Nuclear factor (erythroid-derived 2)-like 2 (NRF2) is a master regulator of antioxidant and detoxification activities that can eliminate reactive oxygen species (ROS) produced via irradiation. However Show more
Nuclear factor (erythroid-derived 2)-like 2 (NRF2) is a master regulator of antioxidant and detoxification activities that can eliminate reactive oxygen species (ROS) produced via irradiation. However, Nrf2 overexpression in liver cancer cells may cause both radioresistance and chemoresistance. Reducing Nrf2 levels can enhance the radiosensitivity of HepG2 cells. Wingless/int-3A (Wnt3A) is a Wnt family protein that mainly activates the canonical Wnt signaling pathway. Recent studies showed that the Axin1-GSK-3β protein complex, a component of the canonical Wnt signaling pathway, can capture Nrf2 and facilitate its ubiquitination and proteasomal degradation in the cytoplasm. This protein complex is degraded upon activation of the Wnt signaling pathway. In the present study, we treated HepG2 cells with the Wnt3A inhibitor LGK-974, an effective and specific PORCN inhibitor that can prevent the formation of a proper folding of the Wnt protein in the endoplasmic reticulum. We found that HepG2 cells became more sensitive to radiation with increasing LGK-974 concentrations. Upon 2 Gy or 4 Gy irradiation, the cells treated with LGK-974 more frequently underwent apoptosis and grew less rapidly. PCR and western blot results showed that inhibiting the secretion of Wnt3A blocked the Wnt signaling pathway and prevented Nrf2 signaling. Notably, the Wnt inhibitor may serve as a radiosensitizing drug. Show less
Carbohydrate response element binding protein (ChREBP) is a transcription factor that responds to glucose and activates genes involved in the glycolytic and lipogenic pathways. Recent studies have lin Show more
Carbohydrate response element binding protein (ChREBP) is a transcription factor that responds to glucose and activates genes involved in the glycolytic and lipogenic pathways. Recent studies have linked adipose ChREBP to insulin sensitivity in mice. However, while ChREBP is most highly expressed in the liver, the effect of hepatic ChREBP on insulin sensitivity remains unknown. To clarify the importance of hepatic ChREBP on glucose homeostasis, we have generated a knockout mouse model that lacks this protein specifically in the liver (Liver-ChREBP KO). Using Liver-ChREBP KO mice, we investigated whether hepatic ChREBP deletion influences insulin sensitivity, glucose homeostasis and the development of hepatic steatosis utilizing various dietary stressors. Furthermore, we determined gene expression changes in response to fasted and fed states in liver, white, and brown adipose tissues. Liver-ChREBP KO mice had impaired insulin sensitivity as indicated by reduced glucose infusion to maintain euglycemia during hyperinsulinemic-euglycemic clamps on both chow (25% lower) and high-fat diet (33% lower) (p < 0.05). This corresponded with attenuated suppression of hepatic glucose production. Although Liver-ChREBP KO mice were protected against carbohydrate-induced hepatic steatosis, they displayed worsened glucose tolerance. Liver-ChREBP KO mice did not show the expected gene expression changes in liver in response to fasted and fed states. Interestingly, hepatic ChREBP deletion also resulted in gene expression changes in white and brown adipose tissues, suggesting inter-tissue communication. This included an almost complete abolition of BAT ChREBPβ induction in the fed state (0.15-fold) (p = 0.015) along with reduced lipogenic genes. In contrast, WAT showed inappropriate increases in lipogenic genes in the fasted state along with increased PEPCK1 in both fasted (3.4-fold) and fed (5.1-fold) states (p < 0.0001). Overall, hepatic ChREBP is protective in regards to hepatic insulin sensitivity and whole body glucose homeostasis. Hepatic ChREBP action can influence other peripheral tissues and is likely essential in coordinating the body's response to different feeding states. Show less
Apolipoprotein A5 (apoA5) has been implicated in the formation of hepatocyte lipid droplets, a histological hallmark of non-alcoholic fatty liver disease (NAFLD). Recent evidence demonstrated that liv Show more
Apolipoprotein A5 (apoA5) has been implicated in the formation of hepatocyte lipid droplets, a histological hallmark of non-alcoholic fatty liver disease (NAFLD). Recent evidence demonstrated that liver X receptor α (LXRα), a transcription factor involved in down-regulation of Show less
Ting-Huan Chen, Chen-Yu Chen, Hui-Chin Wen+4 more · 2017 · FASEB journal : official publication of the Federation of American Societies for Experimental Biology · added 2026-04-24
Yes-associated protein (YAP) is a transcriptional coactivator in the Hippo pathway that regulates cell proliferation, differentiation, and apoptosis. The MEK5/ERK5 MAPK cascade is essential for the ea Show more
Yes-associated protein (YAP) is a transcriptional coactivator in the Hippo pathway that regulates cell proliferation, differentiation, and apoptosis. The MEK5/ERK5 MAPK cascade is essential for the early step of myogenesis. In this study, we generated C2C12 stable cell lines that expressed YAP (C2C12-YAP cells) and found that ERK5 and MEK5 were activated in C2C12-YAP cells compared with control C2C12 (C2C12-vector) cells. C2C12-YAP stable cells also differentiated into myotubes better than C2C12-vector cells, and expressed elevated levels of myogenin, a transcription factor that regulates myogenesis, as well as elevated levels of myosin heavy chain, a skeletal muscle marker. Western blot analysis revealed that Src and c-Abl (Abelson murine leukemia viral oncogene homolog 1) activation were enhanced in C2C12-YAP cells. Conversely, treatment of inhibitors of c-Abl, Src, or MEK5 inhibited activation of MEK5 and ERK5 and myogenesis of C2C12 myoblasts. Specific interactions between YAP and proteins in the ERK5 pathway, such as MEK kinase 3 (MEKK3) and ERK5, were illustrated by coimmunoprecipitation experiments. MEKK3 contains the PPGY motif (aa 178-181), which may interact with YAP. Site-directed mutagenesis experiments revealed that expression of MEKK3 Y181F mutant inhibited MEK5/ERK5 activation and myogenic differentiation. These results suggest that YAP promotes muscle differentiation by activating the Abl/Src/MEKK3/MEK5/ERK5 kinase cascade.-Chen, T.-H., Chen, C.-Y., Wen, H.-C., Chang, C.-C., Wang, H.-D., Chuu, C.-P., Chang, C.-H. YAP promotes myogenic differentiation Show less
Identity-by-descent mapping using empirical estimates of identity-by-descent allele sharing may be useful for studies of complex traits in founder populations, where hidden relationships may augment t Show more
Identity-by-descent mapping using empirical estimates of identity-by-descent allele sharing may be useful for studies of complex traits in founder populations, where hidden relationships may augment the inherent genetic information that can be used for localization. Through identity-by-descent mapping, using ≈400 000 single-nucleotide polymorphisms (SNPs), of serum lipid profiles, we identified a major linkage signal for triglycerides in 1007 Pima Indians (LOD=9.23; Show less
Intratumoral hypoxia promotes the distant metastasis of cancer subclones. The clinical expression level of hypoxia-inducible factor-1α (HIF-1α) reflects the prognosis of a variety of cancers, especial Show more
Intratumoral hypoxia promotes the distant metastasis of cancer subclones. The clinical expression level of hypoxia-inducible factor-1α (HIF-1α) reflects the prognosis of a variety of cancers, especially breast cancer. Histone deacetylase (HDAC) inhibitors can target HIF-1α protein due to von Hippel-Lindau (VHL) protein-dependent degradation. Dietary organosulfur compounds, such as those in garlic, have been reported as HDAC inhibitors. The effects of diallyl sulfide (DAS), diallyl disulfide (DADS), and diallyl trisulfide (DATS) on the ratio of firefly/Renilla luciferase activity in hypoxic MDA-MB-231 cells were determined. The mRNA expressions of HIF-1α target genes ANGPTL4, LOXL4, and LOX in hypoxic MDA-MB-231 cells were significantly down-regulated by DATS. DATS attenuated the metastatic potential of MDA-MB-231 cells in hypoxia-induced embryonic zebrafish, xenograft, and orthotopic tumors. Endothelial cell-cancer cell adhesion, wound healing, transwell, and tube formation assays showed that DATS dose-dependently inhibited the migration and angiogenesis of MDA-MB-231 cells in vitro. The expressions of L1CAM, VEGF-A, and EMT-related proteins (Slug, Snail, MMP-2) were inhibited by DATS. DATS dose-dependently inhibited HIF-1α transcriptional activity and hypoxia-induced hematogenous metastasis of MDA-MB-231 cells. It reduced the protein expression of HIF-1α, which did not involve inhibition of HIF-1α mRNA expression or ubiquitin proteasome degradation. Efficient inhibition of HIF-1α expression was required for DATS to resist breast cancer. Show less
The aim of the study is to investigate whether endothelial cells (ECs) promoted the capacity of stem-like cell formation in medulloblastoma (MB) and whether the mechanism of action was associated with Show more
The aim of the study is to investigate whether endothelial cells (ECs) promoted the capacity of stem-like cell formation in medulloblastoma (MB) and whether the mechanism of action was associated with mediation of Notch signaling pathway. Co-culture experiment was conducted to particularly understand the potential role of ECs in promoting phenotype and gene expression of MB stem-like cells. Self-renewal capacity and tumor cell population were measured by sphere-forming assay and flow cytometry, respectively. To further clarify the effects of ECs on the formation of MB stem-like cells, the expression of genes and protein in MB stem-like cells (CCND1, CDK6, c-MYC, and Bmi-1) and Notch (Notch2, Jagged 1, Hes-1, and Hey-2) was quantified by quantitative real-time PCR (qRT-PCR) and western blot, respectively. Also, observed mediation of ECs in regulation of tumor cell stemness by Notch activation was observed when the co-cultures were treated with γ-secretase inhibitor (N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT)). Further investigation was conducted for the effects of ECs on the tumorigenesis in vivo of MB cells when co-cultures were inoculated into a nude mouse after treated with DAPT. Afterwards, tumor size and volume were measured. The sphere-forming rate and cell ratio of stem-like cells were significantly increased. Furthermore, the expression of genes and protein in stem-like cells and Notch was obviously upregulated although treated with γ-secretase inhibitor. Moreover, tumor size and volume were dramatically magnified. This study revealed that Notch pathway activation played a key role in the formation of stem-like cells in MB and had valuable meaning for further investigation of targeted therapies. Show less
We aimed to characterize common genetic variants that influence saturated fatty acid concentrations in East Asians. Meta-analysis of genome-wide association studies for circulating SFAs was conducted Show more
We aimed to characterize common genetic variants that influence saturated fatty acid concentrations in East Asians. Meta-analysis of genome-wide association studies for circulating SFAs was conducted in two population-based cohorts comprising 3521 participants of Chinese ancestry. We identified two novel 14:0-associated loci at LMX1A (LIM homeobox transcription factor 1) and AMPD3 (AMP deaminase 3) (P = 5.08 × 10 To our knowledge, this is the first GWAS analysis to examine SFA concentrations in East Asian populations. Our findings provide novel evidence that genetic variations of several genes from multiple pathways are associated with SFA concentrations in human body. Show less
Insertions and deletions (INDELs) represent a significant fraction of interindividual variation in the human genome yet their contribution to phenotypes is poorly understood. To confirm the quality of Show more
Insertions and deletions (INDELs) represent a significant fraction of interindividual variation in the human genome yet their contribution to phenotypes is poorly understood. To confirm the quality of imputed INDELs and investigate their roles in mediating cardiometabolic phenotypes, genome-wide association and linkage analyses were performed for 15 phenotypes with 1,273,952 imputed INDELs in 1,024 Mexican-origin Americans. Imputation quality was validated using whole exome sequencing with an average kappa of 0.93 in common INDELs (minor allele frequencies [MAFs] ≥ 5%). Association analysis revealed one genome-wide significant association signal for the cholesterylester transfer protein gene (CETP) with high-density lipoprotein levels (rs36229491, P = 3.06 × 10 Show less
Fa Chen, Baochang He, Lingjun Yan+3 more · 2017 · Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons · Elsevier · added 2026-04-24
The fatty acid desaturase 1 (FADS1) gene variant is a novel susceptibility marker for laryngeal squamous cell carcinoma identified by a recent genome-wide association study, but it is still unclear wh Show more
The fatty acid desaturase 1 (FADS1) gene variant is a novel susceptibility marker for laryngeal squamous cell carcinoma identified by a recent genome-wide association study, but it is still unclear whether this genetic variant continues to influence oral cancer recurrence or death. The purpose of this study was to evaluate the role of FADS1 rs174549 polymorphism and its interaction with postoperative chemoradiotherapy in the prognosis of oral cancer. A prospective cohort study involving 304 oral cancer patients with surgical resection was conducted in Fujian, China. Demographic and clinical data (adjuvant therapy types, histologic types, clinical stage, etc.) were extracted from medical records, and follow-up data were obtained by telephone interviews. We collected 5 to 8 mL of venous blood from all patients for DNA extraction, and rs174549 genotypes were determined by TaqMan assays (Life Technologies, Carlsbad, CA). A Cox proportional hazards model and Kaplan-Meier curve were used to assess the association between FADS1 rs174549 polymorphism and progression-free survival (PFS), as well as overall survival, in oral cancer. Carrying the AA genotype was significantly associated with a decreased risk of PFS: The hazard ratio was 0.52 (95% confidence interval, 0.29 to 0.93) for the codominant model and 0.54 (95% confidence interval, 0.31 to 0.94) for the recessive model. Moreover, better PFS was particularly obvious in patients who had received chemoradiotherapy. A positive multiplicative interaction between FADS1 rs174549 polymorphism and chemoradiotherapy was observed for PFS (P = .036). No significant association was found between FADS1 rs174549 polymorphism and overall survival. Our study suggests, for the first time, that FADS1 rs174549 polymorphism is a potentially independent and favorable factor in predicting oral cancer PFS especially for patients who undergo chemoradiotherapy, and it may serve as a potential target for individualized treatment in the future. Show less
Dual specificity phosphatase 6 (DUSP6), a member of the dual specificity protein phosphatase subfamily, can inactivate ERK1/2. However, its possible role in glutamate-induced oxidative cytotoxicity ef Show more
Dual specificity phosphatase 6 (DUSP6), a member of the dual specificity protein phosphatase subfamily, can inactivate ERK1/2. However, its possible role in glutamate-induced oxidative cytotoxicity effects is not clear.Here, we aimed to investigate whether DUSP6 was neuroprotective against glutamate-induced cytotoxicity in HT22 mouse hippocampal cells and primary cultured hippocampal neurons (pc-HNeu). HT22 and pc-HNeu cells were treated with varying concentrations of glutamate (from 0.05mM to 5.0mM) and DUSP6 protein expression were detected by western blotting. DUSP6-overexpressing HT22 and pc-HNeu cells were generated by transfection with DUSP6-overexpressing plasmid. The effects of DUSP6 overexpression on glutamate-induced cytotoxicity, cell death, cell apoptosis, and cell autophagy were determined by cell proliferation assays, flow cytometry, transmission electron microscopy, and western blotting. Glutamate treatment from 0.5mM to 5.0mM downregulated DUSP6 protein expression in both HT22 and pc-HNeu cells. DUSP6 overexpression ameliorated glutamate-induced cell death, apoptosis, and autophagy in both HT22 and pc-HNeu cells. Furthermore, ERK1/2 phosphorylation was decreased by DUSP6 overexpression. In conclusion, DUSP6 has neuroprotective effects against glutamate-induced cytotoxicity in HT22 and pc-HNeu cells. Targeting DUSP6 may be a useful strategy to prevent neuronal death in neurodegenerative diseases including AD. Show less
The HECT E3 ligases ubiquitinate numerous transcription factors and signaling molecules, and their activity must be tightly controlled to prevent cancer, immune disorders, and other diseases. In this Show more
The HECT E3 ligases ubiquitinate numerous transcription factors and signaling molecules, and their activity must be tightly controlled to prevent cancer, immune disorders, and other diseases. In this study, we have found unexpectedly that peptide linkers tethering WW domains in several HECT family members are key regulatory elements of their catalytic activities. Biochemical, structural, and cellular analyses have revealed that the linkers can lock the HECT domain in an inactive conformation and block the proposed allosteric ubiquitin binding site. Such linker-mediated autoinhibition of the HECT domain can be relieved by linker post-translational modifications, but complete removal of the brake can induce hyperactive autoubiquitination and E3 self destruction. These results clarify the mechanisms of several HECT protein cancer associated mutations and provide a new framework for understanding how HECT ubiquitin ligases must be finely tuned to ensure normal cellular behavior. Show less
Exploring the biological functions of long non-coding RNAs (lncRNAs) has come to the foreground in recent years. Studies have indicated that the lncRNA metastasis‑associated lung adenocarcinoma transc Show more
Exploring the biological functions of long non-coding RNAs (lncRNAs) has come to the foreground in recent years. Studies have indicated that the lncRNA metastasis‑associated lung adenocarcinoma transcript 1 (MALAT1) not only regulates tumorigenesis in hepatocellular carcinoma, but also controls cell cycle progression in hematopoietic cells. The present study was designed to investigate the biological role of lncRNA MALAT1 in liver regeneration. We carried out a series of assays during liver regeneration following 2/3 partial hepatectomy in mice. We explored the functions of lncRNA MALAT1 with a series of functional analyses in vitro. We found that MALAT1 was upregulated during liver regeneration. Moreover, MALAT1 accelerated hepatocyte proliferation by stimulating cell cycle progression from the G1 to the S phase and inhibiting apoptosis in vitro. In addition, our findings also demonstrated that MALAT1 was regulated by p53 during liver regeneration, and that p53 may be a key upstream regulator of MALAT1 activity. Mechanistically, we found that MALAT1 activated the Wnt/β‑catenin pathway by inhibiting the expression of Axin1 and adenomatous polyposis coli (APC), and subsequently promoting the expression of cyclin D1. On the whole, the findings of this study suggest that MALAT1 is a critical molecule for liver regeneration. Pharmacological interventions targeting MALAT1 may thus prove to be therapeutically beneficial in liver failure or liver transplantation by promoting liver regeneration. Show less
The aim of this study was to investigate the independent and combined effects of fatty acid desaturase 1 (FADS1) gene polymorphism and fish consumption on oral cancer. A hospital-based case-control st Show more
The aim of this study was to investigate the independent and combined effects of fatty acid desaturase 1 (FADS1) gene polymorphism and fish consumption on oral cancer. A hospital-based case-control study was performed including 305 oral cancer patients and 579 cancer-free controls. The genotypes were determined by TaqMan genotyping assay. Non-conditional logistic regression model was used to assess the effects of FADS1 rs174549 polymorphism and fish intake. Subjects carrying A allele of rs174549 significantly reduced the risk of oral cancer (AA VS GG, OR: 0.65, 95% CI: 0.42-0.99; AA VS AG+GG, OR: 0.67, 95% CI: 0.46-0.98). Moreover, the statistically significant reverse associations were especially evident in men, smokers, alcohol drinkers and those age ≤ 60 years. Additionally, fish intake ≥7 times/week showed a 73% reduction in risk for oral cancer compared to those who ate fish less than 2 times/week (OR: 0.27, 95% CI: 0.18-0.42). Furthermore, a significant gene-diet multiplicative interaction was observed between FADS1 rs174549 polymorphism and fish intake for oral cancer (P=0.028). This preliminary study suggests that FADS1 rs174549 polymorphism and fish consumption may be protective factors for oral cancer, with a gene-diet multiplicative interaction. Functional studies with larger samples are required to confirm our findings. Show less
Colorectal cancer (CRC) is one of the leading cancers worldwide. Surgery is the main therapeutic modality for stage II CRC. However, the implementation of adjuvant chemotherapy remains controversial a Show more
Colorectal cancer (CRC) is one of the leading cancers worldwide. Surgery is the main therapeutic modality for stage II CRC. However, the implementation of adjuvant chemotherapy remains controversial and is not universally applied so far. In this study, we found that the protein expression of lysosomal acid phosphatase 2 (ACP2) was increased in CRC and that stage II CRC patients with high ACP2 expression showed a poorer outcome than those with low ACP2 expression (p = 0.004). To investigate this discrepancy, we analyzed the relation between ACP2 expression and several clinical cofactors.Among patients who received chemotherapy, those with an high expression of ACP2 showed better survival in both stage II and III CRC than those with low ACP2 expression. In stage II CRC patients, univariate analysis showed ACP2 expression and T stage to be cofactors significantly associated with overall survival (ACP2: p = 0.006; T stage: p = 0.034). Multivariate Cox proportion hazard model analysis also revealed ACP2 to be an independent prognostic factor for overall survival (ACP2: p = 0.006; T stage: p = 0.041). Furthermore, ACP2-knockdown CRC cells showed an increase in chemoresistance to 5-FU treatment and increased proliferation marker in the ACP2 knockdown clone.Taken together, our results suggested that ACP2 is an unfavorable prognostic factor for stage II CRC and may serve as a potential chemotherapy-sensitive marker to help identify a subset of stage II and III CRC patients for whom chemotherapy would improve survival.Highlights1. To the best of our knowledge, the study is the first report to show ACP2 overexpression in human colorectal cancer (CRC) and its association with poor outcome in stage II CRC.2. Patients with stage II and III CRCs with high expression of ACP2 were more sensitive to chemotherapy than those with a low expression.3. ACP2 expression may serve as a marker for CRC patients receiving chemotherapy and help identify the subset of CRC patients who would benefit from chemotherapy. Show less
We present molecular cytogenetic characterization of a duplication of 15q24.2-q26.2 associated with anencephaly and neural tube defect (NTD). A 35-year-old pregnant woman was found to have a fetus wit Show more
We present molecular cytogenetic characterization of a duplication of 15q24.2-q26.2 associated with anencephaly and neural tube defect (NTD). A 35-year-old pregnant woman was found to have a fetus with anencephaly by prenatal ultrasound at 12 weeks of gestation. The pregnancy was subsequently terminated, and a malformed fetus was delivered with anencephaly. Cytogenetic analysis of the cultured placental tissues revealed a karyotype of 46,XX,dup(15) (q24.2q26.2). Parental karyotypes were normal. Array comparative genomic hybridization analysis of the placental tissues revealed a 20.36-Mb duplication of 15q24.2-q26.2 encompassing 100 Online Mendelian Inheritance of in Man (OMIM) genes including LINGO1, MTHFS, KIF7 and CHD2. Metaphase fluorescence in situ hybridization analysis using 15q25.1-specidic probe confirmed a duplication of 15q25.1. Polymorphic DNA marker analysis showed a maternal origin of the duplication. A duplication of chromosome 15q24.2-q26.2 can be associated with NTD. Show less
Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a life-threatening condition, and the lipid metabolism disorder is common in the development of this disease. This prospective ob Show more
Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a life-threatening condition, and the lipid metabolism disorder is common in the development of this disease. This prospective observational study aimed to define the characteristics of plasma apolipoprotein A-V (apoA-V) in long-term outcome prediction of HBV-ACLF, and a total of 330 HBV-ACLF patients were included and followed for more than 12 months. In this cohort, the 4-week, 12-week, 24-week and 48-week cumulative mortality of HBV-ACLF was 18.2%(60/330), 50.9%(168/330), 59.7%(197/330) and 63.3%(209/330), respectively. As compared to survivors, the non-survivors had significantly lower concentrations of plasma apoA-V on admission. Plasma apoA-V concentrations were positively correlated with prothrombin time activity (PTA), and negatively correlated with interleukin-10, tumor necrosis factor-α, and iMELD scores. Though plasma apoA-V, PTA, total bilirubin(TBil) and blood urea nitrogen(BUN) were all independent factors to predict one-year outcomes of HBV-ACLF, plasma apoA-V had the highest prediction accuracy. And its optimal cutoff value for one-year survival prediction was 480.00 ng/mL, which had a positive predictive value of 84.68% and a negative predictive value of 92.23%. In summary, plasma apoA-V decreases significantly in non-survivors of HBV-ACLF, and it may be regarded as a new predictive marker for the prognosis of patients with HBV-ACLF. Show less
DExD/H-box helicase 36 (DHX36) is known to be an ATP-dependent RNA helicase that unwinds the guanine-quadruplexes DNA or RNA, but emerging data suggest that it also functions as pattern recognition re Show more
DExD/H-box helicase 36 (DHX36) is known to be an ATP-dependent RNA helicase that unwinds the guanine-quadruplexes DNA or RNA, but emerging data suggest that it also functions as pattern recognition receptor in innate immunity. Porcine reproductive and respiratory syndrome virus (PRRSV) is an Show less
Management of ligament/tendon-to-bone-junction healing remains a formidable challenge in the field of orthopedic medicine to date, due to deficient vascularity and multi-tissue transitional structure Show more
Management of ligament/tendon-to-bone-junction healing remains a formidable challenge in the field of orthopedic medicine to date, due to deficient vascularity and multi-tissue transitional structure of the junction. Numerous strategies have been employed to improve ligament-bone junction healing, including delivery of stem cells, bioactive factors, and synthetic materials, but these methods are often inadequate at recapitulating the complex structure-function relationships at native tissue interfaces. Here, we developed an easily-fabricated and effective biomimetic composite to promote the regeneration of ligament-bone junction by physically modifying the tendon extracellular matrix (ECM) into a Random-Aligned-Random composite using ultrasound treatment. The differentiation potential of rabbit bone marrow stromal cells on the modified ECM were examined in vitro. The results demonstrated that the modified ECM enhanced expression of chondrogenesis and osteogenesis-associated epigenetic genes (Jmjd1c, Kdm6b), transcription factor genes (Sox9, Runx2) and extracellular matrix genes (Col2a1, Ocn), resulting in higher osteoinductivity than the untreated tendon ECM in vitro. In the rabbit anterior cruciate ligament (ACL) reconstruction model in vivo, micro-computed tomography (Micro-CT) and histological analysis showed that the modified Random-Aligned-Random composite scaffold enhanced bone and fibrocartilage formation at the interface, more efficaciously than the unmodified tendon ECM. Therefore, these results demonstrated that the biomimetic Random-Aligned-Random composite could be a promising scaffold for ligament/tendon-bone junction repair. The native transitional region consists of several distinct yet contiguous tissue regions, composed of soft tissue, non-calcified fibrocartilage, calcified fibrocartilage, and bone. A stratified graft whose phases are interconnected with each other is essential for supporting the formation of functionally continuous multi-tissue regions. Various techniques have been attempted to improve adherence of the ligament/tendon graft to bone, including utilization of stem cells, growth factors and biomaterials, but these methods are often inadequate at recapitulating the complex structure-function relationships at native tissue interfaces. Here, we developed an easily-fabricated and effective biomimetic composite to promote the regeneration of ligament-bone junction by physically modifying the tendon extracellular matrix (ECM) into a Random-Aligned-Random composite using ultrasound treatment. The modified ECM enhanced expression of chondrogenesis and osteogenesis-associated epigenetic genes expression in vitro. In the rabbit anterior crucial ligament reconstruction model in vivo, results showed that the modified Random-Aligned-Random composite enhances the bone and fibrocartilage formation in the interface, proving to be more efficient than the unmodified tendon ECM. Therefore, these results demonstrated that the biomimetic Random-Aligned-Random composite could be a promising scaffold for ligament/tendon-bone junction repair. Show less
NRBF2/Atg38 has been identified as the fifth subunit of the macroautophagic/autophagic class III phosphatidylinositol 3-kinase (PtdIns3K) complex, along with ATG14/Barkor, BECN1/Vps30, PIK3R4/p150/Vps Show more
NRBF2/Atg38 has been identified as the fifth subunit of the macroautophagic/autophagic class III phosphatidylinositol 3-kinase (PtdIns3K) complex, along with ATG14/Barkor, BECN1/Vps30, PIK3R4/p150/Vps15 and PIK3C3/Vps34. However, its functional mechanism and regulation are not fully understood. Here, we report that NRBF2 is a fine tuning regulator of PtdIns3K controlled by phosphorylation. Human NRBF2 is phosphorylated by MTORC1 at S113 and S120. Upon nutrient starvation or MTORC1 inhibition, NRBF2 phosphorylation is diminished. Phosphorylated NRBF2 preferentially interacts with PIK3C3/PIK3R4. Suppression of NRBF2 phosphorylation by MTORC1 inhibition alters its binding preference from PIK3C3/PIK3R4 to ATG14/BECN1, leading to increased autophagic PtdIns3K complex assembly, as well as enhancement of ULK1 protein complex association. Consequently, NRBF2 in its unphosphorylated form promotes PtdIns3K lipid kinase activity and autophagy flux, whereas its phosphorylated form blocks them. This study reveals NRBF2 as a critical molecular switch of PtdIns3K and autophagy activation, and its on/off state is precisely controlled by MTORC1 through phosphorylation. Show less
Neuronal regeneration and axonal regrowth mechanisms in the injured mammalian central nervous system are largely unknown. As part of a major pathway for inhibiting axonal regeneration, activated neuro Show more
Neuronal regeneration and axonal regrowth mechanisms in the injured mammalian central nervous system are largely unknown. As part of a major pathway for inhibiting axonal regeneration, activated neuronal glycosylphosphatidylinositol-anchored Nogo receptor (NgR) interacts with LINGO-1 and p75NTR to form a complex at the cell surface. However, it was found in our previous report that upregulation of NgR stimulated by injury plays a key role in neuronal regeneration in the neonatal cortex freeze-lesion model, but its downstream signalling remains elusive. In the present study, the novel regulatory role of NgR in a serine-threonine kinase WNK1 was identified. NgR's transcriptional regulation of WNK1 was identified by RT-qPCR and semiquantitative western blot after the overexpression or knockdown of NgR, and the regulation is specific to WNK1, which is not the same for its family members, WNK2, WNK3 and WNK4. Furthermore, NgR inhibition by NEP fails to affect WNK1, which indicates that WNK1 functions outside of the Nogo-A/NgR pathway. By performing a proliferation, migration and axonal extension assay, we also identified that overexpressed NgR critically regulated these processes and impairment by overexpressing NgR was rescued with coexpression of WNK1, indicating the partial role of WNK1 in NgR-mediated morphological regulation. Our study identifies a separation of functions for the NgR-regulated WNK1 in mediating proliferation, migration and axonal extension in PC12 cells as well as a specific regulatory role between NgR and WNK1 that is important for recovery from central nervous system injury. Show less
A large meta-analysis recently identified six new loci associated with risk of PD, but subsequent studies have given discrepant results. Here we conducted a case-control study in a Han Chinese populat Show more
A large meta-analysis recently identified six new loci associated with risk of PD, but subsequent studies have given discrepant results. Here we conducted a case-control study in a Han Chinese population in an attempt to clarify risk associations in Chinese. Among the four single-nucleotide polymorphisms (SNPs) that we examined - VPS13C-rs2414739, MIR4697-rs329648, GCH1-rs11158026, and SIPA1L2- rs10797576 we detected a significant association between rs329648 and risk of developing PD in a recessive model. This association remained significant after adjusting for gender and age (OR 1.87, 95%CI 1.295-2.694, p=8.21×10 Show less
Alternative splicing provides a major mechanism to generate protein diversity. Increasing evidence suggests a link of dysregulation of splicing associated with cancer. Genome-wide alternative splicing Show more
Alternative splicing provides a major mechanism to generate protein diversity. Increasing evidence suggests a link of dysregulation of splicing associated with cancer. Genome-wide alternative splicing profiling in lung cancer remains largely unstudied. We generated alternative splicing profiles in 491 lung adenocarcinoma (LUAD) and 471 lung squamous cell carcinoma (LUSC) patients in TCGA using RNA-seq data, prognostic models and splicing networks were built by integrated bioinformatics analysis. A total of 3691 and 2403 alternative splicing events were significantly associated with patient survival in LUAD and LUSC, respectively, including EGFR, CD44, PIK3C3, RRAS2, MAPKAP1 and FGFR2. The area under the curve of the receiver-operator characteristic curve for prognostic predictor in NSCLC was 0.817 at 2000 days of overall survival which were also over 0.8 in LUAD and LUSC, separately. Interestingly, splicing correlation networks uncovered opposite roles of splicing factors in LUAD and LUSC. We created prognostic predictors based on alternative splicing events with high performances for risk stratification in NSCLC patients and uncovered interesting splicing networks in LUAD and LUSC which could be underlying mechanisms. Show less
Metabolic syndrome (MetS), a cluster of metabolic disturbances that increase the risk for cardiovascular disease and diabetes, was because of genetic susceptibility and environmental risk factors. To Show more
Metabolic syndrome (MetS), a cluster of metabolic disturbances that increase the risk for cardiovascular disease and diabetes, was because of genetic susceptibility and environmental risk factors. To identify the genetic variants associated with MetS and metabolic components, we conducted a genome-wide association study followed by replications in totally 12,720 participants from the north, north-eastern and eastern China. In combined analyses, independent of the top known signal at rs651821 on APOA5, we newly identified a secondary triglyceride-associated signal at rs180326 on BUD13 (P Show less
Diabetic retinopathy (DR) is a complication of diabetes mellitus (DM) and is the leading cause of vision loss globally. However, the pathogenic mechanism and clinical therapy still needs further impro Show more
Diabetic retinopathy (DR) is a complication of diabetes mellitus (DM) and is the leading cause of vision loss globally. However, the pathogenic mechanism and clinical therapy still needs further improvement. The biologic significance of myocardial infarction associated transcript (MIAT) in DR remains unknown. Here, we aim to explore the mechanism between MIAT and DR, which is essential for RD. Streptozotocin (STZ) was used to induce DM mice and high glucose was used to stimulate cells. ChIP was used to detect the binding activity between nuclear factor κB (NF-κB) and the promoter of the MIAT gene, luciferase activity assay was used to detect the target-specific selectivity between Show less
Spectraplakins are a family of evolutionarily conserved gigantic proteins and play critical roles in many cytoskeleton-related processes. Microtubule actin crosslinking factor 1 (MACF1) is one of the Show more
Spectraplakins are a family of evolutionarily conserved gigantic proteins and play critical roles in many cytoskeleton-related processes. Microtubule actin crosslinking factor 1 (MACF1) is one of the most versatile spectraplakin with multiple isoforms. As a broadly expressed mammalian spectraplakin, MACF1 is important in maintaining normal functions of many tissues. The loss-of-function studies using knockout mouse models reveal the pivotal roles of MACF1 in embryo development, skin integrity maintenance, neural development, bone formation, and colonic paracellular permeability. Mutation in the human MACF1 gene causes a novel myopathy genetic disease. In addition, abnormal expression of MACF1 is associated with schizophrenia, Parkinson's disease, cancer and osteoporosis. This demonstrates the crucial roles of MACF1 in physiology and pathology. Here, we review the research advances of MACF1's roles in specific tissue and in human diseases, providing the perspectives of MACF1 for future studies. Show less
Genome-wide association studies (GWAS) on Parkinson's disease (PD) have mostly been done in Europeans and Japanese. No study has been done in Han Chinese, which make up nearly a fifth of the world pop Show more
Genome-wide association studies (GWAS) on Parkinson's disease (PD) have mostly been done in Europeans and Japanese. No study has been done in Han Chinese, which make up nearly a fifth of the world population. We conducted the first Han Chinese GWAS analysing a total of 22,729 subjects (5,125 PD cases and 17,604 controls) from Singapore, Hong Kong, Malaysia, Korea, mainland China and Taiwan. We performed imputation, merging and logistic regression analyses of 2,402,394 SNPs passing quality control filters in 779 PD cases, 13,227 controls, adjusted for the first three principal components. 90 SNPs with association P < 10-4 were validated in 9 additional sample collections and the results were combined using fixed-effects inverse-variance meta-analysis. We observed strong associations reaching genome-wide significance at SNCA, LRRK2 and MCCC1, confirming their important roles in both European and Asian PD. We also identified significant (P < 0.05) associations at 5 loci (DLG2, SIPA1L2, STK39, VPS13C and RIT2), and observed the same direction of associations at 9 other loci including BST1 and PARK16. Allelic heterogeneity was observed at LRRK2 while European risk SNPs at 6 other loci including MAPT and GBA-SYT11 were non-polymorphic or very rare in our cohort. Overall, we replicate associations at SNCA, LRRK2, MCCC1 and 14 other European PD loci but did not identify Asian-specific loci with large effects (OR > 1.45) on PD risk. Our results also demonstrate some differences in the genetic contribution to PD between Europeans and Asians. Further pan-ethnic meta-analysis with European GWAS cohorts may unravel new PD loci. Show less
Chronic alcohol exposure induces pronounced changes in GPCR-mediated G-protein signaling. Recent microarray and RNA-seq analyses suggest associations between alcohol abuse and the expression of genes Show more
Chronic alcohol exposure induces pronounced changes in GPCR-mediated G-protein signaling. Recent microarray and RNA-seq analyses suggest associations between alcohol abuse and the expression of genes involved in G-protein signaling. The activity of G-proteins (e.g. Gαi/o and Gαq) is negatively modulated by regulator of G-protein signaling (RGS) proteins which are implicated in drugs of abuse including alcohol. The present study used 7days of chronic intermittent ethanol exposure followed by 24h withdrawal (CIE) to investigate changes in mRNA and protein levels of G-protein subunit isoforms and RGS protein subtypes in rat prefrontal cortex, a region associated with cognitive deficit attributed to excessive alcohol drinking. We found that this ethanol paradigm induced differential expression of Gα subunits and RGS subtypes. For example, there were increased mRNA and protein levels of Gαi1/3 subunits and no changes in the expression of Gαs and Gαq subunits in ethanol-treated animals. Moreover, CIE increased the mRNA but not the protein levels of Gαo. Additionally, a modest increase in Gαi2 mRNA level by CIE was accompanied by a pronounced increase in its protein level. Interestingly, we found that CIE increased mRNA and protein levels of RGS2, RGS4, RGS7 and RGS19 but had no effect on the expression of RGS5, RGS6, RGS8, RGS12 or RGS17. Changes in the expression of Gα subunits and RGS subtypes could contribute to the functional alterations of certain GPCRs following chronic ethanol exposure. The present study suggests that RGS proteins may be potential new targets for intervention of alcohol abuse via modification of Gα-mediated GPCR function. Show less
We screened variants on an exome-focused genotyping array in >300,000 participants (replication in >280,000 participants) and identified 444 independent variants in 250 loci significantly associated w Show more
We screened variants on an exome-focused genotyping array in >300,000 participants (replication in >280,000 participants) and identified 444 independent variants in 250 loci significantly associated with total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-C), low-density-lipoprotein cholesterol (LDL-C), and/or triglycerides (TG). At two loci (JAK2 and A1CF), experimental analysis in mice showed lipid changes consistent with the human data. We also found that: (i) beta-thalassemia trait carriers displayed lower TC and were protected from coronary artery disease (CAD); (ii) excluding the CETP locus, there was not a predictable relationship between plasma HDL-C and risk for age-related macular degeneration; (iii) only some mechanisms of lowering LDL-C appeared to increase risk for type 2 diabetes (T2D); and (iv) TG-lowering alleles involved in hepatic production of TG-rich lipoproteins (TM6SF2 and PNPLA3) tracked with higher liver fat, higher risk for T2D, and lower risk for CAD, whereas TG-lowering alleles involved in peripheral lipolysis (LPL and ANGPTL4) had no effect on liver fat but decreased risks for both T2D and CAD. Show less