Agonist anti-ChemR23 mAb reduces tissue neutrophil accumulation and triggers chronic inflammation resolution.

Resolution of inflammation is elicited by proresolving lipids, which activate GPCRs to induce neutrophil apoptosis, reduce neutrophil tissue recruitment, and promote macrophage efferocytosis. Transcriptional analyses in up to 300 patients with Inflammatory Bowel Disease (IBD) identified potential therapeutic targets mediating chronic inflammation. We found that ChemR23, a GPCR targeted by resolvin E1, is overexpressed in inflamed colon tissues of severe IBD patients unresponsive to anti-TNFα or anti-α4ß7 therapies and associated with significant mucosal neutrophil accumulation. We also identified an anti-ChemR23 agonist antibody that induces receptor signaling, promotes macrophage efferocytosis, and reduces neutrophil apoptosis at the site of inflammation. This ChemR23 mAb accelerated acute inflammation resolution and triggered resolution in ongoing chronic colitis models, with a significant decrease in tissue lesions, fibrosis and inflammation-driven tumors. Our findings suggest that failure of current IBD therapies may be associated with neutrophil infiltration and that ChemR23 is a promising therapeutic target for chronic inflammation.

Loss of SMARCB1 expression in colon carcinoma.

SMARCB1 is a tumor suppressor gene, which is part of SWI/SNF complex involved in transcriptional regulation. Recently, loss of SMARCB1 expression has been reported in gastrointestinal carcinomas. Our purpose was to evaluate the incidence and prognostic value of SMARCB1 loss in colon carcinoma (CC). Patients with stage III CC (n= 1695), and a second cohort of 23 patients with poorly differentiated CC were analyzed. Immunohistochemistry for SMARCB1 was performed on tissue microarrays, and cases with loss of expression were controlled on whole sections. Loss of SMARCB1 was compared with the clinico-pathological and molecular characteristics, and the prognostic value was evaluated. Loss of SMARCB1 was identified in 12 of 1695 (0.7%) patients with stage III CC. Whole section controls showed a complete loss in only one of these cases, corresponding to a medullary carcinoma. SMARCB1 loss was not associated with histological grade, tumor size nor survival. In the cohort of poorly differentiated CC, we detected 2/23 (8.7%) cases with loss of SMARCB1; one was rhabdoid while the other had medullary and mucinous histology. These 2 cases were deficient for MisMatched Repair (dMMR) and mutated for BRAF. SMARCB1 loss is rare in stage III CC, but appears more frequent in poorly differentiated CC.

Model predicting the ypN0 status after good response to chemoradiotherapy in rectal cancer.

BACKGROUND: The purpose of this study was to identify the predictive factors for ypN0 status in tumors with good pathologic response to chemoradiotherapy (CRT). METHODS: A retrospective chart review was conducted on patients at two tertiary cancer center who underwent rectal resection after good response to CRT between 2000 and 2013. RESULTS: No preoperative treatment (oxaliplatin use, radiotherapy boost of 5,4 Gy, delay CRT-surgery) impacted on the ypN status. In the multivariate analysis, only a ypT<3 (HR 7.5 [2,9-19.5]) was significant and no lymphovascular invasion (HR 8,9 [1.6-49.8]) was limited to significance.The best model predicting the ypN0 status used only the ypT status<3. The major part (92.2%) of patients with ypT0-2 tumors had no LN invasion. CONCLUSION: The risk of lymph node involvement metastases was only 7.8% for the patients with an ypT0-2 status. A fullthickness transanal resection coud be the futur treatment of these patients.

Subversion of human intestinal mucosa innate immunity by a Crohn's disease-associated E. coli.

Adherent-invasive Escherichia coli (AIEC), associated with Crohn's disease, are likely candidate contributory factors in the disease. However, signaling pathways involved in human intestinal mucosa innate host response to AIEC remain unknown. Here we use a 3D model of human intestinal mucosa explant culture to explore the effects of the AIEC strain LF82 on two innate immunity platforms, i.e., the inflammasome through evaluation of caspase-1 status, and NFκB signaling. We showed that LF82 bacteria enter and survive within a few intestinal epithelial cells and macrophages, without altering the mucosa overall architecture. Although 4-h infection with a Salmonella strain caused crypt disorganization, caspase-1 activation, and mature IL-18 production, LF82 bacteria were unable to activate caspase-1 and induce IL-18 production. In parallel, LF82 bacteria activated NFκB signaling in epithelial cells through IκBα phosphorylation, NFκBp65 nuclear translocation, and TNFα secretion. In addition, NFκB activation was crucial for the maintenance of epithelial homeostasis upon LF82 infection. In conclusion, here we decipher at the whole-mucosa level the mechanisms of the LF82-induced subversion of innate immunity that, by maintaining host cell integrity, ensure intracellular bacteria survival.

Increased Th17/Treg ratio in chronic liver GVHD.

The contribution of Th17 cells to chronic GVHD (cGVHD) has been demonstrated in cGVHD mouse models. However, their contribution to human liver cGVHD remains unclear. We evaluated Th17 cells in biopsies from a cohort of 17 patients with liver cGVHD. We observed a significant increase in Th17 cells in the liver of patients with cGVHD, as demonstrated by an increase in CCR6+, CD161+ and RORγt+ T cells (P=0.03, P=0.0001 and P=0.03, respectively). We also assessed the presence of Th1 and regulatory (Treg) T cells: the numbers of Th1 and Treg cells were very low, with no difference between the two groups (P=0.88 and P=0.12, respectively). Furthermore, Th17/Th1 and Th17/Treg ratios were significantly increased in the liver of patients with liver cGVHD (P=0.005 and P=0.002, respectively). This study provides evidence for an infiltration by Th17 cells in the liver of patients with cGVHD and an increased Th17/Treg ratio, suggesting a defect in the regulatory mechanism driven by Treg cells or an inappropriate activation of effectors cells, especially Th17 cells, or both mechanisms, in human liver cGVHD.

Plasmacytoid dendritic cells and Th17 immune response contribution in gastrointestinal acute graft-versus-host disease.

The contribution of Th17 cells in acute graft-versus-host disease (aGVHD) has been demonstrated in aGVHD mouse models. However, their contribution in human gastrointestinal aGVHD remains unclear. We evaluated Th17 cells in a cohort of 23 patients at diagnosis of aGVHD. In this study, we have shown that the absolute number of Th17 cells using the CCR6 and CD161 markers were significantly higher in the intestinal mucosa of patients with aGVHD compared with intestinal mucosa of patients without aGVHD. Moreover, in keeping with the increase of CCR6+ and CD161+ T cells, RORγt the key transcription factor that orchestrates the differentiation of Th17 cells, was significantly increased in the intestinal mucosa of patients with aGVHD compared with intestinal mucosa of patients without aGVHD (P=0.01). Since plasmacytoid dendritic cells (PDCs) have been reported to drive the differentiation of the Th17 subset, we quantified PDCs in these patients. PDC CD123+ cells were increased in the intestinal mucosa of patients with aGVHD. Furthermore, the number of CD123+ PDCs paralleled the histological grade of aGVHD, providing evidence for a role of Th17-mediated responses and a potential new pathophysiological link between PDCs and Th17 in human aGVHD.

Colonic mucosal biopsies obtained during confocal endomicroscopy are pre-stained with fluorescein in vivo and are suitable for histologic evaluation.

BACKGROUND AND STUDY AIMS: Confocal laser endomicroscopy (CLE) with intravenous infusion of fluorescein allows noninvasive, real-time in vivo visualization of gastrointestinal mucosa at ~ × 1000 magnification ("virtual biopsy"). Conventional biopsies obtained during these procedures serve as the reference and established diagnostic standard. The aim of the present study was to assess whether the standard histologic biopsies that are obtained during CLE retain fluorescein in the tissues and allow the visualization of mucosal structures without any additional staining. PATIENTS AND METHODS: CLE optical imaging of the mucosa was performed in 16 patients who were undergoing CLE colonoscopy. Standard conventional biopsies were also obtained from both normal colonic mucosa and colonic polyps. De-paraffinized mucosal sections were examined under a fluorescence microscope for the presence and distribution of fluorescein, and then underwent immunostaining for expression of vascular endothelial growth factor (VEGF). RESULTS: Standard mucosal biopsy sections from patients undergoing CLE displayed a strong fluorescence and showed well-delineated mucosal structures. In colonic adenomas, there was a 4.6-fold increased vascular permeability compared with normal mucosa (P<0.001), indicated by fluorescein leakage to the extravascular space. Immunostaining demonstrated an aberrantly increased expression of VEGF in the epithelium of colonic adenomas but not in the epithelium of normal mucosa or hyperplastic polyps. CONCLUSIONS: This study shows for the first time that standard colonic biopsies obtained during CLE retain fluorescein, show excellent delineation of mucosal structures without additional staining, allow the evaluation of mucosal microvasculature and vascular permeability, and are suitable for immunostaining.

In vivo real-time imaging of human duodenal mucosal structures in celiac disease using endocytoscopy.

BACKGROUND AND AIMS: Celiac disease is a gluten-induced enteropathy whose diagnosis is based on histological evidence of villous atrophy. The diagnosis may be difficult if the orientation of histological sections is other than optimal. During upper gastrointestinal endoscopy we studied in vivo duodenal mucosa in patients with celiac disease using endocytoscopy, a novel diagnostic technique allowing in vivo real-time visualization of mucosa under x 450 magnification. METHODS: Sixteen patients with documented celiac disease and seven controls without celiac disease were studied. Endocytoscopic images obtained from several fields were compared in a blinded fashion to standard histology. RESULTS: Endocytoscopy showed three different patterns of in vivo histology: (1) the presence of normal-appearing, long, thin villi, lined with clearly distinguishable surface epithelial cells, considered to be normal duodenal mucosa (n = 15, all controls and eight celiac disease patients); (2) the presence of thick, shortened villi, reflecting partial villous atrophy (n = 4); and (3) the total absence of villi and the presence of enlarged crypt orifices, reflecting total villous atrophy (n = 4). Good concordance between endocytoscopy and standard histology was found in all 16 patients with celiac disease. CONCLUSIONS: Endocytoscopy allows in vivo, real-time, noninvasive visualization and characterization of villous architecture and may be a promising method for in vivo evaluation of duodenal mucosa in celiac disease.

Endoscopic ultrasound-guided fine-needle aspiration for the diagnosis of solid pancreatic masses: the impact on patient-management strategy.

BACKGROUND: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe and accurate technique for diagnosing pancreatic cancer. However, its impact for management of these patients is poorly investigated. AIMS: To investigate the diagnostic yield and the therapeutic impact of EUS-FNA in the management of solid pancreatic masses. METHODS: One hundred consecutive patients who underwent EUS-FNA for a solid pancreatic mass were included. Aspirates were placed onto glass slides for cytological examination and microbiopsies were fixed in formaldehyde for histology. The impact on clinical management was analysed retrospectively according to different endpoints, such as its impact on indications for chemotherapy, surgery or appropriate follow-up modality. RESULTS: Eight procedures were considered failures and two patients were lost to follow-up. A final diagnosis was obtained in 90 patients. The sensitivity, specificity and accuracy of combined cytology and histology for the diagnosis of malignant or potentially-malignant tumours were 78%, 75%, and 78% respectively. The sensitivity and accuracy of cytology alone were significantly higher than those of histology alone (P = 0.0003). By intention-to-diagnose analysis, EUS-FNA directly influenced the management strategy in 62 of 100 patients. CONCLUSIONS: In patients with pancreatic mass and suspected malignancy, EUS-FNA provides an accurate diagnosis in approximately 80% of cases. EUS-FNA directly influences the management in two-thirds of patients.

Prognostic impact of syndecan-1 expression in invasive ductal breast carcinomas.

Carcinoma cells lack syndecan-1 expression when they are transiting from an epithelial to a less-differentiated mesenchymal phenotype (epithelial-mesenchymal transition, EMT). Furthermore, a shift of syndecan-1 expression from malignant epithelial cells to reactive stromal cells has also been observed during progression of many carcinomas. Finally, epithelial and/or stromal syndecan-1 expression is of prognostic value in many carcinomas. Because recent results are contradictory in breast carcinomas, we have re-evaluated the prognostic significance of syndecan-1 expression in a cohort of 80 patients with invasive ductal breast carcinomas. The tumours from 80 patients diagnosed with invasive ductal breast carcinomas were used to construct a tissue microarray, which was stained with syndecan-1 by immunohistochemistry. We correlated syndecan-1 expression with clinicopathologic parameters and relapse-free survival (RFS). Exclusive epithelial expression of syndecan-1 is observed in 61.25% of the patients, whereas exclusive stromal expression is observed in 30% of the patients. Only 8.75% of the patients had both stromal and epithelial expressions of syndecan-1. A significant correlation was found between the loss of syndecan-1 epithelial expression and the syndecan-1 stromal expression with high grade of malignancy (P=0.011). The loss of syndecan-1 epithelial expression is correlated with RFS (P=0.001). Using multivariate Cox analysis, loss of epithelial syndecan-1 expression was the only prognostic indicator (P<0.001). We concluded that the loss of syndecan-1 epithelial expression was of strong prognostic value in breast carcinomas.

[Histopathology of central nervous system cavernomas]. / Anatomie pathologique des cavernomes du système nerveux central.

Central nervous system cavernomas are vascular malformations, which occur in two circumstances: sporadic forms and familial autosomal dominant forms. The lesion consists of enlarged, closely packed vessels without interposition of brain parenchyma, surrounded by hemosiderin and gliosis, calcified in few cases. In 80% of sporadic forms the lesion is unique, multiple lesions are rare (median: 4). In familial forms the lesions are always multiple. Cavernomas are often associated with other vascular malformations, especially with venous developmental anomalies. The size of cavernomas is variable from 1 mm to several centimeters. About 70% of cases are supratentorial and 30% in the posterior fossa, particularly in the brain stem. Macroscopic and histopathological findings are typical and the diagnostic is generally easy.

Altered Calreticulin expression in human colon cancer: maintenance of Calreticulin expression is associated with mucinous differentiation.

Calreticulin is an endoplasmic reticulum luminal calcium-binding chaperone involved in various cellular functions and is a ligand for the scavenger receptor CD91. Recent studies, based on proteomic approaches on whole tissue samples containing both neoplastic and non-neoplastic cells, have shown alterations of Calreticulin expression in colon carcinomas, albeit with divergent results. The aims of this study were: 1) to assess the expression of Calreticulin and its receptor CD91 in 58 human colon adenocarcinomas, compared with paired normal mucosa, using a semi-quantitative immunohistochemical analysis, and 2) to examine associations between the tumour phenotypic features, and Calreticulin and/or CD91 expressions. Calreticulin expression was down-regulated in 51.7% human colon adenocarcinomas. Accordingly, quantitative immunoblot analysis showed that Calreticulin expression was significantly lower in human colonic cancer cell lines than in preparations of isolated human normal colonic epithelial cells. CD91 was co-expressed with Calreticulin in both normal colonic epithelial cells and pericryptic myofibroblasts. Calreticulin and CD91, that characterize the 'amateur phagocyte' function of epithelial cells, were both down-regulated in 48% of adenocarcinomas. Finally, Calreticulin expression was significantly associated with the mucinous differentiation of the tumour. Collectively, these results show that Calreticulin is likely to play a pivotal role in the differentiation of human colonic adenocarcinomas.

Phosphohistone H3 labelling for histoprognostic grading of breast adenocarcinomas and computer-assisted determination of mitotic index.

BACKGROUND: Microscopic evaluation of mitotic figures is a routine procedure in the assessment of the histoprognostic grade of tumours. Nevertheless, their count may be fraught with difficulties. As histone H3 phosphorylation at serine 10 is closely linked to chromosomal condensation, a new monoclonal antibody directed to phosphorylated histone H3 (PPH3) was recently proposed to detect mitotic cells. AIM: To test the reliability of this antibody in detecting and counting mitotic figures in sections of breast adenocarcinomas, because of the importance of mitotic count in histoprognostic grading. METHODS: The pattern of PPH3 staining in formalin-fixed paraffin wax-embedded tissues, including normal tissues and a series of 39 breast adenocarcinomas, was examined. A new computer-assisted method was also developed for determining the mitotic index. RESULTS AND CONCLUSIONS: In all tissues tested, PPH3-labelled mitotic figures were easily detected, allowing a rapid identification of the area of highest mitotic activity. In breast carcinomas, a strong correlation was observed between PPH3-stained and haematoxylin and eosin-stained mitotic counts (r = 0.86, p<0.0001). Counting of prophase nuclei that coexpress cyclin B1, a marker of the G2/M phase, was possible by PPH3 staining; its accuracy led us to reconsider the tumour grade in three cases. Finally, an automatic computer-assisted method was designed for assessing mitotic index with confocal microscopy and image-analysis software.

[Strongyloides stercoralis infection simulating polyarteritis nodosa]. / Anguillulose autochtone simulant une périartérite noueuse.

INTRODUCTION: Parasitic infection can present with many different clinical manifestations. EXEGESIS: A 77 year-old Russian woman, who's been living in France since 50 years was admitted for polyarthritis, myalgia, fever, abdominal pain, and eosinophilia simulating polyarterisis nodosa. Before admission, she was treated by steroids for polymyalgia rheumatica. The diagnosis of Strongyloides stercoralis was performed by parasitologic analysis of feces and colic biopsies. The outcome was favourable under treatment by ivermectine and steroid withdrawal. CONCLUSION: S. stercoralis can be associated with reactive arthritis. Case reports of S. stercoralis infection mimicking systemic vasculitis are exceptionnal.

[Multiple neurological complications in a case of anterior pituitary insufficiency]. / Manifestations neurologiques multiples associées à une insuffisance anté-hypophysaire.

Neurological manifestations of anterior pituitary deficiency are well known but their association remains rare. We report a woman who developed, insidiously over ten Years, a complex neurological disorder associating cognitive impairment, psychiatric disorder, cerebellar ataxia, demyelinating neuropathy, and myopathy with pseudomyotonia. After 18 Months of hormone substitution treatment, the patient fully recovered.

[Multiple actinomycosis brain abscesses]. / Abcès cérébraux multiples à Actinomyces.

BACKGROUND: Actinomycosis is a subacute or chronic bacterial infection, which can affect immunocompetent or immunodeficient subjects. It most often occurs in cervico-facial or thoracic-abdominal locations. Central nervous system infection is rare but of severe prognosis. CASE REPORT: A 56 year-old woman with no history of immunodepression was admitted with unexplained fever, inappropriate behaviour, and spatial and temporal disorientation. The progressive worsening of the neurological signs let to coma and mechanical ventilation was required. Brain imaging showed multilocation cerebral abscesses. Stereotaxial biopsy permitted diagnosis of actinomycosis. Patient's outcome was favourable following appropriate dual antibiotherapy without surgical exeresis. DISCUSSION: When lacking bacteriologic identification, diagnosis of cerebral actinomycosis is performed by pathologic findings. Dual antibiotherapy allows full recover, even in the case of multilocation cerebral abscesses.

Cyclo-oxygenase-2 over-expression in sporadic colorectal carcinoma without lymph node involvement.

BACKGROUND: Cyclo-oxygenase-2 over-expression has been reported in most advanced human colorectal cancers. AIMS: To assess the prevalence of cyclo-oxygenase-2 over-expression in non-advanced colorectal cancers, to investigate the correlation between cyclo-oxygenase-2 status and tumour clinicopathological features and molecular phenotype, and to determine the impact of cyclo-oxygenase-2 status on long-term clinical outcome. METHODS: Sixty-one patients who had undergone surgery for colorectal cancer without lymph node involvement were evaluated retrospectively. Cyclo-oxygenase-2 expression was determined by immunohistochemistry. The tumour replication error phenotype was assessed by amplification of the two microsatellites, BAT-25 and BAT-26. RESULTS: Thirty-six tumours were classified as cyclo-oxygenase-2 positive and 25 as cyclo-oxygenase-2 negative. No correlation was found between cyclo-oxygenase-2 over-expression and clinicopathological features or molecular phenotype. Cyclo-oxygenase-2 over-expression was an independent predictor of a poor prognosis. Indeed, the relative risk of tumour recurrence or death for patients with cyclo-oxygenase-2-positive tumours was 2.13 times that of patients with cyclo-oxygenase-2-negative tumours (P=0.008; 95% confidence interval, 1.22-3.73). This difference remained significant when post-operative deaths were censored in the multivariate analysis (P=0.014). CONCLUSION: Cyclo-oxygenase-2 over-expression is not associated with tumour phenotype, but is indicative of a poorer clinical outcome in patients with non-advanced colorectal carcinoma.

In vitro reconstructed mucosa-integrating Langerhans' cells.

All three-dimensional in vitro mucosal models constructed, thus far, have only been reconstituted by epithelial cells. We have developed a reconstructed oral and vaginal epithelium that integrates Langerhans' cells (LC), the dendritic cells (DC) of malpighian epithelia. The epithelium was composed of gingival or vaginal keratinocytes seeded on a de-epidermized dermis (DED) and grown in submerged culture for 2 weeks. LC precursors, obtained after differentiation of cord blood-derived CD34+ hematopoietic progenitor cells (CD34+HPC) by granulocyte macrophage-colony stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and Flt3-ligand (Flt3-L), were introduced after 6-8 days of culture into the reconstituted epithelium. The in vitro reconstituted mucosal epithelium formed a multilayered, well-differentiated epithelial structure, confirmed by the immunohistochemical expression of cytokeratins 4, 6, 10, 13, 14, 16 and involucrin. LC were identified in the basal and suprabasal epithelial layers by CD1a antigen, S100 protein and Langerin/CD207 expression, and by transmission electron microscopy. Type IV collagen was expressed at the chorio-epithelial junction, and most ultrastructural features of this junction were visualized by electron microscopy. This in vitro reconstructed gingiva or vagina integrating LC represents interesting models very similar to native tissues. Because LC play an important role in the mucosal immune system, our models could be useful for conducting studies on interactions with pathogenic agents (viruses, bacteria etc.), as well as in pharmacological, toxicological and clinical research.

[Value of percutaneous core needle biopsy in the investigation of a suspected bone tumor]. / Intérêt de la biopsie percutanée des lésions osseuses d'allure tumorale.

PURPOSE: To Determine the value of percutaneous core needle biopsy in the investigation of a suspected bone neoplasm. MATERIAL AND METHODS: We performed a retrospective study of 91 core needle biopsies performed between May 1995 and October 2001. Patients were excluded if they had a known primary carcinoma or if an infection was suspected by clinical, physical or laboratory findings. The results were correlated to the analysis of the surgical piece or, for the 28 patients who did not undergo surgery, to the clinical evolution over more than 12 months. RESULTS: The final diagnosis was metastasis in 29 cases, primary bone tumor in 36 cases and benign lesions in 25 cases. Sensitivity was 92.3% and specificity was 97.4%. For primary malignant bone tumors, results respected histology features and grade in 79.2%. In cases of mistake, because of the correlation of these results to the clinical and radiological context, the treatment of the bony malignant lesions were adapted in 95.8% of cases. Only one major complication was reported in these 91 biopsies. CONCLUSION: First intention core needle biopsy, confronted with radio-clinical context seems to have a place in the evaluation of bone lesions when a tumor is suspected. This technique, less expensive than an open biopsy and with fewer complications, is best performed as part of a multidisciplinary approach with the surgeon's collaboration.