Pparg promotes differentiation and regulates mitochondrial gene expression in bladder epithelial cells

Ureter development and associated congenital anomalies

Malformations of the ureter are among the most common birth defects in humans. Although some of these anomalies are asymptomatic, others are clinically relevant, causing perinatal lethality or progressing to kidney failure in childhood. The genetic causes and developmental aetiology of ureteral anomalies are difficult to study in humans; however, embryological and genetic analyses in the mouse have provided insights into the complex developmental programmes that govern ureter formation from simple tissue primordia, and the pathological consequences that result from disruption of these programmes. Abnormalities in the formation of the nephric duct and ureteric bud lead to changes in the number of ureters (and kidneys), whereas the formation of ectopic ureteric buds, failure of the nephric duct to target the cloaca or failure of the distal ureter to mature underlie vesicoureteral reflux, ureter ectopia, ureterocoele and subsequent hydroureter. Alterations in ureter specification, early growth or cyto-differentiation programmes have now also been associated with various forms of perinatal hydroureter and hydronephrosis as a consequence of functional obstruction. The characterization of cellular processes and molecular drivers of ureterogenesis in the mouse may not only aid understanding of the aetiology of human ureteral anomalies, improve prognostication and benefit the development of therapeutic strategies, but may also prove important for efforts to generate a bioartificial organ.

Differentiation of human pluripotent stem cells into urothelial organoids via transient activation of WNT signaling

The cloaca is a transient structure that forms in the terminal hindgut giving rise to the rectum dorsally and the urogenital sinus ventrally. Similarly, human hindgut cultures derived from human pluripotent stem cells generate human colonic organoids (HCOs) which also contain co-developing urothelial tissue. In this study, our goal was to identify pathways involved in cloacal patterning and apply this to human hindgut cultures. RNA sequencing (RNA-seq) data comparing dorsal versus ventral cloaca in e10.5 mice revealed that WNT signaling was elevated in the ventral versus dorsal cloaca. Inhibition of WNT signaling in hindgut cultures maintained their differentiation toward colonic organoids. WNT activation promoted differentiation toward human urothelial organoids (HUOs). HUOs contained developmental stage specific cell types present in mammalian urothelial tissue including co-developing mesenchyme. Therefore, HUOs offer a powerful in vitro model for dissecting the regulatory pathways that control the dynamic emergence of stage specific cell types within the human urothelium.

Targeting RBP4-STRA6 retinol signaling disrupts adipose-prostate crosstalk: A novel strategy to suppress basal cell plasticity in androgen deprivation

Metabolic rewiring is a starter for lineage plasticity, which is an important driver of prostate development, tumorigenesis and treatment resistance. Androgen-targeted therapies are central to prostate cancer (PCa) management, yet the mechanisms leading prostate development-particularly the metabolic signaling within basal cells during treatment-remain poorly understood. To fulfill this gap, we used multiple models to reveal the metabolic alterations in prostate basal cells. Our study reveals the role of the RBP4-STRA6 axis in modulating retinol metabolism and transporting retinol from adipocyte into prostate cells, contributing to prostate development and basal cell differentiation during androgen deprivation. Through multi-omics analyses, we demonstrate that RBP4-STRA6 axis dependent retinol metabolism is increased with androgen deprivation. Retinol metabolism rewiring is modulated by the androgen receptor (AR) and can regulate basal cell plasticity under androgen deprivation therapy (ADT). Retinol metabolism maintains prostate basal cell lineage plasticity during hormone therapy through the PPARγ signaling pathway, compensating for the AR signaling pathway inhibition by sustaining energy homeostasis and promoting basal cell differentiation. Notably, we identified a basal cell cluster (BC5) characterized by high Retinol metabolism and activated PPARγ signaling pathway, which plays a crucial role in basal-luminal differentiation and prostate growth. This study underscores the importance of RBP4-STRA6 dependent Retinol metabolism, mediating the crosstalk between adipocytes and prostate basal cells, in maintaining prostate development during hormone therapy and provides a foundation for future clinical interventions and diet strategies aimed at enhancing the sensitivity of androgen deprivation in prostate diseases.

PPARγ promotes urothelial remodeling during urinary tract obstruction

Urinary tract obstruction (UTO) is a common cause of kidney injury that can result in chronic kidney disease and end-stage renal disease. Heterogeneity in the extent of obstructive renal damage in humans with UTO implies the existence of unknown mechanisms that protect against or accelerate kidney injury. Prior studies show that congenital and acquired UTO initiate a conserved, protective program of renal urothelium remodeling that culminates in expansion of uroplakin (UPK)+ cells to promote renal structural integrity. However, the cellular and molecular mechanisms that regulate UPK expression in the renal urothelium are unknown. Peroxisome proliferator-activated receptor γ (PPARγ) drives urothelial differentiation and UPK expression in other tissues but has not been investigated in the renal urothelium. Here we demonstrate that activation of PPARγ in UPK+ cells is critical for UTO-induced renal urothelium remodeling. Conditional deletion of Pparg perturbs UPK expression and accelerates parenchymal thinning during UTO, while conditional activation of PPARγ increases UPK expression and results in parenchymal preservation. This study underscores the significance of renal urothelium during UTO and shows that UTO-induced renal urothelial remodeling is achieved through activation of PPARγ. These findings form the foundation for future studies that will determine the therapeutic utility of PPARγ agonists during congenital and acquired UTO.

PPARG contributes to urothelial integrity in the murine ureter by activating the expression of Shh and superficial cell-specific genes

The urothelium is a stratified epithelium with an important barrier function in the urinary drainage system. The differentiation and maintenance of the three major urothelial cell types (basal, intermediate and superficial cells) is incompletely understood. Here, we show that mice with a conditional deletion of the transcription factor gene peroxisome proliferator activated receptor gamma (Pparg) in the ureteric epithelium have a dilated ureter at postnatal stages with a urothelium consisting of a layer of undifferentiated luminal cells and a layer of proliferating basal cells. Molecular analysis of fetal stages revealed that the expression of a large number of genes is not activated in superficial cells and that of a few genes, including Shh, is not activated in intermediate and basal cells. Pharmacological activation of SHH signaling in explant cultures of perinatal Pparg-deficient ureters reduced ureteral width and urothelial cell number to normal levels, increased the number of intermediate cells and slightly reduced basal cell proliferation. Our data suggest that PPARG independently activates the expression of structural genes in superficial cells and of Shh in basal and intermediate cells, and that both functions contribute to urothelial integrity.

Epithelial and mesenchymal compartments of the developing bladder and urethra display spatially distinct gene expression patterns

The lower urinary tract is comprised of the bladder and urethra and develops from the cloaca, a transient endoderm-derived structure formed from the caudal hindgut. After cloacal septation to form the urogenital sinus and anorectal tract, the bladder gradually develops from the anterior portion of the urogenital sinus while the urethra elongates distally into the genital tubercle. The bladder is a target for regenerative and reconstructive therapies but engineering an impermeable bladder epithelial lining has proven challenging. Urethral epithelial function, including its role as an active immune barrier, is poorly studied and neglected in regenerative therapy. A deeper understanding of epithelial patterning of the urogenital sinus by the surrounding mesenchyme, also accounting for sex-specific differences, can inform regenerative therapies. In this study, we identified spatially distinct genes in the epithelial and mesenchymal compartments of the developing mouse bladder and urethra that could be potential drivers of patterning in the lower urinary tract. Our data revealed spatially restricted domains of transcription factor expression in the epithelium that corresponded with bladder or urethra-specific differentiation. Additionally, we identified the genes Wnt2, Klf4 and Pitx2 that localize to the mesenchyme of the developing bladder and could be potential drivers of bladder differentiation. Our data revealed an increase in the expression of several chemokine genes including Cx3cl1 and Cxcl14 in the developing urethral epithelium that correlated with an increase in epithelial-associated macrophages in the urethra. A survey of sex-specific differences in epithelial and mesenchymal compartments revealed several differentially expressed genes between the male and female urethra but few sex-specific differences in bladder. By comparing spatially distinct gene expression in the developing lower urinary tract, our study provides insights into the divergent differentiation trajectories of the fetal bladder and urethra that establish their adult functions.

Exploring the molecular mechanism of Dioscorea alata L. for the treatment of menstrual disorders using network pharmacology and molecular docking

Menstrual disorders (MDs), including premenstrual syndrome, amenorrhea, and dysmenorrhea, affect women globally. Dioscorea alata L., a traditional yam species, has been used medicinally, but its potential in treating MDs remains understudied. This study employs a network pharmacology approach to examine the effects of D. alata's secondary metabolites on MDs via multi-target mechanisms. Compounds were identified from literature and PubChem, while disease-related targets were gathered from GeneCards, DisGeNET, and CTD databases. Swiss target prediction was used to link compounds to targets. A protein-protein interaction (PPI) network was constructed using STRING, and Gene Ontology (GO) and KEGG enrichment analyses were conducted to predict functional pathways. Eighteen bioactive compounds and 120 therapeutic targets specific to MDs were identified. KEGG analysis revealed 20 significant pathways related to menstrual disturbances. Among the 120 targets, TNF α, PPARG, ESR1, and AKT1 were highlighted as key therapeutic targets. Molecular docking showed strong interactions between Daidzein and ESR1, Diosgenin and TNF α, Alatanin and AKT1, and PPARG. The findings suggest that D. alata's bioactive compounds, such as Diosgenin, Daidzein, Genistin, Cycloartane, and Alatanin, could modulate pathways involved in ovarian follicle formation, hormone regulation, estrogen receptor signaling, and the stress-activated MAP kinase pathway. This study provides new insights into the multi-target potential of D. alata for treating menstrual disorders, supporting further investigation and therapeutic development.

Interstitial Cystitis: a phenotype and rare variant exome sequencing study: Interstitial Cystitis: a phenotype and exome sequencing study

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a poorly understood and underdiagnosed syndrome of chronic bladder/pelvic pain with urinary frequency and urgency. Though IC/BPS can be hereditary, little is known of its genetic etiology. Using the eMERGE data, we confirmed known phenotypic associations such as gastroesophageal reflux disease and irritable bowel syndrome and detected new associations, including osteoarthrosis/osteoarthritis and Barrett's esophagus. An exome wide ultra-rare variants analysis in 348 IC/BPS and 11,981 controls extended the previously reported association with ATP2C1 and ATP2A2, implicated in Mendelian desquamating skin disorders, but did not provide evidence for other previously proposed pathogenic pathways such as bladder development, nociception or inflammation. Pathway analysis detected new associations with "anaphase-promoting complex-dependent catabolic process", the "regulation of MAPK cascade" and "integrin binding". These findings suggest perturbations in biological networks for epithelial integrity and cell cycle progression in IC/BPS pathogenesis, and provide a roadmap for its future investigation.

Liver Mitochondrial Morphology and Gene Expression as Markers of Liver Reserve: Prognostic Implications for Native Liver Survival in Biliary Atresia

PURPOSE

Hepatocyte mitochondrial morphology and gene expression were compared between biliary atresia (BA), infantile cholestasis (IC), and normal liver (NL) as prognostic indicators.

METHODS

Specimens of liver at portoenterostomy (PE) for BA, from intrahepatic bile duct paucity patients for IC, and from choledochal cyst or hepatoblastoma patients for NL were collected prospectively (P) beginning in 2021 (P-BA = 11, P-IC = 9, P-NL = 7) and retrospectively (R) from paraffin-embedded tissue going back to 1981 (R-BA = 25, R-IC = 9, R-NL = 4). The P-cohort had transmission electron microscopy (TEM) to image mitochondria, immunoblotting for heat shock protein 60 (HSP60), and quantitative PCR (qPCR) for HSP60 and mitochondrial functional genes. Both cohorts had immunofluorescence for HSP60 quantified as a ratio to albumin-positive hepatocytes (ALB) with HSP60/ALB<1.0 as a cutoff limit using ImageJ.

RESULTS

HSP60 was significantly lower in BA/IC than NL on qPCR (BA: p < 0.01, IC: p < 0.05) and lower in BA than IC/NL on immunoblotting (p < 0.05). HSP60/ALB was significantly lower in BA than NL/IC (p < 0.001). Despite BA subjects being matched for types of BA and ages at PE, HSP60/ALB did not correlate with jaundice clearance (JC; T-Bil<1.2 mg/dL) but was significantly higher in native liver survivors (NLS) after PE compared with liver transplant (LTx) cases (p < 0.05) and significantly lower in LTx cases achieving JC than NLS achieving JC (p < 0.05). TEM showed BA had significantly more mitochondrial inclusion bodies (p < 0.05) and significantly larger cristae (p < 0.01) than IC/NL. qPCR in BA showed significant repression of mitochondrial functional genes for mRNA stabilization and energy facilitation.

CONCLUSION

HSP60/ALB correlates with NLS after PE for BA.

LEVEL OF EVIDENCE

II.

Human Umbilical Cord-Mesenchymal Stem Cells Combined With Low Dosage Nintedanib Rather Than Using Alone Mitigates Pulmonary Fibrosis in Mice

Pulmonary fibrosis (PF) is a lethal pathological change of fibrotic interstitial lung diseases (ILDs) with abundant fibroblasts proliferation after severely or continually alveolar epithelial cells (AECs) injury. Barely therapies are helpful for PF. Here we use bleomycin intratracheally injection to model PF with or without human umbilical cord-mesenchymal stem cells (hUC-MSCs) and/or nintedanib intervention. RNA-Seq followed with real-time PCR and western blot were used to find out the specific possible mechanisms of the effects of hUC-MSC and nintedanib on PF. Immunostaining, cell counting kit-8 (CCK-8), and 5-bromo-2'-deoxyuridine (BrdU) incorporation assay were used to detect the cell proliferation in vivo or in vitro separately. We found that hUC-MSCs alone had prophylactic, but not therapeutic effects on bleomycin induced mouse PF. Nevertheless, the combination therapy of hUC-MSCs and low-dose nintedanib significantly improved survival and reversed lung fibrosis in PF model mice. The factors secreted by hUC-MSCs have promotional effects on the proliferation both of fibroblasts and AECs. Nintedanib could hamper the facilitation of fibroblasts caused by hUC-MSCs without influence on AECs proliferation, which might be related with the inhibition on FGFR, PDGFR, and VEGFR activities. Our study indicated that the combination therapy of hUC-MSCs and nintedanib should be a promising strategy for PF.

Identification of epithelial-related artificial neural network prognostic models for the prediction of bladder cancer prognosis through comprehensive analysis of single-cell and bulk RNA sequencing

Background

Bladder cancer (BLCA) presents as a heterogeneous epithelial malignancy. Progress in the early detection and effective treatment of BLCA relies heavily on the identification of novel biomarkers. Therefore, the primary goal of this study is to pinpoint potential biomarkers for BLCA through the fusion of single-cell RNA sequencing and RNA sequencing assessments. Furthermore, the aim is to establish practical clinical prognostic models that can facilitate accurate categorization and individualized therapy for patients.

Methods

In this research, training sets were acquired from the TCGA database, whereas validation sets (GSE32894) and single-cell datasets (GSE135337) were extracted from the GEO database. Single-cell analysis was utilized to obtain characteristic subpopulations along with their associated marker genes. Subsequently, a novel BLCA subtype was identified within TCGA-BLCA. Furthermore, an artificial neural network prognostic model was constructed within the TCGA-BLCA cohort and subsequently verified utilizing a validation set. Two machine learning algorithms were employed to screen hub genes. QRT-qPCR was performed to detect the gene expression levels utilized in the construction of prognostic models across various cell lines. Additionally, the cMAP database and molecular docking were utilized for searching small molecule drugs.

Results

The results of single-cell analysis revealed the presence of epithelial cells in multiple subpopulations, with 1579 marker genes selected for subsequent investigations. Subsequently, four epithelial cell subtypes were identified within the TCGA-BLCA cohort. Notably, cluster A exhibited a significant survival advantage. Concurrently, an artificial neural network prognostic model comprising 17 feature genes was constructed, accurately stratifying patient risk. Patients categorized in the low-risk group demonstrated a considerable survival advantage. The ROC analysis suggested that the model has strong prognostic ability. Furthermore, the findings of the validation group align consistently with those from the training group. Two types of machine learning algorithms screened NFIC as hub genes. Forskolin, a small molecule drug that binds to NFIC, was identified by employing a cMAP database and molecular docking.

Conclusion

The analysis results supplement the research on the role of epithelial cells in BLCA. An artificial neural network prognostic model containing 17 characteristic genes demonstrates the capability to accurately stratify patient risk, thereby potentially improving clinical decision-making and optimizing personalized therapeutic approaches.

Mitochondrial viability in neurogenic bladder urothelium after sigmoidocolocystoplasty. Implications for persistent vesicoureteral reflux

PURPOSE

We investigated whether inflammatory cell infiltration (ICI), fibrosis, and mitochondrial viability of the neurogenic bladder urothelium are involved in the mechanism of persistent vesicoureteral reflux (VUR) after sigmoidocolocystoplasty (SCP).

METHODS

Bladder biopsies obtained 1994-2023 from 62 neurogenic bladder patients were examined by hematoxylin and eosin for ICI, Masson's trichrome for fibrosis, and immunofluorescence for urothelial growth differentiation factor 15 (GDF15; a mitochondrial stress-responsive cytokine) (positive/negative) and heat shock protein 60 (HSP60; a mitochondrial matrix marker) (strong ≥ 50%/weak≤ 50%) expression. GDF15 + /weak HSP60 indicated compromised mitochondrial viability. Cystometry measured neobladder compliance/capacity.

RESULTS

Mean ages (years) at SCP and bladder biopsies were 9.4 ± 4.6 and 14.2 ± 7.1, respectively. VUR was present in 38/62 patients (51 ureters) at SCP and resolved with SCP alone in 4/38 patients, with SCP and ureteroneocystostomy in 17/38, and persisted in 17/38. Fibrosis was significantly denser in GDF15 + (n = 24)/weak HSP60 (n = 31) compared with GDF15- (n = 38)/strong HSP60 (n = 31) (p < 0.001 and p < 0.01, respectively). Differences in ICI were significant for GDF15 + vs. GDF15- (p < 0.05) but not for HSP60. Patients with VUR after SCP had higher incidence of GDF15 + /weak HSP60 compared with cases without VUR (p < 0.05 and p < 0.001, respectively).

CONCLUSION

Viability of mitochondria appears to be compromised with possible etiologic implications for VUR persisting after SCP.

Rosiglitazone and trametinib exhibit potent anti-tumor activity in a mouse model of muscle invasive bladder cancer

Muscle invasive bladder cancers (BCs) can be divided into 2 major subgroups-basal/squamous (BASQ) tumors and luminal tumors. Since Pparg has low or undetectable expression in BASQ tumors, we tested the effects of rosiglitazone, Pparg agonist, in a mouse model of BASQ BC. We find that rosiglitazone reduces proliferation while treatment with rosiglitazone plus trametinib, a MEK inhibitor, induces apoptosis and reduces tumor volume by 91% after 1 month. Rosiglitazone and trametinib also induce a shift from BASQ to luminal differentiation in tumors, which our analysis suggests is mediated by retinoid signaling, a pathway known to drive the luminal differentiation program. Our data suggest that rosiglitazone, trametinib, and retinoids, which are all FDA approved, may be clinically active in BASQ tumors in patients.

Botanical formulation HX110B ameliorates PPE-induced emphysema in mice via regulation of PPAR/RXR signaling pathway

Chronic obstructive pulmonary disease (COPD), an inflammatory lung disease, causes approximately 3 million deaths each year; however, its pathological mechanisms are not fully understood. In this study, we examined whether HX110B, a mixture of Taraxacum officinale, Dioscorea batatas, and Schizonepeta tenuifolia extracts, could suppress porcine pancreatic elastase (PPE)-induced emphysema in mice and its mechanism of action. The therapeutic efficacy of HX110B was tested using a PPE-induced emphysema mouse model and human bronchial epithelial cell line BEAS-2B. In vivo data showed that the alveolar wall and air space expansion damaged by PPE were improved by HX110B administration. HX110B also effectively suppresses the expression levels of pro-inflammatory mediators including IL-6, IL-1β, MIP-2, and iNOS, while stimulating the expression of lung protective factors such as IL-10, CC16, SP-D, and sRAGE. Moreover, HX110B improved the impaired OXPHOS subunit gene expression. In vitro analysis revealed that HX110B exerted its effects by activating the PPAR-RXR signaling pathways. Overall, our data demonstrated that HX110B could be a promising therapeutic option for COPD treatment.

Integrated analysis of single-cell and bulk RNA sequencing data reveals a myeloid cell-related regulon predicting neoadjuvant immunotherapy response across cancers

BACKGROUND

Immunotherapy has brought about a paradigm shift in the treatment of cancer. However, the majority of patients exhibit resistance or become refractory to immunotherapy, and the underlying mechanisms remain to be explored.

METHODS

Sing-cell RNA sequencing (scRNA‑seq) datasets derived from 1 pretreatment and 1 posttreatment achieving pathological complete response (pCR) patient with lung adenocarcinoma (LUAD) who received neoadjuvant immunotherapy were collected, and pySCENIC was used to find the gene regulatory network (GRN) between cell types and immune checkpoint inhibitor (ICI) response. A regulon predicting ICI response was identified and validated using large‑scale pan-cancer data, including a colorectal cancer scRNA‑seq dataset, a breast cancer scRNA‑seq dataset, The Cancer Genome Atlas (TCGA) pan-cancer cohort, and 5 ICI transcriptomic cohorts. Symphony reference mapping was performed to construct the myeloid cell map.

RESULTS

Thirteen major cluster cell types were identified by comparing pretreatment and posttreatment patients, and the fraction of myeloid cells was higher in the posttreatment group (19.0% vs. 11.8%). A PPARG regulon (containing 23 target genes) was associated with ICI response, and its function was validated by a colorectal cancer scRNA‑seq dataset, a breast cancer scRNA‑seq dataset, TCGA pan-cancer cohort, and 5 ICI transcriptomic cohorts. Additionally, a myeloid cell map was developed, and cluster I, II, and III myeloid cells with high expression of PPARG were identified. Moreover, we constructed a website called PPARG ( https://pparg.online/PPARG/ or http://43.134.20.130:3838/PPARG/ ), which provides a powerful discovery tool and resource value for researchers.

CONCLUSIONS

The PPARG regulon is a predictor of ICI response. The myeloid cell map enables the identification of PPARG subclusters in public scRNA-seq datasets and provides a powerful discovery tool and resource value.

Insulin receptor signaling engages bladder urothelial defenses that limit urinary tract infection

Urinary tract infections (UTIs) commonly afflict people with diabetes. To better understand the mechanisms that predispose diabetics to UTIs, we employ diabetic mouse models and altered insulin signaling to show that insulin receptor (IR) shapes UTI defenses. Our findings are validated in human biosamples. We report that diabetic mice have suppressed IR expression and are more susceptible to UTIs caused by uropathogenic Escherichia coli (UPEC). Systemic IR inhibition increases UPEC susceptibility, while IR activation reduces UTIs. Localized IR deletion in bladder urothelium promotes UTI by increasing barrier permeability and suppressing antimicrobial peptides. Mechanistically, IR deletion reduces nuclear factor κB (NF-κB)-dependent programming that co-regulates urothelial tight junction integrity and antimicrobial peptides. Exfoliated urothelial cells or urine samples from diabetic youths show suppressed expression of IR, barrier genes, and antimicrobial peptides. These observations demonstrate that urothelial insulin signaling has a role in UTI prevention and link IR to urothelial barrier maintenance and antimicrobial peptide expression.

Human Pluripotent Stem Cell Derived Organoids Reveal a Role for WNT Signaling in Dorsal-Ventral Patterning of the Hindgut

The cloaca is a transient structure that forms in the terminal hindgut giving rise to the rectum dorsally and the urogenital sinus ventrally. Similarly, human hindgut cultures derived from human pluripotent stem cells generate human colonic organoids (HCOs) which also contain co-developing urothelial tissue. In this study, our goal was to identify pathways involved in cloacal patterning and apply this to human hindgut cultures. RNA-seq data comparing dorsal versus ventral cloaca in e10.5 mice revealed that WNT signaling was elevated in the ventral versus dorsal cloaca. Inhibition of WNT signaling in hindgut cultures biased their differentiation towards a colorectal fate. WNT activation biased differentiation towards a urothelial fate, giving rise to human urothelial organoids (HUOs). HUOs contained cell types present in human urothelial tissue. Based on our results, we propose a mechanism whereby WNT signaling patterns the ventral cloaca, prior to cloacal septation, to give rise to the urogenital sinus.

Transcription factor Tcf21 modulates urinary bladder size and differentiation

Urinary bladder organogenesis requires coordinated cell growth, specification, and patterning of both mesenchymal and epithelial compartments. Tcf21, a gene that encodes a helix-loop-helix transcription factor, is specifically expressed in the mesenchyme of the bladder during development. Here we show that Tcf21 is required for normal development of the bladder. We found that the bladders of mice lacking Tcf21 were notably hypoplastic and that the Tcf21 mutant mesenchyme showed increased apoptosis. There was also a marked delay in the formation of visceral smooth muscle, accompanied by a defect in myocardin (Myocd) expression. Interestingly, there was also a marked delay in the formation of the basal cell layer of the urothelium, distinguished by diminished expression of Krt5 and Krt14. Our findings suggest that Tcf21 regulates the survival and differentiation of mesenchyme cell-autonomously and the maturation of the adjacent urothelium non-cell-autonomously during bladder development.

The urothelial gene regulatory network: understanding biology to improve bladder cancer management

The urothelium is a stratified epithelium composed of basal cells, one or more layers of intermediate cells, and an upper layer of differentiated umbrella cells. Most bladder cancers (BLCA) are urothelial carcinomas. Loss of urothelial lineage fidelity results in altered differentiation, highlighted by the taxonomic classification into basal and luminal tumors. There is a need to better understand the urothelial transcriptional networks. To systematically identify transcription factors (TFs) relevant for urothelial identity, we defined highly expressed TFs in normal human bladder using RNA-Seq data and inferred their genomic binding using ATAC-Seq data. To focus on epithelial TFs, we analyzed RNA-Seq data from patient-derived organoids recapitulating features of basal/luminal tumors. We classified TFs as "luminal-enriched", "basal-enriched" or "common" according to expression in organoids. We validated our classification by differential gene expression analysis in Luminal Papillary vs. Basal/Squamous tumors. Genomic analyses revealed well-known TFs associated with luminal (e.g., PPARG, GATA3, FOXA1) and basal (e.g., TP63, TFAP2) phenotypes and novel candidates to play a role in urothelial differentiation or BLCA (e.g., MECOM, TBX3). We also identified TF families (e.g., KLFs, AP1, circadian clock, sex hormone receptors) for which there is suggestive evidence of their involvement in urothelial differentiation and/or BLCA. Genomic alterations in these TFs are associated with BLCA. We uncover a TF network involved in urothelial cell identity and BLCA. We identify novel candidate TFs involved in differentiation and cancer that provide opportunities for a better understanding of the underlying biology and therapeutic intervention.

How Do Molecular Classifications Affect the Neoadjuvant Treatment of Muscle-Invasive Urothelial Carcinoma?

Despite the significant improvements in the field of oncological treatments in recent decades, and the advent of targeted therapies and immunotherapy, urothelial carcinoma of the bladder remains a highly heterogeneous and difficult-to-treat neoplasm with a poor prognosis. In this context, owing to the new methods of genomic sequencing, numerous studies have analyzed the genetic features of muscle-invasive bladder cancer, providing a consensus set of molecular classes, to identify malignancies that may respond better to specific treatments (standard chemotherapy, immunotherapy, target therapy, local-regional treatment, or combinations) and improve the survival. The aim of the current review is to provide an overview of the current status of the molecular landscape of muscle-invasive bladder cancer, focusing our attention on therapeutic and prognostic implications in order to select the most effective and tailored therapeutic regimen for the individual patient.

Integrated investigation and experimental validation of PPARG as an oncogenic driver: implications for prognostic assessment and therapeutic targeting in hepatocellular carcinoma

Peroxisome proliferator-activated receptor gamma (PPARG), a key transcription factor involved in lipid metabolism and glucose homeostasis, has been implicated in various types of cancer. However, its precise role in cancer remains unclear. In this study, we conducted a comprehensive pan-cancer analysis of PPARG expression using various types of cancer obtained from public databases. We observed significant heterogeneity in PPARG expression across different types of cancer. The association between PPARG expression and patient prognosis was investigated using Cox proportional hazards regression models and survival analysis. Clinical features and protein expression levels in the cohort showed that PPARG expression was strongly associated, suggesting its potential as a therapeutic target. We also evaluated the prognostic potential of PPARG by analyzing immune infiltration and genomic stability. We experimentally validated the potential of PPARG as a therapeutic target by analyzing drug sensitivity profiles, molecular docking simulations, and in vitro cell proliferation assays associated with PPARG expression. We identified common expression patterns of PPARG with other genes involved in key carcinogenic pathways. This provides deeper insights into the molecular mechanisms underlying its carcinogenic role. Additionally, functional enrichment analysis revealed significant enrichment of genes related to drug metabolism, cell proliferation, and immune response pathways associated with PPARG. Our findings highlight the importance of PPARG in the broader biology of cancer and suggest its potential as a diagnostic and therapeutic target for specific types of cancer. The results of our study provide strong support for the potential role of PPARG as a promising prognostic biomarker and immunotherapeutic target across various types of cancer.

Distinct effects of Fgf7 and Fgf10 on the terminal differentiation of murine bladder urothelium revealed using an organoid culture system

BACKGROUND

Dysregulation of the terminal differentiation of bladder urothelium is associated with the pathogenesis of urinary tract disorders. Fibroblast growth factor (Fgf)7 and Fgf10 stimulate urothelial proliferation; however, their roles in cellular differentiation remain unclear. In this study, we used an organoid system to investigate the roles of these Fgfs in regulating bladder urothelium differentiation and identify their distribution patterns in the mouse bladder.

METHODS

Adult bladder epithelia (AdBE) isolated from adult mouse bladder tissues (AdBTs) were used to culture adult bladder organoids (AdBOs) in the presence of Fgf7 and Fgf10. The differentiation status of the cells in AdBTs, AdBEs, AdBOs, and neonatal bladder tissues (NeoBTs) was analyzed via quantitative real-time-PCR for the presence of undifferentiated cell markers (Krt5, Trp63, and Krt14) and differentiated cell markers (Krt20, Upk1a, Upk2, and Upk3a). Organoid cell proliferation was assessed by counting cell numbers using the trypan blue method. The effects of Fgf7 and Fgf10 on organoid differentiation were assessed using different doses of Fgfs, and the involvement of peroxisome proliferator-activated receptor γ (PPARγ) signaling in these processes was tested by introducing a PPARγ agonist (Rosiglitazone) and antagonist (T0070907) to the culture. The expression patterns of Fgf7 and Fgf10 were examined via in situ hybridization of AdBTs.

RESULTS

AdBOs showed higher expression of undifferentiated cell markers and lower expression of differentiated cell markers than AdBTs, NeoBTs, and AdBEs, indicating the relatively immature state of AdBOs. Differentiation of AdBOs was enhanced by Rosiglitazone and Fgf7, suggesting an interplay of intracellular signals between Fgf7 and PPARγ. Co-addition of T0070907 suppressed Fgf7-mediated differentiation, demonstrating that PPARγ is activated downstream of Fgf7 to promote cellular differentiation into umbrella cells. Furthermore, we found that Fgf7 is predominantly expressed in the umbrella cells of the urothelium, whereas Fgf10 is predominantly expressed in the urothelium and stroma of AdBTs.

CONCLUSIONS

We demonstrated that unlike Fgf10, Fgf7 induces cellular differentiation via PPARγ activity and has a unique tissue distribution pattern in the adult bladder. Further studies on the Fgf7-PPARγ signaling axis would provide insights into the differentiation mechanisms toward functional umbrella cells and the pathogenesis of several urinary tract diseases.

Combined Mek inhibition and Pparg activation Eradicates Muscle Invasive Bladder cancer in a Mouse Model of BBN-induced Carcinogenesis

Bladder cancers (BCs) can be divided into 2 major subgroups displaying distinct clinical behaviors and mutational profiles: basal/squamous (BASQ) tumors that tend to be muscle invasive, and luminal/papillary (LP) tumors that are exophytic and tend to be non-invasive. Pparg is a likely driver of LP BC and has been suggested to act as a tumor suppressor in BASQ tumors, where it is likely suppressed by MEK-dependent phosphorylation. Here we tested the effects of rosiglitazone, a Pparg agonist, in a mouse model of BBN-induced muscle invasive BC. Rosiglitazone activated Pparg signaling in suprabasal epithelial layers of tumors but not in basal-most layers containing highly proliferative invasive cells, reducing proliferation but not affecting tumor survival. Addition of trametinib, a MEK inhibitor, induced Pparg signaling throughout all tumor layers, and eradicated 91% of tumors within 7-days of treatment. The 2-drug combination also activated a luminal differentiation program, reversing squamous metaplasia in the urothelium of tumor-bearing mice. Paired ATAC-RNA-seq analysis revealed that tumor apoptosis was most likely linked to down-regulation of Bcl-2 and other pro-survival genes, while the shift from BASQ to luminal differentiation was associated with activation of the retinoic acid pathway and upregulation of Kdm6a, a lysine demethylase that facilitates retinoid-signaling. Our data suggest that rosiglitazone, trametinib, and retinoids, which are all FDA approved, may be clinically active in BASQ tumors in patients. That muscle invasive tumors are populated by basal and suprabasal cell types with different responsiveness to PPARG agonists will be an important consideration when designing new treatments.

Tetrastigma polysaccharide reprogramming of tumor-associated macrophages via PPARγ signaling pathway to play antitumor activity in breast cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Tetrastigma Hemsleyanum Diels et Gilg (SYQ) is a typical She ethnomedicine that has been used in anti-tumor treatment in Chinese folklore. The polysaccharide of SYQ (SYQ-PA) has been reported to have antioxidant and anti-inflammatory effects, but the effect and mechanism on antitumor is still unclear.

AIM OF THE STUDY

To investigate the activity and mechanism of SYQ-PA against breast cancer in vitro and in vivo.

MATERIALS AND METHODS

In this study, different stages of MMTV-PYMT mice, which at 4-week-old and 8-week-old representative the transition from hyperplasia to late carcinoma, were used to investigate the potential effect of SYQ-PA of breast cancer development in vivo. The mechanism was explored with IL4/13-induced peritoneal macrophages model. Flow cytometry assay was employed to analysis the change of tumor microenvironment and the macrophages typing. The inhibition of the condition medium from macrophages on breast cancer cells was detected with xCELLigence system detection. The inflammation factors were tested with cytometric bead array. Co-culture system was used to detect the cell migration and invasion. In addition, the underlying mechanism was investigated using RNAseq analysis, Q-PCR and Western blot, and the PPARγ inhibitor was used to verify the mechanism.

RESULTS

SYQ-PA significantly attenuated the process of breast primary tumor growth and reduced the infiltration of TAMs accompanied promoting the polarization of M1 phenotype in MMTV-PyMT mice. Then in vitro studies showed that SYQ-PA promoted macrophages polarization form IL4/13 induced M2 toward to the anti-tumor M1 phenotypes, and the conditioned medium (CM) from the induced macrophages inhibited the proliferation of breast cancer cells. At the same time, SYQ-PA treated macrophages inhibited the migration and invasion of 4T1 in the co-culture system. Further results indicated that SYQ-PA suppressed the release of anti-inflammatory factors and promoted the production of inflammatory cytokines which may induce M1 macrophage polarization and inhibit breast cancer cell proliferation. Subsequently, the underlying mechanism analysis based on RNAseq and molecular assays indicated that SYQ-PA inhibited PPARγ expression and regulated downstream NF-κB in macrophages. After treated with PPARγ inhibitor, T0070907, the effect of SYQ-PA was decreased, or even disappeared. As the downstream, the expression of β-catenin was also inhibited obviously, those above all contribute the process of SYQ-PA induced M1 macrophages polarization.

CONCLUSIONS

Collectively, SYQ-PA was observed inhibited breast cancer, at least in part, via PPARγ activation- and β-catenin-mediated M2 macrophages polarization. These data expound the antitumor effect and mechanism of SYQ-PA, and provide a possible that SYQ-PA can be used as an adjuvant drug for macrophage tumor immunotherapy in breast cancer.

The role of PPARγ in prostate cancer development and progression

Advanced and metastatic prostate cancer is often incurable, but its dependency on certain molecular alterations may provide the basis for targeted therapies. A growing body of research has demonstrated that peroxisome proliferator-activated receptor gamma (PPARγ) is amplified as prostate cancer progresses. PPARγ has been shown to support prostate cancer growth through its roles in fatty acid synthesis, mitochondrial biogenesis, and co-operating with androgen receptor signalling. Interestingly, splice variants of PPARγ may have differing and contrasting roles. PPARγ itself is a highly druggable target, with agonists having been used for the past two decades in treating diabetes. However, side effects associated with these compounds have currently limited clinical use of these drugs in prostate cancer. Further understanding of PPARγ and novel techniques to target it, may provide therapies for advanced prostate cancer.

Cannabidiol as a Promising Therapeutic Option in IC/BPS: In Vitro Evaluation of Its Protective Effects against Inflammation and Oxidative Stress

Several animal studies have described the potential effect of cannabidiol (CBD) in alleviating the symptoms of interstitial cystitis/bladder pain syndrome (IC/BPS), a chronic inflammatory disease of the urinary bladder. However, the effects of CBD, its mechanism of action, and modulation of downstream signaling pathways in urothelial cells, the main effector cells in IC/BPS, have not been fully elucidated yet. Here, we investigated the effect of CBD against inflammation and oxidative stress in an in vitro model of IC/BPS comprised of TNFα-stimulated human urothelial cells SV-HUC1. Our results show that CBD treatment of urothelial cells significantly decreased TNFα-upregulated mRNA and protein expression of IL1α, IL8, CXCL1, and CXCL10, as well as attenuated NFκB phosphorylation. In addition, CBD treatment also diminished TNFα-driven cellular reactive oxygen species generation (ROS), by increasing the expression of the redox-sensitive transcription factor Nrf2, the antioxidant enzymes superoxide dismutase 1 and 2, and hem oxygenase 1. CBD-mediated effects in urothelial cells may occur by the activation of the PPARγ receptor since inhibition of PPARγ resulted in significantly diminished anti-inflammatory and antioxidant effects of CBD. Our observations provide new insights into the therapeutic potential of CBD through modulation of PPARγ/Nrf2/NFκB signaling pathways, which could be further exploited in the treatment of IC/BPS.

FLI1 and FRA1 transcription factors drive the transcriptional regulatory networks characterizing muscle invasive bladder cancer

Bladder cancer is mostly present in the form of urothelium carcinoma, causing over 150,000 deaths each year. Its histopathological classification as muscle invasive (MIBC) and non-muscle invasive (NMIBC) is the most prominent aspect, affecting the prognosis and progression of this disease. In this study, we defined the active regulatory landscape of MIBC and NMIBC cell lines using H3K27ac ChIP-seq and used an integrative approach to combine our findings with existing data. Our analysis revealed FRA1 and FLI1 as two critical transcription factors differentially regulating MIBC regulatory landscape. We show that FRA1 and FLI1 regulate the genes involved in epithelial cell migration and cell junction organization. Knock-down of FRA1 and FLI1 in MIBC revealed the downregulation of several EMT-related genes such as MAP4K4 and FLOT1. Further, ChIP-SICAP performed for FRA1 and FLI1 enabled us to infer chromatin binding partners of these transcription factors and link this information with their target genes. Finally, we show that knock-down of FRA1 and FLI1 result in significant reduction of invasion capacity of MIBC cells towards muscle microenvironment using IC-CHIP assays. Our results collectively highlight the role of these transcription factors in selection and design of targeted options for treatment of MIBC.

Current research and future directions in non-malignant urologic research - proceedings of the annual CAIRIBU meeting

The Annual Collaborating for the Advancement of Interdisciplinary Research (CAIRIBU) Meeting in 2022 highlighted basic, translational, and clinical non-malignant urology research within five main areas affecting the urinary tract: urinary dysfunction due to prostate disease, microbes and infection, bladder function and physiology, neurology and neuromuscular influences and calculi and obstruction. In this paper, we summarize main findings and future directions outlined by CAIRIBU-affiliated scientists who presented as part of the scientific sessions.

CDH1 overexpression predicts bladder cancer from early stage and inversely correlates with immune infiltration

Background

Bladder cancer (BC) seriously endangers public health, but effective biomarkers for BC diagnosis, particularly in the early stage, are still lacking. Identification of reliable biomarkers associated with early-stage BC is of great importance to early treatment and an improved outcome.

Methods

Differentially expressed genes (DEGs) were identified using four publicly available early-stage BC gene-expression profiles. Protein–protein interaction (PPI) and survival analysis for hub genes was evaluated. The correlation between methylation of genes and prognosis was evaluated using the MethSurv database. Co-expressed genes were explored using Cancer Cell Line Encyclopedia database and the corresponding expression were assessed in vitro. The competing endogenous RNA network and the immune cell infiltration in BC were generated using data of The Cancer Genome Atlas.

Results

Ten hub genes of the 213 integrated DEGs were identified, including CDH1, IGFBP3, PPARG, SDC1, EPCAM, ACTA2, COL3A1, TPM1, ACTC1, and ACTN1. CDH1 appeared to increase from tumor initiation stage and negatively correlated with methylation. Six methylated sites in CDH1 indicated a good prognosis and one site indicated an aberrant prognosis. High CDH1 expression was negatively correlated with infiltrations by most immune cells, such as plasmacytoid dendritic cells (pDCs), regulatory T cells, macrophages, neutrophils, DCs, and natural killer cells. CDH1 was highly positively correlated with EPCAM and appeared to be directly regulated by miR-383.

Conclusions

The identified oncogenic alterations provide theoretical support for the development of novel biomarkers to advance early-stage BC diagnosis and personalized therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-01103-7.

Molecular Mechanism of YuPingFeng in the Treatment of Asthma Based on Network Pharmacology and Molecular Docking Technology

Objective

To explore the molecular targets and mechanism of YuPingFeng (YPF) for the treatment of asthma by using network pharmacology and molecular docking.

Methods

The potential active ingredients and relevant targets of YPF were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Asthma-related gene targets were retrieved from GeneCards, OMIM, DrugBank, PharmGKB, and TTD databases. The protein-protein (PPI) network between YPF and asthma common targets was constructed by SRING online database and Cytoscape software. GO and KEGG analyses were performed to explore the complicated molecular biological processes and potential pathways. Finally, a molecular docking approach was carried out to verify the results.

Results

We obtained 100 potential targets of the 35 active ingredients in YPF and 1610 asthma-related targets. 60 YPF-asthma common targets were selected to perform PPI analysis. Seven core genes were screened based on two topological calculation methods. GO and KEGG results showed that the main pathways of YPF in treating asthma include TNF signaling pathway and PI3K-Akt signaling pathway. Finally, the molecular docking results indicated that the key ingredients of YPF had a good affinity with the relevant core genes.

Conclusion

This study reflects the multicomponent, multitarget, and multipathway characteristics of YPF in treating asthma, providing a theoretical and scientific basis for the intervention of asthma by traditional Chinese medicine YPF.

The immune responses to different Uropathogens call individual interventions for bladder infection

Urinary tract infection (UTI) caused by uropathogens is the most common infectious disease and significantly affects all aspects of the quality of life of the patients. However, uropathogens are increasingly becoming antibiotic-resistant, which threatens the only effective treatment option available-antibiotic, resulting in higher medical costs, prolonged hospital stays, and increased mortality. Currently, people are turning their attention to the immune responses, hoping to find effective immunotherapeutic interventions which can be alternatives to the overuse of antibiotic drugs. Bladder infections are caused by the main nine uropathogens and the bladder executes different immune responses depending on the type of uropathogens. It is essential to understand the immune responses to diverse uropathogens in bladder infection for guiding the design and development of immunotherapeutic interventions. This review firstly sorts out and comparatively analyzes the immune responses to the main nine uropathogens in bladder infection, and summarizes their similarities and differences. Based on these immune responses, we innovatively propose that different microbial bladder infections should adopt corresponding immunomodulatory interventions, and the same immunomodulatory intervention can also be applied to diverse microbial infections if they share the same effective therapeutic targets.

Single-cell and spatial mapping Identify cell types and signaling Networks in the human ureter

Tissue engineering offers a promising treatment strategy for ureteral strictures, but its success requires an in-depth understanding of the architecture, cellular heterogeneity, and signaling pathways underlying tissue regeneration. Here, we define and spatially map cell populations within the human ureter using single-cell RNA sequencing, spatial gene expression, and immunofluorescence approaches. We focus on the stromal and urothelial cell populations to enumerate the distinct cell types composing the human ureter and infer potential cell-cell communication networks underpinning the bi-directional crosstalk between these compartments. Furthermore, we analyze and experimentally validate the importance of the sonic hedgehog (SHH) signaling pathway in adult progenitor cell maintenance. The SHH-expressing basal cells support organoid generation in vitro and accurately predict the differentiation trajectory from basal progenitor cells to terminally differentiated umbrella cells. Our results highlight the essential processes involved in adult ureter tissue homeostasis and provide a blueprint for guiding ureter tissue engineering.

Urothelial progenitors in development and repair

Urothelium is a specialized multilayer epithelium that lines the urinary tract from the proximal urethra to the kidney. In addition to proliferation and differentiation during development, urothelial injury postnatally triggers a robust regenerative capacity to restore the protective barrier between the urine and tissue. Mounting evidence supports the existence of dedicated progenitor cell populations that give rise to urothelium during development and in response to injury. Understanding the cellular and molecular basis for urothelial patterning and repair will inform tissue regeneration therapies designed to ameliorate a number of structural and functional defects of the urinary tract. Here, we review the current understanding of urothelial progenitors and the signaling pathways that govern urothelial development and repair. While most published studies have focused on bladder urothelium, we also discuss literature on upper tract urothelial progenitors. Furthermore, we discuss evidence supporting existence of context-specific progenitors. This knowledge is fundamental to the development of strategies to regenerate or engineer damaged or diseased urothelium.

MYBL2 accelerates epithelial-mesenchymal transition and hepatoblastoma metastasis via the Smad/SNAI1 pathway

Hepatoblastoma (HB) accounts for the majority of hepatic malignancies in children. Although the prognosis of patients with HB has improved in past decades, metastasis is an indicator of poor overall survival. Herein, we applied single-cell RNA sequencing to explore the transcriptomic profiling of 25,264 metastatic cells isolated from the lungs of two patients with HB. The transcriptomes uncovered the heterogeneity of malignant cells after metastatic lung colonization, and these cells had varied expression signatures associated with the cell cycle, epithelial-mesenchymal plasticity, and hepatic differentiation. Single-cell regulatory network inference and clustering (SCENIC) was utilized to identify the co-expressed transcriptional factors which regulated and represented the different cell states. We further screened the key factor by bioinformatics analysis and found that MYBL2 upregulation was significantly associated with metastasis and poor prognosis. The relationship between ectopic MYBL2 and metastasis was subsequently proved by immunohistochemistry (IHC) of HB tissues, and the functions of MYBL2 in promoting proliferation, migration, and epithelial-to-mesenchymal transition (EMT) were verified by in vitro and in vivo assays. Importantly, the levels of Smad2/3 phosphorylation and SNAI1 expression were increased in MYBL2-transfected cells. Consequently, these results indicated that the MYBL2-controlled Smad/SNAI1 pathway induced EMT and promoted HB tumorigenesis and metastasis.

Development, regeneration and tumorigenesis of the urothelium

The urothelium of the bladder functions as a waterproof barrier between tissue and outflowing urine. Largely quiescent during homeostasis, this unique epithelium rapidly regenerates in response to bacterial or chemical injury. The specification of the proper cell types during development and injury repair is crucial for tissue function. This Review surveys the current understanding of urothelial progenitor populations in the contexts of organogenesis, regeneration and tumorigenesis. Furthermore, we discuss pathways and signaling mechanisms involved in urothelial differentiation, and consider the relevance of this knowledge to stem cell biology and tissue regeneration.

Arid1a regulates bladder urothelium formation and maintenance

Epigenetic regulation of gene expression plays a central role in bladder urothelium development and maintenance. ATPase-dependent chromatin remodeling is a major epigenetic regulatory mechanism, but its role in the bladder has not been explored. Here, we show the functions of Arid1a, the largest subunit of the SWI/SNF or BAF chromatin remodeling ATPase complex, in embryonic and adult bladder urothelium. Knockout of Arid1a in urothelial progenitor cells significantly increases cell proliferation during bladder development. Deletion of Arid1a causes ectopic cell proliferation in the terminally differentiated superficial cells in adult mice. Consistently, gene-set enrichment analysis of differentially expressed genes demonstrates that the cell cycle-related pathways are significantly enriched in Arid1a knockouts. Gene-set of the polycomb repression complex 2 (PRC2) pathway is also enriched, suggesting that Arid1a antagonizes the PRC2-dependent epigenetic gene silencing program in the bladder. During acute cyclophosphamide-induced bladder injury, Arid1a knockouts develop hyperproliferative and hyperinflammatory phenotypes and exhibit a severe loss of urothelial cells. A Hallmark gene-set of the oxidative phosphorylation pathway is significantly reduced in Aria1a mutants before injury and is unexpectedly enriched during injury response. Together, this study uncovers functions of Arid1a in both bladder progenitor cells and the mature urothelium, suggesting its critical roles in urothelial development and regeneration.

Transcriptome Profiling of Developing Ovine Fat Tail Tissue Reveals an Important Role for MTFP1 in Regulation of Adipogenesis

Fat-tail sheep exhibit a unique trait whereby substantial adipose tissue accumulates in the tail, a phenotype that is advantageous in many agroecological environments. In this study, we conducted histological assays, transcriptome analysis and functional assays to examine morphogenesis, characterize gene expression, and elucidate mechanisms that regulate fat tail development. We obtained the microstructure of tail before and after fat deposition, and demonstrated that measurable fat deposition occurred by the 80-day embryo (E80) stage, earlier than other tissues. Transcriptome profiling revealed 1,058 differentially expressed genes (DEGs) with six markedly different expression trends. GSEA enrichment and other downstream analyses showed important roles for genes and pathways involving in metabolism and that mitochondrial components were specifically overexpressed in the fat tail tissue of the 70-day embryo (E70). One hundred and eighty-three genes were further identified by leading edge gene analysis, among which, 17 genes have been reported in previous studies, including EEF1D, MTFP1, PPP1CA, PDGFD. Notably, the MTFP1 gene was highly correlated with the expression of other genes and with the highest enrichment score and gene expression change. Knockdown of MTFP1 in isolated adipose derived stem cells (ADSCs) inhibited cell proliferation and migration ability, besides, promoted the process of adipogenesis in vitro.

Pioglitazone, Bladder Cancer and the Presumption of Innocence

BACKGROUND

Thiazolidinediones are potent exogenous agonists of PPAR-γ, which augment the effects of insulin to its cellular targets and mainly at the level of adipose tissue. Pioglitazone, the main thiazolidinedione in clinical practice, has shown cardiovascular and renal benefits in patients with type 2 diabetes, durable reduction of glycated hemoglobulin levels, important improvements of several components of the metabolic syndrome and beneficial effects of non-alcoholic fatty liver disease.

OBJECTIVE

Despite all of its established advantages, the controversy for an increased risk of developing bladder cancer, combined with the advent of newer drug classes that achieved major cardiorenal effects have significantly limited its use spreading a persistent shadow of doubt for its future role.

METHODS

Pubmed, Google and Scope databases have been thoroughly searched and relevant studies were selected.

RESULTS

This paper explores thoroughly both in vitro and in vivo (animal models and humans) studies that investigated the possible association of pioglitazone with bladder cancer.

CONCLUSION

Currently the association of pioglitazone with bladder cancer cannot be based on solid evidence. This evidence cannot justify its low clinical administration, especially in the present era of individualised treatment strategies. Definite clarification of this issue is imperative and urgently anticipated from future high quality and rigorous pharmacoepidemiologic research, keeping in mind its unique mechanism of action and its significant pleiotropic effects.

PLK1 inhibition selectively induces apoptosis in ARID1A deficient cells through uncoupling of oxygen consumption from ATP production

Inhibitors of the mitotic kinase PLK1 yield objective responses in a subset of refractory cancers. However, PLK1 overexpression in cancer does not correlate with drug sensitivity, and the clinical development of PLK1 inhibitors has been hampered by the lack of patient selection marker. Using a high-throughput chemical screen, we discovered that cells deficient for the tumor suppressor ARID1A are highly sensitive to PLK1 inhibition. Interestingly this sensitivity was unrelated to canonical functions of PLK1 in mediating G2/M cell cycle transition. Instead, a whole-genome CRISPR screen revealed PLK1 inhibitor sensitivity in ARID1A deficient cells to be dependent on the mitochondrial translation machinery. We find that ARID1A knock-out (KO) cells have an unusual mitochondrial phenotype with aberrant biogenesis, increased oxygen consumption/expression of oxidative phosphorylation genes, but without increased ATP production. Using expansion microscopy and biochemical fractionation, we see that a subset of PLK1 localizes to the mitochondria in interphase cells. Inhibition of PLK1 in ARID1A KO cells further uncouples oxygen consumption from ATP production, with subsequent membrane depolarization and apoptosis. Knockdown of specific subunits of the mitochondrial ribosome reverses PLK1-inhibitor induced apoptosis in ARID1A deficient cells, confirming specificity of the phenotype. Together, these findings highlight a novel interphase role for PLK1 in maintaining mitochondrial fitness under metabolic stress, and a strategy for therapeutic use of PLK1 inhibitors. To translate these findings, we describe a quantitative microscopy assay for assessment of ARID1A protein loss, which could offer a novel patient selection strategy for the clinical development of PLK1 inhibitors in cancer.

The Vulnerability to Methamphetamine Dependence and Genetics: A Case-Control Study Focusing on Genetic Polymorphisms at Chromosomal Region 5q31.3

OBJECTIVES

Methamphetamine (METH) is a central nervous psychostimulant and one of the most frequently used illicit drugs. Numerous genetic loci that influence complex traits, including alcohol abuse, have been discovered; however, genetic analyses for METH dependence remain limited. An increased histone deacetylase 3 (HDAC3) expression has been detected in Fos-positive neurons in the dorsomedial striatum following withdrawal after METH self-administration. Herein, we aimed to systematically investigate the contribution of HDAC3 to the vulnerability to METH dependence in a Han Chinese population.

METHODS

In total, we recruited 1,221 patients with METH dependence and 2,328 age- and gender-matched controls. For genotyping, we selected 14 single nucleotide polymorphisms (SNPs) located within ± 3 kb regions of HDAC3. The associations between genotyped genetic polymorphisms and the vulnerability to METH dependence were examined by single marker- and haplotype-based methods using PLINK. The effects of expression quantitative trait loci (eQTLs) on targeted gene expressions were investigated using the Genotype-Tissue Expression (GTEx) database.

RESULTS

The SNP rs14251 was identified as a significant association signal (χ² = 9.84, P = 0.0017). An increased risk of METH dependence was associated with the A allele (minor allele) of rs14251 [odds ratio (95% CI) = 1.25 (1.09-1.43)]. The results of in silico analyses suggested that SNP rs14251 could be a potential eQTL signal for FCHSD1, PCDHGB6, and RELL2, but not for HDAC3, in various human tissues.

CONCLUSION

We demonstrated that genetic polymorphism rs14251 located at 5q31.3 was significantly associated with the vulnerability to METH dependence in Han Chinese population.

Alterations of Chromatin Regulators in the Pathogenesis of Urinary Bladder Urothelial Carcinoma

Simple Summary

Urinary bladder cancer is one of the ten major cancers worldwide, with higher incidences in males, in smokers, and in highly industrialized countries. New therapies beyond cytotoxic chemotherapy are urgently needed to improve treatment of these tumors. A better understanding of the mechanisms underlying their development may help in this regard. Recently, it was discovered that a group of proteins regulating the state of chromatin and thus gene expression is exceptionally and frequently affected by gene mutations in bladder cancers. Altered function of these mutated chromatin regulators must therefore be fundamental in their development, but how and why is poorly understood. Here we review the current knowledge on changes in chromatin regulators and discuss their possible consequences for bladder cancer development and options for new therapies.

Abstract

Urothelial carcinoma (UC) is the most frequent histological type of cancer in the urinary bladder. Genomic changes in UC activate MAPK and PI3K/AKT signal transduction pathways, which increase cell proliferation and survival, interfere with cell cycle and checkpoint control, and prevent senescence. A more recently discovered additional category of genetic changes in UC affects chromatin regulators, including histone-modifying enzymes (KMT2C, KMT2D, KDM6A, EZH2), transcription cofactors (CREBBP, EP300), and components of the chromatin remodeling complex SWI/SNF (ARID1A, SMARCA4). It is not yet well understood how these changes contribute to the development and progression of UC. Therefore, we review here the emerging knowledge on genomic and gene expression alterations of chromatin regulators and their consequences for cell differentiation, cellular plasticity, and clonal expansion during UC pathogenesis. Our analysis identifies additional relevant chromatin regulators and suggests a model for urothelial carcinogenesis as a basis for further mechanistic studies and targeted therapy development.

Pparg signaling controls bladder cancer subtype and immune exclusion

Pparg, a nuclear receptor, is downregulated in basal subtype bladder cancers that tend to be muscle invasive and amplified in luminal subtype bladder cancers that tend to be non-muscle invasive. Bladder cancers derive from the urothelium, one of the most quiescent epithelia in the body, which is composed of basal, intermediate, and superficial cells. We find that expression of an activated form of Pparg (VP16;Pparg) in basal progenitors induces formation of superficial cells in situ, that exit the cell cycle, and do not form tumors. Expression in basal progenitors that have been activated by mild injury however, results in luminal tumor formation. We find that these tumors are immune deserted, which may be linked to down-regulation of Nf-kb, a Pparg target. Interestingly, some luminal tumors begin to shift to basal subtype tumors with time, down-regulating Pparg and other luminal markers. Our findings have important implications for treatment and diagnosis of bladder cancer.

PPARg is differentially expressed in bladder cancer subtypes. Here, the authors show in mice that when an activated form of PPARg is expressed in basal bladder cells tumours do not form, however in the presence of injury the basal cells differentiate into luminal cells.

NRF2 promotes urothelial cell response to bacterial infection by regulating reactive oxygen species and RAB27B expression

Uropathogenic Escherichia coli (UPEC) cause urinary tract infections (UTIs) by invading urothelial cells. In response, the host mounts an inflammatory response to expel bacteria. Here, we show that the NF-E2-related factor 2 (NRF2) pathway is activated in response to UPEC-triggered reactive oxygen species (ROS) production. We demonstrate the molecular sequence of events wherein NRF2 activation in urothelial cells reduces ROS production, inflammation, and cell death, promotes UPEC expulsion, and reduces the bacterial load. In contrast, loss of NRF2 leads to increased ROS production, bacterial burden, and inflammation, both in vitro and in vivo. NRF2 promotes UPEC expulsion by regulating transcription of the RAB-GTPase RAB27B. Finally, dimethyl fumarate, a US Food and Administration-approved NRF2 inducer, reduces the inflammatory response, increases RAB27B expression, and lowers bacterial burden in urothelial cells and in a mouse UTI model. Our findings elucidate mechanisms underlying the host response to UPEC and provide a potential strategy to combat UTIs.

Integrated Analysis of the Expression Characteristics, Prognostic Value, and Immune Characteristics of PPARG in Breast Cancer

Background: Breast cancer (BRCA) is the most frequent malignancy. Identification of potential biomarkers could help to better understand and combat the disease at early stages. Methods: We selected the overlapping genes of differential expressed genes and genes in BRCA-highly correlated modules by Weighted Gene Co-Expression Network Analysis (WGCNA) in TCGA and GEO data and performed KEGG and GO enrichment. PPARG was achieved from Protein-Protein Interaction (PPI) network analysis and prognostic analysis. TIMER, UALCAN, GEO, TCGA, and western blot analysis were used to validate the expression of PPARG in BRCA. PPARG was further analyzed by DNA methylation, immune parameters, and tumor mutation burden. Results: Among 381 overlapping genes, the lipid metabolic process was identified as highly enriched pathways in BRCA by TCGA and GEO data. When the prognostic analysis of 10 core genes by PPI network was performed, results revealed that high expression of PPARG was significantly correlated to a better prognosis. PPARG was lesser expression in BRCA according to TIMER, UALCAN, GEO, TCGA, and western blot in both mRNA level and protein level. PPARG had several high DNA methylation level sites and the methylation level is negatively correlated to expression. PPARG is also correlated to TNM stages, tumor microenvironment, and tumor burden. Conclusions: Findings of our study identified the PPARG as a potential biomarker by confirming its low expression in BRCA and its correlation to prognosis. Moreover, its correlation to DNA methylation and tumor microenvironment may guide new therapeutic strategies for BRCA patients.

Establishment of a novel CNV-related prognostic signature predicting prognosis in patients with breast cancer

BACKGROUND

Copy number variation (CNVs) is a key factor in breast cancer development. This study determined prognostic molecular characteristics to predict breast cancer through performing a comprehensive analysis of copy number and gene expression data.

METHODS

Breast cancer expression profiles, CNV and complete information from The Cancer Genome Atlas (TCGA) dataset were collected. Gene Expression Omnibus (GEO) chip data sets (GSE20685 and GSE31448) containing breast cancer samples were used as external validation sets. Univariate survival COX analysis, multivariate survival COX analysis, least absolute shrinkage and selection operator (LASSO), Chi square, Kaplan-Meier (KM) survival curve and receiver operating characteristic (ROC) analysis were applied to build a gene signature model and assess its performance.

RESULTS

A total of 649 CNV related-differentially expressed gene obtained from TCGA-breast cancer dataset were related to several cancer pathways and functions. A prognostic gene sets with 9 genes were developed to stratify patients into high-risk and low-risk groups, and its prognostic performance was verified in two independent patient cohorts (n = 327, 246). The result uncovered that 9-gene signature could independently predict breast cancer prognosis. Lower mutation of PIK3CA and higher mutation of TP53 and CDH1 were found in samples with high-risk score compared with samples with low-risk score. Patients in the high-risk group showed higher immune score, malignant clinical features than those in the low-risk group. The 9-gene signature developed in this study achieved a higher AUC.

CONCLUSION

The current research established a 5-CNV gene signature to evaluate prognosis of breast cancer patients, which may innovate clinical application of prognostic assessment.

Regulation of macrophage functions by FABP-mediated inflammatory and metabolic pathways

Macrophages are almost everywhere in the body, where they serve pivotal functions in maintaining tissue homeostasis, remodeling, and immunoregulation. Macrophages are traditionally thought to differentiate from bone marrow-derived hematopoietic stem cells (HSCs). Emerging studies suggest that some tissue macrophages at steady state originate from embryonic precursors in the yolk sac or fetal liver and are maintained in situ by self-renewal, but bone marrow-derived monocytes can give rise to tissue macrophages in pathogenic settings, such as inflammatory injuries and cancer. Macrophages are popularly classified as Th1 cytokine (e.g. IFNγ)-activated M1 macrophages (the classical activation) or Th2 cytokine (e.g. IL-4)-activated M2 macrophages (the alternative activation). However, given the myriad arrays of stimuli macrophages may encounter from local environment, macrophages exhibit notorious heterogeneity in their phenotypes and functions. Determining the underlying metabolic pathways engaged during macrophage activation is critical for understanding macrophage phenotypic and functional adaptivity under different disease settings. Fatty acid binding proteins (FABPs) represent a family of evolutionarily conserved proteins facilitating lipid transport, metabolism and responses inside cells. More specifically, adipose-FABP (A-FABP) and epidermal-FABP (E-FABP) are highly expressed in macrophages and play a central role in integrating metabolic and inflammatory pathways. In this review we highlight how A-FABP and E-FABP are respectively upregulated in different subsets of activated macrophages and provide a unique perspective in defining macrophage phenotypic and functional heterogeneity through FABP-regulated lipid metabolic and inflammatory pathways.

Transcriptional networks controlling stromal cell differentiation

Stromal progenitors are found in many different tissues, where they play an important role in the maintenance of tissue homeostasis owing to their ability to differentiate into parenchymal cells. These progenitor cells are differentially pre-programmed by their tissue microenvironment but, when cultured and stimulated in vitro, these cells - commonly referred to as mesenchymal stromal cells (MSCs) - exhibit a marked plasticity to differentiate into many different cell lineages. Loss-of-function studies in vitro and in vivo have uncovered the involvement of specific signalling pathways and key transcriptional regulators that work in a sequential and coordinated fashion to activate lineage-selective gene programmes. Recent advances in omics and single-cell technologies have made it possible to obtain system-wide insights into the gene regulatory networks that drive lineage determination and cell differentiation. These insights have important implications for the understanding of cell differentiation, the contribution of stromal cells to human disease and for the development of cell-based therapeutic applications.