323 research outputs found
The new (Version 9) American Joint Committee on Cancer tumor, node, metastasis staging for cervical cancer
The American Joint Committee on Cancer (AJCC) tumor, node, metastasis (TNM) staging for all cancer sites has been periodically updated as a published manual for many years. The last update, the eighth edition AJCC Cancer Staging Manual went into use on January 1, 2018. The AJCC has since restructured and updated its processes, and all AJCC staging-related data are now housed on its new application programming interface. Consequently, the next AJCC TNM staging update, AJCC version 9 TNM staging, will be published electronically and will be released chapter by chapter. The first chapter of version 9 AJCC TNM staging is the updated cervical cancer staging, which is now published. This article highlights the changes to the AJCC TNM cervical cancer staging; these changes align with the International Federation of Gynecology and Obstetrics staging. The most important of the changes are: 1) the incorporation of imaging and surgical findings, 2) the elimination of lateral spread from T1a, 3) the addition of a subcategory to T1b (T1b3), and 4) histopathology is updated to reflect human papillomavirus-associated and human papillomavirus-independent carcinomas
Identification of pathologic features associated with āulcerative colitis-likeā Crohnās disease
AIM: To identify pathologic features associated with this āulcerative colitis (UC)-likeā subgroup of Crohnās disease (CD). METHODS: Seventeen subjects diagnosed as having UC who underwent proctocolectomy (RPC) from 2003-2007 and subsequently developed CD of the ileal pouch were identified. UC was diagnosed based on pre-operative clinical, endoscopic, and pathologic studies. Eighteen patients who underwent RPC for UC within the same time period without subsequently developing CD were randomly selected and used as controls. Pathology reports and histological slides were reviewed for a wide range of gross and microscopic pathological features, as well as extent of disease. The demographics, gross description and histopathology of the resection specimens were reviewed and compared between the two groups. RESULTS: Patients with āUC-likeā CD were on average 13 years younger than those with ātrueā UC (P < 0.01). More severe disease in the proximal involved region and active ileitis with/without architectural distortion were observed in 6 of 17 (35%) and 7 of 17 (41%) āUC-likeā CD cases, respectively, but in none of the ātrueā UC cases (P < 0.05). Active appendicitis occurred in 8 of 16 (50%) āUC-likeā CD cases but in only two (11%) ātrueā UC cases (P < 0.05). Conspicuous lamina propria neutrophils were more specific for āUC-likeā CD (76% vs 22%, P < 0.05). In addition, prominent lymphoid aggregates tended to be more common in āUC-likeā CD (P = 0.07). The ātrueā UC group contained a greater number of cases with severe activity (78% vs 47%). Therefore, the features more commonly seen in āUC-likeā CD were not due to a more severe disease process. Crohnās granulomas and transmural inflammation in non-ulcerated areas were absent in both groups. CONCLUSION: More severe disease in the proximal involved region, terminal ileum involvement, active appendicitis, and prominent lamina propria neutrophils may be morphological factors associated with āUC-likeā CD
Comparison of Biomarker Expression between Proximal and Distal Colorectal Adenomas: The Tennessee-Indiana Adenoma Recurrence Study
It is unclear if proximal and distal traditional adenomas present with differences in molecular events which contribute to cancer heterogeneity by tumor anatomical subsite. Participants from a colonoscopy-based study (n=380) were divided into subgroups based on the location of their most advanced adenoma: proximal, distal, or āequivalent both sidesā. Eight biomarkers in the most advanced adenomas were evaluated by immunohistochemistry (Ki-67, COX-2, TGFĪ²RII, EGFR, Ī²-catenin, cyclin D1, c-Myc) or TUNEL (apoptosis). After an adjustment for pathological features, there were no significant differences between proximal and distal adenomas for any biomarker. Conversely, expression levels did vary by other features, such as their size, villous component, and synchronousness. Large adenomas had higher expression levels of Ki-67(P<0.001), TGFĪ²RII (P<0.0001), c-Myc (P<0.001), and cyclin D1 (P<0.001) in comparison to small adenomas, and tubulovillous/villous adenomas also were more likely to have similar higher expression levels in comparison to tubular adenomas. Adenoma location is not a major determinant of the expression of these biomarkers outside of other pathological features. This study suggests similarly important roles of Wnt/Ī²-catenin and TGF-Ī² pathways in carcinogenesis in both the proximal and distal colorectum
Are ulcers a marker for invasive carcinoma in barrett's esophagus? data from a diagnostic variability study with clinical follow-up
We correlated follow-up information from 138 patients with Barrett's esophagus and varying degrees of dysplasia with the presence of ulcers. Methods A group of pathologist participants were asked to contribute patientsā initial biopsy slides showing Barrett's esophagus (BE) without dysplasia and with epithelial changes indefinite for dysplasia, low grade dysplasia (LGD), high grade dysplasia (HGD), and adenocarcinoma. From the initial 250 cases used for a diagnostic reproducibility study, follow-up information was available for 138 patients. Results There were 44 cases submitted as BE, 22 as BE with epithelial changes indefinite for dysplasia, 26 as BE with LGD, 33 as BE with HGD, and 13 as BE with adenocarcinoma. Ulcers were present in 35/138 cases (25%), including 3/44 cases of BE without dysplasia (7%), 2/22 cases of BE with epithelial changes indefinite for dysplasia (9%), 0/26 cases of BE with LGD (0%), 10/33 cases of BE with HGD (30%), and 7/13 cases of BE with adenocarcinoma (54%). On follow-up, there were no invasive carcinomas detected among the BE without dysplasia group (median follow-up = 38.5 months). Adenocarcinomas were detected in 4/22 cases (18%) submitted as BE with epithelial changes indefinite for dysplasia at 19, 55, 60, and 62 months and in 4/26 cases (15%) of BE with LGD at 9, 9, 11, and 60 months. None of these carcinomas occurred in cases in which an ulcer was present in the initial biopsy specimen. Among the 33 HGD cases, 20 (60%) were found to have adenocarcinoma on subsequent resection specimens. The presence of an ulcer with HGD increased the likelihood of finding carcinoma in the resection specimen, as 8/10 biopsies (80%) of HGD patients with ulcers had carcinoma, compared to 12/23 biopsies (52%) of HGD patients without ulcers. All of the cases interpreted as adenocarcinomas on biopsy were found either to have invasive carcinoma on esophageal resection or to have metastases that were demonstrated in unresectable patients. Conclusion If an ulcer accompanies HGD in a biopsy specimen from a patient with BE, it is likely that invasive carcinoma is also present at that time.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75186/1/j.1572-0241.2002.05420.x.pd
Glucosyltransferase-dependent and independent effects of Clostridioides difficile toxins during infection
Clostridioides difficile infection (CDI) is the leading cause of nosocomial diarrhea and pseudomembranous colitis in the USA. In addition to these symptoms, patients with CDI can develop severe inflammation and tissue damage, resulting in life-threatening toxic megacolon. CDI is mediated by two large homologous protein toxins, TcdA and TcdB, that bind and hijack receptors to enter host cells where they use glucosyltransferase (GT) enzymes to inactivate Rho family GTPases. GT-dependent intoxication elicits cytopathic changes, cytokine production, and apoptosis. At higher concentrations TcdB induces GT-independent necrosis in cells and tissue by stimulating production of reactive oxygen species via recruitment of the NADPH oxidase complex. Although GT-independent necrosis has been observed in vitro, the relevance of this mechanism during CDI has remained an outstanding question in the field. In this study we generated novel C. difficile toxin mutants in the hypervirulent BI/NAP1/PCR-ribotype 027 R20291 strain to test the hypothesis that GT-independent epithelial damage occurs during CDI. Using the mouse model of CDI, we observed that epithelial damage occurs through a GT-independent process that does not involve immune cell influx. The GT-activity of either toxin was sufficient to cause severe edema and inflammation, yet GT activity of both toxins was necessary to produce severe watery diarrhea. These results demonstrate that both TcdA and TcdB contribute to disease pathogenesis when present. Further, while inactivating GT activity of C. difficile toxins may suppress diarrhea and deleterious GT-dependent immune responses, the potential of severe GT-independent epithelial damage merits consideration when developing toxin-based therapeutics against CDI
mPGES-1-Mediated Production of PGE2 and EP4 Receptor Sensing Regulate T Cell Colonic Inflammation
PGE2 is a lipid mediator of the initiation and resolution phases of inflammation, as well as a regulator of immune system responses to inflammatory events. PGE2 is produced and sensed by T cells, and autocrine or paracrine PGE2 can affect T cell phenotype and function. In this study, we use a T cell-dependent model of colitis to evaluate the role of PGE2 on pathological outcome and T-cell phenotypes. CD4+ T effector cells either deficient in mPGES-1 or the PGE2 receptor EP4 are less colitogenic. Absence of T cell autocrine mPGES1-dependent PGE2 reduces colitogenicity in association with an increase in CD4+RORĪ³t+ cells in the lamina propria. In contrast, recipient mice deficient in mPGES-1 exhibit more severe colitis that corresponds with a reduced capacity to generate FoxP3+ T cells, especially in mesenteric lymph nodes. Thus, our research defines how mPGES-1-driven production of PGE2 by different cell types in distinct intestinal locations impacts T cell function during colitis. We conclude that PGE2 has profound effects on T cell phenotype that are dependent on the microenvironment
MTG16 regulates colonic epithelial differentiation, colitis, and tumorigenesis by repressing E protein transcription factors
Aberrant epithelial differentiation and regeneration contribute to colon pathologies, including inflammatory bowel disease (iBD) and colitis-associated cancer (CAC). Myeloid translocation gene 16 (MTG16, also known as CBFA2T3) is a transcriptional corepressor expressed in the colonic epithelium. MTG16 deficiency in mice exacerbates colitis and increases tumor burden in CAC, though the underlying mechanisms remain unclear. Here, we identified MTG16 as a central mediator of epithelial differentiation, promoting goblet and restraining enteroendocrine cell development in homeostasis and enabling regeneration following dextran sulfate sodium-induced (DSS-induced) colitis. Transcriptomic analyses implicated increased Ephrussi box-binding transcription factor (E protein) activity in MTG16-deficient colon crypts. Using a mouse model with a point mutation that attenuates MTG16:E protein interactions (Mtg16(P20ST)), we showed that MTG16 exerts control over colonic epithelial differentiation and regeneration by repressing E protein-mediated transcription. Mimicking murine colitis, MTG16 expression was increased in biopsies from patients with active IBD compared with unaffected controls. Finally, uncoupling MTG16:E protein interactions partially phenocopied the enhanced tumorigenicity of Mtg16(-/)(-) colon in the azoxymethane/DSS-induced model of CAC, indicating that MTG16 protects from tumorigenesis through additional mechanisms. Collectively, our results demonstrate that MTG16, via its repression of E protein targets. is a key regulator of cell fate decisions during colon homeostasis, colitis, and cancer.Peer reviewe
A nucleotide binding rectification Brownian ratchet model for translocation of Y-family DNA polymerases
Y-family DNA polymerases are characterized by low-fidelity synthesis on undamaged DNA and ability to catalyze translesion synthesis over the damaged DNA. Their translocation along the DNA template is an important event during processive DNA synthesis. In this work we present a Brownian ratchet model for this translocation, where the directed translocation is rectified by the nucleotide binding to the polymerase. Using the model, different features of the available structures for Dpo4, Dbh and polymerase Ī¹ in binary and ternary forms can be easily explained. Other dynamic properties of the Y-family polymerases such as the fast translocation event upon dNTP binding for Dpo4 and the considerable variations of the processivity among the polymerases can also be well explained by using the model. In addition, some predicted results of the DNA synthesis rate versus the external force acting on Dpo4 and Dbh polymerases are presented. Moreover, we compare the effect of the external force on the DNA synthesis rate of the Y-family polymerase with that of the replicative DNA polymerase
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