Background: Defective barrier function is a predisposing factor in inflammatory bowel disease (IBD) and colitis-associated cancer (CAC). While TGFβ signaling defects have been associated with IBD and CAC, few studies have examined the relationship between TGFβ and intestinal barrier function. Here, we examine the role of TGFβ signaling via SMAD4 in modulation of colon barrier function. Methods: The Smad4 gene was conditionally deleted in the intestines of adult mice and intestinal permeability assessed using an in vivo 4kD FITC-Dextran (FD4) permeability assay. Mouse colon was isolated for gene expression (RNA-sequencing), western blot, and immunofluorescence analysis. In vitro colon organoid culture was utilized to assess junction-related gene expression by qPCR and trans-epithelial resistance (TER). In silico analyses of human IBD and colon cancer databases were performed. Results: Mice lacking intestinal expression of Smad4 demonstrate increased colonic permeability to FD4 without gross mucosal damage. mRNA/protein expression analyses demonstrate significant increases in Cldn2/Claudin 2 and Cldn8/Claudin 8, and decreases in Cldn3, Cldn4, and Cldn7/Claudin 7 with intestinal SMAD4 loss in vivo without changes in Claudin protein localization. TGFb1/BMP2 treatment of polarized SMAD4+ colonoids increases TER. Cldn2, Cldn4, Cldn7, and Cldn8 are regulated by canonical TGFβ signaling, and TGFβ-dependent regulation of these genes is dependent on nascent RNA transcription (Cldn2, Cldn4, Cldn8) but not nascent protein translation (Cldn4, Cldn8). Human IBD/colon cancer specimens demonstrate decreased SMAD4, CLDN4, CLDN7, and CLDN8 and increased CLDN2 compared to healthy controls. Conclusion: Canonical TGFβ signaling modulates the expression of tight junction proteins and barrier function in mouse colon.

BACKGROUND: The effects of blood transfusions on oncologic outcomes after surgery remain inconclusive. Thus, we examined the association between receiving a perioperative blood transfusion and oncologic outcomes in patients undergoing curative rectal cancer resection. OBJECTIVE: The purpose of this study was to assess the association between receiving a perioperative blood transfusion with disease-free and overall survival in patients undergoing curative resection of clinical stage I to III rectal cancer. We hypothesized that blood transfusion is associated with worse disease-free and overall survival in this patient cohort. DESIGN: This was a retrospective cohort study using a propensity score–matched analysis. SETTINGS: The study involved 6 tertiary academic medical centers in the United States contributing to the United States Rectal Cancer Consortium. PATIENTS: Patients who underwent curative resection for rectal cancer from 2010 to 2018 were included. MAIN OUTCOME MEASURES: The primary outcome was disease-free survival. The secondary outcomes were overall survival, intensive care unit length of stay, hospital length of stay, surgical site infection, and readmission. RESULTS: Of the 924 patients eligible for matching, 312 patients were matched, including 100 patients who received a transfusion and 212 who did not. In a propensity score–matched analysis, receiving a perioperative blood transfusion was not associated with worse 5-year disease-free survival (transfused, 78%; not transfused, 83%; p = 0.32) but was associated with worse 5-year overall survival (transfused 65% vs not transfused 86%; p < 0.001) and increased hospital length of stay (transfused, 9.9 d; not transfused, 7.6 d; p = 0.001). LIMITATIONS: Despite propensity matching, confounding may remain. Propensity matching may limit the power to detect a difference in disease-free survival. CONCLUSIONS: Receiving a perioperative blood transfusion is not associated with worse disease-free survival but is associated with worse overall survival. Such findings are important for clinicians and patients to understand when considering perioperative blood transfusions. See Video Abstract at http://links.lww.com/DCR/B531. LAS TRANSFUSIONES DE SANGRE PERIOPERATORIAS SE ASOCIAN CON UNA PEOR SOBREVIDA GLOBAL, PERO NO CON LA SOBREVIDA LIBRE DE ENFERMEDAD POSTERIOR A LA RESECCIÓN CURATIVA DEL CÁNCER DE RECTO: UN PUNTAJE DE PROPENSIÓN POR ANÁLISIS DE CONCORDANCIA ANTECEDENTES: El impacto de las transfusiones de sangre en los resultados oncológicos posteriores a la cirugía no son concluyentes. Por lo anterior, estudiamos la asociación entre recibir una transfusión de sangre perioperatoria y los resultados oncológicos en pacientes llevados a resección curativa de cáncer de recto. OBJETIVO: El propósito de este estudio fue evaluar la asociación entre recibir una transfusión de sangre perioperatoria con la sobrevida libre de enfermedad y la sobrevida general en pacientes llevados a resección curativa de cáncer de recto en estadio clínico I-III. Nuestra hipótesis es que la transfusión de sangre se asocia con una peor sobrevida global y libre de enfermedad en esta cohorte de pacientes. DISEÑO: Es un estudio de cohorte retrospectivo que utilizó un puntaje de propensión por análisis de concordancia. AMBITO: El estudio se realizó en seis centros médicos académicos de tercer nivel en los Estados Unidos que contribuían al Consorcio de Cáncer de Recto de los Estados Unidos. PACIENTES: Se incluyeron pacientes que fueron llevados a resección curativa por cáncer de recto entre 2010 y 2018. PRINCIPALES VARIABLES EVALUADAS: El objeitvo principal fue la sobrevida libre de enfermedad. Los objetivos secundarios fueron la sobrevida global, el tiempo de estancia en la unidad de cuidados intensivos, el tiempo de la estancia hospitalaria, la infección del sitio quirúrgico y el reingreso. RESULTADOS: De los 924 pacientes elegibles para el emparejamiento, se emparejaron 312 pacientes, incluidos 100 pacientes que recibieron una transfusión y 212 que no. En el puntaje de propensión por análisis de concordancia, recibir una transfusión de sangre perioperatoria no se asoció con una peor sobrevida libre de enfermedad a 5 años (TRANSFUSIÓN 78%; NO TRANSFUSIÓN 83%; p = 0,32), pero se asoció con una peor sobrevida global a 5 años (TRANSFUSION 65% vs NO TRANSFUSION 86%; p <0,001) y aumento de la estancia hospitalaria (TRANSFUSIÓN 9,9 días; NO TRANSFUSION 7,6 días; p = 0,001). LIMITACIONES: A pesar de la concordancia de propensión, pueden existir desviaciones. El emparejamiento de propensión puede limitar el poder para detectar una diferencia en la sobrevida libre de enfermedad. CONCLUSIONES: Recibir una transfusión de sangre perioperatoria no se asocia con una peor sobrevida libre de enfermedad, pero sí con una peor sobrevida global. Es importante que los médicos y los pacientes comprendan estos hallazgos al considerar las transfusiones de sangre perioperatorias. Consulte Video Resumen en http://links.lww.com/DCR/B531. (Traducción—Dr Lisbeth Alarcon-Bernes)

Papillary thyroid carcinoma (PTC) demonstrates significantly reduced patient survival with metastatic progression. Tumor progression can be influenced by metabolism, including antioxidant glutathione (GSH). Glutathione peroxidase 4 (GPX4) is a selenoenzyme that uses GSH as a co-factor to regulate lipid peroxidation of cell membranes during increased oxidative stress. GPX4 suppression in tumor cells can induce ferroptosis. This study aims to examine ferroptosis as a potentially critical pathway in effective targeting of thyroid cancer (TC) cells. We treated human TC cells (K1, MDA-T68, MDA-T32, TPC1) with (1S,3R)-RSL3 (RSL3), a small-molecule inhibitor of GPX4 and examined the effects on ferroptosis, tumor cell survival and migration, spheroid formation, oxidative stress, DNA damage repair response, and mTOR signaling pathway in vitro. GPX4 inhibition activated ferroptosis, inducing TC cell death, rapid rise in reactive oxygen species and effectively arrested cell migration in vitro. Suppression of mTOR signaling pathway triggered autophagy. GPX4 genetic knockdown mirrored RSL3 effect on mTOR pathway suppression. RSL3 subdued DNA damage repair response by suppressing phosphorylation of nucleophosmin 1 (NPM1). Thus, observed potent induction of ferroptosis, GPX4-dependent novel suppression of mTOR pathway and DNA damage repair response in preclinical in vitro model of TC supports GPX4 targeting for therapeutic benefit in advanced therapy-resistant thyroid cancers.

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IMPORTANCEThe clinical significance of gangrenous, suppurative, or exudative (GSE) findings is poorly characterized in children with nonperforated appendicitis. OBJECTIVE To evaluate whether GSE findings in children with nonperforated appendicitis are associated with increased risk of surgical site infections and resource utilization. DESIGN, SETTING, AND PARTICIPANTSThis multicenter cohort study used data from the Appendectomy Targeted Database of the American College of Surgeons Pediatric National Surgical Quality Improvement Program, which were augmented with operative report data obtained by supplemental medical record review. Data were obtained from 15 hospitals participating in the Eastern Pediatric Surgery Network (EPSN) research consortium. The study cohort comprised children (aged Յ18 years) with nonperforated appendicitis who underwent appendectomy from July 1, 2015, to June 30, 2020.EXPOSURES The presence of GSE findings was established through standardized, keyword-based audits of operative reports by EPSN surgeons. Interrater agreement for the presence or absence of GSE findings was evaluated in a random sample of 900 operative reports. MAIN OUTCOMES AND MEASURESThe primary outcome was 30-day postoperative surgical site infections (incisional and organ space infections). Secondary outcomes included rates of hospital revisits, postoperative abdominal imaging, and postoperative length of stay. Multivariable mixed-effects regression was used to adjust measures of association for patient characteristics and clustering within hospitals. RESULTS Among 6133 children with nonperforated appendicitis, 867 (14.1%) had GSE findings identified from operative report review (hospital range, 4.2%-30.2%; P < .001). Reviewers agreed on presence or absence of GSE findings in 93.3% of cases (weighted κ, 0.89; 95% CI, 0.86-0.92). In multivariable analysis, GSE findings were associated with increased odds of any surgical site infection (4.3% vs 2.2%; odds ratio [OR], 1.91; 95% CI, 1.35-2.71; P < .001), organ space infection (2.8% vs 1.1%; OR, 2.18; 95% CI, 1.30-3.67; P = .003), postoperative imaging (5.8% vs 3.7%; OR, 1.70; 95% CI, 1.23-2.36; P = .002), and prolonged mean postoperative length of stay (1.6 vs 0.9 days; rate ratio, 1.43; 95% CI, 1.32-1.54; P < .001). CONCLUSIONS AND RELEVANCEIn children with nonperforated appendicitis, findings of gangrene, suppuration, or exudate are associated with increased surgical site infections and resource utilization. Further investigation is needed to establish the role and duration of postoperative antibiotics and inpatient management to optimize outcomes in this cohort of children.