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.

Cancer-associated Fibroblasts in Bladder Cancer: Origin, Biology, and Therapeutic Opportunities.

CONTEXT: Bladder cancer (BLCA) is a highly prevalent tumour and a health problem worldwide, especially among men. Recent work has highlighted the relevance of the tumour microenvironment (TME) in cancer biology with translational implications. Cancer-associated fibroblasts (CAFs) are a prominent, heterogeneous population of cells in the TME. CAFs have been associated with tumour development, progression, and poor prognosis in several neoplasms. However, their role in BLCA has not yet been exploited deeply. OBJECTIVE: To review the role of CAFs in BLCA biology and provide an understanding of CAF origin, subtypes, markers, and phenotypic and functional characteristics to improve patient management. EVIDENCE ACQUISITION: A PubMed search was performed to review manuscripts published using the terms "cancer associated fibroblast" and "bladder cancer" or "urothelial cancer". All abstracts were reviewed, and the full content of all relevant manuscripts was analysed. In addition, selected manuscripts on CAFs in other tumours were considered. EVIDENCE SYNTHESIS: CAFs have been studied less extensively in BLCA than in other tumours. Thanks to new techniques, such as single-cell RNA-seq and spatial transcriptomics, it is now possible to accurately map and molecularly define the phenotype of fibroblasts in normal bladder and BLCA. Bulk transcriptomic analyses have revealed the existence of subtypes among both non-muscle-invasive and muscle-invasive BLCA; these subtypes display distinct features regarding their CAF content. We provide a higher-resolution map of the phenotypic diversity of CAFs in these tumour subtypes. Preclinical studies and recent promising clinical trials leverage on this knowledge through the combined targeting of CAFs or their effectors and the immune microenvironment. CONCLUSIONS: Current knowledge of BLCA CAFs and the TME is being increasingly applied to improve BLCA therapy. There is a need to acquire a deeper understanding of CAF biology in BLCA. PATIENT SUMMARY: Tumour cells are surrounded by nontumoural cells that contribute to the determination of the behaviour of cancers. Among them are cancer-associated fibroblasts. The "neighbourhoods" established through these cellular interactions can now be studied with much greater resolution. Understanding these features of tumours will contribute to the designing of more effective therapies, especially in relationship to bladder cancer immunotherapy.

Tumor and Stromal Cell Targeting with Nintedanib and Alpelisib Overcomes Intrinsic Bladder Cancer Resistance.

Bladder cancer is a highly prevalent tumor, requiring the urgent development of novel therapies, especially for locally advanced and metastatic disease. Nintedanib is a potent antifibrotic angio-kinase inhibitor, which has shown clinical efficacy in combination with chemotherapy in patients with locally advanced muscle-invasive bladder cancer. Nintedanib inhibits fibroblast growth factor receptors (FGFRs), validated targets in patients with bladder cancer harboring FGFR3/2 genetic alterations. Here, we aimed at studying its mechanisms of action to understand therapy resistance, identify markers predictive of response, and improve the design of future clinical trials. We have used a panel of genetically well-characterized human bladder cancer cells to identify the molecular and transcriptomic changes induced upon treatment with nintedanib, in vitro and in vivo, at the tumor and stroma cell levels. We showed that bladder cancer cells display an intrinsic resistance to nintedanib treatment in vitro, independently of their FGFR3 status. However, nintedanib has higher antitumor activity on mouse xenografts. We have identified PI3K activation as a resistance mechanism against nintedanib in bladder cancer and evidenced that the combination of nintedanib with the PI3K inhibitor alpelisib has synergistic antitumor activity. Treatment with this combination is associated with cell-cycle inhibition at the tumoral and stromal levels and potent nontumor cell autonomous effects on α-smooth muscle actin-positive tumor infiltrating cells and tumor vasculature. The combination of nintedanib with PI3K inhibitors not only reversed bladder cancer resistance to nintedanib but also enhanced its antiangiogenic effects.

Febrile young infants with abnormal urine dipstick at low risk of invasive bacterial infection.

OBJECTIVES: To develop and validate a prediction rule to identify well-appearing febrile infants aged ≤90 days with an abnormal urine dipstick at low risk of invasive bacterial infections (IBIs, bacteraemia or bacterial meningitis). DESIGN: Ambispective, multicentre study. SETTING: The derivation set in a single paediatric emergency department (ED) between 2003 and 2017. The validation set in 21 European EDs between December 2017 and November 2019. PATIENTS: Two sets of well-appearing febrile infants aged ≤90 days with an abnormal urine dipstick (either leucocyte esterase and/or nitrite positive test). MAIN OUTCOME: Prevalence of IBI in low-risk infants according to the RISeuP score. RESULTS: We included 662 infants in the derivation set (IBI rate:5.2%). After logistic regression, we developed a score (RISeuP score) including age (≤15 days old), serum procalcitonin (≥0.6 ng/mL) and C reactive protein (≥20 mg/L) as risk factors. The absence of any risk factor had a sensitivity of 96.0% (95% CI 80.5% to 99.3%), a negative predictive value of 99.4% (95% CI 96.4% to 99.9%) and a specificity of 32.9% (95% CI 28.8% to 37.3%) for ruling out an IBI. Applying it in the 449 infants of the validation set (IBI rate 4.9%), sensitivity, negative predictive value and specificity were 100% (95% CI 87.1% to 100%), 100% (95% CI 97.3% to 100%) and 29.7% (95% CI 25.8% to 33.8%), respectively. CONCLUSION: This prediction rule accurately identified well-appearing febrile infants aged ≤90 days with an abnormal urine dipstick at low risk of IBI. This score can be used to guide initial clinical decision-making in these patients, selecting infants suitable for an outpatient management.

Dolores referidos como causa de errores / Errors and referred pain

Introducción. El dolor es el síntoma más frecuente que permite etectar problemas de salud; sin embargo, cuando el dolor no es localizado, sino referido o irradiado, puede dificultar el diagnóstico e inducir a error. Se describen tres casos con dolor como motivo de consulta y en los que hay una orientación inicial errónea al ser éste referido. Observación clínica. El primer caso es un niño de 9 años, con antecedente de caída en bicicleta 18 horas antes, que solicita valoración traumatológica al presentar dolor en el hombro izquierdo y en abdomen. El segundo caso es un niño de 4 años que es remitido por dolor en el brazo izquierdo que aparece en el contexto de un cuadro respiratorio febril. En el tercer caso, un joven de 16 años presenta dolor en fosa iliaca derecha de inicio súbito, por lo que se solicita valoración por cirugía. Los diagnósticos finales fueron laceración del bazo, neumonía y torsión del conducto espermático, respectivamente. Comentarios. El dolor, cuando es localizado, orienta claramente a la zona afectada y facilita la orientación diagnóstica. Por contra, cuando es referido, como en los tres casos descritos, o irradiado, puede ser motivo de confusión. Por ello, el conocimiento de la fisiología y semiología del dolor, así como la realización de una exploración física reglada, evitaran posibles errores diagnósticos(AU)

Introduction. Pain is the most common symptom to lead to the detection of health problems; however, when it is referred or irradiated, rather than localized, it can make the diagnosis difficult and induce to diagnostic errors. Herein we describe three cases of children who presented with referred pain that resulted in the wrong initial diagnosis. Clinical Observation. The first case was a 9-year-old boy who presented with a history of bicycle accident 18 hours earlier; trauma evaluation was requested due to left shoulder and abdominal pain. The second case was a 4-year-old boy who was referred due to left arm pain in the context of a febrile respiratory illness. The third case was a 16-year-old adolescent male with sudden onset of right lower quadrant pain that led to evaluation by surgery. The final diagnoses were splenic laceration, pneumonia, and testicular torsion, respectively. Comments. Well-localized pain points towards the affected areas and it is useful in the differential diagnosis. However, referred pain, as in the three cases described, may lead to confusion. Therefore, becoming familiar with the semiology and physiology of pain, and performing a comprehensive physical examination, can avoid misdiagnosis(AU)

Púrpura de Schölein-Henoch:Estudio retrospectivo de los últimos 20 años / Henoch-Schonlein purpura: a 20-year retrospective study

Fundamento. La púrpura de Schónlein-Henoch (PSH) es una vasculitis sistémica por hipersensibilidad, mediada por Ig-A, que afecta casi exclusivamente a la edad pediátrica. Las afectaciones principales son a nivel cutáneo, gastrointestinal, renal y articular. La afectación nefrológica, que se puede presentar desde su inicio o bien días o semanas después, condiciona el pronóstico. Objetivo. Evaluar las características clínicas, epidemiológicas y evolutivas de la enfermedad de los niños con diagnóstico de PSH controlados en consultas externas de nefrología pediátrica. Método. Estudio retrospectivo y descriptivo realizado entre septiembre de 1980 i enero de 2001. Se han revisado las historias clínicas de los pacientes controlados en consulta externa por presentar una PSH. Resultado. Hemos estudiado 77 pacientes con una edad media de 4.7 años (2 -15 años). Encontramos antecedentes de infección aguda en 17 (22 por ciento) de los que 6 son amigdalitis. Todos han presentado afectación cutánea no siendo la forma de debut en dos (1 dolor abdominal, 1 artritis). Encontramos dolor abdominal en 22 (28.5 por ciento), 2 acompañados de hemorragia digestiva i 1 de invaginación que requirió intervención. La afectación articular se observa en 22 (28.5 por ciento). Hemos encontrado afectación renal en 17 (22 por ciento). De éstos, 3 han tenido síndrome nefrótico y a 2 se le ha realizado biopsia renal (2 nefropaties IgA con glomerulonefritis segmentaria y focal y 1 de éstos con 20 por ciento de semilunas). Han presentado rebrote 21 (29 por ciento). Han recibido tratamiento con corticoides 8 (11.2 por ciento). Conclusiones. 1. La afectación renal encontrada es similar a otras series publicadas (20-25 por ciento). 2. La posibilidad de una afectación renal, que ocasionalmente puede ser grave, obliga al seguimiento de los pacientes con PSH. 3. La determinación por tira reactiva de orina de proteinuria y/o hematuria es un buen instrumento para el cribado. (AU)