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
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
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
To analyze the related pathogenicity gene mutations in a sudden death of hypertrophic cardiomyopathy （HCM） on whole exome level. Whole exome sequencing （WES） was been performed on a sudden death case Show more
To analyze the related pathogenicity gene mutations in a sudden death of hypertrophic cardiomyopathy （HCM） on whole exome level. Whole exome sequencing （WES） was been performed on a sudden death case sample with pathological features of HCM by Illumina® Hiseq 2500 platform. Using hg19 as the reference sequences, the sequencing data were analyzed. Suspicious single nucleotide variants （SNV） were screened, and the conservatism and function were analyzed by the software such as PhyloP, PolyPhen-2, SIFT, etc. After screening, a heterozygous mutation C719R was finally identified in the gene The molecular anatomy on whole exome level by second generation sequencing technology can help to define the molecular mechanism of HCM and provide a new mothed and thought for analysis of death cause. 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
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
To investigate the role of microtubule-actin crosslinking factor 1 (MACF1) in the response of glioma cells to temozolomide (TMZ). TMZ was applied to a human gliomablastoma cell line (U87) and changes Show more
To investigate the role of microtubule-actin crosslinking factor 1 (MACF1) in the response of glioma cells to temozolomide (TMZ). TMZ was applied to a human gliomablastoma cell line (U87) and changes in the protein expression and cellular localization were determined with Western blot, RT-PCR, and immunofluorescence. The responses of the cells with MACF1 expression knockdown by RNA interference to TMZ were assessed. TMZ-induced effects on MACF1 expression were also assessed by immunohistochemistry in a nude mouse model bearing human glioblastoma xenografts. TMZ resulted in significantly increased MACF1 expression (by about 2 folds) and changes in its localization in the gliomablastoma cells both in vitro and in vivo (P<0.01). Knockdown of MACF1 reduced the proliferation (by 45%) of human glioma cell lines treated with TMZ (P<0.01). TMZ-induced changes in MACF1 expression was accompanied by cytoskeletal rearrangement. MACF1 may be a potential therapeutic target for glioblastoma. 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
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
Carbamoyl phosphate synthase 1 (CPS1) is the rate-limiting enzyme in the first step of the urea cycle and an indispensable enzyme in the metabolism of human liver. However, CPS1 epigenetic regulation Show more
Carbamoyl phosphate synthase 1 (CPS1) is the rate-limiting enzyme in the first step of the urea cycle and an indispensable enzyme in the metabolism of human liver. However, CPS1 epigenetic regulation involves promoter analysis and the role of liver-enriched transcription factors (LETFs), which is not fully elucidated. In this work, the promoter region of hCPS1 gene was cloned, and its activity was investigated. An LETF, hepatocyte nuclear factor 3-beta (HNF3β), was found to promote the transcriptional expression of CPS1 in liver-derived cell lines. In addition, dual-luciferase reporter assay shows that the essential binding sites of the HNF3β may exist in the oligonucleotide -70 nt to +73 nt. Two putative binding sites are available for HNF3β. Mutation analysis results show that the binding site 2 of HNF3β was effective, and the transcriptional activity of CPS1 promoter significantly decreased after mutation. Electrophoretic mobile shift assay (EMSA) and ChIP assay confirmed that HNF3β can interact with the binding site in the CPS1 promoter region of -70 nt to +73 nt promoter region in vivo and in vitro to regulate the transcription of CPS1. Moreover, HNF3β overexpression enhanced the transcription of CPS1 and consequently improved the mRNA and protein levels of CPS1, whereas the knockdown of HNF3β showed the opposite effects. Finally, urea production in cells was measured, and ammonia detoxification improved significantly in cells after transfection with HNF3β. HNF3β plays a vital role in regulation of CPS1 gene and could promote the metabolism of ammonia by regulating CPS1 expression. Show less
Usnea is a lichen of Usnea diffracta Vain and Usnea longissima Ach, which belongs to the genus Usnea Adans of Usneaceae. Usnea exerts numerous pharmacological activities, while its lipid regulatory ac Show more
Usnea is a lichen of Usnea diffracta Vain and Usnea longissima Ach, which belongs to the genus Usnea Adans of Usneaceae. Usnea exerts numerous pharmacological activities, while its lipid regulatory activities remain unreported. This study aims to evaluate the effects of aqueous and ethanol extracts of Usnea on the regulation of lipid metabolism and to explore the possible mechanism. Hyperlipidemia rat model was established by feeding with high-fat diet for 45days. Therapy rats were intragastrically administered with simvastatin (0.004g/kg/d), Usnea aqueous extract (2.766g/kg/d), or Usnea ethanol extract (2.766g/kg/d) for 20days. Pharmacodynamic effects, including body weight, serum and liver lipid levels, total bile acid (TBA), aspartate aminotransferase (AST), alanine aminotransferase (ALT), liver index, and hepatic morphological changes were evaluated. To explore the mechanisms, the lipase activities and protein expressions related to lipid metabolism were detected. Compared with the model group, aqueous and ethanol extracts of Usnea can slow down the weight gain of rats, significantly reduce the serum levels of total cholesterol, triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and the liver contents of TG, LDL-C, as well as significantly increase the contents of high-density lipoprotein cholesterol in serum. In addition, aqueous and ethanol extracts of Usnea can significantly reduce the serum contents of AST and ALT. Furthermore, ethanol extract of Usnea can also significantly reduce the TBA content in serum and liver index. Liver tissue pathological observation showed that aqueous and ethanol extracts of Usnea can improve cell degeneration to a certain extent. Aqueous and ethanol extracts of Usnea can significantly reduce sterol regulatory element-binding proteins-1c, and liver X receptor α (LXR-α) protein expressions. Furthermore, aqueous extract of Usnea can significantly increase hepatic lipase activity and promote apoprotein A5 (ApoA5) protein expression. These findings strongly suggest that the aqueous and ethanol extracts of Usnea play significant roles in regulating lipid metabolism, and the ethanol extract exhibits higher activity than the aqueous extract. The mechanism of the regulation of lipid metabolism by Usnea aqueous extract may involve the increased ApoA5 protein expression via inhibition of the LXR-α signal pathway; however, the mechanism of the regulation of lipid metabolism by Usnea ethanol extract remains to be further studied. Show less
Xuezhikang (XZK), an extract of Chinese red yeast rice, is recommended as an optimal choice for patients with coronary heart disease (CHD) with markedly elevated triglyceride (TG) levels. This study w Show more
Xuezhikang (XZK), an extract of Chinese red yeast rice, is recommended as an optimal choice for patients with coronary heart disease (CHD) with markedly elevated triglyceride (TG) levels. This study was designed to compare the hypotriglyceridemic effects between XZK and simvastatin. The role of apolipoprotein A5 (apoA5), a key regulator of TG metabolism and a target gene of peroxisome proliferator-activated receptor α (PPARα), was to be identified in XZK-related hypotriglyceridemic actions. For these goals, hypertriglyceridemia of rats was induced by a high-fructose diet. In order to investigate the hypotriglyceridemic effects of XZK and simvastatin on these animals based on an equivalent low-density lipoprotein cholesterol (LDL-C) lowering power, we titrated their doses (XZK 80 mg/kg/d versus simvastatin 1 mg/kg/d) according to plasma LDL-C reduction of rats. Similarly, we titrated the target doses of the two agents (XZK 500 μg/ml versus simvastatin 10 μM) according to hepatocyte LDL receptor expressions, and then compared the effects of the two agents on TG and apoA5 of hepatocytes in vitro. Our results showed that XZK (80 mg/kg/d) had higher hypotriglyceridemic performance than simvastatin (1 mg/kg/d) on these animals albeit their equivalent LDL-C lowering power. Higher plasma apoA5 levels and hepatic apoA5 expressions were observed in rats treated with XZK (80 mg/kg/d) than simvastatin (1 mg/kg/d). Further, XZK (80 mg/kg/d) contributed to higher hepatic PPARα expressions of rats than simvastatin (1 mg/kg/d). Although the two agents led to an equivalent up-regulation of LDL receptors of hepatocytes, more TG reduction and apoA5 elevation were detected in hepatocytes treated with XZK (500 μg/ml) than simvastatin (10 μM). However, PPARα knockdown eliminated the above effects of XZK on hepatocytes. Therefore, our study indicates that XZK has greater hypotriglyceridemic performance than simvastatin in the setting of an equivalent LDL-C lowering power, which is attributed to more apoA5 up-regulation by this agent via the PPARα signaling pathway. 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
With emerging evidence connecting cholesterol dysregulation with disturbed pulmonary homeostasis, we are wondering if diet induced hypercholesterolemia would influence the susceptibility to chemical i Show more
With emerging evidence connecting cholesterol dysregulation with disturbed pulmonary homeostasis, we are wondering if diet induced hypercholesterolemia would influence the susceptibility to chemical induced lung tumorigenesis in mice. Six to eight week-old male C57BL/6J mice were fed with either a high-cholesterol atherogenic diet (HCD) or matching normal diet (ND), respectively. Following 3 weeks diet adapting, a multi-dose intraperitoneal injections of ethyl carbamate (urethane, 1 g/kg body weight) were established and lung tumorigenesis assessments were taken after 15 weeks latency period. Compared to the urethane treated ND-fed mice, the HCD-fed mice exhibited significantly decreased lung tumor multiplicity and attenuated pulmonary inflammation, which including reduced influx of leukocytes and down regulated tumor-promoting cyto-/chemokine profile in bronchoalveolar lavage fluid, decreased TLR2/4 expression and NF-κB activation in the lung. As a sensor regulating intracellular cholesterol homeostasis, nuclear receptor LXR-α was up-regulated significantly in the urethane treated HCD-fed mice lungs compared to the ND-fed mice lungs, accompanied with decreased pulmonary free cholesterol content and suppressed tumor cell proliferation. These results suggested that intrapulmonary cholesterol homeostasis, other than systematic cholesterol level, is important in lung tumorigenesis, and LXR activation might partly contribute to the inhibitory role of atherogenic diet on lung tumorigenesis. Show less
In the intestinal epithelium, the aberrant regulation of cell/cell junctions leads to intestinal barrier defects, which may promote the onset and enhance the severity of inflammatory bowel disease (IB Show more
In the intestinal epithelium, the aberrant regulation of cell/cell junctions leads to intestinal barrier defects, which may promote the onset and enhance the severity of inflammatory bowel disease (IBD). However, it remains unclear how the coordinated behaviour of cytoskeletal network may contribute to cell junctional dynamics. In this report, we identified ACF7, a crosslinker of microtubules and F-actin, as an essential player in this process. Loss of ACF7 leads to aberrant microtubule organization, tight junction stabilization and impaired wound closure in vitro. With the mouse genetics approach, we show that ablation of ACF7 inhibits intestinal wound healing and greatly increases susceptibility to experimental colitis in mice. ACF7 level is also correlated with development and progression of ulcerative colitis (UC) in human patients. Together, our results reveal an important molecular mechanism whereby coordinated cytoskeletal dynamics contributes to cell adhesion regulation during intestinal wound repair and the development of IBD. 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
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
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
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
Quantitative trait loci (QTLs) are widely used as instruments to infer causal risk factors of diseases based on the idea of mendelian randomization. Plasma metabolites can serve as risk factors of can Show more
Quantitative trait loci (QTLs) are widely used as instruments to infer causal risk factors of diseases based on the idea of mendelian randomization. Plasma metabolites can serve as risk factors of cancer, and the heritability of many circulating metabolites was high. We conducted a metabolome-wide association study (MWAS) to systematically investigate the effects of genetic variants on metabolites and lung cancer based on published genome-wide association study (GWASs) and metabolic-QTL (mQTL) study. Then we confirmed the results by subsequent genetic and metabolic validations and inferred the causal relationship between identified metabolites and lung cancer through genetic variant(s). We firstly identified six polyunsaturated fatty acids (PUFAs) represented by rs174548-linked haplotype were significantly associated with lung cancer risk in a Chinese GWAS (2311 cases and 3077 controls). Rs174548 was further confirmed to be associated with lung cancer in 13 821 Europeans and 18 471 Asians (ORmeta = 0.87, Pmeta = 1.76 × 10-15) and the effect was much stronger in females (Pinteraction = 6.00 × 10-4). We next validated rs174548-plasma PUFA association in 253 Chinese subjects (β = -0.57, P = 1.68 × 10-3). Rs174548 was also found associated with FADS1 (the major fatty acid desaturase of identified PUFAs) expression in liver tissues. Taken together, we found that rs174548 was associated with both PUFAs and lung cancer. Because rs174548 was the only mQTL variant of PUFAs reported by previous GWASs and explained a large proportion of heritability, we proposed that plasma PUFAs could be causally associated with lung cancer based on the idea of mendelian randomization. These findings provide a diet-related risk factor and may have important implications for prevention on lung cancer. Show less
CETP (cholesteryl ester transfer protein) plays an important role in lipoprotein metabolism; however, whether inhibition of CETP activity can prevent cardiovascular disease remains controversial. We g Show more
CETP (cholesteryl ester transfer protein) plays an important role in lipoprotein metabolism; however, whether inhibition of CETP activity can prevent cardiovascular disease remains controversial. We generated CETP knockout (KO) rabbits by zinc finger nuclease gene editing and compared their susceptibility to cholesterol diet-induced atherosclerosis to that of wild-type (WT) rabbits. On a chow diet, KO rabbits showed higher plasma levels of high-density lipoprotein (HDL) cholesterol than WT controls, and HDL particles of KO rabbits were essentially rich in apolipoprotein AI and apolipoprotein E contents. When challenged with a cholesterol-rich diet for 18 weeks, KO rabbits not only had higher HDL cholesterol levels but also lower total cholesterol levels than WT rabbits. Analysis of plasma lipoproteins revealed that reduced plasma total cholesterol in KO rabbits was attributable to decreased apolipoprotein B-containing particles, while HDLs remained higher than that in WT rabbits. Both aortic and coronary atherosclerosis was significantly reduced in KO rabbits compared with WT rabbits. Apolipoprotein B-depleted plasma isolated from CETP KO rabbits showed significantly higher capacity for cholesterol efflux from macrophages than that from WT rabbits. Furthermore, HDLs isolated from CETP KO rabbits suppressed tumor necrosis factor-α-induced vascular cell adhesion molecule 1 and E-selectin expression in cultured endothelial cells. These results provide evidence that genetic ablation of CETP activity protects against cholesterol diet-induced atherosclerosis in rabbits. Show less
Gliomas are commonly malignant tumors that arise in the human central nervous system and have a low overall five-year survival rate. Previous studies reported that several members of Rab GTPase family Show more
Gliomas are commonly malignant tumors that arise in the human central nervous system and have a low overall five-year survival rate. Previous studies reported that several members of Rab GTPase family are involved in the development of glioma, and abnormal expression of Rab small GTPases is known to cause aberrant tumor cell behavior. In this study, we characterized the roles of Rab21 (Rab GTPase 21), a member of Rab GTPase family, in glioma cells. The study involved downregulation of Rab21 in two glioma cell lines (T98G and U87) through transfection with specific-siRNA. Experiments using the MTT assay, cell cycle analysis, apoptosis assay, real-time PCR and western blot were performed to establish the expression levels of related genes. The results show that downregulation of Rab21 can significantly inhibit cell growth and remarkably induce cell apoptosis in T98G and U87 cell lines. Silencing Rab21 resulted in significantly increased expression of apoptosis-related proteins (caspase7, Bim and Bax) in glioma cells. We inferred that Rab21 silencing can induce apoptosis and inhibit proliferation in human glioma cells, indicating that Rab21 might act as an oncogene and serve as a novel target for glioma therapy. Show less
MUFAs are unsaturated FAs with one double bond and are derived from endogenous synthesis and dietary intake. Accumulating evidence has suggested that plasma and erythrocyte MUFA levels are associated Show more
MUFAs are unsaturated FAs with one double bond and are derived from endogenous synthesis and dietary intake. Accumulating evidence has suggested that plasma and erythrocyte MUFA levels are associated with cardiometabolic disorders, including CVD, T2D, and metabolic syndrome (MS). Previous genome-wide association studies (GWASs) have identified seven loci for plasma and erythrocyte palmitoleic and oleic acid levels in populations of European origin. To identify additional MUFA-associated loci and the potential functional variant at each locus, we performed ethnic-specific GWAS meta-analyses and trans-ethnic meta-analyses in more than 15,000 participants of Chinese and European ancestry. We identified novel genome-wide significant associations for vaccenic acid at 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
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
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
To investigate whether genetic variations on the estrogen metabolic pathway would be associated with risk of Alzheimer's disease (AD). Cross-sectional study. Individuals were recruited at the Memory C Show more
To investigate whether genetic variations on the estrogen metabolic pathway would be associated with risk of Alzheimer's disease (AD). Cross-sectional study. Individuals were recruited at the Memory Clinic, Queen Mary Hospital, Hong Kong. Chinese individuals with (n = 426) and without (n = 350) AD. All subjects underwent a standardized cognitive assessment and genotyping of four candidate genes on the estrogen metabolic pathway (estrogen receptor α gene (ESR1), estrogen receptor β gene (ESR2), cytochrome P450 19A1 gene (CYP19A1), cytochrome P450 11A1 gene (CYP11A1)). Apart from consistent results showing an association between apolipoprotein (APO)E and AD, strong evidence of disease associations were found for polymorphisms in ESR2 and CYP11A1 based on the entire data set. For ESR2, significant protective effects were found for A alleles of rs4986938 (permuted P = .02) and rs867443 (permuted P = .02). For CYP11A1, significant risk effects were found for G alleles of rs11638442 (permuted P = .03) and rs11632698 (permuted P = .03). Stratifying subjects according to APOE ε4 status, their genetic effects continued to be significant in the APOE ε4-negative subgroup. Associations between CYP11A1 polymorphisms (rs2279357, rs2073475) and risk of AD were detected in women but not men. Further gene-level analysis confirmed the above association between ESR2 and CYP11A1, and pathway-level analysis highlighted the genetic effect of the estrogen metabolic pathway on disease susceptibility (permuted pathway-level P = .03). Consistent with previous biological findings for sex steroid hormones in the central nervous system, genetic alterations on the estrogen metabolic pathway were revealed in the Chinese population. Confirmation of these present findings in an independent population is warranted to elucidate disease pathogenesis and to explore the potential of hormone therapy in the treatment of AD. 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
Hepatic fibrosis may ultimately result in organ failure and death, a reality compounded by the fact that most drugs for liver fibrosis appear to be effective only if given as a prophylactic or early t Show more
Hepatic fibrosis may ultimately result in organ failure and death, a reality compounded by the fact that most drugs for liver fibrosis appear to be effective only if given as a prophylactic or early treatment. In a dimethylnitrosamine-induced liver fibrotic model, aspartate aminotransferase/alanine aminotransferase levels could not precisely distinguish the differences between the initial stage of liver fibrosis and normal control, whereas histological examination indicated that dimethylnitrosamine treatment for two weeks has resulted in hepatic fibrogenesis. Comprehensive proteomics identified 12 proteins mainly associated with the interleukin 6-stimulated inflammatory pathway. Coordinately, cytokine profiles showed that dimethylnitrosamine administration would stimulate various signaling pathways leading to liver fibrosis. Of note, apolipoprotein A4 in serum samples obtained from patients in the early stage of liver fibrosis were significantly increased compared to the healthy controls ( Show less