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1.
Heliyon ; 10(13): e33838, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39027559

RESUMEN

Hypusine is an amino acid synthesized by the enzyme deoxyhypusine synthase (DHPS). It is critical for the activity of eukaryotic translation initiation factor 5A (EIF5A). We reported that hypusination i) in macrophages supports the innate response towards pathogenic bacteria and ii) in epithelial cells maintains intestinal homeostasis. Herein, we investigated the effect of myeloid hypusination on the outcome of colitis and colitis-associated cancer. We found that patients with Crohn's disease exhibit increased levels of DHPS and EIF5AHyp in cells infiltrating the colon lamina propria. However, the specific deletion of Dhps in myeloid cells had no impact on clinical, histological, or inflammatory parameters in mice treated with dextran sulfate sodium (DSS). Further, tumorigenesis and level of dysplasia were not affected by myeloid deletion of Dhps in the azoxymethane-DSS model. The composition of the fecal and the mucosa-associated microbiome was similar in animals lacking or not DHPS in myeloid cells. Thus, hypusination in myeloid cells does not regulate colitis associated with epithelial injury and colitis-associated cancer. Enhancement of the DHPS/hypusine pathway in patients with inflammatory bowel disease could have therapeutic impact through epithelial effects, but modulation of hypusination in myeloid cells will be unlikely to affect the disease.

2.
bioRxiv ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38798529

RESUMEN

Clostridioides difficile is a common cause of diarrhea and mortality, especially in immunosuppressed and hospitalized patients. C. difficile is a toxin-mediated disease, but the host cell receptors for C. difficile toxin B (TcdB) have only recently been revealed. Emerging data suggest TcdB interacts with receptor tyrosine kinases during infection. In particular, TcdB can elicit Epidermal Growth Factor Receptor (EGFR) transactivation in human colonic epithelial cells. The mechanisms for this function are not well understood, and the involvement of other receptors in the EGFR family of Erythroblastic Leukemia Viral Oncogene Homolog (ErbB) receptors remains unclear. Furthermore, in an siRNA-knockdown screen for protective genes involved with TcdB toxin pathogenesis, we show ErbB2 and ErbB3 loss resulted in increased cell viability. We hypothesize TcdB induces the transactivation of EGFR and/or ErbB receptors as a component of its cell-killing mechanism. Here, we show in vivo intrarectal instillation of TcdB in mice leads to phosphorylation of ErbB2 and ErbB3. However, immunohistochemical staining for phosphorylated ErbB2 and ErbB3 indicated no discernible difference between control and TcdB-treated mice for epithelial phospho-ErbB2 and phospho-ErbB3. Human colon cancer cell lines (HT29, Caco-2) exposed to TcdB were not protected by pre-treatment with lapatinib, an EGFR/ErbB2 inhibitor. Similarly, lapatinib pre-treatment failed to protect normal human colonoids from TcdB-induced cell death. Neutralizing antibodies against mouse EGFR failed to protect mice from TcdB intrarectal instillation as measured by edema, inflammatory infiltration, and epithelial injury. Our findings suggest TcdB-induced colonocyte cell death does not require EGFR/ErbB receptor tyrosine kinase activation.

3.
mBio ; 15(4): e0029824, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38441000

RESUMEN

Observational evidence suggests that human milk oligosaccharides (HMOs) promote the growth of commensal bacteria in early life and adulthood. However, the mechanisms by which HMOs benefit health through modulation of gut microbial homeostasis remain largely unknown. 2'-fucosyllactose (2'-FL) is the most abundant oligosaccharide in human milk and contributes to the essential health benefits associated with human milk consumption. Here, we investigated how 2'-FL prevents colitis in adulthood through its effects on the gut microbial community. We found that the gut microbiota from adult mice that consumed 2'-FL exhibited an increase in abundance of several health-associated genera, including Bifidobacterium and Lactobacillus. The 2'-FL-modulated gut microbial community exerted preventive effects on colitis in adult mice. By using Bifidobacterium infantis as a 2'-FL-consuming bacterial model, exploratory metabolomics revealed novel 2'-FL-enriched secretory metabolites by Bifidobacterium infantis, including pantothenol. Importantly, pantothenate significantly protected the intestinal barrier against oxidative stress and mitigated colitis in adult mice. Furthermore, microbial metabolic pathway analysis identified 26 dysregulated metabolic pathways in fecal microbiota from patients with ulcerative colitis, which were significantly regulated by 2'-FL treatment in adult mice, indicating that 2'-FL has the potential to rectify dysregulated microbial metabolism in colitis. These findings support the contribution of the 2'-FL-shaped gut microbial community and bacterial metabolite production to the protection of intestinal integrity and prevention of intestinal inflammation in adulthood.IMPORTANCEAt present, neither basic research nor clinical studies have revealed the exact biological functions or mechanisms of action of individual oligosaccharides during development or in adulthood. Thus, it remains largely unknown whether human milk oligosaccharides could serve as effective therapeutics for gastrointestinal-related diseases. Results from the present study uncover 2'-FL-driven alterations in bacterial metabolism and identify novel B. infantis-secreted metabolites following the consumption of 2'-FL, including pantothenol. This work further demonstrates a previously unrecognized role of pantothenate in significantly protecting the intestinal barrier against oxidative stress and mitigating colitis in adult mice. Remarkably, 2'-FL-enhanced bacterial metabolic pathways are found to be dysregulated in the fecal microbiota of ulcerative colitis patients. These novel metabolic pathways underlying the bioactivities of 2'-FL may lay a foundation for applying individual oligosaccharides for prophylactic intervention for diseases associated with impaired intestinal homeostasis.


Asunto(s)
Colitis Ulcerosa , Colitis , Microbioma Gastrointestinal , Ácido Pantoténico/análogos & derivados , Adulto , Humanos , Animales , Ratones , Leche Humana , Colitis Ulcerosa/metabolismo , Oligosacáridos/metabolismo , Colitis/prevención & control , Inflamación
5.
Infect Immun ; 92(1): e0029223, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38014948

RESUMEN

Activation of Th17 cell responses, including the production of IL-17A and IL-21, contributes to host defense and inflammatory responses by coordinating adaptive and innate immune responses. IL-17A and IL-17F signal through a multimeric receptor, which includes the IL-17 receptor A (IL-17RA) subunit and the IL-17RC subunit. IL-17RA is expressed by many cell types, and data from previous studies suggest that loss of IL-17 receptor is required to limit immunopathology in the Helicobacter pylori model of infection. Here, an Il17ra-/- mouse was generated on the FVB/n background, and the role of IL-17 signaling in the maintenance of barrier responses to H. pylori was investigated. Generating the Il17ra-/- on the FVB/n background allowed for the examination of responses in the paragastric lymph node and will allow for future investigation into carcinogenesis. While uninfected Il17ra-/- mice do not develop spontaneous gastritis following H. pylori infection, Il17ra-/- mice develop severe gastric inflammation accompanied by lymphoid follicle production and exacerbated production of Th17 cytokines. Increased inflammation in the tissue, increased IgA levels in the lumen, and reduced production of Muc5ac in the corpus correlate with increased H. pylori-induced paragastric lymph node activation. These data suggest that the cross talk between immune cells and epithelial cells regulates mucin production, IgA production, and translocation, impacting the integrity of the gastric mucosa and therefore activating of the adaptive immune response.


Asunto(s)
Gastritis , Infecciones por Helicobacter , Helicobacter pylori , Ratones , Animales , Interleucina-17/genética , Interleucina-17/metabolismo , Helicobacter pylori/fisiología , Receptores de Interleucina-17/genética , Receptores de Interleucina-17/metabolismo , Mucosa Gástrica/metabolismo , Inflamación/metabolismo , Inmunoglobulina A/metabolismo
6.
J Allergy Clin Immunol ; 153(3): 759-771, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37852329

RESUMEN

BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic immune mediated inflammatory disorder of the esophagus. It is still unknown why children and adults present differently, and there is little evidence about why it is more common in men than women. OBJECTIVE: Our aim was to synthesize published and unpublished esophageal bulk RNA-sequencing (RNA-seq) data to gain novel insights into the pathobiology of EoE and examine the differences in EoE transcriptome by sex and age group. METHODS: Esophageal bulk RNA-seq data from 5 published and 2 unpublished studies resulting in 137 subjects (EoE: N = 76; controls: N = 61) were analyzed. For overall analysis, combined RNA-seq data of patients with EoE were compared with those of controls and subgroup analysis was conducted in patients with EoE by age of the patient (children [<18 years] vs adults [≥18 years]) and sex (female vs male). Gene-set enrichment analysis, ingenuity pathway analysis (IPA), cell-type analysis, immunohistochemistry, and T-cell or B-cell receptor analysis were performed. RESULTS: Overall analysis identified dysregulation of new genes in EoE compared with controls. IPA revealed that EoE is characterized by a mixed inflammatory response compared with controls. Cell-type analysis showed that cell composition varied with age: children had more mast cells, whereas adults had more macrophages. Finally, gene-set enrichment analysis and IPA revealed pathways that were differentially regulated in adults versus children and male versus female patients with EoE. CONCLUSIONS: Using a unique approach to analyze bulk RNA-seq data, we found that EoE is characterized by a mixed inflammatory response, and the EoE transcriptome may be influenced by age and sex. These findings enhance insights into the molecular mechanisms of EoE.


Asunto(s)
Esofagitis Eosinofílica , Niño , Adulto , Humanos , Masculino , Femenino , Adolescente , Esofagitis Eosinofílica/genética , Transcriptoma , Inmunohistoquímica , ARN
8.
Cancer ; 130(9): 1702-1710, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38140735

RESUMEN

INTRODUCTION: The American Joint Committee on Cancer (AJCC) staging system undergoes periodic revisions to maintain contemporary survival outcomes related to stage. Recently, the AJCC has developed a novel, systematic approach incorporating survival data to refine stage groupings. The objective of this study was to demonstrate data-driven optimization of the version 9 AJCC staging system for anal cancer assessed through a defined validation approach. METHODS: The National Cancer Database was queried for patients diagnosed with anal cancer in 2012 through 2017. Kaplan-Meier methods analyzed 5-year survival by individual clinical T category, N category, M category, and overall stage. Cox proportional hazards models validated overall survival of the revised TNM stage groupings. RESULTS: Overall, 24,328 cases of anal cancer were included. Evaluation of the 8th edition AJCC stage groups demonstrated a lack of hierarchical prognostic order. Survival at 5 years for stage I was 84.4%, 77.4% for stage IIA, and 63.7% for stage IIB; however, stage IIIA disease demonstrated a 73.0% survival, followed by 58.4% for stage IIIB, 59.9% for stage IIIC, and 22.5% for stage IV (p <.001). Thus, stage IIB was redefined as T1-2N1M0, whereas Stage IIIA was redefined as T3N0-1M0. Reevaluation of 5-year survival based on data-informed stage groupings now demonstrates hierarchical prognostic order and validated via Cox proportional hazards models. CONCLUSION: The 8th edition AJCC survival data demonstrated a lack of hierarchical prognostic order and informed revised stage groupings in the version 9 AJCC staging system for anal cancer. Thus, a validated data-driven optimization approach can be implemented for staging revisions across all disease sites moving forward.


Asunto(s)
Neoplasias del Ano , Humanos , Estados Unidos/epidemiología , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales
9.
Cell ; 186(25): 5620-5637.e16, 2023 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-38065082

RESUMEN

Colorectal cancer exhibits dynamic cellular and genetic heterogeneity during progression from precursor lesions toward malignancy. Analysis of spatial multi-omic data from 31 human colorectal specimens enabled phylogeographic mapping of tumor evolution that revealed individualized progression trajectories and accompanying microenvironmental and clonal alterations. Phylogeographic mapping ordered genetic events, classified tumors by their evolutionary dynamics, and placed clonal regions along global pseudotemporal progression trajectories encompassing the chromosomal instability (CIN+) and hypermutated (HM) pathways. Integrated single-cell and spatial transcriptomic data revealed recurring epithelial programs and infiltrating immune states along progression pseudotime. We discovered an immune exclusion signature (IEX), consisting of extracellular matrix regulators DDR1, TGFBI, PAK4, and DPEP1, that charts with CIN+ tumor progression, is associated with reduced cytotoxic cell infiltration, and shows prognostic value in independent cohorts. This spatial multi-omic atlas provides insights into colorectal tumor-microenvironment co-evolution, serving as a resource for stratification and targeted treatments.


Asunto(s)
Neoplasias Colorrectales , Inestabilidad de Microsatélites , Microambiente Tumoral , Humanos , Inestabilidad Cromosómica/genética , Neoplasias Colorrectales/patología , Perfilación de la Expresión Génica , Quinasas p21 Activadas/genética , Filogenia , Mutación , Progresión de la Enfermedad , Pronóstico
10.
Sci Rep ; 13(1): 22368, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102166

RESUMEN

The intestinal immune response is crucial in maintaining a healthy gut, but the enhanced migration of macrophages in response to pathogens is a major contributor to disease pathogenesis. Integrins are ubiquitously expressed cellular receptors that are highly involved in immune cell adhesion to endothelial cells while in the circulation and help facilitate extravasation into tissues. Here we show that specific deletion of the Tln1 gene encoding the protein talin-1, an integrin-activating scaffold protein, from cells of the myeloid lineage using the Lyz2-cre driver mouse reduces epithelial damage, attenuates colitis, downregulates the expression of macrophage markers, decreases the number of differentiated colonic mucosal macrophages, and diminishes the presence of CD68-positive cells in the colonic mucosa of mice infected with the enteric pathogen Citrobacter rodentium. Bone marrow-derived macrophages lacking expression of Tln1 did not exhibit a cell-autonomous phenotype; there was no impaired proinflammatory gene expression, nitric oxide production, phagocytic ability, or surface expression of CD11b, CD86, or major histocompatibility complex II in response to C. rodentium. Thus, we demonstrate that talin-1 plays a role in the manifestation of infectious colitis by increasing mucosal macrophages, with an effect that is independent of macrophage activation.


Asunto(s)
Colitis , Infecciones por Enterobacteriaceae , Animales , Ratones , Citrobacter rodentium , Colitis/genética , Colitis/prevención & control , Colon/patología , Células Endoteliales/metabolismo , Infecciones por Enterobacteriaceae/metabolismo , Inflamación/patología , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Talina/genética , Talina/metabolismo
11.
bioRxiv ; 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37873404

RESUMEN

Crohn's disease (CD) is a complex chronic inflammatory disorder that may affect any part of gastrointestinal tract with extra-intestinal manifestations and associated immune dysregulation. To characterize heterogeneity in CD, we profiled single-cell transcriptomics of 170 samples from 65 CD patients and 18 non-inflammatory bowel disease (IBD) controls in both the terminal ileum (TI) and ascending colon (AC). Analysis of 202,359 cells identified a novel epithelial cell type in both TI and AC, featuring high expression of LCN2, NOS2, and DUOX2, and thus is named LND. LND cells, confirmed by high-resolution in-situ RNA imaging, were rarely found in non-IBD controls, but expanded significantly in active CD. Compared to other epithelial cells, genes defining LND cells were enriched in antimicrobial response and immunoregulation. Moreover, multiplexed protein imaging demonstrated that LND cell abundance was associated with immune infiltration. Cross-talk between LND and immune cells was explored by ligand-receptor interactions and further evidenced by their spatial colocalization. LND cells showed significant enrichment of expression specificity of IBD/CD susceptibility genes, revealing its role in immunopathogenesis of CD. Investigating lineage relationships of epithelial cells detected two LND cell subpopulations with different origins and developmental potential, early and late LND. The ratio of the late to early LND cells was related to anti-TNF response. These findings emphasize the pathogenic role of the specialized LND cell type in both Crohn's ileitis and Crohn's colitis and identify novel biomarkers associated with disease activity and treatment response.

12.
Gut Microbes ; 15(2): 2264456, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37815528

RESUMEN

Several probiotic-derived factors have been identified as effectors of probiotics for exerting beneficial effects on the host. However, there is a paucity of studies to elucidate mechanisms of their functions. p40, a secretory protein, is originally isolated from a probiotic bacterium, Lactobacillus rhamnosus GG. Thus, this study aimed to apply structure-functional analysis to define the functional peptide of p40 that modulates the epigenetic program in intestinal epithelial cells for sustained prevention of colitis. In silico analysis revealed that p40 is composed of a signal peptide (1-28 residues) followed by a coiled-coil domain with uncharacterized function on the N-terminus, a linker region, and a ß-sheet domain with high homology to CHAP on the C-terminus. Based on the p40 three-dimensional structure model, two recombinant p40 peptides were generated, p40N120 (28-120 residues) and p40N180 (28-180 residues) that contain first two and first three coiled coils, respectively. Compared to full-length p40 (p40F) and p40N180, p40N120 showed similar or higher effects on up-regulating expression of Setd1b (encoding a methyltransferase), promoting mono- and trimethylation of histone 3 on lysine 4 (H3K4me1/3), and enhancing Tgfb gene expression and protein production that leads to SMAD2 phosphorylation in human colonoids and a mouse colonic epithelial cell line. Furthermore, supplementation with p40F and p40N120 in early life increased H3K4me1, Tgfb expression and differentiation of regulatory T cells (Tregs) in the colon, and mitigated disruption of epithelial barrier and inflammation induced by DSS in adult mice. This study reveals the structural feature of p40 and identifies a functional peptide of p40 that could maintain intestinal homeostasis.


Asunto(s)
Colitis , Microbioma Gastrointestinal , Probióticos , Adulto , Humanos , Animales , Ratones , Proteínas Bacterianas/genética , Péptidos , Colitis/prevención & control , Probióticos/farmacología
13.
iScience ; 26(10): 107829, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37736049

RESUMEN

Colonic epithelial repair is a key determinant of health. Repair involves changes in epithelial differentiation, an extensive proliferative response, and upregulation of regeneration-associated "fetal-like" transcripts, including Ly6a (Sca-1), that represent Yap1 and interferon targets. However, little is known about how this regenerative program terminates and how homeostasis is restored during injury and inflammation. Here we show that, after the initial entry into the regenerative state, the subsequent upregulation of tumor necrosis factor (TNF) receptor 2 (R2, TNFR2, Tnfrsf1b) clears the regenerative signaling and restores homeostatic patterns of epithelial differentiation. Targeted deletion of epithelial TNFR2 in vivo and in colonoid cultures revealed persistent expression of Ly6a, hyperproliferation, and reduced secretory differentiation. Moreover, mice lacking epithelial TNFR2 also failed to complete colon ulcer healing, suggesting that partial resolution of regenerative signaling is essential for the completion of the repair process. These results demonstrate how epithelial cells dynamically leverage a colitis-associated cytokine to choreograph repair.

14.
Cell Mol Gastroenterol Hepatol ; 16(6): 961-983, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37574015

RESUMEN

BACKGROUND AND AIMS: Eosinophils are present in several solid tumors and have context-dependent function. Our aim is to define the contribution of eosinophils in esophageal squamous cell carcinoma (ESCC), as their role in ESCC is unknown. METHODS: Eosinophils were enumerated in tissues from 2 ESCC cohorts. Mice were treated with 4-NQO for 8 weeks to induce precancer or 16 weeks to induce carcinoma. The eosinophil number was modified by a monoclonal antibody to interleukin-5 (IL5mAb), recombinant IL-5 (rIL-5), or genetically with eosinophil-deficient (ΔdblGATA) mice or mice deficient in eosinophil chemoattractant eotaxin-1 (Ccl11-/-). Esophageal tissue and eosinophil-specific RNA sequencing was performed to understand eosinophil function. Three-dimensional coculturing of eosinophils with precancer or cancer cells was done to ascertain direct effects of eosinophils. RESULTS: Activated eosinophils are present in higher numbers in early-stage vs late-stage ESCC. Mice treated with 4-NQO exhibit more esophageal eosinophils in precancer vs cancer. Correspondingly, epithelial cell Ccl11 expression is higher in mice with precancer. Eosinophil depletion using 3 mouse models (Ccl11-/- mice, ΔdblGATA mice, IL5mAb treatment) all display exacerbated 4-NQO tumorigenesis. Conversely, treatment with rIL-5 increases esophageal eosinophilia and protects against precancer and carcinoma. Tissue and eosinophil RNA sequencing revealed eosinophils drive oxidative stress in precancer. In vitro coculturing of eosinophils with precancer or cancer cells resulted in increased apoptosis in the presence of a degranulating agent, which is reversed with NAC, a reactive oxygen species scavenger. ΔdblGATA mice exhibited increased CD4 T cell infiltration, IL-17, and enrichment of IL-17 protumorigenic pathways. CONCLUSION: Eosinophils likely protect against ESCC through reactive oxygen species release during degranulation and suppression of IL-17.


Asunto(s)
Carcinoma , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Animales , Ratones , Eosinófilos , Interleucina-17 , Especies Reactivas de Oxígeno
15.
bioRxiv ; 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37333285

RESUMEN

Background/Aims: Eosinophils are present in several solid tumors and have context-dependent function. Our aim is to define the contribution of eosinophils in esophageal squamous cell carcinoma (ESCC), since their role in ESCC is unknown. Methods: Eosinophils were enumerated in tissues from two ESCC cohorts. Mice were treated with 4-nitroquinolone-1-oxide (4-NQO) for 8 weeks to induce pre-cancer or 16 weeks to induce carcinoma. Eosinophil number was modified by monoclonal antibody to IL-5 (IL5mAb), recombinant IL-5 (rIL-5), or genetically with eosinophil-deficient (ΔdblGATA) mice or mice deficient in eosinophil chemoattractant eotaxin-1 ( Ccl11 -/- ). Esophageal tissue and eosinophil specific RNA-sequencing was performed to understand eosinophil function. 3-D co-culturing of eosinophils with pre-cancer or cancer cells was done to ascertain direct effects of eosinophils. Results: Activated eosinophils are present in higher numbers in early stage versus late stage ESCC. Mice treated with 4-NQO exhibit more esophageal eosinophils in pre-cancer versus cancer. Correspondingly, epithelial cell Ccl11 expression is higher in mice with pre-cancer. Eosinophil depletion using three mouse models ( Ccl11 -/- mice, ΔdblGATA mice, IL5mAb treatment) all display exacerbated 4-NQO tumorigenesis. Conversely, treatment with rIL-5 increases esophageal eosinophilia and protects against pre-cancer and carcinoma. Tissue and eosinophil RNA-sequencing revealed eosinophils drive oxidative stress in pre-cancer. In vitro co-culturing of eosinophils with pre-cancer or cancer cells resulted in increased apoptosis in the presence of a degranulating agent, which is reversed with N-acetylcysteine, a reactive oxygen species (ROS) scavenger. ΔdblGATA mice exhibited increased CD4 T cell infiltration, IL-17, and enrichment of IL-17 pro-tumorigenic pathways. Conclusion: Eosinophils likely protect against ESCC through ROS release during degranulation and suppression of IL-17.

16.
Gut Microbes ; 15(1): 2225841, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37350393

RESUMEN

BACKGROUND & AIM: Clostridioides difficile infection (CDI) is the leading cause of hospital-acquired diarrhea and pseudomembranous colitis. Two protein toxins, TcdA and TcdB, produced by C. difficile are the major determinants of disease. However, the pathophysiological causes of diarrhea during CDI are not well understood. Here, we investigated the effects of C. difficile toxins on paracellular permeability and apical ion transporters in the context of an acute physiological infection. METHODS: We studied intestinal permeability and apical membrane transporters in female C57BL/6J mice. Üssing chambers were used to measure paracellular permeability and ion transporter function across the intestinal tract. Infected intestinal tissues were analyzed by immunofluorescence microscopy and RNA-sequencing to uncover mechanisms of transporter dysregulation. RESULTS: Intestinal permeability was increased through the size-selective leak pathway in vivo during acute CDI in a 2-day-post infection model. Chloride secretory activity was reduced in the cecum and distal colon during infection by decreased CaCC and CFTR function, respectively. SGLT1 activity was significantly reduced in the cecum and colon, accompanied by ablated SGLT1 expression in colonocytes and increased luminal glucose concentrations. SGLT1 and DRA expression was ablated by either TcdA or TcdB during acute infection, but NHE3 was decreased in a TcdB-dependent manner. The localization of key proteins that link filamentous actin to the ion transporters in the apical plasma membrane was unchanged. However, Sglt1, Nhe3, and Dra were drastically reduced at the transcript level, implicating downregulation of ion transporters in the mechanism of diarrhea during CDI. CONCLUSIONS: CDI increases intestinal permeability and decreases apical abundance of NHE3, SGLT1, and DRA. This combination likely leads to dysfunctional water and solute absorption in the large bowel, causing osmotic diarrhea. These findings provide insights into the pathophysiological mechanisms underlying diarrhea and may open novel avenues for attenuating CDI-associated diarrhea.


Asunto(s)
Toxinas Bacterianas , Clostridioides difficile , Infecciones por Clostridium , Microbioma Gastrointestinal , Animales , Femenino , Ratones , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/metabolismo , Clostridioides difficile/genética , Clostridioides difficile/metabolismo , Diarrea , Regulación hacia Abajo , Ratones Endogámicos C57BL , Permeabilidad , Intercambiador 3 de Sodio-Hidrógeno/genética , Intercambiador 3 de Sodio-Hidrógeno/metabolismo
17.
CA Cancer J Clin ; 73(6): 590-596, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37358310

RESUMEN

The standard for cancer staging in the United States for all cancer sites, including primary carcinomas of the appendix, is the American Joint Committee on Cancer (AJCC) staging system. AJCC staging criteria undergo periodic revisions, led by a panel of site-specific experts, to maintain contemporary staging definitions through the evaluation of new evidence. Since its last revision, the AJCC has restructured its processes to include prospectively collected data because large data sets have become increasingly robust and available over time. Thus survival analyses using AJCC eighth edition staging criteria were used to inform stage group revisions in the version 9 AJCC staging system, including appendiceal cancer. Although the current AJCC staging definitions were maintained for appendiceal cancer, incorporating survival analysis into the version 9 staging system provided unique insight into the clinical challenges in staging rare malignancies. This article highlights the critical clinical components of the now published version 9 AJCC staging system for appendix cancer, which (1) justified the separation of three different histologies (non-mucinous, mucinous, signet-ring cell) in terms of prognostic variance, (2) demonstrated the clinical implications and challenges in staging heterogeneous and rare tumors, and (3) emphasized the influence of data limitations on survival analysis for low-grade appendiceal mucinous neoplasms.


Asunto(s)
Neoplasias del Apéndice , Humanos , Estados Unidos , Neoplasias del Apéndice/patología , Estadificación de Neoplasias , Pronóstico , Análisis de Supervivencia
18.
Gastroenterology ; 165(3): 656-669.e8, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37271289

RESUMEN

BACKGROUND & AIMS: The amino acid hypusine, synthesized from the polyamine spermidine by the enzyme deoxyhypusine synthase (DHPS), is essential for the activity of eukaryotic translation initiation factor 5A (EIF5A). The role of hypusinated EIF5A (EIF5AHyp) remains unknown in intestinal homeostasis. Our aim was to investigate EIF5AHyp in the gut epithelium in inflammation and carcinogenesis. METHODS: We used human colon tissue messenger RNA samples and publicly available transcriptomic datasets, tissue microarrays, and patient-derived colon organoids. Mice with intestinal epithelial-specific deletion of Dhps were investigated at baseline and in models of colitis and colon carcinogenesis. RESULTS: We found that patients with ulcerative colitis and Crohn's disease exhibit reduced colon levels of DHPS messenger RNA and DHPS protein and reduced levels of EIF5AHyp. Similarly, colonic organoids from colitis patients also show down-regulated DHPS expression. Mice with intestinal epithelial-specific deletion of Dhps develop spontaneous colon hyperplasia, epithelial proliferation, crypt distortion, and inflammation. Furthermore, these mice are highly susceptible to experimental colitis and show exacerbated colon tumorigenesis when treated with a carcinogen. Transcriptomic and proteomic analysis on colonic epithelial cells demonstrated that loss of hypusination induces multiple pathways related to cancer and immune response. Moreover, we found that hypusination enhances translation of numerous enzymes involved in aldehyde detoxification, including glutathione S-transferases and aldehyde dehydrogenases. Accordingly, hypusination-deficient mice exhibit increased levels of aldehyde adducts in the colon, and their treatment with a scavenger of electrophiles reduces colitis. CONCLUSIONS: Hypusination in intestinal epithelial cells has a key role in the prevention of colitis and colorectal cancer, and enhancement of this pathway via supplementation of spermidine could have a therapeutic impact.


Asunto(s)
Colitis , Espermidina , Humanos , Animales , Ratones , Espermidina/farmacología , Espermidina/metabolismo , Proteómica , Factores de Iniciación de Péptidos/genética , Factores de Iniciación de Péptidos/metabolismo , Carcinogénesis/genética , Colitis/inducido químicamente , Colitis/genética , Colitis/prevención & control , Homeostasis , Inflamación
19.
J Clin Invest ; 133(13)2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37166989

RESUMEN

Although selenium deficiency correlates with colorectal cancer (CRC) risk, the roles of the selenium-rich antioxidant selenoprotein P (SELENOP) in CRC remain unclear. In this study, we defined SELENOP's contributions to sporadic CRC. In human single-cell cRNA-Seq (scRNA-Seq) data sets, we discovered that SELENOP expression rose as normal colon stem cells transformed into adenomas that progressed into carcinomas. We next examined the effects of Selenop KO in a mouse adenoma model that involved conditional, intestinal epithelium-specific deletion of the tumor suppressor adenomatous polyposis coli (Apc) and found that Selenop KO decreased colon tumor incidence and size. We mechanistically interrogated SELENOP-driven phenotypes in tumor organoids as well as in CRC and noncancer cell lines. Selenop-KO tumor organoids demonstrated defects in organoid formation and decreases in WNT target gene expression, which could be reversed by SELENOP restoration. Moreover, SELENOP increased canonical WNT signaling activity in noncancer and CRC cell lines. In defining the mechanism of action of SELENOP, we mapped protein-protein interactions between SELENOP and the WNT coreceptors low-density lipoprotein receptor-related proteins 5 and 6 (LRP5/6). Last, we confirmed that SELENOP-LRP5/6 interactions contributed to the effects of SELENOP on WNT activity. Overall, our results position SELENOP as a modulator of the WNT signaling pathway in sporadic CRC.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Selenio , Ratones , Animales , Humanos , Vía de Señalización Wnt , Selenoproteína P/genética , Selenoproteína P/metabolismo , Neoplasias Colorrectales/patología , Selenio/metabolismo , Carcinogénesis/genética , Adenoma/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteína-5 Relacionada con Receptor de Lipoproteína de Baja Densidad/genética , Proteína-5 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo
20.
CA Cancer J Clin ; 73(5): 516-523, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37114458

RESUMEN

The American Joint Committee on Cancer (AJCC) staging system for all cancer sites, including anal cancer, is the standard for cancer staging in the United States. The AJCC staging criteria are dynamic, and periodic updates are conducted to optimize AJCC staging definitions through a panel of experts charged with evaluating new evidence to implement changes. With greater availability of large data sets, the AJCC has since restructured and updated its processes, incorporating prospectively collected data to validate stage group revisions in the version 9 AJCC staging system, including anal cancer. Survival analysis using AJCC eighth edition staging guidelines revealed a lack of hierarchical order in which stage IIIA anal cancer was associated with a better prognosis than stage IIB disease, suggesting that, for anal cancer, tumor (T) category has a greater effect on survival than lymph node (N) category. Accordingly, version 9 stage groups have been appropriately adjusted to reflect contemporary long-term outcomes. This article highlights the changes to the now published AJCC staging system for anal cancer, which: (1) redefined stage IIB as T1-T2N1M0 disease, (2) redefined stage IIIA as T3N0-N1M0 disease, and (3) eliminated stage 0 disease from its guidelines altogether.


Asunto(s)
Neoplasias del Ano , Humanos , Estados Unidos , Estadificación de Neoplasias , Pronóstico , Análisis de Supervivencia , Neoplasias del Ano/diagnóstico
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