Extracellular Matrix Proteome Remodeling in Human Glioblastoma and Medulloblastoma.

Medulloblastomas (MBs) and glioblastomas (GBMs) are high-incidence central nervous system tumors. Different origin sites and changes in the tissue microenvironment have been associated with the onset and progression. Here, we describe differences between the extracellular matrix (ECM) signatures of these tumors. We compared the proteomic profiles of MB and GBM decellularized tumor samples between each other and their normal decellularized brain site counterparts. Our analysis revealed that 19, 28, and 11 ECM proteins were differentially expressed in MBs, GBMs, and in both MBs and GBMs, respectively. Next, we validated key findings by using a protein tissue array with 53 MB and 55 GBM cases and evaluated the clinical relevance of the identified differentially expressed proteins through their analysis on publicly available datasets, 763 MB samples from the GSE50161 and GSE85217 studies, and 115 GBM samples from RNAseq-TCGA. We report a shift toward a denser fibrillary ECM as well as a clear alteration in the glycoprotein signature, which influences the tumor pathophysiology. MS data have been submitted to the PRIDE repository, project accession: PXD023350.

A phenotypical map of disseminated hepatocellular carcinoma suggests clonal constraints in metastatic sites.

AIMS: Access to tissue in patients with hepatocellular carcinoma (HCC) is limited compared to other malignancies, particularly at advanced stages. This has precluded a thorough characterisation of molecular drivers of HCC dissemination, particularly in relation to distant metastases. Biomarker assessment is restricted to early stages, and paired primary-metastatic comparisons between samples from the same patient are difficult. METHODS AND RESULTS: We report the evaluation of 88 patients with HCC who underwent autopsy, including multiregional sampling of primary and metastatic sites totalling 230 nodules analysed. The study included morphological assessment, immunohistochemistry and mutation status of the TERT promoter, the most frequently mutated gene in HCC. We confirm a strong predilection of HCC for lung dissemination, including subclinical micrometastases (unrecognised during imaging and macroscopic examinations) in 30% of patients with disseminated disease. Size of dominant tumour nodule; multinodularity; macrovascular invasion; high histological, nuclear and architectural grades; and cellular crowding were associated with the presence of extrahepatic metastasis. Among the immunohistochemistry markers tested, metastatic nodules had significantly higher K19 and EpCAM expression than primary liver tumours. Morphological and immunohistochemical features showed that metastatic HCC could be traced back to the primary tumour, sometimes to a specific hepatic nodule. CONCLUSIONS: This study suggests limited heterogeneity in metastatic sites compared to primary tumour sites.

Expression of LIN28 and its regulatory microRNAs in adult adrenocortical cancer.

OBJECTIVE: LIN28 control cells reprogramming and pluripotency mainly through miRNA regulation and has been overexpressed in many advanced cancers. In this study, we evaluated the prognostic role of LIN28 and its regulatory miRNAs in a large cohort of adrenocortical tumours (ACTs). PATIENTS AND METHODS: LIN28 protein expression was assessed in 266 adults ACTs (78 adenomas and 188 carcinomas) from Brazil and Germany. LIN28A and LIN28B gene expression was analysed in 59 ACTs (31 adenomas and 28 carcinomas) and copy number variation in 39 ACTs. In addition, we determined the expression of let-7 family, mir-9, mir-30 and mir-125 in 28 carcinomas. RESULTS: LIN28A gene was overexpressed in aggressive ACCs when compared with adenomas and nonaggressive ACCs, but no LIN28A copy number variation was found in ACTs. Unexpectedly, weak LIN28 protein expression was significantly associated with reduced disease-free survival in ACC patients (P = 0·01), but for overall survival only a trend was detectable (P = 0·117). In the multivariate analysis, only Ki67 index ≥10% (HR 4·6, P = 0·000) and weak LIN28 protein expression (HR 2·0, P = 0·03) were independent predictors of recurrence in ACC patients. Interestingly, mir-9 expression, a negative LIN28A/B regulator, was significantly higher in aggressive than in nonaggressive ACCs [2076 (from 36 to 9307) vs 133·4 (from 2·4 to 5193); P = 0·011] and was highly associated with reduced overall (P = 0·01) and disease-free survival (P = 0·01). However, mir-9 prognostic role should be further evaluated in a larger cohort. CONCLUSION: Weak LIN28 protein expression was associated with recurrence in ACCs. Additionally, overexpression of mir-9, a negative LIN28A regulator, was associated with poor outcome.

Dermcidin exerts its oncogenic effects in breast cancer via modulation of ERBB signaling.

BACKGROUND: We previously identified dermicidin (DCD), which encodes a growth and survival factor, as a gene amplified and overexpressed in a subset of breast tumors. Patients with DCD-positive breast cancer have worse prognostic features. We therefore searched for specific molecular signatures in DCD-positive breast carcinomas from patients and representative cell lines. METHODS: DCD expression was evaluated by qRT-PCR, immunohistochemical and immunoblot assays in normal and neoplastic tissues and cell lines. To investigate the role of DCD in breast tumorigenesis, we analyzed the consequences of its downregulation in human breast cancer cell lines using three specific shRNA lentiviral vectors. Genes up- and down-regulated by DCD were identified using Affymetrix microarray and analyzed by MetaCore Platform. RESULTS: We identified DCD splice variant (DCD-SV) that is co-expressed with DCD in primary invasive breast carcinomas and in other tissue types and cell lines. DCD expression in breast tumors from patients with clinical follow up data correlated with high histological grade, HER2 amplification and luminal subtype. We found that loss of DCD expression led to reduced cell proliferation, resistance to apoptosis, and suppressed tumorigenesis in immunodeficient mice. Network analysis of gene expression data revealed perturbed ERBB signaling following DCD shRNA expression including changes in the expression of ERBB receptors and their ligands. CONCLUSIONS: These findings imply that DCD promotes breast tumorigenesis via modulation of ERBB signaling pathways. As ERBB signaling is also important for neural survival, HER2+ breast tumors may highjack DCD's neural survival-promoting functions to promote tumorigenesis.

Angiogenesis and expression of PDGF-C, VEGF, CD105 and HIF-1α in human glioblastoma.

Glioblastoma (GBM), the most frequent and aggressive brain tumor, is characterized by marked angiogenesis directly related to invasiveness and poor prognosis. Hypoxia is considered to be an important stimulus for angiogenesis by inducing hypoxia-inducible factor 1-alpha (HIF-1α) overexpression that activates platelet-derived growth factor (PDGF) and VEGF. The aim of this study is to analyze the expression of PDGF-C, VEGF in endothelial and tumor cells of GBM and their relation to HIF-1α expression. Two hundred and eight GBM cases were studied by tissue microarray immunohistochemical preparation. Expression of HIF-1α, VEGF and PDGF-C was observed in 184 (88.5%), 131 (63%) and 160 (76.9%) tumor cases, respectively. The numbers of vessels were quantified by CD34, PDGF-C, VEGF and CD105 staining, and were in median 20, 16, 5 and 6, respectively. The GBMs that showed positive or negative expression for HIF-1α showed a median vascular density of 30 and 14, respectively, for CD34 (P < 0.015). Positive expression for HIF-1α was correlated with VEGF and PDGF-C expression in tumors (P < 0.001). There was a significant correlation between VEGF and PDGF-C expression in the cytoplasm of GBM tumor cells (P < 0.0001). We showed that VEGF expression in tumor cells was correlated with its expression in blood vessels (P < 0.0001). Endothelial cells with PDGF-C and VEGF positive expression were also positive for CD105 and their nuclei for Ki-67, confirming the neoangiogenic and proliferative influence of VEGF and PDGF-C. VEGF nuclear staining in tumor cells (P = 0.002) as well as nuclear staining for HIF-1α and VEGF (P = 0.005) correlated with survival. In summary, our present findings of the concomitant upregulation of PDGF-C with VEGF in GBM tumor cells and vessels further reinforce the benefit of using combined anti-angiogenic approaches to potentially improve the therapeutic response for GBM.

Age-related dysfunction of the lacrimal gland and oxidative stress: evidence from the Cu,Zn-superoxide dismutase-1 (Sod1) knockout mice.

An imbalance between free radical generation and radical scavenging antioxidant systems results in oxidative stress, which has been associated with cell injury observed in many age-related diseases. The superoxide dismutase (SOD) family is a major antioxidant system, and deficiency of Cu,Zn-superoxide dismutase-1 (Sod1) in mice leads to many different phenotypes that resemble accelerated aging. In this study we examined the morphologic features and the secretory functions of the lacrimal glands in Sod1(-/-) mice. Lacrimal glands showed atrophy of acinar units; fibrosis; infiltration with CD4(+) T cells, monocytes, and neutrophils; increased staining with both 4-hydroxy-2-nonenal and 8-hydroxy-2'-deoxyguanosine; increases in apoptotic cells; and the presence of the epithelial-mesenchymal transition in senescent Sod1(-/-) mice. Electron microscopy findings revealed evidence of epithelial-mesenchymal transition, presence of swollen and degenerated mitochondria, and the presence of apoptotic cell death in the lacrimal glands of senescent Sod1(-/-) mice. These alterations were also associated with the accumulation of secretory vesicles in acinar epithelial cells, decreased production of both stimulated and nonstimulated tears, and a decline in total protein secretion from the lacrimal glands. Our results suggest that Sod1(-/-) mice may be a good model system in which to study the mechanism of reactive oxygen species-mediated lacrimal gland alterations.

Impact of a cell cycle and an extracellular matrix remodeling transcriptional signature on tumor progression and correlation with EZH2 expression in meningioma.

OBJECTIVE: The authors searched for genetic and transcriptional signatures associated with tumor progression and recurrence in their cohort of patients with meningiomas, combining the analysis of targeted exome, NF2-LOH, transcriptome, and protein expressions. METHODS: The authors included 91 patients who underwent resection of intracranial meningioma at their institution between June 2000 and November 2007. The search of somatic mutations was performed by Next Generation Sequencing through a customized panel and multiplex ligation-dependent probe amplification for NF2 loss of heterozygosity. The transcriptomic profile was analyzed by QuantSeq 3' mRNA-Seq. The differentially expressed genes of interest were validated at the protein level analysis by immunohistochemistry. RESULTS: The transcriptomic analysis identified an upregulated set of genes related to metabolism and cell cycle and downregulated genes related to immune response and extracellular matrix remodeling in grade 2 (atypical) meningiomas, with a significant difference in recurrent compared with nonrecurrent cases. EZH2 nuclear positivity associated with grade 2, particularly with recurrent tumors and EZH2 gene expression level, correlated positively with the expression of genes related to cell cycle and negatively to genes related to immune response and regulation of cell motility. CONCLUSIONS: The authors identified modules of dysregulated genes in grade 2 meningiomas related to the activation of oxidative metabolism, cell division, cell motility due to extracellular remodeling, and immune evasion that were predictive of survival and exhibited significant correlations with EZH2 expression.

ß-Catenin-Driven Differentiation Is a Tissue-Specific Epigenetic Vulnerability in Adrenal Cancer.

Adrenocortical carcinoma (ACC) is a rare cancer in which tissue-specific differentiation is paradoxically associated with dismal outcomes. The differentiated ACC subtype CIMP-high is prevalent, incurable, and routinely fatal. CIMP-high ACC possess abnormal DNA methylation and frequent ß-catenin-activating mutations. Here, we demonstrated that ACC differentiation is maintained by a balance between nuclear, tissue-specific ß-catenin-containing complexes, and the epigenome. On chromatin, ß-catenin bound master adrenal transcription factor SF1 and hijacked the adrenocortical super-enhancer landscape to maintain differentiation in CIMP-high ACC; off chromatin, ß-catenin bound histone methyltransferase EZH2. SF1/ß-catenin and EZH2/ß-catenin complexes present in normal adrenals persisted through all phases of ACC evolution. Pharmacologic EZH2 inhibition in CIMP-high ACC expelled SF1/ß-catenin from chromatin and favored EZH2/ß-catenin assembly, erasing differentiation and restraining cancer growth in vitro and in vivo. These studies illustrate how tissue-specific programs shape oncogene selection, surreptitiously encoding targetable therapeutic vulnerabilities. SIGNIFICANCE: Oncogenic ß-catenin can use tissue-specific partners to regulate cellular differentiation programs that can be reversed by epigenetic therapies, identifying epigenetic control of differentiation as a viable target for ß-catenin-driven cancers.

IMMUNOHISTOCHEMICAL ASSESSMENT OF LYMPHATIC VESSELS IN HUMAN LIVERS WITH CHRONIC HEPATITIS C - RELATION TO HISTOLOGICAL VARIABLES.

BACKGROUND: Viral hepatitis C is a significant public health challenge. The disease may remain clinically silent in both acute and chronic forms, and chronic infections may progress to advanced disease such as cirrhosis and hepatocellular carcinoma, requiring costly treatment, compromising the patient's quality of life and even leading to death. For this reason, it is one of the most frequent indications for liver transplantation. Although treatment with direct-acting antivirals represents remarkable progress, many patients are still infected and even those who cleared the viral infection must be followed due to their previous hepatic lesions, especially regarding the disturbances of lobular architecture and the sanguineal and lymphatic vessels. OBJECTIVE: To assess immunohistochemical aspects of lymphatic sprouts and mature lymphatic vascularity with histological variables of liver injury attributable to hepatitis C virus (HCV) and fatty disease. METHODS: The present study included 72 liver biopsies of cases with chronic hepatitis C. Morphologic changes reflecting "staging" and "activity" were analyzed. Immunohistochemical reactions were performed with monoclonal antibody D2-40 anti-podoplanin. Major histological variables were also semiquantified so as to enable the search for possible associations among histological and Immunohistochemical criteria, as well as with genotypes 1 and 3 of HCV. RESULTS: Histological findings showed that the different degrees of strutural changes were well represented in this casuistic. Intralobular/parenchymal necro-inflammatory activity was predominantly mild to moderate. Most cases did not show major evidences of fatty disease, which was found significantly higher in cases infected with HCV genotype 3. The amount of portal lymphatic sprouts increased along with the progression of structural changes, maximal at cirrhosis. Portal lymphatic sprouts as well as portal mature lymphatic vessels also showed an increase parallel to the increase in the degree of portal/septal inflammatory infiltrate. In the present study, no significant association was found between the proportion of portal lymphatic sprouts or portal mature lymphatic vessels and the degree of periportal/periseptal activity. No significant relations were detected between lymphatic sprouts/mature vessels and periportal or parenchymal inflammatory activity, nor with infections due to HCV genotype 1 or 3. CONCLUSION: Visualization and semiquantitation of sprouts and mature lymphatic vessels were clearly yielded by Immunohistochemical staining with monoclonal antibody D2-40. The amount of lymphatics was increased along fibrogenic process, significantly related to progression of liver disease and maximal at cirrhosis. No significant relations were detected with necro-inflammatory activity at interface or in the parenchyma.

Combined use of immunohistochemical markers of basal and luminal subtypes in urothelial carcinoma of the bladder: Association with clinicopathological features and outcomes.

OBJECTIVES: Whole genome expression profiles allow the stratification of bladder urothelial carcinoma into basal and luminal subtypes which differ in histological patterns and clinical behavior. Morpho-molecular studies have resulted in the discovery of immunohistochemical markers that might enable discrimination between these two major phenotypes of urothelial carcinoma. METHODS: We used two combinations of immunohistochemical markers, i.e., cytokeratin (CK) 5 with CK20 and CK5 with GATA3, to distinguish subtypes, and investigated their association with clinicopathological features, presence of histological variants, and outcomes. Upon searching for tumor heterogeneity, we compared the findings of primary tumors with their matched lymph node metastases. We collected data from 183 patients who underwent cystectomy for high-grade muscle-invasive urothelial carcinoma, and representative areas from the tumors and from 76 lymph node metastasis were organized in tissue microarrays. RESULTS: Basal immunohistochemical subtype (CK5 positive and CK20 negative, or CK5 positive and GATA3 negative) was associated with the squamous variant. The luminal immunohistochemical subtype (CK5 negative and CK20 positive, or CK5 negative and GATA3 positive) was associated with micropapillary and plasmacytoid variants. Remarkably, only moderate agreement was found between the immunohistochemical subtypes identified in bladder tumors and their lymph node metastasis. No significant difference in survival was observed when using either combination of the markers. CONCLUSION: This study demonstrates that these three routinely used immunohistochemical markers could be used to stratify urothelial carcinomas of the bladder into basal and luminal subtypes, which are associated with several differences in clinicopathological features.

Clinical Impact of Pathological Features Including the Ki-67 Labeling Index on Diagnosis and Prognosis of Adult and Pediatric Adrenocortical Tumors.

Adrenocortical tumors (ACT) in the adult and pediatric population are generally considered distinct entities due to differences in molecular events related to tumorigenesis, clinical presentation, and outcome. Furthermore, pathological criteria used for diagnosis and prognostication of ACT in adults are usually inadequate for predicting the biological behavior of ACT in children. Here, we analyzed 146 adult and 44 pediatric (< 15y/o) ACT with long-term clinical follow-up and furthered current evidence on the clinical and pathological differences between pediatric and adult tumors. Predilection for female over male gender was observed in both cohorts, but more so in adults (84% vs. 61%, p = 0.003). Cushing syndrome was more frequent in adults (p < 0.001), whereas virilization, either isolated (p < 0.001) or combined to Cushing (p = 0.047), was more common in children. The Ki67 labelling index (LI) of pediatric adenomas and carcinomas was much higher than their corresponding tumors in adults (p < 0.001). Despite these differences, pathological analyses including the evaluation of Ki67 greatly improved patient prognostication in both age cohorts. Indeed, increased Weiss scores and Ki67 indexes correlated with poor overall- and disease-free survival in adult patients with carcinoma. Among the proliferative indexes tested, Ki67 LI ≥ 10% showed the highest hazard ratio (HR) for recurrence and the Ki67 LI ≥ 3% showed the highest HR for survival. In pediatric tumors, the Wieneke score (p < 0.001) and the Ki67 LI (p < 0.001) showed high accuracy for predicting biological behavior, and increased scores/indexes correlated with worse overall and disease-free survival. In this age cohort, Ki67 LI < 10% was able to rule out malignant behavior, whereas Ki67 LI ≥ 15% may be used to predict the patients with higher risks of recurrence and/or poor outcome.

iASPP: a novel protein involved in pituitary tumorigenesis?

Pituitary tumors can be morphologically classified as microadenomas (diameter<1 cm) or macroadenomas (>1 cm), which can be enclosed, invasive and/or expansive. Functionally, they are classified as secreting tumors and clinically non-secreting or 'non-functioning' tumors. Several molecular mechanisms have been studied acting in uncontrolled cell proliferation and the acquisition of resistance to apoptosis. A potential mechanism related to apoptosis control has been found following the isolation and characterization of the ASPP proteins family. All these proteins share sequence similarities in their C-termini, which contains their signature sequences of Ankyrin repeats, SH3 domain and proline-rich region. Recent investigations reported that the expression of iASPP mRNA and protein was increased in non-transformed cells induced to undergo apoptosis and inhibition of iASPP expression in these cells by siRNA reduced apoptosis. Thus, modulation of iASPP expression seems to be an integral part of the apoptotic response. The ASPP proteins family binds to proteins that are key players in controlling apoptosis (P53 and NFkappaB p65 subunit). It has been speculated that the iASPP protein product induces apoptosis by blocking NFkappaB or inhibits apoptosis by blocking P53. By either mechanism, the gene could influence the survival of precancerous lesions.

Immunohistochemical Assessment of the Expression of Biliary Transportation Proteins MRP2 and MRP3 in Hepatocellular Carcinoma and in Cholangiocarcinoma.

Multidrug resistance-associated protein 2 (MRP2) is a multi-specific organic anion transporter predominantly expressed in the canalicular membrane of hepatocytes, epithelial cells from gallbladder and apical membranes of proximal tubular kidney epithelium whereas multidrug resistance-associated protein 3 (MRP3) is present in the basolateral membrane of hepatocytes and cholangiocytes. This study aims to detect the expression of these transporters in hepatocellular carcinoma (HCC) and in cholangiocarcinoma (CC), searching for evidences for future studies on differential diagnosis and on clinical essays. The immunohistochemical reactivity (IHC) of these transporters was assessed in tissue microarrays of 80 HCC and 56 CC cases using monoclonal antibodies and compared with anatomopathological (AP) variables. The positivity of MRP2 was observed in 92.3% of HCC and in 96.3% of CC. The detection of high MRP2 expression in HCC was not significantly different (p > 0.05) according to the size, number of nodules architectural pattern and growth pattern of HCC and CC. Regarding histological grades, 22/22 well moderately differentiated HCC versus 50/56 poorly differentiated HCC were positive for MRP2. A trend for lower expression in poor differentiation HCC was found. And 50/50 well/moderately differentiated CC versus 2/4 poorly/undifferentiated CC were positive for MRP2. This result showed a reduced expression (p = 0,0004) in poorly differentiated CC. MRP3 positivity was observed in 18.8% of HCC and was not significantly different according to AP parameters. MRP3 was expressed in 44.5% CC, with a trend for lower expression in less differentiated CC and significantly lower rates in the ductular histological subtype (p = 0.023). The high expression of MRP2 in HCC and in CC is conserved regardless most of the anatomopathological parameters, except for a trend of lower expression in less differentiated HCC and CC. The observation of lower MRP3 expression in less differentiated CC and, especially, in the histological subtype with expression of hepatic progenitor cell phenotypes leads to future opportunities to evaluate the expression of this marker in cholangiocarcinomas.

Post-transplant recurrent hepatitis C: immunohistochemical detection of hepatitis C virus core antigen and possible pathogenic implications.

INTRODUCTION: The mechanisms by which severe cholestatic hepatitis develops after liver transplantation are not fully understood. Reports on immunohistochemical distribution of hepatitis C virus (HCV) antigens are still scarce, but recently, HCV immunostaining was suggested for early diagnosis of cholestatic forms of recurrent hepatitis C in liver grafts. After purification, Rb246 pab anticore (aa1-68) yielded specific, granular cytoplasmic staining in hepatocytes. Signal amplification through the Envision-Alkaline Phosphatase System avoided endogenous biotin and peroxidase. AIMS/METHODS: Rb246 was applied to liver samples of explants of 12 transplant recipients, six with the most severe form of post-transplantation recurrence, severe cholestatic hepatitis (group 1) and six with mild recurrence (group 2). We also assessed immuno-reactivity at two time-points post-transplantation (median 4 and 22 months) in both groups. HCV-core Ag was semiquantified from 0 to 3+ in each time point. Serum HCV-RNA was also measured on the different time points by branched DNA. RESULTS: In the early post-transplant time point, one patient had a mild staining (1+), two patients had a moderate staining (2+) and the other three had no staining in group 1, compared with five patients with no staining (0) and one patient with mild staining (1+) in group 2. Late post-transplant liver samples were available in nine patients, and two out of four samples in group 1 showed a mild staining, compared with no staining patients in five patients in group 2. Strikingly, on the explant samples, HCV immunostaining was strongly positive in group 1, and mildly positive in group 2. Two out of five samples showed 3+ staining, and three samples showed 2+ staining in group 1; two out of five samples showed no staining, two samples showed 1+ staining and one sample showed 2+ staining in group 2. Serum HCV-RNA was significantly higher in group 1, on both time-points post-transplantation. HCV-core Ag was not directly associated with serum HCV-RNA on the different time points. CONCLUSION: These preliminary results suggest that strong HCV immunostaining in the explant is predictive of more severe disease recurrence.

Oncogenic mutations in KEAP1 disturbing inhibitory Nrf2-Keap1 interaction: Activation of antioxidative pathway in papillary thyroid carcinoma.

BACKGROUND: Nuclear factor erythroid 2-like 2 (NFE2L2) encodes Nrf2, transcription factor of antioxidative genes. In the presence of reactive oxygen species, Keap1 (Kelch-ECH-associating protein-1) inhibitor complex undergoes conformational changes disrupting Keap1-Nrf2 binding and Nrf2 translocates into nucleus. We evaluated the presence of mutations in NFE2L2 and KEAP1 in papillary thyroid carcinomas (PTCs) and correlated them with clinical presentation. METHODS: Coding regions of NFE2L2 and KEAP1 were sequenced in 131 patients with PTC. Clinical and histopathological features were analyzed. Immunohistochemical analysis of Nrf2 expression was performed in mutated carcinomas. RESULTS: Although no mutations were found in NFE2L2, missense mutations in KEAP1 were observed in 6 patients with PTC (4.6%). Immunohistochemistry showed increased Nrf2 expression in nuclei of all mutated carcinomas, which presented poor prognostic features in histopathology. CONCLUSION: We identified mutations in KEAP1 associated with Nrf2 overexpression in PTC. Mutations favored disruption of inhibitory interaction Nrf2-Keap1 to enable increased antioxidant Nrf2 activity, possibly with prognostic consequences.

Modulation of hepatic microsomal triglyceride transfer protein (MTP) induced by S-nitroso-N-acetylcysteine in ob/ob mice.

We evaluated the effects of a potent NO donor, S-nitroso-N-acetylcysteine (SNAC), on microsomal triglyceride transfer protein (MTP) expression in ob/ob mice. NAFLD was induced in male ob/ob mice using a methionine-choline deficient diet (MCD) concomitantly with oral SNAC fed solution (n=5) or vehicle (control; n=5) by gavage daily for 4 weeks. Livers were collected for histology and for assessing MTP by RT-qPCR, Western blot, immunohistochemistry and immunogold electron microscopy analyses. Histological analysis showed diffuse macro and microvesicular steatosis, moderate hepatocellular ballooning and moderate inflammatory infiltrate in ob/ob mice fed the MCD diet. With SNAC, mice showed a marked reduction in liver steatosis (p<0.01), in parenchymal inflammation (p=0.02) and in MTP protein immunoexpression in zone III (p=0.05). Moreover, SNAC caused reduction of MTP protein in Western blot analysis (p<0.05). In contrast, MTP mRNA content was significantly higher (p<0.05) in mice receiving SNAC. Immuno-electron microscopy showed MTP localized in the rough endoplasmic reticulum of hepatocytes in both treated and untreated groups. However with SNAC treatment, MTP was also observed surrounding fat globules. Histological improvement mediated by a nitric oxide donor is associated with significantly altered expression and distribution of MTP in this animal model of fatty liver disease. Further studies are in progress to examine possible mechanisms and to develop SNAC as a possible therapy for human fatty liver disease.

Immunohistochemical assessment of lymphatic vessels in human livers with chronic hepatitis C ­ relation to histological variables

Background Viral hepatitis C is a significant public health challenge. The disease may remain clinically silent in both acute and chronic forms, and chronic infections may progress to advanced disease such as cirrhosis and hepatocellular carcinoma, requiring costly treatment, compromising the patient's quality of life and even leading to death. For this reason, it is one of the most frequent indications for liver transplantation. Although treatment with direct-acting antivirals represents remarkable progress, many patients are still infected and even those who cleared the viral infection must be followed due to their previous hepatic lesions, especially regarding the disturbances of lobular architecture and the sanguineal and lymphatic vessels. Objective To assess immunohistochemical aspects of lymphatic sprouts and mature lymphatic vascularity with histological variables of liver injury attributable to hepatitis C virus (HCV) and fatty disease. Methods The present study included 72 liver biopsies of cases with chronic hepatitis C. Morphologic changes reflecting "staging" and "activity" were analyzed. Immunohistochemical reactions were performed with monoclonal antibody D2-40 anti-podoplanin. Major histological variables were also semiquantified so as to enable the search for possible associations among histological and Immunohistochemical criteria, as well as with genotypes 1 and 3 of HCV. Results Histological findings showed that the different degrees of strutural changes were well represented in this casuistic. Intralobular/parenchymal necro-inflammatory activity was predominantly mild to moderate. Most cases did not show major evidences of fatty disease, which was found significantly higher in cases infected with HCV genotype 3. The amount of portal lymphatic sprouts increased along with the progression of structural changes, maximal at cirrhosis. Portal lymphatic sprouts as well as portal mature lymphatic vessels also showed an increase parallel to the increase in the degree of portal/septal inflammatory infiltrate. In the present study, no significant association was found between the proportion of portal lymphatic sprouts or portal mature lymphatic vessels and the degree of periportal/periseptal activity. No significant relations were detected between lymphatic sprouts/mature vessels and periportal or parenchymal inflammatory activity, nor with infections due to HCV genotype 1 or 3. Conclusion Visualization and semiquantitation of sprouts and mature lymphatic vessels were clearly yielded by Immunohistochemical staining with monoclonal antibody D2-40. The amount of lymphatics was increased along fibrogenic process, significantly related to progression of liver disease and maximal at cirrhosis. No significant relations were detected with necro-inflammatory activity at interface or in the parenchyma.

Avaliação imunohistoquímica dos vasos linfáticos em fígados humanos com hepatite crônica C - relação com variáveis histológicas / Immunohistochemical assessment of lymphatic vessels in human livers with chronic hepatitis c - relation to histological variables

ABSTRACT Background Viral hepatitis C is a significant public health challenge. The disease may remain clinically silent in both acute and chronic forms, and chronic infections may progress to advanced disease such as cirrhosis and hepatocellular carcinoma, requiring costly treatment, compromising the patient's quality of life and even leading to death. For this reason, it is one of the most frequent indications for liver transplantation. Although treatment with direct-acting antivirals represents remarkable progress, many patients are still infected and even those who cleared the viral infection must be followed due to their previous hepatic lesions, especially regarding the disturbances of lobular architecture and the sanguineal and lymphatic vessels. Objective To assess immunohistochemical aspects of lymphatic sprouts and mature lymphatic vascularity with histological variables of liver injury attributable to hepatitis C virus (HCV) and fatty disease. Methods The present study included 72 liver biopsies of cases with chronic hepatitis C. Morphologic changes reflecting "staging" and "activity" were analyzed. Immunohistochemical reactions were performed with monoclonal antibody D2-40 anti-podoplanin. Major histological variables were also semiquantified so as to enable the search for possible associations among histological and Immunohistochemical criteria, as well as with genotypes 1 and 3 of HCV. Results Histological findings showed that the different degrees of strutural changes were well represented in this casuistic. Intralobular/parenchymal necro-inflammatory activity was predominantly mild to moderate. Most cases did not show major evidences of fatty disease, which was found significantly higher in cases infected with HCV genotype 3. The amount of portal lymphatic sprouts increased along with the progression of structural changes, maximal at cirrhosis. Portal lymphatic sprouts as well as portal mature lymphatic vessels also showed an increase parallel to the increase in the degree of portal/septal inflammatory infiltrate. In the present study, no significant association was found between the proportion of portal lymphatic sprouts or portal mature lymphatic vessels and the degree of periportal/periseptal activity. No significant relations were detected between lymphatic sprouts/mature vessels and periportal or parenchymal inflammatory activity, nor with infections due to HCV genotype 1 or 3. Conclusion Visualization and semiquantitation of sprouts and mature lymphatic vessels were clearly yielded by Immunohistochemical staining with monoclonal antibody D2-40. The amount of lymphatics was increased along fibrogenic process, significantly related to progression of liver disease and maximal at cirrhosis. No significant relations were detected with necro-inflammatory activity at interface or in the parenchyma.

RESUMO Contexto A hepatite C é um relevante problema de saúde pública. A doença pode permanecer clinicamente silenciosa tanto na forma aguda como na crônica e as infecções crônicas podem progredir para doenças avançadas, tais como cirrose e carcinoma hepatocelular (CHC), requerendo tratamentos dispendiosos, comprometendo a qualidade de vida do paciente e até mesmo levando à morte. Por esta razão, é uma das indicações mais frequentes para o transplante hepático. Apesar da introdução do tratamento com antivirais de ação directa (AAD) representar um progresso notável, muitos pacientes não receberam o tratamento e continuam infectados, e mesmo aqueles que eliminaram a infecção viral devem ser seguidos devido às lesões hepáticas anteriores, especialmente no que diz respeito às alterações da arquitetura lobular e dos vasos sanguíneos e linfáticos. Objetivo Avaliar os aspectos imuno-histoquímicos dos brotos linfáticos e dos vasos linfáticos "maduros" com variáveis histológicas de lesão hepática atribuíveis ao vírus da hepatite C (VHC) e à doença gordurosa. Métodos O presente estudo incluiu 72 biópsias hepáticas em pacientes com hepatite C crônica. Foram analisadas alterações estruturais relativas a "estadiamento" e "atividade". Reações imuno-histoquímicas foram realizadas com anticorpo D2-40 anti-podoplanina. As principais variáveis histológicas também foram semiquantificadas, de modo a permitir a procura de possíveis associações entre os critérios histológicos e imunohistoquímicos, bem como com os genótipos 1 e 3 do VHC. Resultados Os achados histológicos mostraram que os diferentes graus de alterações estrutural estavam bem representados nesta casuística. A atividade necro-inflamatória lobular/parenquimatosa foi predominantemente leve à moderada. A maioria dos casos não apresentava grandes evidências de doença gordurosa, que foi encontrada significativamente mais elevada nos casos infectados com o genótipo 3 do VHC. A quantidade de brotos linfáticos portais aumentou com a progressão de alterações estruturais, sendo máxima na cirrose. Os brotos linfáticos portais, bem como os vasos linfáticos "maduros" portais também mostraram um aumento paralelo ao aumento do grau de infiltrado inflamatório portal/septal. No presente estudo, não foi encontrada qualquer associação significativa entre a proporção de brotos linfáticos portais ou vasos linfáticos maduros portais e o grau de atividade periportal/periseptal. Não foram detectadas relações significativas entre os brotos linfáticos/vasos maduros e a atividade inflamatória periportal ou atividade inflamatória parenquimatosa, nem com infecções devido ao genótipo 1 ou 3 do VHC. Conclusão A reação imunohistoquímica com anticorpo monoclonal D2-40 possibilitou a visualização e a semiquantitação de brotos e vasos linfáticos "maduros" nas amostras obtidas por biópsia hepática. A quantidade de linfáticos aumentou ao longo do processo fibrogênico, significativamente relacionada com a progressão da doença hepática e máxima na cirrose. Não foram detectadas relações significativas com a atividade necro-inflamatória periportal ou parenquimatosa.

Minor Salivary Gland Transplantation for Severe Dry Eyes.

Dry eye is a multifactorial disease comprising a wide spectrum of ocular surface alterations and symptoms of discomfort. In most patients with aqueous-deficient dry eye, pharmaceutical tear substitutes are used to control symptoms and prevent ocular surface damage. However, in severe dry eye conditions caused by cicatricial disorders, such as Stevens-Johnson syndrome and ocular cicatricial mucous membrane pemphigoid, noninvasive treatments are insufficient, and patients are at risk of developing complications that can lead to blindness. The use of salivary glands as a source of lubrication to treat severe cases of dry eye has been proposed by different authors. The first reports proposed parotid or submandibular gland duct transplantation into the conjunctival fornix. However, complications limited the functional outcomes. Minor salivary gland autotransplantation together with labial mucosa has been used as a complex graft to the conjunctival fornix in severe dry eye with a good outcome. Our group demonstrated significant improvements in best-corrected visual acuity, Schirmer I test score, corneal transparency, and neovascularization after using this technique. A symptoms questionnaire applied to these patients revealed improvements in foreign body sensation, photophobia, and pain. Similar to tears, saliva has a complex final composition comprising electrolytes, immunoglobulins, proteins, enzymes, and mucins. We demonstrated the viability of minor salivary glands transplanted into the fornix of patients with dry eye by performing immunohistochemistry on graft biopsies with antibodies against lactoferrin, lysozyme, MUC1, and MUC16. The findings revealed the presence of functional salivary gland units, indicating local production of proteins, enzymes, and mucins.

Difference in adhesion molecule expression (ICAM-1 and VCAM-1) in juvenile and adult dermatomyositis, polymyositis and inclusion body myositis.

To assess the differential expression of adhesion molecules ICAM-1 and VCAM-1 in vessels and muscle fibers in acquired inflammatory myopathy, a series comprising thirty-seven muscle biopsy specimens from patients with JDM, fifteen with DM, fifteen with PM and seven with IBM was studied. Histochemical and immunohistochemical tests (StreptABCcomplex/HRP) for ICAM-1 and VCAM-1 (Dakopatts) were performed in serial frozen sections. ICAM-1 expression in vessels was significantly (p<0.0001) more present in JDM than PM, DM or IBM. However, in muscle fibers, ICAM-1 expression was absent in both JDM and IBM, but present in 33.4% and 40% in PM and DM respectively (p<0.0001). VCAM-1 expression in vessels was significantly more present in PM and DM than JDM and IBM (p<0.0001) while VCAM-1 expression in muscle fibers was almost absent in the four groups (p=0.2632). These findings emphasize the importance of adhesion molecules in the pathophysiology of the inflammatory myopathies, mainly the marked ICAM-1 expression in vessels in JDM, corroborating the microvascular involvement in this disease. In contrast, VCAM-1 seems not to play a major role in JDM, as previously described in PM, DM and IBM. Adhesion molecule expression in JDM presents a differential characteristic when compared to PM, DM and IBM.