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1.
Front Physiol ; 15: 1368542, 2024.
Article in English | MEDLINE | ID: mdl-38706946

ABSTRACT

Background: Many people infected with COVID-19 develop myocardial injury. Epicardial adipose tissue (EAT) is among the various risk factors contributing to coronary artery disease. However, its correlation with myocardial injury in patients diagnosed with COVID-19 remains uncertain. Methods: We examined myocardial biomarkers in population affected by COVID-19 during the period from December 2022 to January 2023. The patients without myocardial injury were referred to as group A (n = 152) and those with myocardial injury were referred to as group B (n = 212). Results: 1) The A group and the B group exhibitedstatistically significant differences in terms of age, TC, CRP, Cr, BUN, LDL-C, IL-6, BNP, LVEF and EAT (p < 0.05). 2) EAT volumehad a close relationship with IL-6, LDL-C, cTnI, and CRP (p < 0.05); the corresponding correlation coefficient values were 0.24, 0.21, 0.24, and 0.16. In contrast to those with lower EAT volume, more subjects with a higher volume of EAT had myocardial injury (p < 0.05). Regression analysis showed that EAT, LDL-C, Age and Cr were established as independent risk variables for myocardial injury in subjects affected by COVID-19. 3) In COVID-19 patients, the likelihood of myocardial injury rised notably as EAT levels increase (p < 0.001). Addition of EAT to the basic risk model for myocardial injury resulted in improved reclassification. (Net reclassification index: 58.17%, 95% CI: 38.35%, 77.99%, p < 0.001). Conclusion: Patients suffering from COVID-19 with higher volume EAT was prone to follow myocardial injury and EAT was an independent predictor of heart damage in these individuals.

2.
Gut ; 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38641363

ABSTRACT

INTRODUCTION: Epithelial-mesenchymal plasticity (EMP), the process through which epithelial cells acquire mesenchymal features, is needed for wound repair but also might contribute to cancer initiation. Earlier, in vitro studies showed that Barrett's cells exposed to acidic bile salt solutions (ABS) develop EMP. Now, we have (1) induced reflux oesophagitis in Barrett's oesophagus (BO) patients by stopping proton pump inhibitors (PPIs), (2) assessed their biopsies for EMP and (3) explored molecular pathways underlying reflux-induced EMP in BO cells and spheroids. METHODS: 15 BO patients had endoscopy with biopsies of Barrett's metaplasia while on PPIs, and 1 and 2 weeks after stopping PPIs; RNA-seq data were assessed for enrichments in hypoxia-inducible factors (HIFs), angiogenesis and EMP pathways. In BO biopsies, cell lines and spheroids, EMP features (motility) and markers (vascular endothelial growth factor (VEGF), ZEB1, miR-200a&b) were evaluated by morphology, migration assays, immunostaining and qPCR; HIF-1α was knocked down with siRNA or shRNA. RESULTS: At 1 and/or 2 weeks off PPIs, BO biopsies exhibited EMP features and markers, with significant enrichment for HIF-1α, angiogenesis and EMP pathways. In BO cells, ABS induced HIF-1α activation, which decreased miR-200a&b while increasing VEGF, ZEB1 and motility; HIF-1α knockdown blocked these effects. After ABS treatment, BO spheroids exhibited migratory protrusions showing nuclear HIF-1α, increased VEGF and decreased miR-200a&b. CONCLUSIONS: In BO patients, reflux oesophagitis induces EMP changes associated with increased HIF-1α signalling in Barrett's metaplasia. In Barrett's cells, ABS trigger EMP via HIF-1α signalling. Thus, HIF-1α appears to play a key role in mediating reflux-induced EMP that might contribute to cancer in BO. TRIAL REGISTRATION NUMBER: NCT02579460.

3.
Cancer Res ; 84(6): 827-840, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38241695

ABSTRACT

N6-methyladenosine (m6A) RNA modification is the most common and conserved epigenetic modification in mRNA and has been shown to play important roles in cancer biology. As the m6A reader YTHDF1 has been reported to promote progression of hepatocellular carcinoma (HCC), it represents a potential therapeutic target. In this study, we evaluated the clinical significance of YTHDF1 using human HCC samples and found that YTHDF1 was significantly upregulated in HCCs with high stemness scores and was positively associated with recurrence and poor prognosis. Analysis of HCC spheroids revealed that YTHDF1 was highly expressed in liver cancer stem cells (CSC). Stem cell-specific conditional Ythdf1 knockin (CKI) mice treated with diethylnitrosamine showed elevated tumor burden as compared with wild-type mice. YTHDF1 promoted CSCs renewal and resistance to the multiple tyrosine kinase inhibitors lenvatinib and sorafenib in patient-derived organoids and HCC cell lines, which could be abolished by catalytically inactive mutant YTHDF1. Multiomic analysis, including RNA immunoprecipitation sequencing, m6A methylated RNA immunoprecipitation sequencing, ribosome profiling, and RNA sequencing identified NOTCH1 as a direct downstream of YTHDF1. YTHDF1 bound to m6A modified NOTCH1 mRNA to enhance its stability and translation, which led to increased NOTCH1 target genes expression. NOTCH1 overexpression rescued HCC stemness in YTHDF1-deficient cells in vitro and in vivo. Lipid nanoparticles targeting YTHDF1 significantly enhanced the efficacy of lenvatinib and sorafenib in HCC in vivo. Taken together, YTHDF1 drives HCC stemness and drug resistance through an YTHDF1-m6A-NOTCH1 epitranscriptomic axis, and YTHDF1 is a potential therapeutic target for treating HCC. SIGNIFICANCE: Inhibition of YTHDF1 expression suppresses stemness of hepatocellular carcinoma cells and enhances sensitivity to targeted therapies, indicating that targeting YTHDF1 may be a promising therapeutic strategy for liver cancer.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Phenylurea Compounds , Quinolines , Humans , Animals , Mice , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Sorafenib , Drug Resistance, Neoplasm , Liver Neoplasms/drug therapy , Liver Neoplasms/genetics , Adenosine/pharmacology , RNA, Messenger , RNA , Receptor, Notch1/genetics , RNA-Binding Proteins/genetics
4.
J Assist Reprod Genet ; 40(9): 2185-2196, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37439868

ABSTRACT

PURPOSE: Preimplantation genetic testing (PGT) has become a reliable tool for preventing the germline transmission of mitochondrial DNA (mtDNA) variants. However, procedures are not standardized across mtDNA variants. In this study, we aim to estimate symptomatic thresholds, risk, and chance of success for PGT for mtDNA pathogenic variant carriers. METHODS: We performed a systematic analysis of heteroplasmy data including 455 individuals from 187 familial pedigrees with the common m.3243A>G, m.8344A>G, or m.8993T>G pathogenic variants. We applied binary logistic regression for estimating symptomatic thresholds of heteroplasmy, simplified Sewell-Wright formula and Kimura equations for predicting the risk of disease transmission, and binomial distribution for predicting minimum oocyte numbers. RESULTS: We estimated the symptomatic thresholds of m.8993T>G and m.8344A>G as 29.86% and 16.15%, respectively. We could not determine a threshold for m.3243A>G. We established models for mothers harboring common and rare mtDNA pathogenic variants to predict the risk of disease transmission and the number of oocytes required to produce an embryo with sufficiently low variant load. In addition, we provide a table allowing the prediction of transmission risk and the minimum required oocytes for PGT patients with different variant levels. CONCLUSION: We have established models that can determine the symptomatic thresholds of common mtDNA pathogenic variants. We also constructed universal models applicable to nearly all mtDNA pathogenic variants which can predict risk and minimum numbers for PGT patients. These models have advanced our understanding of mtDNA disease pathogenesis and will enable more effective prevention of disease transmission using PGT.


Subject(s)
DNA, Mitochondrial , Mitochondrial Diseases , Humans , DNA, Mitochondrial/genetics , DNA, Mitochondrial/analysis , Mitochondrial Diseases/diagnosis , Mitochondrial Diseases/genetics , Mitochondria/genetics , Germ Cells , Genetic Testing
5.
Cell Rep Med ; 4(8): 101128, 2023 08 15.
Article in English | MEDLINE | ID: mdl-37478857

ABSTRACT

Mechanical stress can modulate the fate of cells in both physiological and extreme conditions. Recurrence of tumors after thermal ablation, a radical therapy for many cancers, indicates that some tumor cells can endure temperatures far beyond physiological ones. This unusual heat resistance with unknown mechanisms remains a key obstacle to fully realizing the clinical potential of thermal ablation. By developing a 3D bioprinting-based thermal ablation system, we demonstrate that hepatocellular carcinoma (HCC) cells in this 3D model exhibit enhanced heat resistance as compared with cells on plates. Mechanistically, the activation of transcription factor SP1 under mechanical confinement enhances the transcription of Interleukin-4-Induced-1, which catalyzes tryptophan metabolites to activate the aryl hydrocarbon receptor (AHR), leading to heat resistance. Encouragingly, the AHR inhibitor prevents HCC recurrence after thermal ablation. These findings reveal a previously unknown role of mechanical confinement in heat resistance and provide a rationale for AHR inhibitors as neoadjuvant therapy.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/genetics , Liver Neoplasms/pathology , Receptors, Aryl Hydrocarbon/genetics , Receptors, Aryl Hydrocarbon/metabolism , Receptors, Aryl Hydrocarbon/therapeutic use , Hot Temperature , Neoadjuvant Therapy , L-Amino Acid Oxidase/therapeutic use
6.
Hepatology ; 77(4): 1122-1138, 2023 04 01.
Article in English | MEDLINE | ID: mdl-35598182

ABSTRACT

BACKGROUND AND AIMS: Radiofrequency ablation (RFA) is an important curative therapy in hepatocellular carcinoma (HCC), but recurrence rate remains as high as all the other HCC therapeutic modalities. Methyltransferase 1 (METTL1), an enzyme for m 7 G tRNA modification, was reported to promote HCC development. Here, we assessed the role of METTL1 in shaping the immunosuppressive tumor microenvironment after insufficient RFA (iRFA). APPROACH AND RESULTS: By immunohistochemistry and multiplex immunofluorescence (mIF) staining, we showed that METTL1 expression was enhanced in post-RFA recurrent HCC, accompanied by increased CD11b + CD15 + polymorphonuclear-myeloid-derived suppressor cells (PMN-MDSCs) and decreased CD8 + T cells. Mechanistically, heat-mediated METTL1 upregulation enhanced TGF-ß2 translation to form the immunosuppressive environment by induction of myeloid-derived suppressor cell. Liver-specific overexpression or knockdown of Mettl1 significantly affected the accumulation of PMN-MDSCs and subsequently affected CD8 + T cell infiltration. Complete RFA successfully eliminated the tumor, whereas iRFA-treated mice exhibited enhanced tumor growth and metastasis with increased PMN-MDSC accumulation and decreased CD8 + T cells compared to sham surgery. Interrupting METTL1-TGF-ß2-PMN-MDSC axis by anti-Ly6G antibody, or knockdown of hepatoma-intrinsic Mettl1 or Tgfb2 , or TGF-ß signaling blockade significantly mitigated tumor progression induced by iRFA and restored CD8 + T cell population. CONCLUSIONS: Our study sheds light on the pivotal role of METTL1 in modulating an immunosuppressive microenvironment and demonstrated that interrupting METTL1-TGF-ß2-PMN-MDSC axis could be a therapeutic strategy to restore antitumor immunity and prevent HCC recurrence after RFA treatment, meriting further clinical studies.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Myeloid-Derived Suppressor Cells , Mice , Animals , Carcinoma, Hepatocellular/metabolism , Myeloid-Derived Suppressor Cells/metabolism , Liver Neoplasms/pathology , Transforming Growth Factor beta2/metabolism , Tumor Microenvironment
7.
Mol Ther ; 31(6): 1596-1614, 2023 Jun 07.
Article in English | MEDLINE | ID: mdl-35965412

ABSTRACT

Radiofrequency heat ablation is an ideal radical treatment for hepatocellular carcinoma (HCC). However, insufficient radiofrequency ablation (IRFA) could lead to high recurrence of HCC. N7-methylguanosine (m7G) on tRNAs, an evolutionally conservative modification in mammals and yeast, modulates heat stress responses and tumor progression, while its function in HCC recurrence after IRFA remains unknown. Here, we found that IRFA significantly upregulates the level of m7G tRNA modification and its methyltransferase complex components METTL1/WDR4 in multiple systems including HCC patient-derived xenograft (PDX) mouse, patients' HCC tissues, sublethal-heat-treated models of HCC cell lines, and organoids. Functionally, gain-/loss-of-function assays showed that METTL1-mediated m7G tRNA modification promotes HCC metastasis under sublethal heat exposure both in vitro and in vivo. Mechanistically, we found that METTL1 and m7G tRNA modification enhance the translation of SLUG/SNAIL in a codon frequency-dependent manner under sublethal heat stress. Overexpression of SLUG/SNAIL rescued the malignant potency of METTL1 knockdown HCC cells after sublethal heat exposure. Our study uncovers the key functions of m7G tRNA modification in heat stress responses and HCC recurrence after IRFA, providing molecular basis for targeting METTL1-m7G-SLUG/SNAIL axis to prevent HCC metastasis after radiofrequency heat ablation treatment.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Radiofrequency Ablation , Humans , Mice , Animals , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/metabolism , RNA, Transfer/genetics , Mammals , GTP-Binding Proteins/metabolism
8.
Front Immunol ; 13: 1033000, 2022.
Article in English | MEDLINE | ID: mdl-36505437

ABSTRACT

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related death worldwide. Local ablation, such as radiofrequency ablation, microwave ablation, cryoablation and irreversible electroporation, etc., are well established in elimination and control of HCC. However, high recurrence rate after local ablation remains the biggest challenge for HCC management. Novel and effective therapeutic strategies to improve long-term survival are urgently needed. Accumulating studies have reported the role of ablation in modulating the tumor signaling pathway and the immune microenvironment to both eliminate residual/metastatic tumor and promote tumor progression. Ablation has been shown to elicit tumor-specific immune responses by inducing massive cell death and releasing tumor antigen. Immunotherapies that unleash the immune system have the potential to enhance the anti-tumor immunity induced by ablation. Multiple combinatory strategies have been explored in preclinical and clinical studies. In this review, we comprehensively summarize the latest progress on different mechanisms underlying the effects of ablation on tumor cells and tumor microenvironment. We further analyze the clinical trials testing the combination of ablation and immunotherapies, and discuss the possible role of immunomodulation to boost the anti-tumor effects of ablation and prevent HCC recurrence.


Subject(s)
Anti-Infective Agents , Carcinoma, Hepatocellular , Dermatologic Agents , Liver Neoplasms , Pulmonary Surfactants , Humans , Carcinoma, Hepatocellular/therapy , Liver Neoplasms/therapy , Penicillins , Immunotherapy , Immunoglobulins , Vitamins , Fibrinolytic Agents , Tumor Microenvironment
9.
Front Endocrinol (Lausanne) ; 13: 866116, 2022.
Article in English | MEDLINE | ID: mdl-36157445

ABSTRACT

The m6A methylation is the most numerous modification of mRNA in mammals, coordinated by RNA m6A methyltransferases, RNA m6A demethylases, and RNA m6A binding proteins. They change the RNA m6A methylation level in their specific manner. RNA m6A modification has a significant impact on lipid metabolic regulation. The "writer" METTL3/METTL14 and the "eraser" FTO can promote the accumulation of lipids in various cells by affecting the decomposition and synthesis of lipids. The "reader" YTHDF recognizes m6A methylation sites of RNA and regulates the target genes' translation. Due to this function that regulates lipid metabolism, RNA m6A methylation plays a pivotal role in metabolic diseases and makes it a great potential target for therapy.


Subject(s)
Adenosine , Lipid Metabolism , Adenosine/genetics , Adenosine/metabolism , Animals , Lipid Metabolism/genetics , Lipids , Mammals/genetics , Methylation , Methyltransferases/genetics , Methyltransferases/metabolism , RNA, Messenger/genetics
10.
Cancer Immunol Res ; 10(6): 728-744, 2022 06 03.
Article in English | MEDLINE | ID: mdl-35476700

ABSTRACT

A high rate of recurrence after curative therapy is a major challenge for the management of hepatocellular carcinoma (HCC). Currently, no effective adjuvant therapy is available to prevent HCC recurrence. We designed a personalized neoantigen-loaded dendritic cell vaccine and neoantigen-activated T-cell therapy, and used it as adjuvant therapy to treat 10 patients with HCC who had undergone curative resection or radiofrequency ablation in the first stage of a phase II trial (NCT03067493). The primary outcomes were safety and neoantigen-specific immune response. Disease-free survival (DFS) was also evaluated. The immunotherapy was successfully administered to all the patients without unexpected delay and demonstrated a reasonable safety profile with no grade ≥3 treatment-related side effects reported. Seventy percent of patients generated de novo circulating multiclonal neoantigen-specific T-cell responses. Induced neoantigen-specific immunity was maintained over time, and epitope spreading was observed. Patients who generated immune responses to treatment exhibited prolonged DFS compared with nonresponders (P = 0.012), with 71.4% experiencing no relapse for 2 years after curative treatment. High expression of an immune stimulatory signature, enhanced immune-cell infiltration (i.e., CD8+ T cells), and upregulated expression of T-cell inflammatory gene profiles were found in the primary tumors of the responders. In addition, neoantigen depletion (immunoediting) was present in the recurrent tumors compared with the primary tumors (7/9 vs. 1/17, P = 0.014), suggesting that immune evasion occurred under the pressure of immunotherapy. Our study indicates that neoantigen-based combination immunotherapy is feasible, safe, and has the potential to reduce HCC recurrence after curative treatment.


Subject(s)
Cancer Vaccines , Carcinoma, Hepatocellular , Liver Neoplasms , Antigens, Neoplasm , Carcinoma, Hepatocellular/metabolism , Dendritic Cells , Humans , Immunity , Immunotherapy , Liver Neoplasms/metabolism , Neoplasm Recurrence, Local , Vaccination
11.
Front Physiol ; 13: 856298, 2022.
Article in English | MEDLINE | ID: mdl-35309061

ABSTRACT

The morbidity and mortality of cardiovascular diseases (CVDs) have been increasing year by year all over the world and expanding greatly to the younger population, which becomes the leading causes of death globally that threatens human life safety. Prediction of the occurrence of diseases by using risk related adverse events is crucial for screening and early detection of CVDs. Thus, the discovery of new biomarkers that related to risks of CVDs are of urgent in the field. Retinol-binding protein 4 (RBP4) is a 21-kDa adipokine, mainly secreted by adipocytes. Besides its well-established function in the induction of insulin resistance, it has also been found in recent years to be closely associated with CVDs and other risk factors, such as hypertension, coronary heart disease, heart failure, obesity, and hyperlipidemia. In this review, we mainly focus on the progress of research that establishes the correlation between RBP4 and CVDs and the corresponding major risk factors in recent years.

12.
J Gastroenterol Hepatol ; 37(6): 1156-1168, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35233828

ABSTRACT

BACKGROUND AND AIM: Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive disease with the underlying mechanisms poorly understood. YTHDF1, an N6 -methyladenosine (m6 A) reader protein, has important physiological functions in regulation of tumor development. However, the effect of YTHDF1 on ICC progression remains unknown yet. METHODS: The expression level of YTHDF1 in human ICC tissue was examined in The Cancer Genome Atlas database and our cohort. The role of YTHDF1 was detected using two human ICC cell lines in vitro. An ICC tumorigenesis mouse model was established via hydrodynamic transfection of AKT/YAP plasmids. m6 A sequencing, RNA immunoprecipitation sequencing, and RNA sequencing were carried out to explore the mechanism of YTHDF1 modulating ICC progression. RESULTS: Here, we find that YTHDF1 is upregulated in ICC and associated with shorter survival of ICC patients. Depletion of YTHDF1 inhibits cell proliferation, migration, and invasion, while overexpression of wild-type YTHDF1, but not m6 A reader domain mutant YTHDF1, significantly enhances tumor cell growth and aggressive abilities in vitro. Moreover, overexpression of YTHDF1 promotes the AKT/YAP transfection-induced orthotopic ICC tumorigenesis and progression in vivo. Mechanistically, we identify that YTHDF1 regulates the translation of epidermal growth factor receptor (EGFR) mRNA via binding m6 A sites in the 3'-UTR of EGFR transcript, thus leading to aberrant activities of downstream signal pathways that impact tumor progression. CONCLUSIONS: Our data uncover the oncogenic function and m6 A reader-dependent mechanism of YTHDF1 in regulation of ICC progression. Restricting abnormal oncogenic mRNA translation by targeting YTHDF1 may be a novel and promising strategy for ICC treatment.


Subject(s)
Bile Duct Neoplasms , Cholangiocarcinoma , Animals , Bile Duct Neoplasms/pathology , Bile Ducts, Intrahepatic/pathology , Carcinogenesis , Cell Line, Tumor , Cholangiocarcinoma/pathology , ErbB Receptors/genetics , ErbB Receptors/metabolism , Humans , Mice , Protein Biosynthesis , Proto-Oncogene Proteins c-akt , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism
13.
Hepatology ; 74(3): 1339-1356, 2021 09.
Article in English | MEDLINE | ID: mdl-33638162

ABSTRACT

BACKGROUND AND AIMS: The dynamic N6-methyladenosine (m6 A) mRNA modification is essential for acute stress response and cancer progression. Sublethal heat stress from insufficient radiofrequency ablation (IRFA) has been confirmed to promote HCC progression; however, whether m6 A machinery is involved in IRFA-induced HCC recurrence remains open for study. APPROACH AND RESULTS: Using an IRFA HCC orthotopic mouse model, we detected a higher level of m6 A reader YTH N6-methyladenosine RNA binding protein 1-3 (YTHDF1) in the sublethal-heat-exposed transitional zone close to the ablation center than that in the farther area. In addition, we validated the increased m6 A modification and elevated YTHDF1 protein level in sublethal-heat-treated HCC cell lines, HCC patient-derived xenograft (PDX) mouse model, and patients' HCC tissues. Functionally, gain-of-function/loss-of-function assays showed that YTHDF1 promotes HCC cell viability and metastasis. Knockdown of YTHDF1 drastically restrains the tumor metastasis evoked by sublethal heat treatment in tail vein injection lung metastasis and orthotopic HCC mouse models. Mechanistically, we found that sublethal heat treatment increases epidermal factor growth receptor (EGFR) m6 A modification in the vicinity of the 5' untranslated region and promotes its binding with YTHDF1, which enhances the translation of EGFR mRNA. The sublethal-heat-induced up-regulation of EGFR level was further confirmed in the IRFA HCC PDX mouse model and patients' tissues. Combination of YTHDF1 silencing and EGFR inhibition suppressed the malignancies of HCC cells synergically. CONCLUSIONS: The m6 A-YTHDF1-EGFR axis promotes HCC progression after IRFA, supporting the rationale for targeting m6 A machinery combined with EGFR inhibitors to suppress HCC metastasis after RFA.


Subject(s)
Carcinoma, Hepatocellular/surgery , Liver Neoplasms/surgery , RNA Processing, Post-Transcriptional/radiation effects , RNA, Messenger/metabolism , RNA-Binding Proteins/radiation effects , Radiofrequency Ablation/adverse effects , Animals , Carcinoma, Hepatocellular/genetics , Cell Survival/genetics , Cell Survival/radiation effects , ErbB Receptors/genetics , ErbB Receptors/metabolism , ErbB Receptors/radiation effects , Gene Expression Regulation, Neoplastic , Heat-Shock Response/radiation effects , Humans , Liver Neoplasms/genetics , Methylation/radiation effects , Mice , Neoplasm Metastasis , Neoplasm Transplantation , RNA Processing, Post-Transcriptional/genetics , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Treatment Failure
14.
Methods Mol Biol ; 2171: 155-167, 2020.
Article in English | MEDLINE | ID: mdl-32705640

ABSTRACT

Single-cell RNA-sequencing (scRNA-seq) provides a unique opportunity to study heterogeneous cell populations within tissues, including the intestinal epithelium, to gain detailed molecular insights into their biology. Many new putative markers of intestinal stem cells and their progeny have been described using single-cell transcriptomics, which has contributed to the identification of novel subpopulations of mature cell types and insight into their developmental trajectories. This approach has revealed tremendous cellular heterogeneity within the intestinal epithelium that is concordant with its diverse and multifaceted functions. We discuss the function of these subpopulations during tissue homeostasis, as well as putative subpopulations with inducible regenerative potential following tissue injury.


Subject(s)
Intestinal Mucosa/cytology , Intestinal Mucosa/metabolism , Sequence Analysis, RNA/methods , Animals , Cell Differentiation/genetics , Cell Differentiation/physiology , Computational Biology/methods , Homeostasis/genetics , Homeostasis/physiology , Humans , Single-Cell Analysis , Transcriptome/genetics
16.
J Cancer ; 11(4): 819-825, 2020.
Article in English | MEDLINE | ID: mdl-31949485

ABSTRACT

We identified that Fibroblast Growth Factor 14 (FGF14) was preferentially methylated in colorectal cancer (CRC). In this study, we aimed to investigate the epigenetic regulation, biological function and molecular mechanism of FGF14 in CRC. The expression of FGF14 in CRC cell lines, normal human colon epithelial cell line, CRC tissues and paired adjacent normal tissues was detected by PCR and Western blot. The biological function of FGF14 in CRC was interrogated by cell viability assay, colony formation, flow cytometry, cell invasion and migration assay, as well as in vivo study. We found FGF14 was downregulated or silenced in all (10/10) CRC cell lines, while it was expressed in normal colonic tissues and normal human colon epithelial cell line. The expression of FGF14 was lower in primary CRCs as compared to their adjacent normal tissues. Significant higher methylation of FGF14 was observed in CRCs than that in normal tissues based on the data from TCGA database. The loss of FGF14 gene expression was restored by treatment with DNA methyltransferase inhibitor 5-Aza. Re-expression of FGF14 in CRC cell lines inhibited cell viability and colony formation, and induced cell apoptosis. FGF14 induced mitochondrial apoptosis and inhibited PI3K/AKT/mTOR pathway. In xenograft mouse model, overexpression of FGF14 significantly reduced tumor growth (P<0.001). In conclusion, FGF14 is a novel tumor suppressor, which suppresses cell proliferation and induces cell apoptosis via mediating PI3K/AKT/mTOR pathway.

17.
Cell Commun Signal ; 17(1): 152, 2019 11 21.
Article in English | MEDLINE | ID: mdl-31752873

ABSTRACT

BACKGROUND: Overexpression of erythropoietin (EPO) and EPO receptor (EPO-R) is associated with poor prognosis in non-small-cell lung carcinoma (NSCLC). Hypoxia, a potent EPO inducer, is a major stimulating factor in the growth of solid tumors. However, how EPO-R expression is regulated under hypoxia is largely unknown. METHODS: The role of EPO-R in NSCLC cell proliferation was assessed by RNA interference in vitro. Luciferase reporter assays were performed to map the promoter elements involved in the EPO-R mRNA transcription. Nuclear co-immunoprecipitation and chromatin immunoprecipitation were performed to assess the interaction among transcription factors HIF1α, SP1, and EGR1 in the regulation of EPO-R under hypoxia. The expression of key EPO-R transcription factors in clinical specimens were determined by immunohistochemistry. RESULTS: Hypoxia induced a dosage and time dependent EPO-R mRNA expression in NSCLC cells. Knockdown of EPO-R reduced NSCLC cell growth under hypoxia (P < 0.05). Mechanistically, a SP1-EGR1 overlapped DNA binding sequence was essential to the hypoxia induced EPO-R transcription. In the early phase of hypoxia, HIF1α interacted with EGR1 that negatively regulated EPO-R. With the exit of EGR1 in late phase, HIF1α positively regulated EPO-R expression through additive interaction with SP1. In clinical NSCLC specimen, SP1 was positively while EGR1 was negatively associated with active EPO-R expression (P < 0.05). CONCLUSIONS: HIF1α, SP1 and EGR1 mediated EPO-R expression played an essential role in hypoxia-induced NSCLC cell proliferation. Our study presents a novel mechanism of EPO-R regulation in the tumor cells, which may provide information support for NSCLC diagnosis and treatment.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Early Growth Response Protein 1/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Hypoxia/genetics , Lung Neoplasms/metabolism , Receptors, Erythropoietin/genetics , Sp1 Transcription Factor/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line , Cell Proliferation , Humans , Hypoxia/metabolism , Lung Neoplasms/pathology , Receptors, Erythropoietin/metabolism , Signal Transduction
18.
Cancer Med ; 8(4): 1530-1539, 2019 04.
Article in English | MEDLINE | ID: mdl-30864247

ABSTRACT

BACKGROUND: The role of transarterial chemoembolization (TACE) as the standard treatment for intermediate-stage hepatocellular carcinoma (HCC) is being challenged by increasing studies supporting liver resection (LR); but evidence of survival benefits of LR is lacking. We aimed to compare the overall survival (OS) of LR with that of TACE for the treatment of intermediate-stage HCC in cirrhotic patients. METHODS: A Markov model, comparing LR with TACE over 15 years, was developed based on the data from 31 literatures. Additionally, external validation of the model was performed using a data set (n = 1735; LR: 701; TACE: 1034) from a tertiary center with propensity score matching method. We conducted one-way and two-way sensitivity analyses, in addition to a Monte Carlo analysis with 10 000 patients allocated into each arm. RESULTS: The mean expected survival times and survival rates at 5 years were 77.8 months and 47.1% in LR group, and 48.6 months and 25.7% in TACE group, respectively. Sensitivity analyses found that initial LR was the most favorable treatment. The 95% CI for the difference in OS was 2.42-2.46 years between the two groups (P < 0.001). In the validation set, the 5-year survival rates after LR were significantly better than those after TACE before (40.2% vs. 25.9%, P < 0.001) and after matching (43.2% vs 30.9%, P < 0.001), which was comparable to the model results. CONCLUSIONS: For cirrhotic patients with resectable intermediate-stage HCC, LR may provide survival benefit over TACE, but large-scale studies are required to further stratify patients at this stage for different optimal treatments.


Subject(s)
Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic , Hepatectomy , Liver Neoplasms/pathology , Liver Neoplasms/therapy , Carcinoma, Hepatocellular/mortality , Chemoembolization, Therapeutic/adverse effects , Chemoembolization, Therapeutic/methods , Hepatectomy/adverse effects , Hepatectomy/methods , Humans , Liver Neoplasms/mortality , Markov Chains , Neoplasm Staging , Prognosis , Propensity Score , Survival Rate , Treatment Outcome
19.
J Pathol ; 246(4): 427-432, 2018 12.
Article in English | MEDLINE | ID: mdl-30146801

ABSTRACT

Inherited mitochondrial DNA (mtDNA) mutations cause mitochondrial disease, but mtDNA mutations also occur somatically and accumulate during ageing. Studies have shown that the mutation load of some inherited mtDNA mutations decreases over time in blood, suggesting selection against the mutation. However, it is unknown whether such selection occurs in other mitotic tissues, and where it occurs within the tissue. Gastrointestinal epithelium is a canonical mitotic tissue rapidly renewed by stem cells. Intestinal crypts (epithelium) undergo monoclonal conversion with a single stem cell taking over the niche and producing progeny. We show: (1) that there is a significantly lower mtDNA mutation load in the mitotic epithelium of the gastrointestinal tract when compared to the smooth muscle in the same tissue in patients with the pathogenic m.3243A>G and m.8344A>G mutations; (2) that there is considerable variation seen in individual crypts, suggesting changes in the stem cell population; (3) that this lower mutation load is reflected in the absence of a defect in oxidative phosphorylation in the epithelium. This suggests that there is selection against inherited mtDNA mutations in the gastrointestinal stem cells that is in marked contrast to the somatic mtDNA mutations that accumulate with age in epithelial stem cells leading to a biochemical defect. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Subject(s)
DNA, Mitochondrial/genetics , Epithelial Cells/chemistry , Gastric Mucosa/chemistry , Intestinal Mucosa/chemistry , Mitochondria/genetics , Mitochondrial Myopathies/genetics , Mutation , Stem Cells/chemistry , Adult , Case-Control Studies , Cellular Senescence/genetics , Epithelial Cells/pathology , Female , Gastric Mucosa/pathology , Genetic Predisposition to Disease , Heredity , Humans , Intestinal Mucosa/pathology , Middle Aged , Mitochondria/pathology , Mitochondrial Myopathies/pathology , Mitosis , Myocytes, Smooth Muscle/chemistry , Myocytes, Smooth Muscle/pathology , Oxidative Phosphorylation , Pedigree , Phenotype , RNA, Transfer, Leu/genetics , RNA, Transfer, Lys/genetics , Selection, Genetic , Stem Cells/pathology
20.
Genes (Basel) ; 9(4)2018 Mar 27.
Article in English | MEDLINE | ID: mdl-29584704

ABSTRACT

Mitochondrial DNA (mtDNA) mutations accumulate in somatic stem cells during ageing and cause mitochondrial dysfunction. In this review, we summarize the studies that link mtDNA mutations to stem cell ageing. We discuss the age-related behaviours of the somatic mtDNA mutations in stem cell populations and how they potentially contribute to stem cell ageing by altering mitochondrial properties in humans and in mtDNA-mutator mice. We also draw attention to the diverse fates of the mtDNA mutations with different origins during ageing, with potential selective pressures on the germline inherited but not the somatic mtDNA mutations.

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