MODIS Research Articles

Intestinal epithelial transcription factor HNF4A protects against microbiota dependent colitis and expansion of Akkermansia muciniphila

Development of the inflammatory bowel diseases (IBD) has been linked to altered homeostatic relationships between the intestine and the microbiota it harbors. However early preclinical stages of IBD remain poorly understood, especially with respect to host-microbiota interactions. The nuclear receptor transcription factor Hepatocyte nuclear factor 4 alpha (HNF4A) has important roles in intestinal epithelial cell (IEC) physiology, and our recent studies in zebrafish and mice revealed that HNF4A activity in IEC is suppressed by intestinal microbiota. Variants at HNF4A have been associated with human IBD, and IEC-specific knockout of Hnf4a in mice ( Hnf4a ΔIEC ) leads to spontaneous colonic inflammation by 6-12 months. We hypothesized that intestinal pathology in Hnf4a ΔIEC mice may begin earlier in life and that microbiota may contribute to that process. Longitudinal analysis revealed that Hnf4a ΔIEC mice reared in specific pathogen-free (SPF) conditions develop fecal lipocalin 2 (LCN2) flares and episodic loose stools beginning as early as 4-5 weeks of age. Lifetime cumulative LCN2 levels correlated with histopathological features of colitis at 12 months of age. Antibiotic and gnotobiotic tests showed that these phenotypes in Hnf4a ΔIEC mice were dependent on the presence of microbiota. Fecal 16S rRNA gene sequencing in an SPF cohort of Hnf4a ΔIEC mice and controls at 12 months of age disclosed that genotype was a significant contributor to alterations in microbiota composition. Longitudinal analysis in a subset of inflamed Hnf4a ΔIEC and wild-type mice revealed that microbial community differences emerged at early life stages when fecal LCN2 flares first arose. These microbiota differences included a salient increase in the relative abundance of Akkermansia muciniphila in a subset of Hnf4a ΔIEC mice. We isolated an A. muciniphila strain from an aged, inflamed Hnf4a ΔIEC mouse, and its genome sequence revealed it to be a member of a new Akkermansia phylogroup with genetic features distinct from the known phylogroups. We conclude that HNF4A functions in IEC throughout the lifespan to protect against episodic flares of inflammation induced by microbiota while also shaping microbiota assembly. These results establish Hnf4a ΔIEC mice as a useful model for investigating preclinical pathology and host-microbiota interactions that precede overt IBD onset. NIH P01-DK094779 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Genetic and clinical characteristics of Turkish children with Maturity Onset Diabetes of the Young Type 2 (MODY2): A single center experience

Objective: The aim of the study was to investigate the clinical and molecular genetic characteristics of children with maturity-onset diabetes of the youth-glucokinase (MODY-GCK, MODY type 2). Method: Medical files of 21 patients with suspected MODY-GCK were reviewed retrospectively. The file records of the clinical findings, laboratory results and the suspected clinical diagnoses of MODY were based on (1) asymptomatic fasting hyperglycemia (glucose ≥100mg/dl, HbA1c < 7.5% (at least twice measurement) 2) parents with a history of diabetes without complications or mild fasting hyperglycemia (100-144mg/dL). Results: The mean age at diagnosis was 11.5±4.3 years (min-max, 1.9-17.2). The mean (SD) fasting blood glucose level was 119.1 (9.8) mg/dL. The mean (SD) fasting C-peptide level was 1.3 (0.7) ng/mL, the mean (SD) insulin level was 5.9 (2.3) IU/ml, and the mean (SD) HbA1c level at diagnosis was 6.2 (0.5) %. Among 12 variants detected in the GCK gene, 8 were missense mutation, 2 were non-sense mutation, 1 of them was splice site and 1 of them was frameshift mutation. Eight of them (p. Val227Met, p. Ser282Ala, p.Val183Met, p.Met239Thr, p.Arg304Gln, p.Thr229Met, p.Gly163Asp, p.Cys130Ter) have been previously reported in the literature and 4 variants (c.582+4delA, p.Glu436Ter, p.His106ThrfsTer11, p.Asp133Gly) were novel. Conclusion: We found similar phenotype characteristic of children with GCK-MODY among the children with different variants. The most common mutation type was missense and followed by nonsense, splice site and frameshift mutations. Detection of the molecular defect in patients with MODY is vital for the implementation of appropriate treatment approaches.

Abstract 5580: Circulating tumor DNA (ctDNA) identifies genomic alterations associated with resistance to Nivolumab in combination with other agents in metastatic castration-resistant prostate cancer from the CheckMate 9KD trial

Abstract Introduction: Metastatic castration-resistant prostate cancer (mCRPC) is characterized by an immunosuppressive tumor microenvironment resulting in resistance to single agent immunotherapy, and several combination strategies are being clinically evaluated to address this resistance. CheckMate 9KD (NCT03338790) was a nonrandomized, open-label, multicohort, phase 2 trial of nivolumab combined with rucaparib, docetaxel, or enzalutamide for mCRPC, which showed encouraging clinical activity for the nivolumab plus docetaxel combination. To identify genetic factors potentially associated with response or resistance in this trial, we conducted a retrospective analysis of the tumor genomic alteration landscape utilizing circulating tumor DNA (ctDNA) from plasma samples. Methods: We performed integrated analyses of sequence and structural alterations identified through comprehensive genomic profiling of cell-free DNA (cfDNA) obtained from plasma at baseline using the GuardantOMNI™ assay (500 genes). The analysis was performed on 253 unique samples across all cohorts for which both clinical and OMNI datasets were available. Variant prevalence in ctDNA was compared to that of matched tumor tissue using the FoundationONE® assay (395 genes). Hazard ratios with corresponding two-sided 95% CI were estimated via unstratified multivariable Cox modeling adjusted by subject age and homologous recombination repair deficiency (HRD) status. Odds ratios with corresponding two-sided 95% CI were estimated via unstratified logistic regression modeling adjusted by subject age and HRD status. Results: Most patients (239/253; 94.5%) were ctDNA(+), with a substantially higher prevalence of most gene variants detected in cfDNA compared to patient-matched tumor tissue. Mutations in the AR, TERT, DNMT3A, HNF1A, and TP53 genes had the highest frequency. Amplifications in a number of genes detected in ctDNA including the androgen receptor (AR), PI3K/Akt pathway regulators (PIK3CA, PIK3CB, PREX2), and epigenetic regulators (DNMT3A, EZH2, KDM6A), were positively associated with poorer clinical outcomes (rPFS and/or OS) in the nivolumab + docetaxel arm. Conclusions: This investigation highlights the utility of liquid biopsy for evaluating tumor genomic alterations in late-stage mCRPC trials and provides translational insights into potential resistance mechanisms to inform patient selection and combination strategies for future clinical development. Acknowledgements: We acknowledge the patients and families, clinical study teams, and investigators who made the CheckMate 9KD study possible, and acknowledge Guardant Health and Foundation Medicine for the collaborative development and validation of the GuardantOMNI™ and FoundationOne®CDx assays, respectively. Citation Format: Yu Wang, Jun Li, Jonathan Baden, Saurabh Gupta, Justin M. David. Circulating tumor DNA (ctDNA) identifies genomic alterations associated with resistance to Nivolumab in combination with other agents in metastatic castration-resistant prostate cancer from the CheckMate 9KD trial. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5580.

The Use of Cell-penetrating Peptide for Delivery of Recombinant Transcription Factor DNA into Primary Human Fibroblast

Background: Reprogrammed cell therapy has not been applied for clinical purposes due to the malignancy issue. The aim of this study was to design the recombinant vector of the transcription factors and analyze the effectiveness of cell-penetrating peptide delivering system for human primary fibroblast transfection to avoid the malignancy issue.Materials and methods: The constructions of CCAT/enhancer binding protein alpha (CEBPA), hepatocyte nuclear factor 4 alpha (HNF4A), nuclear receptor subfamily 1 group I member 2 (NR1I2) were confirmed with DNA digestion and sequencing. Breast reduction (BRED) and palate (PAL) tissue were used as human primary fibroblast sources. The transcription factors were delivered into BRED and PAL with recombination of avian leukosis sarcoma virus (ALSV), human immunodeficiency virus (HIV) matrix, and regulator of expression of virion proteins (Rev) (ALMR), tagged with enhanced green fluorescence protein (eGFP). Post-transfection cells were then cultivated with optimized medium. Gene expression was measured with quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR).Results: Gene expression levels of CEBPA, HNF4A, NR1I2, glutamate-ammonia ligase (GLUL), albumin (ALB), and cytochrome P450 (CYP) were increased. Transfection with ALMR, which were more efficient in BRED than PAL fibroblasts may have the advantage in autologous cell therapy for elderly patients.Conclusion: Transfection of transcription factors to human primary fibroblast may be performed by using constructions of plasmid as designed in this study.Keywords: recombinant plasmid, hepatocyte-like cells, primary fibroblasts, recombinant peptide, cell reprogramming, autologous cells therapy

Ypel5 regulates liver development and function in zebrafish.

YPEL5 is a member of the Yippee-like (YPEL) gene family that is evolutionarily conserved in eukaryotic species. To date, the physiological function of YPEL5 has not been assessed due to a paucity of genetic animal models. Here, using CRISPR/Cas9-mediated genome editing, we generated a stable ypel5-/- mutant zebrafish line. Disruption of ypel5 expression leads to liver enlargement associated with hepatic cell proliferation. Meanwhile, hepatic metabolism and function are dysregulated in ypel5-/- mutant zebrafish, as revealed by metabolomic and transcriptomic analyses. Mechanistically, Hnf4a is identified as a crucial downstream mediator that is positively regulated by Ypel5. Zebrafish hnf4a overexpression could largely rescue ypel5 deficiency-induced hepatic defects. Furthermore, PPARα signaling mediates the regulation of Hnf4a by Ypel5 through directly binding to the transcriptional enhancer of the Hnf4a gene. Herein, this work demonstrates an essential role of Ypel5 in hepatocyte proliferation and function and provides the first in vivo evidence for a physiological role of the ypel5 gene in vertebrates.

Hepatocyte Nuclear Factor-1α Increases Fibrinogen Gene Expression in Liver and Plasma Fibrinogen Concentration in Rats with Experimental Chronic Renal Failure

Chronic kidney disease (CKD) is associated with elevated plasma fibrinogen concentration. However, the underlying molecular mechanism for elevated plasma fibrinogen concentration in CKD patients has not yet been clarified. We recently found that HNF1α was significantly upregulated in the liver of chronic renal failure (CRF) rats, an experimental model of CKD in patients. Given that the promoter region of the fibrinogen gene possesses potential binding sites for HNF1α, we hypothesized that the upregulation of HNF1α can increase fibrinogen gene expression and consequently plasma fibrinogen concentration in the experimental model of CKD. Here, we found the coordinated upregulation of Aα-chain fibrinogen and Hnfα gene expression in the liver and elevated plasma fibrinogen concentrations in CRF rats, compared with pair-fed and control animals. Liver Aα-chain fibrinogen and HNF1α mRNAs levels correlated positively with (a) liver and plasma fibrinogen levels and (b) liver HNF1α protein levels. The positive correlation between (a) liver Aα-chain fibrinogen mRNA level, (b) liver Aα-chain fibrinogen level, and (c) serum markers of renal function suggest that fibrinogen gene transcription is closely related to the progression of kidney disease. Knockdown of Hnfα in the HepG2 cell line by small interfering RNA (siRNA) led to a decrease in fibrinogen mRNA levels. Clofibrate, an anti-lipidemic drug that reduces plasma fibrinogen concentration in humans, decreased both HNF1α and Aα-chain fibrinogen mRNAs levels in (a) the liver of CRF rats and (b) HepG2 cells. The obtained results suggest that (a) an elevated level of liver HNF1α can play an important role in the upregulation of fibrinogen gene expression in the liver of CRF rats, leading to an elevated concentration of plasma fibrinogen, a protein related to the risk of cardiovascular disease in CKD patients, and (b) fibrates can decrease plasma fibrinogen concentration through inhibition of HNF1α gene expression.

TUBB2B facilitates progression of hepatocellular carcinoma by regulating cholesterol metabolism through targeting HNF4A/CYP27A1

Cholesterol metabolism plays a critical role in the progression of hepatocellular carcinoma (HCC), but it is not clear how cholesterol metabolism is regulated. The tubulin beta class I genes (TUBBs) are associated with the prognosis of many different cancers. To confirm the function of TUBBs in HCC, the Kaplan–Meier method and Cox analyses were performed using TCGA and GSE14520 datasets. A higher expression of TUBB2B is an independent prognostic factor for shorter over survival in HCC patients. Deletion of TUBB2B in hepatocytes inhibits proliferation and promotes tumor cell apoptosis, while over-expression of TUBB2B has the opposite function. This result was confirmed in a mouse xenograft tumor model. Mechanistically, TUBB2B induces the expression of CYP27A1, an enzyme responsible for the conversion of cholesterol to 27-hydroxycholesterol, which leads to the up-regulation of cholesterol and the progression of HCC. In addition, TUBB2B regulates CYP27A1 via human hepatocyte nuclear factor 4alpha (HNF4A). These findings indicated that TUBB2B functions as an oncogene in HCC, and plays a role in promoting cell proliferation and anti-apoptosis through targeting HNF4A/CYP27A1/cholesterol.

Proof-of-concept Application of Continuous Glucose Monitoring Data Analytics to Identify Diabetes Glucotypes.

In this proof-of-concept study, we evaluated if monogenic diabetes resulting from mutations of the HNF-1α gene (HNF1A-MODY) has a distinctive continuous glucose monitoring (CGM) glucotype, in comparison to type 1 diabetes (T1D). Using CGM data from 5 subjects with HNF1A-MODY and 115 subjects with T1D, we calculated multiple glucose metrics, including measures of within- and between-day variability (such as coefficient variation for each hour [CVb_1h]). The MODY and T1D cohorts had minimum CVb_1h of 11.3 ± 4.4 and 18.0 ± 4.9, respectively (P = .02) and maximum CVb_1h of 33.9 ± 5.0 and 50.3 ± 10, respectively (P < .001). All subjects with HNF1A-MODY had a minimum %CVb_1h ≤ 17.3% and maximum %CVb_1h ≤ 37.1%. In contrast, only 12 of 115 subjects with T1D had both a minimum and maximum %CVb_1h below these thresholds (P < .001). HNF1A- MODY is characterized by a low hourly, between-day glucose variability. CGM-derived glucose metrics may have potential applicability for screening for atypical diabetes phenotypes in the T1D population.

Genetic Variants of HNF4A, WFS1, DUSP9, FTO, and ZFAND6 Genes Are Associated with Prediabetes Susceptibility and Inflammatory Markers in the Saudi Arabian Population

Prediabetes is a reversible, intermediate stage of type 2 diabetes mellitus (T2DM). Lifestyle changes that include healthy diet and exercise can substantially reduce progression to T2DM. The present study explored the association of 37 T2DM- and obesity-linked single nucleotide polymorphisms (SNPs) with prediabetes risk in a homogenous Saudi Arabian population. A total of 1129 Saudi adults [332 with prediabetes (29%) and 797 normoglycemic controls] were randomly selected and genotyped using the KASPar SNP genotyping method. Anthropometric and various serological parameters were measured following standard procedures. Heterozygous GA of HNF4A-rs4812829 (0.64; 95% CI 0.47-0.86; p < 0.01), heterozygous TC of WFS1-rs1801214 (0.60; 95% confidence interval (CI) 0.44-0.80; p < 0.01), heterozygous GA of DUSP9-rs5945326 (0.60; 95% CI 0.39-0.92; p = 0.01), heterozygous GA of ZFAND6-rs11634397 (0.75; 95% CI 0.56-1.01; p = 0.05), and homozygous AA of FTO-rs11642841 (1.50; 95% CI 0.8-1.45; p = 0.03) were significantly associated with prediabetes, independent of age and body mass index (BMI). Additionally, C-reactive protein (CRP) levels in rs11634397 (AA) with a median of 5389.0 (2767.4-7412.8) were significantly higher than in the heterozygous GA genotype with a median of 1736.3 (1024.4-4452.0) (p < 0.01). In conclusion, only five of the 37 genetic variants previously linked to T2DM and obesity in the Saudi Arabian population [HNF4A-rs4812829, WFS1-rs1801214, DUSP9-rs5945326, ZFAND6-rs11634397, FTO-rs11642841] were associated with prediabetes susceptibility. Prospective studies are needed to confirm the potential clinical value of the studied genetic variants of interest.

Glucokinase Inactivation Ameliorates Lipid Accumulation and Exerts Favorable Effects on Lipid Metabolism in Hepatocytes

Glucokinase-maturity onset diabetes of the young (GCK-MODY) is a kind of rare diabetes with low incidence of vascular complications caused by GCK gene inactivation. This study aimed to investigate the effects of GCK inactivation on hepatic lipid metabolism and inflammation, providing evidence for the cardioprotective mechanism in GCK-MODY. We enrolled GCK-MODY, type 1 and 2 diabetes patients to analyze their lipid profiles, and found that GCK-MODY individuals exhibited cardioprotective lipid profile with lower triacylglycerol and elevated HDL-c. To further explore the effects of GCK inactivation on hepatic lipid metabolism, GCK knockdown HepG2 and AML-12 cell models were established, and in vitro studies showed that GCK knockdown alleviated lipid accumulation and decreased the expression of inflammation-related genes under fatty acid treatment. Lipidomic analysis indicated that the partial inhibition of GCK altered the levels of several lipid species with decreased saturated fatty acids and glycerolipids including triacylglycerol and diacylglycerol, and increased phosphatidylcholine in HepG2 cells. The hepatic lipid metabolism altered by GCK inactivation was regulated by the enzymes involved in de novo lipogenesis, lipolysis, fatty acid β-oxidation and the Kennedy pathway. Finally, we concluded that partial inactivation of GCK exhibited beneficial effects in hepatic lipid metabolism and inflammation, which potentially underlies the protective lipid profile and low cardiovascular risks in GCK-MODY patients.

A Variant In The HNF4A Gene Causing MODY-1 In A Teenage Girl: Optimal Glycaemic Control After Transition To Sulfonylurea

Maturity-Onset Diabetes of the Young (MODY) is a group of monogenic autosomal dominant forms of diabetes, characterized by early-onset of hyperglycemia, and typically the presence of a family history of diabetes in more than one generation. These features are also present in Type 1 and Type 2 Diabetes Mellitus, which frequently leads to misdiagnosis. There are various MODY subtypes, caused by mutations in 14 known genes, which share a primary defect in insulin secretion.

Phosphomannomutase 2 (PMM2) variants leading to hyperinsulinism-polycystic kidney disease are associated with early-onset inflammatory bowel disease and gastric antral foveolar hyperplasia

Phosphomannomutase 2 (PMM2) deficiency causes Congenital Disorder of Glycosylation (PMM2-CDG), but does not have a recognised association with Inflammatory Bowel Disease (IBD). A distinct clinical syndrome of hyperinsulinism and autosomal recessive polycystic kidney disease (HIPKD) arises in the context of a specific variant in the PMM2 promotor, either in homozygosity, or compound heterozygous with a deleterious PMM2 variant. Here, we describe the development of IBD in three patients with PMM2-HIPKD, with onset of IBD at 0, 6, and 10 years of age. In each case, intestinal inflammation coincided with the unusual finding of gastric antral foveolar hyperplasia. IBD disease was of variable severity at onset but well controlled with conventional and first-line biologic treatment approaches. The organ-level pattern of disease manifestations in PMM2-HIPKD-IBD may reflect a loss of cis-acting regulatory control by hepatocyte nuclear factor 4 alpha (HNF4A). Analysis of published transcriptomic data suggests that IBD most likely arises due to an impact on epithelial cellular function. We identify a specific pattern of variation in PMM2 as a novel association of early-onset IBD with distinctive gastric pathology.

The Mutation Spectrum of Rare Variants in the Gene of Adenosine Triphosphate (ATP)-Binding Cassette Subfamily C Member 8 in Patients with a MODY Phenotype in Western Siberia

During differential diagnosis of diabetes mellitus, the greatest difficulties are encountered with young patients because various types of diabetes can manifest themselves in this age group (type 1, type 2, and monogenic types of diabetes mellitus, including maturity-onset diabetes of the young (MODY)). The MODY phenotype is associated with gene mutations leading to pancreatic-β-cell dysfunction. Using next-generation sequencing technology, targeted sequencing of coding regions and adjacent splicing sites of MODY-associated genes (HNF4A, GCK, HNF1A, PDX1, HNF1B, NEUROD1, KLF11, CEL, PAX4, INS, BLK, KCNJ11, ABCC8, and APPL1) was carried out in 285 probands. Previously reported missense variants c.970G>A (p.Val324Met) and c.1562G>A (p.Arg521Gln) in the ABCC8 gene were found once each in different probands. Variant c.1562G>A (p.Arg521Gln) in ABCC8 was detected in a compound heterozygous state with a pathogenic variant of the HNF1A gene in a diabetes patient and his mother. Novel frameshift mutation c.4609_4610insC (p.His1537ProfsTer22) in this gene was found in one patient. All these variants were detected in available family members of the patients and cosegregated with diabetes mellitus. Thus, next-generation sequencing of MODY-associated genes is an important step in the diagnosis of rare MODY subtypes.

Concurrent inactivating mutations and expression losses of RGS2, HNF1A, and CAPN12 candidate tumor suppressor genes in colon cancers.

Microsatellite instability-high (MSI-H) colorectal cancer (CRC) is different from microsatellite stable (MSS) CRC concerning biological, and clinical features. In MSI-H CRCs, defects of mismatch repair genes produce increased mutation accumulation in repetitive DNA sequences. To see whether candidate tumor suppressor genes (TSGs) are altered in MSI-H CRC, we studied frameshift mutation and protein expression of candidate TSGs of RGS2, HNF1A, HNF1B, CAPN12, RCBTB2, ATE1, PKNOX1, and USP19. We found frameshift mutations of RGS2 in 5 (5%), HNF1A in 6 (6%), HNF1B in 2 (2%), CAPN12 in 3 (3%), RCBTB2 in 4 (4%), ATE1 in 2 (2%), PKNOX1 in 2 (2%), and USP19 in 2 (2%) MSI-H CRCs. However, we found no such mutations in MSS CRCs. RCBTB2, CAPN12, HNF1A, and HNF1B frameshift mutations revealed the regional difference in the same tumors. In addition, we identified loss of RGS2, HNF1A, and CAPN12 protein expression irrespective of MSI phenotype in 13-29% of CRCs. The results indicate that many TSGs harbor concurrent inactivating mutations and protein loss in MSI-H CRCs with intratumoral mutational heterogeneity, and that MSS CRCs are altered by protein losses. These alterations could contribute to CRC development and underlying mechanisms and consequences of the TSG alterations remain to be clarified.

Detection of lineage-reprogramming efficiency of tumor cells in a 3D-printed liver-on-a-chip model.

Background: The liver metastasis accompanied with the loss of liver function is one of the most common complications in patients with triple-negative breast cancers (TNBC). Lineage reprogramming, as a technique direct inducing the functional cell types from one lineage to another lineage without passing through an intermediate pluripotent stage, is promising in changing cell fates and overcoming the limitations of primary cells. However, most reprogramming techniques are derived from human fibroblasts, and whether cancer cells can be reversed into hepatocytes remains elusive. Methods: Herein, we simplify preparation of reprogramming reagents by expressing six transcriptional factors (HNF4A, FOXA2, FOXA3, ATF5, PROX1, and HNF1) from two lentiviral vectors, each expressing three factors. Then the virus was transduced into MDA-MB-231 cells to generated human induced hepatocyte-like cells (hiHeps) and single-cell sequencing was used to analyze the fate for the cells after reprogramming. Furthermore, we constructed a Liver-on-a-chip (LOC) model by bioprinting the Gelatin Methacryloyl hydrogel loaded with hepatocyte extracellular vesicles (GelMA-EV) bioink onto the microfluidic chip to assess the metastasis behavior of the reprogrammed TNBC cells under the 3D liver microenvironment in vitro. Results: The combination of the genes HNF4A, FOXA2, FOXA3, ATF5, PROX1 and HNF1A could reprogram MDA-MB-231 tumor cells into human-induced hepatocytes (hiHeps), limiting metastasis of these cells. Single-cell sequencing analysis showed that the oncogenes were significantly inhibited while the liver-specific genes were activated after lineage reprogramming. Finally, the constructed LOC model showed that the hepatic phenotypes of the reprogrammed cells could be observed, and the metastasis of embedded cancer cells could be inhibited under the liver microenvironment. Conclusion: Our findings demonstrate that reprogramming could be a promising method to produce hepatocytes and treat TNBC liver metastasis. And the LOC model could intimate the 3D liver microenvironment and assess the behavior of the reprogrammed TNBC cells.

Neonatal and early-onset diabetes in Ukraine: Atypical features and mortality.

The aim of this study is to elucidate the aetiology and clinical features of neonatal and early-onset diabetes in a large database for pediatric diabetes patients in Ukraine. We established a Pediatric Diabetes Register to identify patients diagnosed with diabetes before 9months of age. Genetic testing was undertaken for 66 patients from 65 unrelated families with diabetes diagnosed within the first 6months of life (neonatal diabetes, n=36) or between 6 and 9months (early-onset diabetes, n=30). We determined the genetic aetiology in 86.1% of patients (31/36) diagnosed before 6months and in 20% (6/30) diagnosed between 6 and 9months. Fourteen individuals (37.8% of those with a genetic cause identified) had activating heterozygous variants in ABCC8 or KCNJ11. An additional 10 individuals had pathogenic variants in the INS or GCK genes, while 4 had 6q24 transient neonatal diabetes. Rare genetic subtypes (including pathogenic variants in EIF2AK3, GLIS3, INSR, PDX1, LRBA, RFX6 and FOXP3) were identified in nine probands (24.3% of solved cases), 6 of whom died. In total, eight individuals died between infancy and childhood, all of them were diagnosed before 6months and had received a genetic diagnosis. In the last decade, the increased availability of comprehensive genetic testing has resulted in increased recognition of the contribution of rare genetic subtypes within pediatric diabetes cohorts. In our study, we identified a high mortality rate among these patients.

YTHDF3 mediates HNF1α regulation of cervical cancer radio-resistance by promoting RAD51D translation in an m6A-dependent manner.

Radiotherapy, as an important primary treatment, has effectively improved the survival of patients with cervical cancer (CC). Some patients, however, do not benefit optimally from radiotherapy because of radio-resistance. Therefore, identifying radio-resistance biomarkers and unravelling the underlying mechanisms is of critical importance for these patients. In the present study, we found significant upregulation of hepatocyte nuclear factor 1-alpha (HNF1α) expression in radio-resistant cervical cancer tissues and cell lines. Depletion of HNF1α reduced and overexpression of HNF1α promoted the resistance of CC cells to irradiation invitro and invivo. HNF1α positively regulated DNA repair protein RAD51 homologue 4 (RAD51D) at the protein level but not at the mRNA level. Mechanistically, upregulation of HNF1α enhanced YTH domain-containing family protein 3 (YTHDF3) transcription, which in turn promoted RAD51D mRNA N6 -methyladenosine (m6A) modification. YTHDF3 mediates HNF1α regulation of cervical cancer radio-resistance by promoting RAD51D translation in an m6A-dependent manner. The HFN1α/YTHDF3/RAD51D regulatory axis was found to play a critical role in conferring radio-resistance of CC cells. In conclusion, dysregulation of the HFN1α/YTHDF3/RAD51D axis may promote the radio-resistance of CC cells. Blocking this pathway may provide therapeutic benefits against CC radio-resistance.

Targeted gene panel analysis of Japanese patients with maturity-onset diabetes of the young-like diabetes mellitus: Roles of inactivating variants in the ABCC8 and insulin resistance genes.

To investigate the genetic background of Japanese patients with suspected maturity-onset diabetes of the young (MODY). On 340 proband patients referred from across Japan, genomic variants were analyzed using a targeted multigene panel analysis combined with the multiplex ligation probe amplification (MLPA) analysis, mitochondrial m.3243A > G analysis and methylation-specific polymerase chain reaction of the imprinted 6q24 locus. Pathogenic/likely pathogenic variants were listed according to the 2015 American College of Medical Genetics and Genomics and the Association for Molecular Pathology criteria. Additionally, variants with a population frequency <0.001 and Combined Annotation Dependent Depletion score >20 (CS >20) were listed as rare variants of uncertain significance-CS >20. A total of 157 pathogenic/likely pathogenic variants and 44 rare variants of uncertain significance-CS >20 were identified. In the pathogenic/likely pathogenic variants, alterations in the GCK gene were the most common (82, 52.2%) followed by HNF1A (29,18.5%), HNF4A (13, 8.3%) and HNF1B (13, 8.3%). One patient was a 29.5% mosaic with a truncating INSR variant. In the rare variants of uncertain significance-CS >20, 20 (45.5%) were in the genes coding for the adenosine triphosphate-sensitive potassium channel, KCNJ11 or ABCC8, and four were in the genes of the insulin-signaling pathway, INSR and PIK3R1. Four variants in ABCC8 were previously reported in patients with congenital hyperinsulinism, suggesting the inactivating nature of these variants, and at least two of our patients had a history of congenital hyperinsulinism evolving into diabetes. In two patients with INSR or PIK3R1 variants, insulin resistance was evident at diagnosis. Causative genomic variants could be identified in at least 46.2% of clinically suspected MODY patients. ABCC8-MODY with inactivating variants could represent a distinct category of MODY. Genes of insulin resistance should be included in the sequencing panel for MODY.

Polystyrene nanoplastics affect transcriptomic and epigenomic signatures of human fibroblasts and derived induced pluripotent stem cells: Implications for human health

Plastic pollution is increasing at an alarming rate yet the impact of this pollution on human health is poorly understood. Because human induced pluripotent stem cells (hiPSC) are frequently derived from dermal fibroblasts, these cells offer a powerful platform for the identification of molecular biomarkers of environmental pollution in human cells. Here, we describe a novel proof-of-concept for deriving hiPSC from human dermal fibroblasts deliberately exposed to polystyrene (PS) nanoplastic particles; unexposed hiPSC served as controls. In parallel, unexposed hiPSC were exposed to low and high concentrations of PS nanoparticles. Transcriptomic and epigenomic signatures of all fibroblasts and hiPSCs were defined using RNA-seq and whole genome methyl-seq, respectively. Both PS-treated fibroblasts and derived hiPSC showed alterations in expression of ESRRB and HNF1A genes and circuits involved in the pluripotency of stem cells, as well as in pathways involved in cancer, inflammatory disorders, gluconeogenesis, carbohydrate metabolism, innate immunity, and dopaminergic synapse. Similarly, the expression levels of identified key transcriptional and DNA methylation changes (DNMT3A, ESSRB, FAM133CP, HNF1A, SEPTIN7P8, and TTC34) were significantly affected in both PS-exposed fibroblasts and hiPSC. This study illustrates the power of human cellular models of environmental pollution to narrow down and prioritize the list of candidate molecular biomarkers of environmental pollution. This knowledge will facilitate the deciphering of the origins of environmental diseases.

Identification of Two Rare Homozygote Missense Variants in the IRS1 Gene in a Patient With Early Gestational Diabetes: A Case Study

Background: Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications and has a rising prevalence worldwide. Environmental and genetic factors contribute to GDM risk. Describing familial cases of GDM can help identify the disease’s genetic components. Methods: Here, we report the case of an Emirati female patient affected with early GDM and familial history of diabetes with a significant level of insulin resistance. As a first step, we investigated the GCK and HNF1A gene sequences by direct sequencing and then performed a clinical exome sequencing (CES) of the patient’s genomic DNA covering 6,670 genes. Results: Our findings showed the absence of any pathogenic variants in the GCK and HNF1A gene sequences. In addition, the CES excluded all maturity-onset diabetes of the young (MODY)-related genes. However, two rare homozygous variants in the insulin receptor substrate 1 ( IRS1 ) gene were identified: p.Pro948Leu (gnomAD minor allele frequency (MAF) = 7.5 × 10 -5 ) and p.Arg1221Cys (gnomAD MAF = 5.6 × 10 -5 ). These variants were absent in a set of healthy Emirati individuals. Both variants are highly conserved among mammalians but have never previously been reported among the same haplotype or individual. p.Pro948Leu and p.Arg1221Cys are localized close to two important functional phosphorylation sites recognized by PI3K (hTyr941) and SHP2 (hTyr1229), respectively. Moreover, the independent and combined effect of the two variants on protein stability was predicted to be destabilizing. Conclusion: Our investigation emphasized the role of downstream regulators of insulin signaling in GDM pathophysiology and identified IRS1 as a candidate gene to explain chronic insulin resistance. In addition, the patient showed significant health improvement after lifestyle modifications and oral antidiabetic administration, even after withdrawing insulin injections. J Endocrinol Metab. 2022;12(6):188-197 doi: https://doi.org/10.14740/jem842