Emmanuelle Leteurtre

Genotype–phenotype correlation in hepatocellular adenoma: New classification and relationship with HCC

Hepatocellular adenomas are benign tumors that can be difficult to diagnose. To refine their classification, we performed a comprehensive analysis of their genetic, pathological, and clinical features. A multicentric series of 96 liver tumors with a firm or possible diagnosis of hepatocellular adenoma was reviewed by liver pathologists. In all cases, the genes coding for hepatocyte nuclear factor 1α (HNF1α) and β‐catenin were sequenced. No tumors were mutated in both HNF1α and β‐catenin enabling tumors to be classified into 3 groups, according to genotype. Tumors with HNF1α mutations formed the most important group of adenomas (44 cases). They were phenotypically characterized by marked steatosis (P < 10−4), lack of cytological abnormalities (P < 10−6), and no inflammatory infiltrates (P < 10−4). In contrast, the group of tumors defined by β‐catenin activation included 13 lesions with frequent cytological abnormalities and pseudo‐glandular formation (P < 10−5). The third group of tumors without mutation was divided into two subgroups based on the presence of inflammatory infiltrates. The subgroup of tumors consisting of 17 inflammatory lesions, resembled telangiectatic focal nodular hyperplasias, with frequent cytological abnormalities (P = 10−3), ductular reaction (P < 10−2), and dystrophic vessels (P = .02). In this classification, hepatocellular carcinoma associated with adenoma or borderline lesions between carcinoma and adenoma is found in 46% of the β‐catenin–mutated tumors whereas they are never observed in inflammatory lesions and are rarely found in HNF1α mutated tumors (P = .004). In conclusion, the molecular and pathological classification of hepatocellular adenomas permits the identification of strong genotype–phenotype correlations and suggests that adenomas with β‐catenin activation have a higher risk of malignant transformation. (HEPATOLOGY 2006;43:515–524.)

Prospective Study of the Long-Term Effects of Bariatric Surgery on Liver Injury in Patients Without Advanced Disease

BACKGROUND & AIMS Severe obesity is implicated in development of nonalcoholic fatty liver disease (NAFLD). Bariatric surgery induces weight loss and increases survival time of obese patients, but little is known about its effects on liver damage. We performed a 5-year prospective study to evaluate fibrosis and nonalcoholic steatosis (NASH) in severely obese patients after bariatric surgery. METHODS Bariatric surgery was performed on 381 patients. Clinical and biological data, along with liver biopsies, were collected before and at 1 and 5 years after surgery. RESULTS Five years after surgery, levels of fibrosis increased significantly, but 95.7% of patients maintained a fibrosis score <or= F1. The percentage of patients with steatosis decreased from 37.4% before surgery to 16%, the NAFLD score from 1.97 to 1, ballooning from 0.2 to 0.1. Inflammation remained unchanged. The percentage of patients with probable or definite NASH decreased significantly over 5 years, from 27.4% to 14.2%. The kinetics of insulin resistance (IR) paralleled that of steatosis and ballooning; the greatest improvements occurred within the first year and were sustained 5 years later. Steatosis and ballooning occurred more frequently in patients with a refractory IR profile. In multivariate analysis, the refractory IR profile independently predicted the persistence of steatosis and ballooning 5 years later. CONCLUSIONS Five years after bariatric surgery for severe obesity, almost all patients had low levels of NAFLD, whereas fibrosis slightly increased. Steatosis and ballooning were closely linked to IR; long-term effects could be predicted by early improvement in IR.

Weiss system revisited: a clinicopathologic and immunohistochemical study of 49 adrenocortical tumors.

The definitive diagnostic criteria for malignant adrenocortical tumors are distant metastasis and/or local invasion. The Weiss histopathologic system is the most commonly used method for assessing malignancy because of its simplicity and reliability. Unfortunately, its application remains subjective. This current retrospective study evaluated the Weiss system and assessed the value of MIB-1 labeling in the diagnosis of adrenocortical malignancy. Twenty-four malignant tumors with distant metastasis, gross local invasion, or recurrence were selected and matched on their functioning status to 25 benign tumors. Two independent observers delineated the Weiss criteria. An MIB-1 labeling index was determined. Presence of three or more Weiss microscopic criteria was related to malignancy (specificity 96%, sensitivity 100%), thus confirming the value of the Weiss system. Interobserver agreement for the Weiss system (total score) was excellent (r = 0.94). The lack of reliability for some Weiss criteria led us to propose a statistically modified system, based on the most reliable criteria (2.mitotic rate × 2.cytoplasm × abnormal mitoses × necrosis × capsular invasion) with a significant correlation with the Weiss system (r = 0.98). The MIB-1 labeling index was significantly higher in malignant tumors (p <0.0001). MIB1 could also help to differentiate malignant from benign adrenocortical tumors.

Galectin-4 and sulfatides in apical membrane trafficking in enterocyte-like cells

We have previously reported that 1-benzyl-2-acetamido-2-deoxy-α-d-galactopyranoside (GalNAcα-O-bn), an inhibitor of glycosylation, perturbed apical biosynthetic trafficking in polarized HT-29 cells suggesting an involvement of a lectin-based mechanism. Here, we have identified galectin-4 as one of the major components of detergent-resistant membranes (DRMs) isolated from HT-29 5M12 cells. Galectin-4 was also found in post-Golgi carrier vesicles. The functional role of galectin-4 in polarized trafficking in HT-29 5M12 cells was studied by using a retrovirus-mediated RNA interference. In galectin-4–depleted HT-29 5M12 cells apical membrane markers accumulated intracellularly. In contrast, basolateral membrane markers were not affected. Moreover, galectin-4 depletion altered the DRM association characteristics of apical proteins. Sulfatides with long chain-hydroxylated fatty acids, which were also enriched in DRMs, were identified as high-affinity ligands for galectin-4. Together, our data propose that interaction between galectin-4 and sulfatides plays a functional role in the clustering of lipid rafts for apical delivery.

Bariatric Surgery Reduces Features of Nonalcoholic Steatohepatitis in Morbidly Obese Patients

BACKGROUND & AIMS The effects of bariatric surgery in patients with nonalcoholic fatty liver disease (NASH) are not well established. We performed a prospective study to determine the biological and clinical effects of bariatric surgery in patients with NASH. METHODS From May 1994 through May 2013, one hundred and nine morbidly obese patients with biopsy-proven NASH underwent bariatric surgery at the University Hospital of Lille, France (the Lille Bariatric Cohort). Clinical, biological, and histologic data were collected before and 1 year after surgery. RESULTS One year after surgery, NASH had disappeared from 85% of the patients (95% confidence interval [CI]: 75.8%-92.2%). Compared with before surgery, patients had significant reductions in mean ± SD body mass index (BMI, from 49.3 ± 8.2 to 37.4 ± 7) and level of alanine aminotransferase (from 52.1 ± 25.7 IU/L to 25.1 ± 20 IU/L); mean levels of γ-glutamyltransferases were reduced from 51 IU/L before surgery (interquartile range [IQR], 34-87 IU/L) to 23 IU/L afterward (IQR, 14-33 IU/L) and mean insulin resistance index values were reduced from 3.6 ± 0.5 to 2.9 ± 0.5 (P < .01 for each comparison). NASH disappeared from a higher proportion of patients with mild NASH before surgery (94%) than severe NASH (70%) (P < .05) according to Brunt score. In histologic analysis, steatosis was detected in 60% of the tissue before surgery (IQR, 40%-80%) but only 10% 1 year after surgery (IQR, 2.5%-21.3%); the mean nonalcoholic fatty liver disease score was reduced from 5 (IQR, 4-5) to 1 (IQR, 1-2) (each P < .001). Hepatocellular ballooning was reduced in 84.2% of samples (n = 69; 95% CI: 74.4-91.3) and lobular inflammation in 67.1% (n = 55; 95% CI: 55.8-77.1). According to Metavir scores, fibrosis was reduced in 33.8% of patients (95% CI: 23.6%-45.2%). Patients whose NASH persisted 1 year after surgery (n = 12) had lost significantly less weight (change in BMI, 9.1 ± 1.5) than those without NASH (change in BMI, 12.3 ± 0.6) (P = .005). Patients who underwent laparoscopic gastric banding lost less weight (change in BMI, 6.4 ± 0.7) than those who underwent gastric bypass (change in BMI, 14.0 ± 0.5) (P < .0001), and a higher proportion had persistent NASH (30.4% vs 7.6% of those with gastric bypass; P = .015). CONCLUSIONS Bariatric surgery induced the disappearance of NASH from nearly 85% of patients and reduced the pathologic features of the disease after 1 year of follow-up. It could be a therapeutic option for appropriate morbidly obese patients with NASH who do not respond to lifestyle modifications. More studies are needed to determine the long-term effects of bariatric surgery in morbidly obese patients with NASH.

Signet ring cell histology is an independent predictor of poor prognosis in gastric adenocarcinoma regardless of tumoral clinical presentation.

Objective:To test the hypothesis that signet ring cell (SRC) histology has a negative prognostic value in patients with gastric adenocarcinoma (ADC). Summary Background Data:In western countries, gastric ADC with SRC often occurs after the disease has advanced. Consequently, the prognosis of SRC is generally regarded as poor, although survival studies comparing SRC and non-SRC have yielded inconsistent results. Methods:An intent to treat analysis was performed among 215 patients with gastric ADC scheduled for surgical resection from 1996 to 2007. Of these, 180 patients underwent the resection and 35 were not resected due to diffuse metastatic illness. From 59 resected patients with SRC (SRC group), control non-SRC resected patients matched by age, gender, American Society of Anaesthesiologists (ASA) classification, tumoral location, and pTNM stage were randomly selected by computer (non-SRC group: n = 100) during the same study period. Results:The overall median survival was 21 months, which was significantly higher in resected compared to non-resected patients (31 vs. 5 months, P < 0.001). In non-resected patients, SRC histological subtype was associated with higher rates of diffuse peritoneal carcinomatosis (90.1% vs. 62.5%, P = 0.053) and neoplastic ascitis (63.6% vs. 34.7%, P = 0.059) and poorer median survival (5 vs. 7 months, P = 0.062). For resected patients, the 2 groups (SRC and non-SRC) were comparable regarding matching variables, demographic variables, and postoperative course. The median survival was significantly lower for SRC patients (21 vs. 44 months, P = 0.004). SRC resected patients exhibited higher rates of localized peritoneal carcinomatosis (P = 0.013) and lymph node involvement (P < 0.001) at diagnosis, lower R0 resection rate (P = 0.019) and earlier tumor relapse (P = 0.009), which was generally in a peritoneal carcinomatosis form (P = 0.011). By multivariate analysis, we concluded that SRC histology was independently associated with a dismal prognosis after adjustment on confounding variables (hazard ratio = 1.5, 95% confidence interval 1.1–2.0, P = 0.004). The prognostic role of SRC was maintained after exclusion of patients with advanced stage at initial diagnosis such as localized peritoneal carcinomatosis or lymph node invasion. Conclusions:This study is currently the best evidence showing that SRC is a major and independent predictor of poor prognosis due to specific characteristics such as more infiltrating tumors showing affinity for lymphatic tissue accompanied by a higher rate of peritoneal carcinomatosis. Our results suggest the need for a specific therapeutic strategy for such tumors.

A Histologic Scoring System for Prognosis of Patients With Alcoholic Hepatitis

BACKGROUND & AIMS There is no histologic classification system to determine prognoses of patients with alcoholic hepatitis (AH). We identified histologic features associated with disease severity and created a histologic scoring system to predict short-term (90-day) mortality. METHODS We analyzed data from 121 patients admitted to the Liver Unit (Hospital Clinic, Barcelona, Spain) from January 2000 to January 2008 with features of AH and developed a histologic scoring system to determine the risk of death using logistic regression. The system was tested and updated in a test set of 96 patients from 5 academic centers in the United States and Europe, and a semiquantitative scoring system called the Alcoholic Hepatitis Histologic Score (AHHS) was developed. The system was validated in an independent set of 109 patients. Interobserver agreement was evaluated by weighted κ statistical analysis. RESULTS The degree of fibrosis, degree of neutrophil infiltration, type of bilirubinostasis, and presence of megamitochondria were independently associated with 90-day mortality. We used these 4 parameters to develop the AHHS to identify patients with a low (0-3 points), moderate (4-5 points), or high (6-9 points) risk of death within 90 days (3%, 19%, and 51%, respectively; P < .0001). The AHHS estimated 90-day mortality in the training and test sets with an area under the receiver operating characteristic value of 0.77 (95% confidence interval, 0.71-0.83). Interrater agreement values were 0.65 for fibrosis, 0.86 for bilirubinostasis, 0.60 for neutrophil infiltration, and 0.46 for megamitochondria. Interestingly, the type of bilirubinostasis predicted the development of bacterial infections. CONCLUSIONS We identified histologic features associated with the severity of AH and developed a patient classification system that might be used in clinical decision making.

Mucin gene expression in intestinal epithelial cells in Crohn's disease.

BACKGROUND Crohns disease (CD) is a chronic relapsing inflammatory bowel disease of unknown origin. It is characterised by chronic mucosal ulcerations which affect any part of the intestine but most commonly are found in the ileum and proximal colon. AIMS Studies were undertaken to provide information regarding cell specific expression of mucin genes in the ileum of patients with CD. PATIENTS AND METHODS Expression of mucin genes was analysed in the ileal mucosa of patients with CD and controls by in situ hybridisation and immunohistochemistry. RESULTS In healthy ileal mucosa, patients with CD showed a pattern identical to normal controls with main expression of MUC2 andMUC3, lesser expression ofMUC1 and MUC4, and no expression of MUC5AC,MUC5B, MUC6, orMUC7. In the involved mucosa, the pattern was somewhat comparable although heterogeneous to that observed in healthy ileal mucosa. Importantly, a particular mucin gene expression pattern was observed in ileal mucosa close to the ulcer margins in ulcer associated cell lineage, with the appearance ofMUC5AC and MUC6mRNAs and peptides, which are normally restricted to the stomach (MUC5AC and MUC6) and duodenum (MUC6), and disappearance ofMUC2. CONCLUSIONS Our results suggest that gel forming mucins (more particularly MUC5AC and MUC6) may have a role in epithelial wound healing after mucosal injury in inflammatory bowel diseases in addition to mucosal protection.

CD30 and CD117 (c-kit) Used in Combination Are Useful for Distinguishing Embryonal Carcinoma from Seminoma

Germ-cell tumors are the most common malignant neoplasms of the testis. Seminomatous and non-seminomatous tumors must be differentiated because the treatment and the prognosis are different. In light microscopic examination, seminoma may sometimes be difficult to distinguish from the solid pattern of embryonal carcinoma (EC). Although studies have shown that CD30 was a good marker of embryonal carcinoma and that c-kit was regularly expressed in seminoma, none has described the value of CD30 and CD117 (c-kit) in combination for the differential diagnosis between EC and seminoma. We selected 25 pure seminomas, seven pure ECs, and seven mixed germ-cell tumors composed of seminoma and EC from our archives and studied their immunoreactivity for CD30 and CD117. We observed that 27/35 seminomas were CD117+/CD30-; none of the seminoma was CD117-/CD30+. Conversely, 11/14 ECs were CD30+/CD117- and none was CD30-/CD117+. Our findings suggest that CD117 and CD30 immunohistochemistry used in combination represents a valuable tool for distinguishing seminoma from EC.

Galectin-4-Regulated Delivery of Glycoproteins to the Brush Border Membrane of Enterocyte-Like Cells

We have previously reported that silencing of galectin‐4 expression in polarized HT‐29 cells perturbed apical biosynthetic trafficking and resulted in a phenotype similar to the inhibitor of glycosylation, 1‐benzyl‐2‐acetamido‐2‐deoxy‐β‐d‐galactopyranoside (GalNAcα‐O‐bn). We now present evidence of a lipid raft‐based galectin‐4‐dependent mechanism of apical delivery of glycoproteins in these cells. First, galectin‐4 recruits the apical glycoproteins in detergent‐resistant membranes (DRMs) because these glycoproteins were depleted in DRMs isolated from galectin‐4‐knockdown (KD) HT‐29 5M12 cells. DRM‐associated glycoproteins were identified as ligands for galectin‐4. Structural analysis showed that DRMs were markedly enriched in a series of complex N‐glycans in comparison to detergent‐soluble membranes. Second, in galectin‐4‐KD cells, the apical glycoproteins still exit the Golgi but accumulated inside the cells, showing that their recruitment within lipid rafts and their apical trafficking required the delivery of galectin‐4 at a post‐Golgi level. This lectin that is synthesized on free cytoplasmic ribosomes is externalized from HT‐29 cells mostly in the apical medium and follows an apical endocytic–recycling pathway that is required for the apical biosynthetic pathway. Together, our data show that the pattern of N‐glycosylation of glycoproteins serves as a recognition signal for endocytosed galectin‐4, which drives the raft‐dependent apical pathway of glycoproteins in enterocyte‐like HT‐29 cells.