wnt signaling in human gastric cancer. CXXC4 (CXXC finger protein 4) was identified as a novel target of EZH2 (enhancer of zeste homolog 2), and EZH2 promotes the activation of wnt singaling by downregulating CXXC4 expression. CXXC4 inhibits the growth of gastric cancer cells both in vitro and in vivo through inactivating wnt signaling. In contrast, depletion of CXXC4 activates wnt signaling and promotes the anchorage-independent growth of nontumor gastric epithelial cells. CXXC4 is downregulated in gastric carcinoma tissues and its downregulation is associated with poor outcome of gastric cancer patients (hazard ratio: 5.053, P <0.05). Through its binding to dishevelled (Dvl), CXXC4 stabilizes the destruction complex of β -catenin to inhibit wnt signaling. Two critical amino acid residues in CXXC4, K161 and T162 were found to be important to its binding to Dvl and the growth inhibitory effect of CXXC4. In summary, EZH2 promotes the activation of wnt signaling in gastric carcinogenesis through the downregulation of CXXC4 expression. CXXC4 is a novel potential tumor suppressor directly regulated by EZH2, and its expression is a significant prognosis factor for patients with early stages of gastric cancer.