Lymphangiogenesis in Crohn's disease: an immunohistochemical study using monoclonal antibody D2-40.

Crohn's disease (CD) is a chronic inflammatory bowel disorder of unknown etiology. An involvement of the intestinal lymphatic system has been suggested. Recently, monoclonal antibodies have become available to distinguish lymphatic vessels from blood vessels. The aim of the study was to examine the distribution of lymphatic vessels in ileal and colic walls of patients affected by CD and compare it with healthy controls and other inflammatory bowel diseases. Twenty-eight cases of CD, 13 cases of other inflammatory bowel diseases, and 10 normal ileal and colic walls were studied. Immunohistochemical staining was performed using the monoclonal antibody D2-40. Quantification of lymphatic vessels was performed by identifying four fields with high density of lymphatics and then counting the number of lymphatic vessels at high resolution. Lymphatic diameter was also evaluated by using an ocular micrometer. Lymphatic vessels showed the highest density in CD specimens. The median number of lymphatics was significantly higher both in ileal and colic samples of CD than the other inflammatory diseases as well as normal controls. Moreover, in patients with CD, diffuse lymphangiectasia was also observed. The present data suggest that lymphangiogenesis and lymphangiectasia probably play a role in the pathogenesis of CD.

[Albumin mRNA and pCEA in the histopathologic diagnosis of hepatocellular carcinoma]. / mRNA dell'albumina e pCEA nella diagnosi istopatologica del carcinoma epatocellulare.

Extrahepatic neoplasms metastatic to the liver histologically are often indistinguishable from hepatocellular carcinoma (HCC). The differential diagnosis between HCC and metastatic liver tumours can be even more difficult in ultrasound guided fine-needle biopsies. Purpose of the present study was to investigate the utility of immunohistochemical staining with polyclonal anticarcinoembryonic antigen (pCEA) antibody and of in situ hybridization (ISH) revealing human albumin mRNA, with emphasis on tissues obtained via fine-needle procedure. Cases consisted of 52 primary HCC; 2 HCC metastatic to vertebral bones; 18 tumours metastatic to the liver; 24 non-hepatocellular tumours metastatic to the skin, lymph nodes and brain; 2 immature teratomas with areas of hepatoid differentiation. Forty-seven HCC (90%) and 7 liver metastases (38%) were obtained by ultrasound guided fine-needle biopsies (21 g needle was used). All the remaining cases were surgical specimens. All the cases were studied with immunohistochemistry for pCEA and ISH using a cRNA probe for human albumin mRNA. The immunohistochemical staining using pCEA showed a canalicular type of positivity in 37 cases of HCC (71%), in one HCC metastatic to vertebral bone and in the hepatoid areas of one immature teratoma. No canalicular type of positivity was obtained in non-hepatocellular neoplasms metastatic to the skin, brain, lymph-nodes and liver. Albumin mRNA was detected in 51 (98%) primary HCC, in both HCC bone metastases, and in the hepatoid areas of both immature teratomas. No positivity was obtained in non-hepatocellular tumours. The data here obtained indicate that immunostaining with pCEA and ISH revealing human albumin mRNA are markers of hepatocellular differentiation and confirm their diagnostic utility. Detection of albumin mRNA showed a higher sensitivity. In addition the cRNA probe here used seems more sensitive that the oligonucleotide probes employed in previous studies.

Albumin gene expression in adenocarcinomas with hepatoid differentiation.

Two cases of hepatoid adenocarcinomas were studied with an in situ hybridization technique (ISH) using a RNA probe for human albumin mRNA. In case 1 the urinary bladder of a 67-year-old woman was affected; in case 2 the tumour was located in the gastric antrum of an 80-year-old woman. In neither case had alpha fetoprotein (AFP) been determined preoperatively. Histologically these cases showed adenocarcinomatous features intermingled with hepatoid areas. These latter areas were characterized by cords of polygonal cells, each with an oval nucleus and prominent nucleoli, separated by a fine network of sinusoids. In the hepatoid areas the immunohistochemical profile was similar to that observed in hepatocellular carcinomas, in that the tumour cells were positive with AFP, alpha-1-antitrypsin (A1AAT) and albumin antisera and there was a canalicular type of reactivity with polyclonal anti-CEA (pCEA) antibody. ISH revealed albumin mRNA in virtually all hepatoid cells in case 1, and in about 50% of those in case 2. In addition, in case 2 occasional cells in the adenocarcinomatous areas showed albumin transcripts of ISH. Our findings confirm that ISH for albumin mRNA probe is a valuable method of establishing hepatocellular differentiation, and that hepatoid adenocarcinomas are tumours with true extrahepatic hepatocellular differentiation.

[Malignant melanoma with pseudoepitheliomatous reaction marker. A case report]. / Melanoma maligno con marcata reazione pseudoepiteliomatosa. Descrizione di un caso.

Pseudoepitheliomatous hyperplasia or pseudocarcinomatous hyperplasia (PEH) is characterized by a downward expansion of the epidermis, which can simulate a squamous cell carcinoma (SC). It is usually associated to chronic inflammatory conditions, but rarely it can hide a tumour. In the present paper a case of melanoma (M) associated with a prominent PEH is described. The patient is a 79-year old woman who presented a polypoid, ulcerated lesion of the left thigh. The lesion was entirely removed. The patient is free of disease 5-years after surgery. On histology, the malignant melanomatous proliferation was closely admixed to sheets of squamous cells. The possibility of SC was excluded as the squamous component did not show architectural disarray, prominent nucleoli and atypical mitoses. Siringomatous metaplasia was observed in the deeper portion of the lesion. On the basis of these findings the diagnosis of melanoma (M) associated to prominent PEH was considered the most likely.

Prenatal exposure to ethanol in rats: effects on liver energy level and antioxidant status in mothers, fetuses, and newborns.

The fetal alcohol syndrome is a clinical condition that affects newborns from alcoholic mothers. It is not clear, however, whether ethanol consumption during gestation can affect liver functions of fetuses and newborns. In this study, we aimed to assess the effects of ethanol administration on body weight, liver energy level, and antioxidant status of mothers, fetuses, and newborns. Pregnant rats were exposed to ethanol during the third week of gestation. Body weight, survival, and liver concentration of gluthatione (GSH) and adenosintriphosphate (ATP) were measured. No differences were observed in body weight or in liver ATP and GSH between mothers exposed to ethanol and control animals. Conversely, fetuses from rats exposed to ethanol showed a marked decrease in GSH, ATP, and body weight when compared to those from control rats. Newborns exposed prenatally to ethanol were no different from those born to control mothers. This study suggests that an amount of ethanol that is not sufficient to determine a significant effect on mothers can, nevertheless, cause a marked decrease in growth and in liver antioxidant and energy status in fetuses. These parameters, however, return to control value one week after ethanol discontinuation.

Complete eradication of hepatitis C virus after interferon treatment for chronic hepatitis C.

BACKGROUND: Alpha-interferon therapy can lead to a persistent biochemical response, but discordant opinions have been expressed on the definition of sustained response and on the real possibility of complete eradication of hepatitis C virus (HCV). AIMS: To define the clinical, virological and histologic profiles of the patients with sustained response. PATIENTS: Twenty-eight patients with three different biochemical and virological patterns of response to interferon therapy (16 sustained responders, 6 responders with relapse and 6 non responders) were studied for a follow-up period of 36 months. METHODS: HCV-RNA sequences were investigated in serum, peripheral blood mononuclear cells and in liver tissue by means of reverse transcriptase-polymerase chain reaction, targeted to the 5' non coding region. Viral load in serum was quantified by branched-DNA signal amplification. HCV genotypes were evaluated using a line probe assay. RESULTS: All sustained responders showed persistent normal ALT values and loss of serum HCV-RNA during the treatment and in the entire follow-up period. The HCV clearance was also demonstrated in peripheral blood mononuclear cells and in liver tissue. Pre-treatment HCV-RNA quantitation showed that sustained responders had a significantly lower viral load compared to relapsers and non responders (p = 0.005). HCV genotyping showed that patients infected by genotypes 2a, 3a were more likely to achieve a sustained response. Interestingly, a prolonged response was also observed in the only three patients with pre-treatment detectable viral load infected by genotype 3a and in patients with genotype 1b and low viraemia levels. To assess the histologic outcome following HCV eradication, all sustained responders underwent a second liver biopsy in the follow-up period (6-18 months). Periportal necrosis and portal inflammation were significantly improved. CONCLUSIONS: Our results suggest that persistent loss of HCV-RNA in serum, peripheral blood mononuclear cells and liver as well as histologic improvement are consistent with the complete HCV eradication even from intracellular compartments and from potential extra-hepatic sites of viral persistence. Moreover, pre-treatment viral load, HCV infecting genotypes and histologic features may influence the clinical outcome of hepatitis C and the response to interferon therapy.

Histogenesis of primary liver carcinomas: strengths and weaknesses of cytokeratin profile and albumin mRNA detection.

To assess the utility of cytokeratin (CK) profile and albumin mRNA detection (as revealed by in situ hybridization) in the differential diagnosis of primary liver carcinomas (PLCs) we evaluated a series of surgically resected PLCs, comprising 20 "pure" hepatocellular carcinomas (HCCs) (10 well-differentiated, 10 poorly differentiated), 15 cholangiocarcinomas (CCs) (6 peripheral, 5 hilar, and 4 major duct ones) and 10 hepatocholangio-carcinomas (HCC-CCs). 11 of 20 (55%) of the pure HCCs expressed CKs of pure hepatocytic lineage (CK 8 and CK 18); 2 of 10 (20%) of the HCC-CCs displayed only hepatocytic profile, whereas 12 of 15 (80%) of the CCs evidenced mature bile duct cell phenotype (CK 8, CK 18, CK 7, CK 19). All HCCs expressed varying distributions of albumin mRNA, whereas 4 of 6 (67%) peripheral CCs showed cells with focal positivity for albumin mRNA. This suggests that the phenotypic expression of PLC cells are often not fixed, and in particular: (1) peripheral CCs have a different phenotype from hilar and large duct ones; (2) the CK profile and albumin mRNA expression in peripheral CCs show many similarities with those of some HCCs. Furthermore, the results show that a mixed biological phenotype (ie, CK 8, CK 18 and CK 7 and/or CK 19) can be found both among morphologically pure HCCs and peripheral CCs, suggesting that these two forms could share a common histogenesis. We think that special attention should be given to cases in which CK profile and albumin mRNA reveal mixed phenotype, as these tumors could have different biological behavior and respond differently to therapy.

HCV-associated liver cancer without cirrhosis.

Chronic infection with hepatitis C virus (HCV) is regarded as a risk factor for hepatocellular cancer, mostly in patients with liver cirrhosis. We looked for HCV genomes in the livers of patients with hepatocellular cancer who did not have cirrhosis to see whether HCV was directly oncogenic. Cancerous and non-cancerous liver tissue, and serum samples from 19 patients negative for hepatitis B surface antigen were analysed by polymerase chain reaction for the presence of HCV genome, HCV replication, HCV genotyping, and HBV genome. 13 of 19 patients were HCV RNA-positive in cancerous and non-cancerous liver tissue; 8 of 17 tested were anti-HCV positive. Among the 13 HCV RNA-positive patients, 11 had genotype 1b and 2 had genotype 2a. 7 of 13 serum samples were HCV RNA positive. 7 of 19 patients were HBV DNA positive in cancerous and non-cancerous liver tissue, 5 of them anti-HBc positive. 4 patients were both HCV RNA and HBV DNA positive and 3 were both HCV RNA and HBV DNA negative. Our results provide evidence for the association of HCV, mostly genotype 1b, with hepatocellular cancer without the intermediate step of cirrhosis.

Gelatinase A (MMP-2) and its mRNA detected in both neoplastic and stromal cells of tumors with different invasive and metastatic properties.

Simultaneous presence of gelatinase A (MMP-2) and MMP-2 messenger RNA (mRNA) in 30 malignant tumors with various degrees of differentiation and biological behavior was evaluated by immunohistochemistry and in situ hybridization. The series consisted of 10 gastric carcinomas, 10 colorectal carcinomas, five squamous skin carcinomas, and five basal cell skin tumors. MMP-2 was detected in all cases. MMP-2 mRNA was expressed in the stromal cells in all cases and was more marked in the less-differentiated gastric and colonic carcinomas; it was also detected in the neoplastic cells of poorly differentiated tumors, particularly in those of the signet-ring cell type, both in the colon and stomach. The study confirmed that stromal cells have a specific role in tumor invasion and suggests a direct relationship between neoplastic epithelium and stromal cells in the most aggressive varieties.

Overexpression of p53 protein and Ki67 proliferative index in hepatocellular carcinoma: an immunohistochemical study on 109 Italian patients.

The overexpression of p53 protein and the Ki67 proliferative index was evaluated in 96 hepatocellular carcinomas (HCC), 67 in cirrhotic livers and 29 in non-cirrhotic ones, and in 13 non-carcinomatous lesions, all surgically resected from Italian patients. Overexpression of p53 was detected only in carcinomatous lesions, and was significantly related to the grade of HCC (P < 0.001). In fact, p53 was observed in 7/7 (100%) cases of grade IV, 13/43 (30.3%) of grade III, and 10/46 (21.7%) of grade II. The relationship between p53 and Ki67 scores was determined in serial sections from corresponding areas of both diffuse and patchy immunoreactivity. In the overall population, p53-positive tumors showed a significantly higher Ki67 score (15.9 +/- 5.5% vs 9.2 +/- 4.3% [P < 0.001]). This observation was evident in all grades of HCC.

Different in situ expression of insulin-like growth factor type II in hepatocellular carcinoma. An in situ hybridization and immunohistochemical study.

Reexpression of the insulin-like growth factor type II (IGF-II) gene has recently been described in hepatocellular carcinoma (HCC). In this study, we used a nonisotopic in situ hybridization method to analyze the expression of IGF-II mRNA in a series of 28 HCCs arising on cirrhotic and noncirrhotic livers. An immunohistochemical method was used to detect IGF-II peptide. Hepatitis B virus (HBV) status and the histological differentiation degree were also evaluated. Increased expression of IGF-II mRNA was found in 4 of 28 HCCs, and 7 of 17 cirrhotic patients showed IGF-II mRNA in the cirrhotic nodules surrounding the HCC. A slightly higher rate of positivity for IGF-II mRNA was found in the HBV-negative patients than in HBV-positive ones. Positive immunostaining for the IGF-II peptide in the HCC and/or in surrounding cirrhotic nodules was found in 10 of 28 cases. The normal hepatocytes of the noncirrhotic patients were always negative for IGF-II peptide and mRNA. The similarities between our results and those from experimental models in woodchucks seem to support the concept that heterogeneous phenotypic groups could exist in human HCCs.

Expression of insulin-like growth factor II (IGF-II) in human hepatocellular carcinomas: an immunohistochemical study.

Recent results obtained using molecular biology techniques have suggested a possible role for insulin-like growth factor II (IGF-II) in the pathogenesis of hepatocellular carcinoma (HCC). To investigate this phenomenon, a monoclonal antibody was used against IGF-II to study 54 patients with HCC. The presence of HBsAg was also tested both in serum and liver tissue. A positive immunoreaction was found in 9/15 (60%) of the HCC arising in cirrhotic livers of patients who had serum markers for HBV (HBV + positive patients). These results provide further evidence that HBV might play a role in the expression of IGF-II. In HCC of patients without any markers of HBV infection (HBV- negative patients), IGF-II was detected in 10/39 (25.6%) of the tumors, and in some benign neoplastic lesions. It was found not only in neoplastic cells but also in some dysplastic nodules. The speculation arises that IGF-II expression may play a role in some steps of hepato-carcinogenesis.

Detection of anti-sense transcripts of the insulin-like growth factor-2 gene in Wilms' tumor.

The expression of the insulin-like growth factor-2 (IGF-2) gene was studied by means of both in situ hybridization and immunohistochemistry in eight cases of Wilms' tumor with different histological features. An anti-sense cRNA IGF-2 probe revealed the presence of abundant IGF-2 mRNAs in all eight tumors examined, localized in the most undifferentiated tumoral cells (blastemal cells); none of the tumors showed immunoreactivity for the anti-IGF-2 antibody. Using a sense cRNA IGF-2 probe, we also detected anti-sense transcripts of the IGF-2 gene in five of eight tumors. These transcripts were exclusively localized in the cells expressing the IGF-2 mRNAs. Although the function of these anti-sense transcripts is unknown, we think that their presence could explain the lack of IGF-2 peptides in Wilms' tumors despite increased expression of IGF-2 mRNAs.

Pericardial multicystic proliferation.

We report the case of an intrapericardial lesion with the pathological features of a multilocular cyst, found on the adventitia of an aortic aneurysm in a 62-yr-old man. Microscopically, it consisted of numerous cavities lined by flattened or cuboidal cells with the immunocytochemical and electron microscopical features of mesothelium, sometimes forming a hyperplastic pattern. Numerous nerve bundles and collections of inflammatory cells were present in the stroma. These features were consistent with a reactive lesion.

Detection of hepatitis C virus (HCV) RNA sequences in liver tissue by in situ hybridization.

In situ hybridization was used to identify the cell types infected by hepatitis C virus (HCV) in the liver. Using an antisense HCV-RNA probe from the 5' non-coding region, HCV-RNAs molecules were detected in liver sections of 4/11 patients with chronic hepatitis C. These 4 positive subjects were also infected by HIV. HCV-RNA-positive strands were detected in scattered hepatocytes as well as in cells identified as mononuclear cells within the inflammatory infiltrates. HCV-RNA negative strands, likely replicative intermediates, were also detected in these cells. This study therefore indicates that replication of HCV may occur in both hepatocytes and mononuclear liver cells.

Evaluation of hepatocellular carcinoma aggressiveness by a panel of extracellular matrix antigens.

Invasion and metastasis requires a series of interactions between malignant cells and the extracellular matrix (ECM). Antigen markers that relate to these interactions were evaluated for prognostic correlation in human hepatocellular carcinoma. Basement membrane type IV collagen (cIV), type IV collagenase (cIVase), laminin, and laminin receptors (LRs)--all ECM antigens previously proposed to be modulated in association with tumor aggressiveness--were immunohistochemically investigated in 30 cases of hepatocellular carcinomas (HCCs). The pattern of antigen expression was correlated with 1) 36 months' clinical follow-up and 2) the pathologic grade. As a means of estimating the proliferation fraction, an additional antigen, Ki67, was also studied in this series. There were major differences in the distribution of cIV and laminin, and in the quantity of cIVase-, LR-, and Ki67-positive cells associated with grade and prognosis. A smaller quantity of cIV and laminin and a higher number of cIVase-, LR-, and Ki67-positive cells were detected in the poorly differentiated compared with the well-differentiated HCCs. The tumors with lower immunoreactivity for cIV and laminin components accompanied by a higher number of cIVase-, LR-, and Ki67-positive cells fall into a group with the poorest overall survival (P less than 0.006). The panel of antigens is proposed as a useful prognostic tool for evaluating HCC tumor aggressiveness.

Thermal stability of foot-and-mouth disease virus.

The thermal stabilities of 146S component of seven strains of foot-and-mouth disease virus were found to differ considerably. Inactivation of infectivity with acetylethyleneimine (AEI) reduced the thermal stabilities of all but one of the viruses. Treatment of AEI inactivated and control virus preparations with glutaraldehyde stabilized 146S particles to a considerable extent, whereas treatment with dimethyl suberimidate was less effective. In similar experiments with 75S, natural empty particles, the thermal stabilities were lower than those of the corresponding 146 S particles. Treatment of 75S particles with AEI appeared to have no direct effect on the protein-protein interactions involved in 75S capsid integrity. As with 146S particles, glutaraldehyde stabilized 75S particles.