Integrative Functional Genomics Implicated the Key T-/B-Cell Deficiency Regulator RAG1 in Transarterial Chemoembolization of Hepatocellular Carcinoma.

Transarterial chemoembolization (TACE) has significantly prolonged overall survival (OS) of unresectable hepatocellular carcinoma (HCC) patients. Unfortunately, there are still a portion of patients without therapeutic responses to TACE. Although genome-wide association studies identified multiple HCC susceptibility SNPs, it is still largely unclear how genome-wide identified functional SNPs impacting gene expression contribute to the prognosis of TACE-treated HCC patients. In this study, we developed an integrative functional genomics methodology to identify gene expression-related SNPs significantly contributing to prognosis of TACE-treated HCC patients across the whole genome. Employing integration of data from expression quantitative trait locus (eQTLs) analyses of The Cancer Genome Atlas (TCGA) liver hepatocellular carcinoma (LIHC) as well as the 1000 Genomes project, we successfully annotated 60 gene expression-related SNPs which are associated with OS of the TCGA patients. After genotyping these 60 SNPs in our TACE cohort, we identified four SNPs (rs12574873, rs12513391, rs34597395, and rs35624901) which are significantly associated with OS of HCC patients treated with TACE. For instance, multivariate Cox proportional hazards model indicated that the rs35624901 Deletion.Deletion (Del.Del) genotype carriers had markedly prolonged OS and a 55% decreased death risk compared with individuals with the GG genotype after TACE therapy (p = 8.3 × 10-5). In support of this, the rs35624901 Del.Del genotype is correlated to higher expression of RAG1, a key T-/B-cell deficiency regulator. Our findings reported the first evidence supporting the prognostic value of four eQTL SNPs in TACE-treated HCC patients. Importantly, our data implicated that antitumor immunity might contribute to TACE efficiency for unresectable HCC patients.

LncPSCA in the 8q24.3 risk locus drives gastric cancer through destabilizing DDX5.

Genome-wide association studies (GWAS) have identified multiple gastric cancer risk loci and several protein-coding susceptibility genes. However, the role of long-noncoding RNAs (lncRNAs) transcribed from these risk loci in gastric cancer development and progression remains to be explored. Here, we functionally characterize a lncRNA, lncPSCA, as a novel tumor suppressor whose expression is fine-regulated by a gastric cancer risk-associated genetic variant. The rs2978980 T > G change in an intronic enhancer of lncPSCA interrupts binding of transcription factor RORA, which down-regulates lncPSCA expression in an allele-specific manner. LncPSCA interacts with DDX5 and promotes DDX5 degradation through ubiquitination. Increased expression of lncPSCA results in low levels of DDX5, less RNA polymerase II (Pol II) binding with DDX5 in the nucleus, thus activating transcription of multiple p53 signaling genes by Pol II. These findings highlight the importance of functionally annotating lncRNAs in GWAS risk loci and the great potential of modulating lncRNAs as innovative cancer therapy.

Oncogenic SNORD12B activates the AKT-mTOR-4EBP1 signaling in esophageal squamous cell carcinoma via nucleus partitioning of PP-1α.

Esophageal cancer is a complex malignancy and the sixth leading cause of cancer death worldwide. In Eastern Asia including China, about 90% of all incident cases have esophageal squamous cell carcinoma (ESCC). Mounting evidence elucidates that aberrant expression of various non-coding RNAs (ncRNAs) contributes to ESCC progression, but it remains unclear how small nucleolar RNAs (snoRNAs) are involved in ESCC development. We systemically screened clinically relevant snoRNAs in ESCC via integrative analyses of The Cancer Genome Atlas (TCGA) data and validation in ESCC tissues. We found that snoRNA SNORD12B was one of the most evidently upregulated snoRNAs in ESCC specimens and its high expression was significantly associated with poor prognosis of patients. SNORD12B profoundly promoted proliferation, migration, invasion, and metastasis of ESCC cells in vitro and in vivo, indicating its oncogene nature. In particular, SNORD12B could interact with PP-1α, one of the three catalytic subunits of serine/threonine protein phosphatase 1, which is a major phosphatase that directly dephosphorylates AKT to suppress its activation. Interestingly, high levels of SNORD12B in ESCC cells could break interactions between 14-3-3ζ and PP-1α, abolish the retention of PP-1α in the cytosol by 14-3-3ζ and relocate PP-1α from the cytosol to the nucleus. This led to sequestered PP-1α in the nucleus, enhanced phosphorylation of AKT in the cytosol, activated AKT-mTOR-4EBP1 signaling, and, thus, ESCC progression. These insights would improve our understanding of how snoRNAs contribute to tumorigenesis and highlight the potential of snoRNAs as future therapeutic targets against cancers.

EPB41 suppresses the Wnt/ß-catenin signaling in non-small cell lung cancer by sponging ALDOC.

Despite advancements in therapeutic options, the overall prognosis for non-small-cell lung cancer (NSCLC) remains poor. Further exploration of the etiology and targets for novel treatments is crucial for managing NSCLC. In this study, we revealed the significant potential of EPB41 for inhibiting NSCLC proliferation, invasion and metastasis in vitro and in vivo. Consistent with its tumor suppressor role in NSCLC, the expression of EPB41 in NSCLC specimens evidently decreased compared to that in normal tissues, and low EPB41 expression was associated with poor prognoses for NSCLC patients. We further demonstrated the importance of EPB41 protein as a novel inhibitor of the Wnt signaling, which regulates ß-Catenin stability, and elucidated the crucial role of the EPB41/ALDOC/GSK3ß/ß-Catenin axis in NSCLC. Suppression of EPB41 expression in cancer cells elevated the levels of free ALDOC protein released from the EPB41-ALDOC complex, leading to disassembly of the ß-catenin destruction complex, reduced proteolytic degradation of ß-catenin, elevated cytoplasmic accumulation and nuclear translocation of ß-catenin, thereby activating the expression of multiple oncogenes and, thus, NSCLC pathogenesis. Our study highlights the potential of EPB41 as a future therapeutic target for lung cancer.

LncRNA SLC26A4-AS1 suppresses the MRN complex-mediated DNA repair signaling and thyroid cancer metastasis by destabilizing DDX5.

Lymph node metastasis is the major adverse feature for recurrence and death of thyroid cancer patients. To identify lncRNAs involved in thyroid cancer metastasis, we systemically screened differentially expressed lncRNAs in lymph node metastasis, thyroid cancer, and normal tissues via RNAseq. We found that lncRNA SLC26A4-AS1 was continuously, significantly down-regulated in normal tissues, thyroid cancer, and lymph node metastasis specimens. Low SLC26A4-AS1 levels in tissues were significantly associated with poor prognosis of thyroid cancer patients. LncRNA SLC26A4-AS1 markedly inhibited migration, invasion, and metastasis capability of cancer cells in vitro and in vivo. Intriguingly, SLC26A4-AS1 could simultaneously interact with DDX5 and the E3 ligase TRIM25, which promoting DDX5 degradation through the ubiquitin-proteasome pathway. In particular, SLC26A4-AS1 inhibited expression of multiple DNA double-strand breaks (DSBs) repair genes, especially genes coding proteins in the MRE11/RAS50/NBS1 (MRN) complex. Enhanced interaction between DDX5 and transcriptional factor E2F1 due to silencing of SLC26A4-AS1 promoted binding of the DDX5-E2F1 complex at promoters of the MRN genes and, thus, stimulate the MRN/ATM dependent DSB signaling and thyroid cancer metastasis. Our study uncovered new insights into the biology driving thyroid cancer metastasis and highlights potentials of lncRNAs as future therapeutic targets again cancer metastasis.

MED13L integrates Mediator-regulated epigenetic control into lung cancer radiosensitivity.

To date, efforts to improve non-small-cell lung cancer (NSCLC) outcomes with increased radiation dose have not been successful. Identification of novel druggable targets that are capable to modulate NSCLC radiosensitivity may provide a way forward. Mediator complex is implicated in gene expression control, but it remains unclear how Mediator dysfunction is involved in cancer radiotherapy. Methods: The biologic functions of miR-4497, MED13L and PRKCA in NSCLC radiosensitivity were examined through biochemical assays including gene expression profilling, cell proliferation assay, colony formation assay, wound healing assay, transwell assay, dual luciferase reporter assay, xenograft models, immunoprecipitation, and chromatin immunoprecipitation sequencing. Clinical implications of miR-4497, MED13L and PRKCA in radiosensitivity were evaluated in NSCLC patients treated with concurrent chemoradiotherapy or radiotherapy alone. Results: We found that radiation can trigger disassemble of Mediator complex via silencing of MED13L by miR-4497 in NSCLC. Although not interrupting structure integrity of the core Mediator or the CDK8 kinase module, suppression of MED13L attenuated their physical interactions and reduced recruitment of acetyltransferase P300 to chromatin via Mediator. Silencing of MED13L therefore diminishes global H3K27ac signals written by P300, activities of enhancer and/or promoters and expression of multiple oncogenes, especially PRKCA. Inhibition of PRKCA expression potentiates the killing effect of radiotherapy in vitro and in vivo. Remarkably, high PRKCA expression in NSCLC tissues is correlated with poor prognosis of patients received radiotherapy. Conclusions: Our study linking PRKCA to radiosensitivity through a novel mechanism may enable the rational targeting of PRKCA to unlock therapeutic potentials of NSCLC.

Identification of Leukocyte telomere length-related genetic variants contributing to predisposition of Esophageal Squamous Cell Carcinoma.

Background: Cancers may arise from cells with dysregulated telomeric functions due to shorten telomere length. We and others previously found that short leukocyte telomere length was associated with markedly evaluated risk of esophageal squamous cell carcinoma (ESCC). Hence, we hypothesized that single nucleotide polymorphisms (SNPs) associated with shorter telomere length may contribute to ESCC predisposition. Methods: We systematically evaluated association between seven candidate seven SNPs (CXCR4 rs6430612, TERT rs13172201, TERT rs10069690, TERT rs2853676, TERT rs451360, OBFC1 rs4387287, and VPS34 rs2162440) and ESCC risk in two case-control sets consisting of 1588 ESCC cases and 1600 controls. Logistic regression models were utilized to estimate associations between SNPs and ESCC susceptibility and odds ratios (ORs) and their 95% confidence intervals (95% CIs) were computed. Results: We firstly identified three SNPs (rs6430612, rs13172201 and rs4387287) which are significantly associated with telomere length in Chinese populations (all P<0.05). Importantly, CXCR4 rs6430612 and OBFC1 rs4387287 polymorphisms significantly confer reduced risk of ESCC (P=1.7×10-7 and P=3.9×10-5). On the contrary, we observed an evidently increased risk for ESCC development associated with TERT rs13172201 genetic variant (P=2.2×10-4). Conclusions: In summary, rs6430612, rs13172201 and rs4387287 might be key genetic components in complicated regulation of telomere length and contributing to ESCC predisposition. Our results elucidate the prevalent involvement of genetic variants in telomere biology and further provide pathogenic insights into the role of telomeres in cancer development.

Noncoding RNAs in gastric cancer: implications for drug resistance.

Gastric cancer is the fourth most common malignancy and the third leading cause of cancer-related deaths worldwide. Advanced gastric cancer patients can notably benefit from chemotherapy including adriamycin, platinum drugs, 5-fluorouracil, vincristine, and paclitaxel as well as targeted therapy drugs. Nevertheless, primary drug resistance or acquisition drug resistance eventually lead to treatment failure and poor outcomes of the gastric cancer patients. The detailed mechanisms involved in gastric cancer drug resistance have been revealed. Interestingly, different noncoding RNAs (ncRNAs), such as microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), are critically involved in gastric cancer development. Multiple lines of evidences demonstrated that ncRNAs play a vital role in gastric cancer resistance to chemotherapy reagents and targeted therapy drugs. In this review, we systematically summarized the emerging role and detailed molecular mechanisms of ncRNAs impact drug resistance of gastric cancer. Additionally, we propose the potential clinical implications of ncRNAs as novel therapeutic targets and prognostic biomarkers for gastric cancer.

Usage of smart devices amongst medical practitioners in Universitas Academic Hospital.

BACKGROUND: There has been a rapid rise in the use of smart devices amongst medical practitioners throughout the world. This study aimed to identify how smart devices were being used by medical practitioners at the Universitas Academic Hospital (UAH), Bloemfontein, and the associated factors thereof. We also identified the views of medical practitioners regarding the usage of smart devices at their workplace. METHODS: A prospective cross-sectional study was conducted. Anonymous questionnaires were distributed to medical practitioners working at UAH during weekly departmental meetings or monthly morbidity and mortality meetings. The following largest departments were included: Surgery, Anaesthetics, Paediatrics, Internal Medicine, Family Medicine, and Obstetrics and Gynaecology. RESULTS: The response rate was 82.7% of those attending the meetings. All the respondents owned a smart device and brought it to their workplace. The most common applications used on these smart devices were that for drug references (65.9%), medical textbooks (63.6%) and medical calculators (58.1%). Significantly larger percentages of doctors aged 21-39 years compared with those aged 40-65 years used drug reference applications and medical calculators. A quarter (24.8%) of respondents communicated with patients through a smart device, 21.7% used an online storage platform to backup patient data, whilst 56.6% used their devices to store and view patient information. More than one-third (36.7%) agreed that smart devices threatened patient confidentiality, but the majority (58.8%) did not agree that these devices hinder patient communication. The majority felt that these devices improved both personal performance (69.2%) and patient care (79.0%). CONCLUSION: Smart devices usage is common in this setting. Hence, integration of such usage in medical curricula, discussion on professionalism, ethics and confidentiality in this context, and guidance from institutions and professional bodies become necessary.

Genetic variations associated with telomere length confer risk of gastric cardia adenocarcinoma.

BACKGROUND: Aberrant telomere lengthening is a critical feature of malignant cells. Short leukocyte telomere length (LTL) confers elevated risk of gastric cardia adenocarcinoma (GCA). Multiple genome-wide association studies (GWAS) identified various single-nucleotide polymorphisms (SNPs) associated with LTL in different ethnic populations. However, it remains largely unexplored how these genetic variants are involved in GCA susceptibility. METHODS: We systematically screened GWAS-identified candidate SNPs and tested the impact of 30 polymorphisms in genes associated with interindividual LTL variation on GCA using two-stage case-control comparisons consisting of 1024 GCA patients and 1118 controls. RESULTS: We observed that CXCR4 rs6430612, TERT rs10069690, and rs2853676 as well as VPS34 rs2162440 are significantly associated with GCA development. A 0.64-fold decreased risk of GCA is associated with the CXCR4 rs6430612 CT genotype compared with the CC genotype (P = 0.002). On the contrary, the TERT rs10069690 TT genotype carriers had a 1.83-fold increased risk to develop GCA compared to the CC genotype carriers (P = 5.8×10-6). We also detected a 2.17-fold increased OR for GCA that was associated with the TERT rs2853676 TT genotype (P = 2.6×10-6). In addition, the odds of having the VPS34 rs2162440 GA genotype in GCA patients were 1.35 compared with the GG genotype (P = 0.002). In stratified analyses, the association between TERT rs10069690 polymorphism and GCA was more pronounced in nonsmokers (Pinteraction = 9.7 × 10-5) and nondrinkers (Pinteraction = 4.6 × 10-5). CONCLUSIONS: Our results highlight the importance of both LTL and LTL-related genetic variants to GCA predisposition.

Ferulic acid and PDMS modified medical carbon materials for artificial joint prosthesis.

Medical carbon material has been extensively studied due to their excellent biological and mechanical properties. However, the dissociation of the surface carbon particles greatly limited the application of medical carbon material (MCM). To overcome this defect, we introduced the polydimethylsiloxane, a polymer-coating material (PCM) that possesses acceptable biocompatibility, into medical carbon material to prevent the shedding of carbon debris. Additionally, to reduce inflammatory reactions and increase surface hydrophilicity, ferulic acid, also called Chinese medicine coating material (CCM), was used to modify the surface of polymer-coating material. We investigated the proliferation and adhesion of NIH-3T3 cells onto MCM, PCM and CCM in vitro. We showed that CCM exhibited excellent biological activity to promote cell growth. Twelve weeks after CCM implantation, bone defects were repaired, and the material showed acceptable chemical stability. The results indicated that the CCM composite possesses excellent mechanical property and favorable biocompatibility, which can be used for clinical bone repair.

DKK3 overexpression attenuates cardiac hypertrophy and fibrosis in an angiotensin-perfused animal model by regulating the ADAM17/ACE2 and GSK-3ß/ß-catenin pathways.

AIMS: Cardiac pressure and humoral factors induce cardiac hypertrophy and fibrosis, which are characterized by increased stiffness, reduced contractility and altered perfusion. Angiotensin II (AngII) is well known to promote this pathology. Angiotensin-converting enzyme (ACE) 2, which cleaves AngII and forms Ang-(1-7), exerts protective anti-hypertrophy and anti-fibrosis effects. A disintegrin and metalloproteinase 17 (ADAM17), a membrane-bound enzyme reported to cleave ACE2, may participate in the pathological process of AngII perfusion-induced heart damage. However, researchers have not clearly determined whether dickkopf-3 (DKK3) regulates the ADAM17/ACE2 pathway and, if so, whether DKK3-mediated regulation is related to the glycogen synthase kinase-3ß (GSK-3ß)/ß-catenin pathway. In this study, we explored whether DKK3 overexpression ameliorates the development of AngII-induced cardiac fibrosis and hypertrophy through the ADAM17/ACE2 and GSK-3ß/ß-catenin pathways. METHODS: Mice were injected with a DKK3-overexpressing adenovirus or vehicle and then infused with AngII or saline using subcutaneously implanted mini-pumps for four weeks. Hearts were stained with hematoxylin-eosin, Masson's trichrome and immunohistochemical markers for histology. Primary fibroblasts were treated with the adenovirus and AngII and then examined using western blotting, EdU (5-ethynyl-2'-deoxyuridine) assays and immunofluorescence. Additionally, siRNA silencing was performed to study the role of DKK3 and the involved pathways. RESULTS: AngII-induced cardiac hypertrophy and interstitial and perivascular fibrosis were less severe in DKK3-overexpressing mice than in control mice. Moreover, the expression levels of fibrotic genes, such as collagen I and III, and the hypertrophic genes atrial natriuretic peptide (ANP) and beta-myosin heavy chain (ß-MHC) were decreased. DKK3 overexpression also exerted a protective effect by inhibiting ADAM17 phosphorylation, thus increasing ACE2 expression and subsequently promoting AngII degradation. Furthermore, this process was mediated by the inhibition of GSK-3ß and ß-catenin and decreased translocation of ß-catenin to the nucleus. On the other hand, the DKK3 knockdown by siRNA achieved opposite results. CONCLUSION: DKK3 overexpression substantially alleviated AngII infusion-induced cardiac hypertrophy and fibrosis by regulating ADAM17/ACE2 pathway activity and inhibiting the GSK-3ß/ß-catenin pathway.

STAT3 Undergoes Acetylation-dependent Mitochondrial Translocation to Regulate Pyruvate Metabolism.

Cytoplasmic STAT3, after activation by growth factors, translocates to different subcellular compartments, including nuclei and mitochondria, where it carries out different biological functions. However, the precise mechanism by which STAT3 undergoes mitochondrial translocation and subsequently regulates the tricarboxylic acid (TCA) cycle-electron transport chain (ETC) remains poorly understood. Here, we clarify this process by visualizing STAT3 acetylation in starved cells after serum reintroduction or insulin stimulation. CBP-acetylated STAT3 undergoes mitochondrial translocation in response to serum introduction or insulin stimulation. In mitochondria, STAT3 associates with the pyruvate dehydrogenase complex E1 (PDC-E1) and subsequently accelerates the conversion of pyruvate to acetyl-CoA, elevates the mitochondrial membrane potential, and promotes ATP synthesis. SIRT5 deacetylates STAT3, thereby inhibiting its function in mitochondrial pyruvate metabolism. In the A549 lung cancer cell line, constitutively acetylated STAT3 localizes to mitochondria, where it maintains the mitochondrial membrane potential and ATP synthesis in an active state.