Yakui Li, Dianqiang Yang, Na Tian+12 more · 2019 · The Journal of biological chemistry · American Society for Biochemistry and Molecular Biology · added 2026-04-24
The glucose-responsive transcription factor carbohydrate response element-binding protein (ChREBP) critically promotes aerobic glycolysis and cell proliferation in colorectal cancer cells. It has been Show more
The glucose-responsive transcription factor carbohydrate response element-binding protein (ChREBP) critically promotes aerobic glycolysis and cell proliferation in colorectal cancer cells. It has been reported that ubiquitination may be important in the regulation of ChREBP protein levels and activities. However, the ChREBP-specific E3 ligase and molecular mechanism of ChREBP ubiquitination remains unclear. Using database exploration and expression analysis, we found here that levels of the E3 ligase SMURF2 (Smad-ubiquitination regulatory factor 2) negatively correlate with those of ChREBP in cancer tissues and cell lines. We observed that SMURF2 interacts with ChREBP and promotes ChREBP ubiquitination and degradation via the proteasome pathway. Interestingly, ectopic SMURF2 expression not only decreased ChREBP levels but also reduced aerobic glycolysis, increased oxygen consumption, and decreased cell proliferation in colorectal cancer cells. Moreover, SMURF2 knockdown increased aerobic glycolysis, decreased oxygen consumption, and enhanced cell proliferation in these cells, mostly because of increased ChREBP accumulation. Furthermore, we identified Ser/Thr kinase AKT as an upstream suppressor of SMURF2 that protects ChREBP from ubiquitin-mediated degradation. Taken together, our results indicate that SMURF2 reduces aerobic glycolysis and cell proliferation by promoting ChREBP ubiquitination and degradation via the proteasome pathway in colorectal cancer cells. We conclude that the SMURF2-ChREBP interaction might represent a potential target for managing colorectal cancer. Show less
Mono-2-ethylhexyl phthalate (MEHP) is a major bioactive metabolite in the widely used industrial plasticizer diethylhexyl phthalate (DEHP) that has been found to be toxic to the liver. The aim of this Show more
Mono-2-ethylhexyl phthalate (MEHP) is a major bioactive metabolite in the widely used industrial plasticizer diethylhexyl phthalate (DEHP) that has been found to be toxic to the liver. The aim of this study is to determine whether MEHP exposure can change the expression of fatty acid metabolism-related genes in HepG2 cells, which might be related to non-alcoholic fatty liver disease (NAFLD). The results revealed that exposure to MEHP promoted lipid accumulation in HepG2 cells. The levels of intracellular triglycerides in the hepatocytes increased after exposure to 0.8-100 μM MEHP for 24 h and 48 h. The genetic expressions of SREBP-1c, ChREBP, ACC1, FASN, and SCD significantly increased at 6 h after exposure to MEHP. At 24 h, the expression of the SREBP-1c and ChREBP genes remained increased, while the expression of the FASN and SCD genes decreased. At 48 h, the expression of SREBP-1c, ChREBP, ACC1, FASN, and SCD decreased. Furthermore, the levels of proteins including ACC1, FASN, SCD, and ChREBP (except SREBP-1c) increased at 24 h. These findings suggest that MEHP exposure can promote fatty acid synthesis in hepatocytes by regulating the expression of relevant genes and proteins, contributing to NAFLD. Show less
Understanding the signaling mechanisms that control brown adipose tissue (BAT) development is relevant to understanding energy homeostasis and obesity. The AKT kinases are insulin effectors with criti Show more
Understanding the signaling mechanisms that control brown adipose tissue (BAT) development is relevant to understanding energy homeostasis and obesity. The AKT kinases are insulin effectors with critical in vivo functions in adipocytes; however, their role in adipocyte development remains poorly understood. The goal of this study was to investigate AKT function in BAT development. We conditionally deleted Akt1 and Akt2 either individually or together with Myf5-Cre, which targets early mesenchymal precursors that give rise to brown adipocytes. Because Myf5-Cre also targets skeletal muscle and some white adipocyte lineages, comparisons were made between AKT function in BAT versus white adipose tissue (WAT) and muscle development. We also deleted both Akt1 and Akt2 in mature brown adipocytes with Ucp1-Cre or Ucp1-CreER to investigate AKT1/2 signaling in BAT maintenance. AKT1 and AKT2 are individually dispensable in Myf5-Cre lineages in vivo for establishing brown and white adipocyte precursor cell pools and for their ability to differentiate (i.e. induce PPARγ). AKT1 and AKT2 are also dispensable for skeletal muscle development, and AKT3 does not compensate in either the adipocyte or muscle lineages. In contrast, AKT2 is required for adipocyte lipid filling and efficient downstream AKT substrate phosphorylation. Mice in which both Akt1 and Akt2 are deleted with Myf5-Cre lack BAT but have normal muscle mass, and doubly deleting Akt1 and Akt2 in mature brown adipocytes, either congenitally (with Ucp1-Cre), or inducibly in older mice (with Ucp1-CreER), also ablates BAT. Mechanistically, AKT signaling promotes adipogenesis in part by stimulating ChREBP activity. AKT signaling is required in vivo for BAT development but dispensable for skeletal muscle development. AKT1 and AKT2 have both overlapping and distinct functions in BAT development with AKT2 being the most critical individual isoform. AKT1 and AKT2 also have distinct and complementary functions in BAT maintenance. Show less
Epigenetic alternation is a common contributing factor to neoplastic transformation. Although previous studies have reported a cluster of aberrant promoter methylation changes associated with silencin Show more
Epigenetic alternation is a common contributing factor to neoplastic transformation. Although previous studies have reported a cluster of aberrant promoter methylation changes associated with silencing of tumor suppressor genes, little is known concerning their sequential DNA methylation changes during the carcinogenetic process. The aim of the present study was to address a genome-wide search for identifying potentially important methylated changes and investigate the onset and pattern of methylation changes during the progression of colorectal neoplasia. A three-phase design was employed in this study. In the screening phase, DNA methylation profile of 12 pairs of colorectal cancer (CRC) and adjacent normal tissues was analyzed by using the Illumina MethylationEPIC BeadChip. Significant CpG sites were selected based on a cross-validation analysis from The Cancer Genome Atlas (TCGA) database. Methylation levels of candidate CpGs were assessed using pyrosequencing in the training dataset (tumor lesions and adjacent normal tissues from 46 CRCs) and the validation dataset (tumor lesions and paired normal tissues from 13 hyperplastic polyps, 129 adenomas, and 256 CRCs). A linear mixed-effects model was used to examine the incremental changes of DNA methylation during the progression of colorectal neoplasia. The comparisons between normal and tumor samples in the screening phase revealed an extensive CRC-specific methylomic pattern with 174,006 (21%) methylated CpG sites, of which 22,232 (13%) were hyermethylated and 151,774 (87%) were hypomethylated. Hypermethylation mostly occurred in CpG islands with an overlap of gene promoters, while hypomethylation tended to be mapped far away from functional regions. Further cross validation analysis from TCGA dataset confirmed 265 hypermethylated promoters coupling with downregulated gene expression. Among which, hypermethylated changes in MEEPD2 promoter was successfully replicated in both training and validation phase. Significant hypermethylation appeared since precursor lesions with an extensive modification in CRCs. The linear mixed-effects modeling analysis found that a cumulative pattern of MPPED2 methylation changes from normal mucosa to hyperplastic polyp to adenoma, and to carcinoma (P < 0.001). Our findings indicate that epigenetic alterations of MPPED2 promoter region appear sequentially during the colorectal neoplastic progression. It might be able to serve as a promising biomarker for early diagnosis and stage surveillance of colorectal tumorigenesis. Show less
Ventricular septal defect (VSD) is a fatal congenital heart disease showing severe consequence in affected infants. Early diagnosis plays an important role, particularly through genetic variants. Exis Show more
Ventricular septal defect (VSD) is a fatal congenital heart disease showing severe consequence in affected infants. Early diagnosis plays an important role, particularly through genetic variants. Existing panel-based approaches of variants mining suffer from shortage of large panels, costly sequencing, and missing rare variants. Although a trio-based method alleviates these limitations to some extent, it is agnostic to novel mutations and computational intensive. Considering these limitations, we are studying a novel variants mining algorithm from trio-based sequencing data and apply it on a VSD trio to identify associated mutations. Our approach starts with irrelevant Show less
There is a lack of understanding surrounding the molecular mechanisms involved in the development of chicken skeletal muscle in the late postnatal stage, especially in the regulation of breast muscle Show more
There is a lack of understanding surrounding the molecular mechanisms involved in the development of chicken skeletal muscle in the late postnatal stage, especially in the regulation of breast muscle development related genes, pathways, miRNAs and other factors. In this study, 12 cDNA libraries and 4 small RNA libraries were constructed from Gushi chicken breast muscle samples from 6, 14, 22, and 30 weeks. A total of 15,508 known transcripts, 25,718 novel transcripts, 388 known miRNAs and 31 novel miRNAs were identified by RNA-seq in breast muscle at the four developmental stages. Through correlation analysis of miRNA and mRNA expression profiles, it was found that 417, 370, 240, 1,418, 496, and 363 negatively correlated miRNA-mRNA pairs of Show less
To investigate the mechanism of the combined effects of chlorogenic acid (CGA) and caffeine on lipid metabolism in high-fat diet-induced obese mice, eighty female ICR mice were randomly divided into e Show more
To investigate the mechanism of the combined effects of chlorogenic acid (CGA) and caffeine on lipid metabolism in high-fat diet-induced obese mice, eighty female ICR mice were randomly divided into eight groups and fed with a high-fat diet with/without CGA and/or caffeine for 14 weeks. The combination of CGA and caffeine effectively decreased body weight gain, intraperitoneal adipose tissue weight, serum LDL-c, FFA, TC, TG, leptin, IL-6 concentrations, and hepatic TG and TC levels and increased the serum adiponectin level. The CGA and caffeine combination also promoted the phosphorylation of AMPKα, inhibited the expressions of transcriptional regulators (SREBP-1c and LXRα), and decreased the expressions of FAS and HMGR. Besides, the expressions of ACO, ATGL and HSL were increased by the CGA and caffeine combinations. The results indicated that the combination of CGA and caffeine had anti-obesity effects and regulated lipid metabolism in high-fat diet-induced obese mice via the AMPKα-LXRα/SREBP-1c signaling pathway. Thus, chronic CGA and caffeine intakes may be potent for preventing obesity. Show less
Niacin is currently the most effective drug that increases HDL‑C levels. Apolipoprotein M (ApoM) in humans is mainly found in plasma high‑density lipoprotein (HDL). Little is known about the role play Show more
Niacin is currently the most effective drug that increases HDL‑C levels. Apolipoprotein M (ApoM) in humans is mainly found in plasma high‑density lipoprotein (HDL). Little is known about the role played by niacin in ApoM expression. In this study, the effects of niacin on ApoM expression were assessed as well as the associated mechanism. Human liver cancer cell line HepG2 was treated with niacin alone or with liver X receptor‑α (LXRα) inhibitor at multiple concentrations. The mRNA and protein expression of ApoM were assessed by qRT‑PCR and western blotting. Specific LXRα shRNA was transfected into HepG2 cells to further evaluate the regulatory effects of LXRα on ApoM. An in vivo model was also established to investigate the LXRα inhibitor on the mouse ApoM levels. The comparisons among groups were evaluated using one‑way ANOVA and Student‑Newman‑Keuls test. It was revealed that in HepG2 cells, niacin dose‑dependently increased ApoM gene and protein expression levels. Niacin‑induced upregulation of ApoM was attenuated by an LXRα inhibitor or LXRα shRNA, indicating that LXRα mediated this effect. Moreover, niacin treatment resulted in increased LXRα mRNA levels, in vivo and in vitro; niacin treatment resulted in increased ApoM gene and protein expression levels in mice. In conclusion, niacin upregulates ApoM expression by increasing LXRα expression in vivo and in vitro. Show less
Atherosclerosis is characterized by the accumulation of excess cholesterol in plaques. Reverse cholesterol transport (RCT) plays a key role in the removal of cholesterol. In the present study, we exam Show more
Atherosclerosis is characterized by the accumulation of excess cholesterol in plaques. Reverse cholesterol transport (RCT) plays a key role in the removal of cholesterol. In the present study, we examined the effect of thioredoxin-1 (Trx-1) on RCT and explored the underlying mechanism. We found that Trx-1 promoted RCT in vivo, as did T0901317, a known liver X receptor (LXR) ligand. T0901317 also inhibited the development of atherosclerotic plaques but promoted liver steatosis. Furthermore, Trx-1 promoted macrophage cholesterol efflux to apoAI in vitro. Mechanistically, Trx-1 promoted nuclear translocation of LXRα and induced the expression of ATP-binding cassette transporter A1 (ABCA1). Apolipoprotein E knockout (apoE-/-) mice fed an atherogenic diet were daily injected intraperitoneally with saline or Trx-1 (0.33 mg/kg). Trx-1 treatment significantly inhibited the development of atherosclerosis and induced the expression of ABCA1 in macrophages retrieved from apoE-/- mice. Moreover, the liver steatosis was attenuated by Trx-1. Overall, we demonstrated that Trx-1 promotes RCT by upregulating ABCA1 expression through induction of nuclear translocation of LXRα, and protects liver from steatosis. Show less
In bovine mammary tissue and cells, liver X receptor (LXR) regulates lipid synthesis mainly via transactivation of the transcription factor sterol regulatory element binding protein 1 (SREBP1). In the Show more
In bovine mammary tissue and cells, liver X receptor (LXR) regulates lipid synthesis mainly via transactivation of the transcription factor sterol regulatory element binding protein 1 (SREBP1). In the present work, we investigated the role of LXR in controlling lipid synthesis via transactivation of SREBP1 in goat primary mammary cells (GMEC). The GMEC were treated with a synthetic agonist of LXR, T0901317, and transactivation and transcription of SREBP1, expression of lipogenic genes, and fatty acid profiling and triacylglycerol (TAG) content of the cells were measured. A mild increase in the mRNA expression level of LXRα (NR1H3) was observed following treatment with different concentrations of T0901317, and a dose-dependent increase in mRNA and transactivation of SREBP1 was detected. Activation of LXR resulted in a significant increase in the mRNA expression of most of the measured genes related to de novo synthesis, desaturation, and transport of fatty acids; TAG synthesis; and transcription regulators. Compared with the control, total content of cellular TAG increased by more than 20% with T0901317 treatment. Furthermore, addition of T0901317 increased the proportion of unsaturated fatty acids (e.g., C16:1, C18:1, C20:1, and C22:1), and decreased the proportion of saturated fatty acids (e.g., C16:0, C18:0, C20:0, and C22:0). These results provide evidence that LXR regulates the expression and activity of SREBP1. Our results indicated that LXR participate in regulating the transcription of genes involved in milk fat synthesis in GMEC in an SREBP1-dependent fashion. Show less
Our study aimed to investigate the expression of NR1H3 in endometrial carcinoma, its effect on the proliferation of endometrial carcinoma cells in vitro, and the underlying mechanism of this effect. I Show more
Our study aimed to investigate the expression of NR1H3 in endometrial carcinoma, its effect on the proliferation of endometrial carcinoma cells in vitro, and the underlying mechanism of this effect. Immunohistochemistry of paraffin-embedded, sectioned specimens and of a tissue microarray was conducted to estimate the expression of NR1H3 (liver X receptors α: LXRα) and NR1H2 (liver X receptors β: LXRβ) in endometrial carcinoma tissues. The subcellular localization of NR1H3 in the endometrial carcinoma cell line Ishikawa was determined by immunofluorescence. An agonist of NR1H3, TO901317, was then administered to activate the expression of NR1H3, and cell viability and cell-cycle progression were investigated through MTT and flow cytometric assays, respectively. The gene and protein expression levels of NR1H3, cyclin D1 (CCND1), and cyclin E (CCNE) in cells pretreated with different concentrations of TO901317 for different periods of time were also detected by real-time RT-PCR and Western blot, respectively. The results showed that, in contrast to NR1H2, which was expressed at low levels in endometrial tissues, NR1H3 was upregulated in endometrial adenocarcinoma tissues compared to levels in normal endometrial tissues and endometrial polyps. Moreover, NR1H3 was mainly expressed in the cytoplasm of Ishikawa cells. TO901317 significantly decreased cell viability and arrested the cell cycle in Ishikawa cells in a dose- and time-dependent manner. Furthermore, the administration of TO901317 not only promoted the expression of NR1H3 but also inhibited the expression of CCND1 and CCNE in Ishikawa cells. We demonstrated that NR1H3 is upregulated in endometrial adenocarcinoma and that it inhibits cell viability by inhibiting the expression of CCND1 and CCNE in endometrial carcinoma cells. Our study indicates that NR1H3 may play a role in the development of endometrial cancer and may emerge as a promising therapeutic target. Show less
Total flavones of Epimedium (TFE) is the main active ingredient in Herba Epimedii, which is a well-known Chinese herbal medicine that is widely used to treat certain age-related diseases in oriental c Show more
Total flavones of Epimedium (TFE) is the main active ingredient in Herba Epimedii, which is a well-known Chinese herbal medicine that is widely used to treat certain age-related diseases in oriental countries. The aim of this work was to investigate the anti-aging properties of TFE related to lipid metabolism. Both transcriptomics and metabonomics were applied in this work to investigate the anti-aging properties of TFE. Microarray and LC-MS analysis were conducted on liver samples of three groups of rats, including young (4 months), old (24 months), and old rats administrated TFE. Transcriptomics analysis highlighted 287 transcripts related to the anti-aging effect of TFE, in which the expression ratio of 18 genes regulating lipid metabolism, including HMGCS1 and NR1H3, returned to normal levels after TFE treatment. In addition, 24 aging-related metabolites were discovered in a metabonomics study, and 15 of these were structurally identified, including palmitic amide, linoleamide, and oleamide. Bioinformatics and integral data analysis on the results of the transcriptomics and metabonomics suggest the involvement of 12 key metabolic pathways, half of which are highly related to lipid metabolism. This study demonstrates that the role played by TFE in the lipid metabolism of aging rats is multifaceted and multi-layered. Show less
Primary cardiac diffuse large B cell lymphoma (PC-DLBCL) is a rare kind of hematological malignancy, and its clinical and pathologic characteristics, especially in Eastern countries, remain unclear. M Show more
Primary cardiac diffuse large B cell lymphoma (PC-DLBCL) is a rare kind of hematological malignancy, and its clinical and pathologic characteristics, especially in Eastern countries, remain unclear. Moreover, genomic alterations in PC-DLBCL have not been studied previously. We describe a case of a 57-year-old man who presented with exertional dyspnoea due to a heart mass in April 2018 and was diagnosed with PC-DLBCL characterized by immunohistochemical markers of the activated B cell (ABC) subtype and double expression of c-MYC and Bcl-2. Mutations in a total of 11 genes- Show less
Shipeng Gong, Yongning Chen, Fanliang Meng+4 more · 2019 · FASEB journal : official publication of the Federation of American Societies for Experimental Biology · added 2026-04-24
Currently, cisplatin (DDP) is the first-line chemotherapeutic agent used for treatment of ovarian cancer, but gradually acquired drug resistance minimizes its therapeutic outcomes. We aimed to identif Show more
Currently, cisplatin (DDP) is the first-line chemotherapeutic agent used for treatment of ovarian cancer, but gradually acquired drug resistance minimizes its therapeutic outcomes. We aimed to identify crucial genes associated with DDP resistance in ovarian cancer and uncover potential mechanisms. Two sets of gene expression data were downloaded from Gene Expression Omnibus, and bioinformatics analysis was conducted. In our study, the differentially expressed genes between DDP-sensitive and DDP-resistant ovarian cancer were screened in GSE15709 and GSE51373 database, and chromosome condensation 2 regulator (RCC2) and nucleoporin 160 were identified as 2 genes that significantly up-regulated in DDP-resistant ovarian cancer cell lines compared with DDP-sensitive cell lines. Moreover, RCC2, Ral small GTPase (RalA), and Ral binding protein-1 (RalBP1) expression was found to be significantly higher in DDP-resistant ovarian cancer tissues than in DDP-sensitive tissues. RCC2 plays a positive role in cell proliferation, apoptosis, and migration in DDP-resistant ovarian cancer cell lines in vitro and in vivo. Furthermore, RCC2 could interact with RalA, thus promoting its downstream effector RalBP1. RalA knockdown could reverse the effects of RCC2 overexpression on DDP-resistant ovarian cancer cell proliferation, apoptosis, and migration. Similarly, RalA overexpression could alleviate the effects of RCC2 knockdown in DDP-resistant ovarian cancer cells. Taken together, RCC2 may function as an oncogene, regulating the RalA signaling pathway, and intervention of RCC2 expression might be a promising therapeutic strategy for DDP-resistant ovarian cancer.-Gong, S., Chen, Y., Meng, F., Zhang, Y., Wu, H., Li, C., Zhang, G. RCC2, a regulator of the RalA signaling pathway, is identified as a novel therapeutic target in cisplatin-resistant ovarian cancer. Show less
EMT allows a polarized epithelium to lose epithelial integrity and acquire mesenchymal characteristics. Previously, we found that overexpression of the intracellular domain of Notch3 (N3ICD) can inhib Show more
EMT allows a polarized epithelium to lose epithelial integrity and acquire mesenchymal characteristics. Previously, we found that overexpression of the intracellular domain of Notch3 (N3ICD) can inhibit EMT in breast cancer cells. In this study, we aimed to elucidate the influence of N3ICD or N3ICD combined with the transmembrane domain (TD+N3ICD) on the expression and distribution of TJs/AJs and polar molecules. We found that although N3ICD can upregulate the expression levels of the above-mentioned molecules, TD+N3ICD can inhibit EMT more effectively than N3ICD alone. TD+N3ICD overexpression upregulated the expression of endogenous full-length Notch3 and contributed to correcting the position of TJs/AJs molecules and better acinar structures formation. Co-immunoprecipitation results showed that the upregulated endogenous full-length Notch3 could physically interact with E-ca in MDA-MB-231/pCMV-(TD+N3ICD) cells. Collectively, our data indicate that overexpression of TD+N3ICD can effectively inhibit EMT, resulting in better positioning of TJs/AJs molecules and cell-cell adhesion in breast cancer cells. Show less
Yanjun Li, Yingyu Chen · 2019 · Advances in experimental medicine and biology · Springer · added 2026-04-24
AMPK is an evolutionarily conserved serine/threonine-protein kinase that acts as an energy sensor in cells and plays a key role in the upregulation of catabolism and inactivation of anabolism. Under v Show more
AMPK is an evolutionarily conserved serine/threonine-protein kinase that acts as an energy sensor in cells and plays a key role in the upregulation of catabolism and inactivation of anabolism. Under various physiological and pathological conditions, AMPK can be phosphorylated by an upstream kinase and bind to AMP or ADP rather than ATP, leading to its activation. Activated AMPK regulates a variety of metabolic processes, including autophagy. AMPK promotes autophagy directly by phosphorylating autophagy-related proteins in the mTORC1, ULK1, and PIK3C3/VPS34 complexes or indirectly by regulating the expression of autophagy-related genes downstream of transcription factors such as FOXO3, TFEB, and BRD4. AMPK can also upregulate the autophagic degradation of mitochondria (mitophagy), as it can induce fragmentation of damaged mitochondria in the network and promote the translocation of the autophagy machinery to damaged mitochondria. In this section, we will detail the molecular structure of AMPK, how its activity is regulated, and its pivotal role in regulating autophagy and mitophagy. Show less
Recently, inhibitor of apoptosis proteins (IAPs) and some IAP antagonists were found to regulate autophagy, but the underlying mechanisms remain unclear. WX20120108 is an analogue of GDC-0152 (a known Show more
Recently, inhibitor of apoptosis proteins (IAPs) and some IAP antagonists were found to regulate autophagy, but the underlying mechanisms remain unclear. WX20120108 is an analogue of GDC-0152 (a known IAP antagonist) and displays more potent anti-tumor and autophagy-regulating activity in tumor cells, we investigated the regulatory mechanisms underlying WX20120108-induced autophagy. Using molecular docking and fluorescence polarization anisotropy (FPA) competitive assay, we first demonstrated that WX20120108, acting as an IAP antagonist, bound to the XIAP-BIR3, XIAP BIR2-BIR3, cIAP1 BIR3, and cIAP2 BIR3 domains with high affinities. In six cancer cell lines, WX20120108 inhibited the cell proliferation with potencies two to ten-fold higher than that of GDC-0152. In HeLa and MDA-MB-231 cells, WX20120108 induced caspase-dependent apoptosis and activated TNFα-dependent extrinsic apoptosis. On the other hand, WX20120108 induced autophagy in HeLa and MDA-MB-231 cells in dose- and time-dependent manners. We revealed that WX20120108 selectively activated Foxo3, evidenced by Foxo3 nuclear translocation in both gene modified cell line and HeLa cells, as well as the upregulated expression of Foxo3-targeted genes (Bnip3, Pik3c3, Atg5, and Atg4b), which played a key role in autophagy initiation. WX20120108-induced autophagy was significantly suppressed when Foxo3 gene was silenced. WX20120108 dose-dependently increased the generation of reactive oxygen species (ROS) in HeLa cells, and WX20120108-induced Foxo3 activation was completely blocked in the presence of catalase, a known ROS scavenger. However, WX20120108-induced ROS generation was not affected by cIAP1/2 or XIAP gene silencing. In conclusion, WX20120108-induced autophagy relies on activating ROS-Foxo3 pathway, which is independent of IAPs. This finding provides a new insight into the mechanism of IAP antagonist-mediated regulation of autophagy. Show less
Beneficial effects of low-intensity pulsed ultrasound(US) have been reported for knee articular cartilage injury. It is unclear whether the same effect could be observed on mandibular condylar cartila Show more
Beneficial effects of low-intensity pulsed ultrasound(US) have been reported for knee articular cartilage injury. It is unclear whether the same effect could be observed on mandibular condylar cartilage. This study was designed to explore the efficacy of ultrasound cartilage repair via autophagy regulation. A total of 18 adult rabbits were divided into a sham operation group (exposure to condylar articular surface only), operation without US group (only cartilage surgery), and operation with US group (received ultrasonic therapy daily on day 4 after cartilage surgery). The rabbits were then sacrificed to construct a temporomandibular joint (TMJ) cartilage injury model and HE staining was conducted to observe pathological changes of cartilage in each group. Expression of FGF18, FGFR4, beclin1, ATG3 and ATG7 in rabbit TMJ cartilage were detected using RT-PCR and western blotting. Finally, protein-protein interaction (PPI) analysis was used to observe the interaction among the network of important biomarkers in this injury model. Compared to the operation without US group, the severity of cartilage injury was decreased in the operation with US group according to HE staining. The expression of autophagy biomarkers, beclin1, ATG3, ATG7, FGF18 and FGFR4, in operation with US group were up-regulated compared with those in sham operation group and operation without US group p < 0.05). In PPI analysis, ATG3, ATG7, PIK3C3, PIK3R4, BECN1 were identified as hub nodes connecting with most proteins network. Our results suggest US has therapeutic potential for the treatment of mandibular condylar cartilage injury, and may affect chondrocyte autophagy. Show less
Pulmonary arterial hypertension (PAH) is a life-threatening disease without effective therapies. PAH is associated with a progressive increase in pulmonary vascular resistance and irreversible pulmona Show more
Pulmonary arterial hypertension (PAH) is a life-threatening disease without effective therapies. PAH is associated with a progressive increase in pulmonary vascular resistance and irreversible pulmonary vascular remodeling. SUMO1 (small ubiquitin-related modifier 1) can bind to target proteins and lead to protein SUMOylation, an important post-translational modification with a key role in many diseases. However, the contribution of SUMO1 to PAH remains to be fully characterized. In this study, we explored the role of SUMO1 in the dedifferentiation of vascular smooth muscle cells (VSMCs) involved in hypoxia-induced pulmonary vascular remodeling and PAH in vivo and in vitro. In a mouse model of hypoxic PAH, SUMO1 expression was significantly increased, which was associated with activation of autophagy (increased LC3b and decreased p62), dedifferentiation of pulmonary arterial VSMCs (reduced α-SMA, SM22 and SM-MHC), and pulmonary vascular remodeling. Similar results were obtained in a MCT-induced PAH model. Overexpression of SUMO1 significantly increased VSMCs proliferation, migration, hypoxia-induced VSMCs dedifferentiation, and autophagy, but these effects were abolished by inhibition of autophagy by 3-MA in aortic VSMCs. Furthermore, SUMO1 knockdown reversed hypoxia-induced proliferation and migration of PASMCs. Mechanistically, SUMO1 promotes Vps34 SUMOylation and the assembly of the Beclin-1-Vps34-Atg14 complex, thereby inducing autophagy, whereas Vps34 mutation K840R reduces Vps34 SUMOylation and inhibits VSMCs dedifferentiation. Our data uncovers an important role of SUMO1 in VSMCs proliferation, migration, autophagy, and phenotypic switching (dedifferentiation) involved in pulmonary vascular remodeling and PAH. Targeting of the SUMO1-Vps34-autophagy signaling axis may be exploited to develop therapeutic strategies to treat PAH. Show less
UVRAG (UV radiation resistance associated) is an important regulator of mammalian macroautophagy/autophagy by interacting with BECN1, PIK3C3, and RUBCN. Phosphorylation of UVRAG by MTORC1 negatively r Show more
UVRAG (UV radiation resistance associated) is an important regulator of mammalian macroautophagy/autophagy by interacting with BECN1, PIK3C3, and RUBCN. Phosphorylation of UVRAG by MTORC1 negatively regulates autophagosome maturation under nutrient-enriched conditions. However, how UVRAG ubiquitination is regulated is still unknown. Here we report that UVRAG is ubiquitinated by SMURF1 at lysine residues 517 and 559, which decreases the association of UVRAG with RUBCN and promotes autophagosome maturation. However, the deubiquitinase ZRANB1 specifically cleaves SMURF1-induced K29 and K33-linked polyubiquitin chains from UVRAG, thereby increasing the binding of UVRAG to RUBCN and inhibiting autophagy flux. We also demonstrate that CSNK1A1-mediated UVRAG phosphorylation at Ser522 disrupts the binding of SMURF1 to UVRAG through PPxY motif and blocks UVRAG ubiquitination-mediated autophagosome maturation. Interestingly, ZRANB1 is phosphorylated at Thr35, and Ser209 residues by CSNK1A1, and this phosphorylation activates its deubiquitinating activity. Importantly, we provide Show less
Acute promyelocytic leukemia (APL) is characterized by t(15;17)(q22;q21), resulting in a PML-RARA fusion that is the master driver of APL. A few cases that cannot be identified with PML-RARA by using Show more
Acute promyelocytic leukemia (APL) is characterized by t(15;17)(q22;q21), resulting in a PML-RARA fusion that is the master driver of APL. A few cases that cannot be identified with PML-RARA by using conventional methods (karyotype analysis, FISH, and RT-PCR) involve abnormal promyelocytes that are fully in accordance with APL in morphology, cytochemistry, and immunophenotype. To explore the mechanisms involved in pathogenesis and recurrence of morphologically diagnosed APL, we performed comprehensive variant analysis by next-generation sequencing in 111 pediatric patients morphologically diagnosed as APL. Structural variant (SV) analysis in 120 DNA samples from both diagnosis and relapse stage identified 95 samples with RARA rearrangement (including 94 with PML-RARA and one with NPM-RARA) and two samples with KMT2A rearrangement. In the eligible 13 RNA samples without any RARA rearrangement at diagnosis, one case each with CPSF6-RARG, NPM1-CCDC28A, and TBC1D15-RAB21 and two cases with a TBL1XR1-RARB fusion were discovered. These uncovered fusion genes strongly suggested their contributions to leukemogenesis as driver alternations and APL phenotype may arise by abnormalities of other members of the nuclear receptor superfamily involved in retinoid signaling (RARB or RARG) or even by mechanisms distinct from the formation of aberrant retinoid receptors. Single-nucleotide variant (SNV) analysis in 77 children (80 samples) with RARA rearrangement showed recurrent alternations of primary APL in FLT3, WT1, USP9X, NRAS, and ARID1A, with a strong potential for involvement in pathogenesis, and WT1 as the only recurrently mutated gene in relapsed APL. WT1, NPM1, NRAS, FLT3, and NSD1 were identified as recurrently mutated in 17 primary samples without RARA rearrangement and WT1, NPM1, TP53, and RARA as recurrently mutated in 9 relapsed samples. The survival of APL with RARA rearrangement is much better than without RARA rearrangement. Thus, patients morphologically diagnosed as APL that cannot be identified as having a RARA rearrangement are more reasonably classified as a subclass of AML other than APL, and individualized treatment should be considered according to the genetic abnormalities. Show less
Lipopolysaccharide (LPS) induces macrophage/monocyte activation and pro-inflammatory cytokines production by activating Toll-like receptor 4 (TLR-4) signaling. Rab GTPase 21 (Rab21) is a member of the Show more
Lipopolysaccharide (LPS) induces macrophage/monocyte activation and pro-inflammatory cytokines production by activating Toll-like receptor 4 (TLR-4) signaling. Rab GTPase 21 (Rab21) is a member of the Rab GTPase subfamily. In the present study, we show that LPS induced TLR4 and Rab21 association and endosomal translocation in murine bone marrow-derived macrophages (BMDMs) and primary human peripheral blood mononuclear cells (PBMCs). In BMDMs, shRNA-mediated stable knockdown of Rab21 inhibited LPS-induced expression and production of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α). Conversely, forced overexpression of Rab21 by an adenovirus construct potentiated LPS-induced IL-1β, IL-6 and TNF-α production in BMDMs. Further studies show that LPS-induced TLR4 endosomal traffic and downstream c-Jun and NFκB (nuclear factor-kappa B) activation were significantly inhibited by Rab21 shRNA, but intensified with Rab21 overexpression in BMDMs. Finally, in the primary human PBMCs, siRNA-induced knockdown of Rab21 significantly inhibited LPS-induced IL-1β, IL-6 and TNF-α production. Taken together, we suggest that Rab21 regulates LPS-induced pro-inflammatory responses by promoting TLR4 endosomal traffic and downstream signaling activation. Show less
Neuromuscular junction is a synapse between motoneurons and skeletal muscles, where acetylcholine receptors (AChRs) are concentrated to control muscle contraction. Studies of this synapse have contrib Show more
Neuromuscular junction is a synapse between motoneurons and skeletal muscles, where acetylcholine receptors (AChRs) are concentrated to control muscle contraction. Studies of this synapse have contributed to our understanding of synapse assembly and pathological mechanisms of neuromuscular disorders. Nevertheless, underlying mechanisms of NMJ formation was not well understood. To this end, we took a novel approach - studying mutant genes implicated in congenital myasthenic syndrome (CMS). We showed that knock-in mice carrying N88K, a prevalent CMS mutation of Rapsyn (Rapsn), died soon after birth with profound NMJ deficits. Rapsn is an adapter protein that bridges AChRs to the cytoskeleton and possesses E3 ligase activity. In investigating how N88K impairs the NMJ, we uncovered a novel signaling pathway by which Agrin-LRP4-MuSK induces tyrosine phosphorylation of Rapsn, which is required for its self-association and E3 ligase activity. Our results also provide insight into pathological mechanisms of CMS. Show less
Early diagnosis is crucial to improve outcomes for pancreatic cancer patients (PC). The present study is designed to identify differently expressed peptides involved in PC as potential biomarkers. The Show more
Early diagnosis is crucial to improve outcomes for pancreatic cancer patients (PC). The present study is designed to identify differently expressed peptides involved in PC as potential biomarkers. The serum proteome of 22 PC patients, 12 pancreatitis patients (PP), and 45 healthy controls (HC) are analyzed using magnetic bead-based weak cation exchange (MB-WCX) and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Next, a supervised neural network (SNN) algorithm model is established by ClinProTools and the candidate biomarker identified using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Finally, the candidate biomarker is validated in tissue samples. The SNN algorithm model discriminates PC from HC with 92.97% sensitivity and 94.55% specificity. Seventy-six differentially expressed peptides are identified, seven of which are significantly different among PC, PP, and HC (p < 0.05). Only one peak (m/z: 1466.99) tends to be upregulated in samples from HC, PP, and PC, which is identified as region of RNA-binding motif protein 6 (RBM6). In subsequent tissue analysis, it is verified that RBM6 expression is significantly higher in PC tissues than paracancerous tissue. The results indicate that RBM6 might serve as a candidate diagnostic biomarker for PC. Methods used in this study could generate serum peptidome profiles of PC, PP, and HC, and present an approach to identify potential biomarkers for diagnosis of this malignancy. Show less
The aim of this study was to explore the role of microRNA-203 (miR-203) in Prostate Cancer (PCa), and to further verify its influence in PCa cell function. The expression level of miR-203 in 55 clinic Show more
The aim of this study was to explore the role of microRNA-203 (miR-203) in Prostate Cancer (PCa), and to further verify its influence in PCa cell function. The expression level of miR-203 in 55 clinical PCa cases and cell lines was detected by qRT-PCR. Then, the target gene of miR-203 in PCa cells was predicted and verified by online prediction software and Luciferase reporter gene assay, respectively. Furthermore, the role of miR-203 in PCa cell proliferation, colony formation, cell cycle and metastasis capacities was detected through a series of in vitro experiments. The expression of miR-203 in PCa tissues and cells was significantly reduced when compared with that of normal tissues and cells. In searching for potential downstream targets of miR-203, a regulator of G-protein signaling 17 (RGS17) entered our sight due to its active role in a variety of malignant tumors. More importantly, the negative regulation of RGS17 by miR-203 was verified by Luciferase reporter gene assay. Functional experiments demonstrated that low expression of RGS17 in PCa cells induced by up-regulation of miR-203 could significantly restrain the proliferation, invasion and migration capacities of PCa cells. MiR-203 served as a tumor suppressor gene in PCa. Through targeting RGS17, miR-203 significantly controlled the malignant behavior of PCa cells. Our findings revealed that miR-203/RGS17 axis might be a potential therapeutic target for the treatment of PCa. Show less
Antibody-drug conjugates (ADCs) selectively deliver chemotherapeutic agents to target cells and are important cancer therapeutics. However, the mechanisms by which ADCs are internalized and activated Show more
Antibody-drug conjugates (ADCs) selectively deliver chemotherapeutic agents to target cells and are important cancer therapeutics. However, the mechanisms by which ADCs are internalized and activated remain unclear. Using CRISPR-Cas9 screens, we uncover many known and novel endolysosomal regulators as modulators of ADC toxicity. We identify and characterize C18ORF8/RMC1 as a regulator of ADC toxicity through its role in endosomal maturation. Through comparative analysis of screens with ADCs bearing different linkers, we show that a subset of late endolysosomal regulators selectively influence toxicity of noncleavable linker ADCs. Surprisingly, we find cleavable valine-citrulline linkers can be processed rapidly after internalization without lysosomal delivery. Lastly, we show that sialic acid depletion enhances ADC lysosomal delivery and killing in diverse cancer cell types, including with FDA (US Food and Drug Administration)-approved trastuzumab emtansine (T-DM1) in Her2-positive breast cancer cells. Together, these results reveal new regulators of endolysosomal trafficking, provide important insights for ADC design and identify candidate combination therapy targets. Show less
Claudin6 (CLDN6), a member of the tight junction family, is a molecule involved in intercellular adhesion, acting as a physical barrier that prevents solutes and water from freely passing through the Show more
Claudin6 (CLDN6), a member of the tight junction family, is a molecule involved in intercellular adhesion, acting as a physical barrier that prevents solutes and water from freely passing through the extracellular space. CLDN6 has important biological functions, and its abnormal expression is associated with Hepatitis C infection. However, there is limited research regarding its role in gastric cancer. In this study, we found that the expression of CLDN6 mRNA and protein was upregulated in gastric cancer cell lines and tissues, which indicated poor prognosis. Both in vitro and in vivo experiments showed that abnormal CLDN6 expression was associated with enhanced proliferation and invasion abilities of gastric cancer. CLDN6 reduced the phosphorylation of LATS1/2 and YAP1 by interacting with LATS1/2 in the Hippo signaling pathway. Thus, CLDN6 affected the entry of YAP1 into the nucleus, causing changes in downstream target genes. Moreover, YAP1 interacted with snail1 to affect the process of EMT and enhanced the invasive ability of GC cells. Collectively, CLDN6 promoted the proliferation and invasive ability of gastric cancer by affecting YAP1 and YAP1-snail1 axis. Show less