Senescence markers in focal nodular hyperplasia of the liver: pathogenic considerations on the basis of immunohistochemical results.

Focal nodular hyperplasia (FNH) is a polyclonal tumour-like hepatic lesion characterised by parenchymal nodules, connective tissue septa without interlobular bile ducts, pronounced ductular reaction and inflammation. It may represent a response to local arterial hyperperfusion and hyperoxygenation resulting in oxidative stress. We aimed at obtaining closer insight into the pathogenesis of FNH with its characteristic morphologic features. Immunohistochemistry and immunofluorescence microscopy was performed on FNH specimens using antibodies against keratins (K) 7 and 19, neural cell adhesion molecule (NCAM), lamin B1, senescence markers (CDK inhibitor 1/p21Cip1, CDK inhibitor /p16Ink4a, senescence-associated (SA) ß- galactosidase activity), proliferation markers (Ki-67, proliferating-cell nuclear antigen (PCNA)), and the abnormally phosphorylated histone γ-H2AX, indicating DNA double strand breaks; moreover SA ß- galactosidase activity was determined histochemically. Ductular metaplasia of hepatocytes indicated by K7 expression in the absence of K19 plays a major role in the development of ductular reaction in FNH. Moreover, the expression of senescence markers (p21Cip1, p16Ink4a, γ-H2AX, SA ß-galactosidase activity) in hepatocytes and cholangiocytes suggests that stress-induced cellular senescence contributes to fibrosis and inflammation via production of components of the senescence-associated secretory phenotype. Expression of proliferation markers (Ki-67, PCNA) was not enhanced in hepatocytes and biliary cells. Senescence and ductular metaplasia of hepatocytes may thus be involved in inflammation, fibrosis and apoptosis resistance. Hence, fibrosis, inflammation and reduced apoptotic cell death, rather than proliferation (hyperplasia) may be responsible for increased tissue mass and tumour-like appearance of FNH.

Role of placental barrier integrity in infection by Trypanosoma cruzi.

American trypanosomiasis has long been a neglected disease endemic in LatinAmerica, but congenital transmission has now spread Chagas disease to cause a global health problem. As the early stages of the infection of placental tissue and the vertical transmission by Trypanosoma cruzi are still not well understood, it is important to investigate the relevance of the first structure of the placental barrier in chorionic villi infection by T. cruzi during the initial stage of the infection. Explants of human chorionic villi from healthy pregnant women at term were denuded of their syncytiotrophoblast and co-cultured for 3h, 24h and 96h with 800,000 trypomastigotes (simulating acute infection). T. cruzi infected cells were identified by immunohistochemistry for cytokeratin-7 (+cytotrophoblast) and CD68 (+macrophages), and the infection was quantified. In placental tissue, the parasite load was analyzed by qPCR and microscopy, and the motile trypomastigotes were quantified in culture supernatant. In denuded chorionic villous, the total area occupied by the parasite (451.23µm2, 1.33%) and parasite load (RQ: 87) was significantly higher (p<0.05) than in the entire villous (control) (5.98µm2, 0.016%) (RQ:1) and with smaller concentration of nitric oxide. Stromal non-macrophage cells were infected as well as cytotrophoblasts and some macrophages, but with significant differences being observed. The parasite quantity in the culture supernatant was significantly higher (p<0.05) in denuded culture explants from 96h of culture. Although the human complete chorionic villi limited the infection, the detachment of the first structure of the placenta barrier (syncytiotrophoblast) increased both the infection of the villous stroma and the living trypomastigotes in the culture supernatant. Therefore structural and functional alterations to chorionic villi placental barrier reduce placental defenses and may contribute to the vertical transmission of Chagas.

Small biomolecule immunosensing with plasmonic optical fiber grating sensor.

This study reports on the development of a surface plasmon resonance (SPR) optical fiber biosensor based on tilted fiber Bragg grating technology for direct detection of small biomarkers of interest for lung cancer diagnosis. Since SPR principle relies on the refractive index modifications to sensitively detect mass changes at the gold coated surface, we have proposed here a comparative study in relation to the target size. Two cytokeratin 7 (CK7) samples with a molecular weight ranging from 78 kDa to 2.6 kDa, respectively CK7 full protein and CK7 peptide, have been used for label-free monitoring. This work has first consisted in the elaboration and the characterization of a robust and reproducible bioreceptor, based on antibody/antigen cross-linking. Immobilized antibodies were then utilized as binding agents to investigate the sensitivity of the biosensor towards the two CK7 antigens. Results have highlighted a very good sensitivity of the biosensor response for both samples diluted in phosphate buffer with a higher limit of detection for the larger CK7 full protein. The most groundbreaking nature of this study relies on the detection of small biomolecule CK7 peptides in buffer and in the presence of complex media such as serum, achieving a limit of detection of 0.4 nM.

ApoE Receptor 2 Mediation of Trophoblast Dysfunction and Pregnancy Complications Induced by Antiphospholipid Antibodies in Mice.

OBJECTIVE: Pregnancies in women with the antiphospholipid syndrome (APS) are frequently complicated by fetal loss and intrauterine growth restriction (IUGR). How circulating antiphospholipid antibodies (aPL) cause pregnancy complications in APS is poorly understood. We sought to determine whether the low-density lipoprotein receptor family member apolipoprotein E receptor 2 (ApoER2) mediates trophoblast dysfunction and pregnancy complications induced by aPL. METHODS: Placental and trophoblast ApoER2 expression was evaluated by immunohistochemistry and immunoblotting. Normal human IgG and aPL were purified from healthy individuals and APS patients, respectively. The role of ApoER2 in aPL-induced changes in trophoblast proliferation and migration and in kinase activation was assessed using RNA interference in HTR-8/SVneo cells. The participation of ApoER2 in aPL-induced pregnancy loss and IUGR was evaluated in pregnant ApoER2(+/+) and ApoER2(-/-) mice injected with aPL or normal human IgG. RESULTS: We found that ApoER2 is abundant in human and mouse placental trophoblasts and in multiple trophoblast-derived cell lines, including HTR-8/SVneo cells. ApoER2 and its interaction with the cell surface protein ß2 -glycoprotein I were required for aPL-induced inhibition of cultured trophoblast proliferation and migration. In parallel, aPL antagonism of Akt kinase activation by epidermal growth factor in trophoblasts was mediated by ApoER2. Furthermore, in a murine passive-transfer model of pregnancy complications of APS, ApoER2(-/-) mice were protected from both aPL-induced fetal loss and aPL-induced IUGR. CONCLUSION: ApoER2 plays a major role in the attenuation of trophoblast function by aPL, and the receptor mediates aPL-induced pregnancy complications in vivo in mice. ApoER2-directed interventions can now potentially be developed to combat the pregnancy complications associated with APS.

Coordinate expression of cytokeratins 7 and 14, vimentin, and Bcl-2 in canine cutaneous epithelial tumors and cysts.

Forty-seven canine cutaneous epithelial tumors and cysts were examined to determine coordinate expression of cytokeratins 7 (CK7) and 14 (CK14), vimentin, and Bcl-2 using commercially available antibodies. Within non-affected normal skin adjacent to tumors or cysts, CK7 expression was observed in luminal cells in apocrine glands; CK14 expression was observed in the stratum basale, stratum spinosum, stratum granulosum, basal layer of outer root sheath, sebaceous glands, and myoepithelial cells of apocrine glands; vimentin expression was observed in dermal papilla and scattered non-epithelial cells within the epidermis; and Bcl-2 expression was observed in scattered non-epithelial cells in the epidermis and some apocrine glands. The pattern of expression of CK7 and CK14 in cases of adenocarcinoma of the apocrine gland of the anal sac (CK7+/CK14-) and hepatoid gland tumors (CK7-/CK14+) may prove useful for diagnostic purposes. Loss of expression of CK14 and vimentin, identifying myoepithelial cells, was observed in apocrine and ceruminous adenocarcinomas. Differences in patterns of expression of Bcl-2 were observed between infundibular keratinizing acanthomas compared to trichoepitheliomas.

High salt buffer improves integrity of RNA after fluorescence-activated cell sorting of intracellular labeled cells.

Over the past years, massive progress has been made in the ability to collect large-scale gene expression data from a limited sample size. Combined with improvements in multiplex flow cytometry-based techniques, this has made it possible to isolate and characterize specific cellular subtypes within heterogeneous populations, with a great impact on our understanding of different biological processes. However, sorting based on intracellular markers requires fixation and permeabilization of samples, and very often the integrity of RNA molecules is compromised during this process. Many attempts have been made to improve the quality of nucleic acids from such samples, but RNA degradation still remains a limiting factor for downstream analyses. Here we present a method to isolate high quality RNA from cells that have been fixed, permeabilized, intracellularly labeled and sorted. By performing all incubation steps in the presence of a high salt buffer, RNA degradation was avoided and samples with remarkable integrity were obtained. This procedure offers a straightforward and very affordable technique to retrieve high quality RNA from isolated cell populations, which increases the possibilities to characterize gene expression profiles of subpopulations from mixed samples, a technique with implications in a broad range of research fields.

The clinical use of a P63/cytokeratin7/18/cytokeratin5/14 antibody cocktail in diagnostic breast pathology.

An antibody cocktail directed against p63, cytokeratin (CK)5/14, and CK7/18 is reported to be useful in distinguishing noninvasive from invasive breast lesions and for the characterization of intraductal epithelial proliferations. However, limited studies evaluate its use in clinical practice. A retrospective review of breast material at a university medical center identified cases that were immunostained with the above antibody cocktail. Additional p63 immunostaining alone was performed to further determine the utility of the antibody cocktail in the evaluation of invasion. Of 50 breast cases identified, the antibody cocktail was used to confirm or exclude invasion in 44 (88%). Twenty-two (50%) of these had easily identifiable p63/CK5/14-positive myoepithelial cells, whereas the remainder lacked such staining, confirming the diagnosis of invasive carcinoma. In 27 cases with available diagnostic material for additional p63 immunostaining, the cocktail better highlighted myoepithelial cells by staining nuclei and cytoplasm. Easier identification of invasion was also facilitated by CK7/18 expression in invasive foci, especially those composed of single cells. Ten cases were immunostained to help determine the nature of an intraductal proliferation. The cocktail demonstrated a mosaic staining pattern of both CK7/18- and CK5/14-positive epithelial cells in 3 (30%) cases consistent with usual hyperplasia; homogenous CK7/18 expression in the remaining cases supported the diagnosis of atypical ductal hyperplasia or carcinoma in situ. In summary, the p63/CK7/18/CK5/14 cocktail stain appears to be a useful tool in diagnostic breast pathology, in the evaluation of possible invasion, particularly in the setting of minute foci of invasion as well as in epithelial proliferations.

Development of pathological diagnostics of human kidney cancer by multiple staining using new fluorescent Fluolid dyes.

New fluorescent Fluolid dyes have advantages over others such as stability against heat, dryness, and excess light. Here, we performed simultaneous immunostaining of renal tumors, clear cell renal cell carcinoma (RCC), papillary RCC, chromophobe RCC, acquired cystic disease-associated RCC (ACD-RCC), and renal angiomyolipoma (AML), with primary antibodies against Kank1, cytokeratin 7 (CK7), and CD10, which were detected with secondary antibodies labeled with Fluolid-Orange, Fluolid-Green, and Alexa Fluor 647, respectively. Kank1 was stained in normal renal tubules, papillary RCC, and ACD-RCC, and weakly or negatively in all other tumors. CK7 was positive in normal renal tubules, papillary RCC, and ACD-RCC. In contrast, CD10 was expressed in renal tubules and clear cell RCC, papillary RCC, AML, and AC-RCC, and weakly in chromophobe RCC. These results may contribute to differentiating renal tumors and subtypes of RCCs. We also examined the stability of fluorescence and found that fluorescent images of Fluolid dyes were identical between a tissue section and the same section after it was stored for almost three years at room temperature. This indicates that tissue sections can be stored at room temperature for a relatively long time after they are stained with multiple fluorescent markers, which could open a door for pathological diagnostics.

Native liver histology after successful portoenterostomy in biliary atresia.

BACKGROUND: Biliary atresia is the most common indication for childhood liver transplantation. The effects of successful portoenterostomy (PE) on native liver histology remain unclear. AIMS: We assessed changes in native liver histology after a successful PE in relation to liver function and clinical outcomes. METHODS: In total, 70 native liver biopsies of 44 biliary atresia patients were obtained at PE (n=30), 4.2 years after successful PE (n=23) and 1.1 years after failed PE (n=17), and reviewed for cholestasis, fibrosis, inflammation, and cytokeratin 7 (CK7) immunopositivity (chronic cholestasis). Ten transplant donor livers served as controls. RESULTS: After a successful PE [serum bilirubin 11 (2 to 35) µmol/L at biopsy], histologic native liver cholestasis completely resolved in 83% of the patients and portal inflammation significantly decreased. Nevertheless, enhanced fibrosis [Metavir stage 2 (1-4) vs. 4 (1-4)], bile duct proliferation [grade 2 (1-2) vs. 1 (0-2)], and periportal CK7 immunostaining [grade 1 (0-2) vs. 1 (0-4)] persisted in 100%, 87%, and 61% of subjects, respectively. Metavir fibrosis stage corresponded cirrhosis (stage 4) in 52% of the patients, associated with the presence of portal hypertension, and correlated with serum-conjugated bilirubin (r=0.601, P=0.002), bile duct proliferation (r=0.657, P=0.001), and CK7 positivity (r=0.657, P=0.001). Aspartate transferase to platelet ratio index predicted native liver fibrosis and development of esophageal varices. The degree of fibrosis and portal inflammation at PE were unrelated to native liver survival. CONCLUSIONS: Despite resolution of cholestasis and decreasing inflammation, bile duct proliferation, periportal CK7 immunostaining, and fibrosis persist after successful PE. Fibrosis is associated with biochemical cholestasis, bile duct proliferation, CK7 immunopositivity (chronic cholestasis), and development of portal hypertension.

A simple multicolor flow cytometry protocol for detection and molecular characterization of circulating tumor cells in epithelial cancers.

Circulating tumor cells (CTCs) might not only serve as prognostic marker but could also be useful for monitoring treatment efficacy. A multicolor flow cytometry protocol for their detection and molecular characterization in peripheral blood was developed which consisted of erythrocyte lysis followed by staining of cells with fluorochrome-labeled antibodies against CD45 and the epithelial markers EpCam and cytokeratin 7/8. For reducing the number of events acquired by flow cytometry, an electronic threshold for the fluorescent signals from the epithelial markers was applied. After establishment of the protocol by using spiking experiments, its suitability to determine the absolute number of CTCs as well as their expression of epidermal growth factor receptor (EGFR) and its phosphorylated form (phospho-EGFR) in blood samples from patients with squamous cell carcinoma of the head and neck (SCCHN) was validated. Spiking experiments demonstrated an excellent recovery (mean 85%) and a linear performance (R(2) = 0.98) of the protocol. Sensitivity and specificity were comparable to our former protocol using immunomagnetic CTC pre-enrichment. The analysis of 33 SCCHN patient samples revealed the presence of CTCs in 33.3% of cases with a mean ± SD of 1.5 ± 0.5 CTCs per 3.75 ml blood. EGFR was expressed in 100% and phospho-EGFR in 36.4% of the CTC+ cases. We have established a simple and sensitive multicolor flow cytometry protocol for detection of CTCs in patients with epithelial cancers including SCCHN which will allow their detailed molecular characterization.

Clinicopathological features and immunoprofile of 30 cases of Brenner ovarian tumors.

AIM: The aim of this study was to investigate the clinicopathological and immunopathological features of Brenner ovarian tumors. MATERIALS AND METHODS: Thirty cases of Brenner ovarian tumors were examined in our laboratory among 1,680 cases of ovarian tumors, representing 1.5% of all tumors examined. Blocks of paraffin-embedded tumor tissue for all cases were available for additional immunohistochemical stain by a Ventana autoimmunostainer. Moreover, antibodies for Uroplakine III (cellmarque AU-1 clone, 1:25) Chromogen (monosan clone 5H7,1:25) WT1 (novocastra, clone 3F-H2, 1:25) NSE (DAKO, clone BB5/NC/V1-H14, 1:50), CK20 (DAKO, clone Ks20.8, 1:50),CK7 (Zymed 1:25, clone V-TL12/30)were used. RESULTS: The mean age of the patients was 51.4 years ranging from 16 to 82 years. The tumor was unilateral in 28 cases (16/28 in the right ovary and 12/28 in the left ovary) and bilateral in two cases. Twenty-eight cases (93%) were benign and two (7%) were proliferating (borderline) tumors. Seventeen cases (56%) were pure Brenner tumors, measuring from 0.5 to 2.5 cm and 13 cases (44%) were mixed tumors consisting of a Brenner tumor element and a mucinous ovarian tumor (10/13 cases, 53.8%) and a germ cell tumor in 3/13 cases. The largest diameter of the mixed tumors ranged from 7 to 22 cm. The largest area consisting of Brenner elements measured 7 cm. The immunoprofile of Brenner tumor cell was cytokeratine-7 positive (30/30 cases) cytokeratine-20 negative in the Brenner cell element but positive in the mucinous component in 5/7 cases of mixed Brenner tumors, focally WT-1 positive (5/30 cases), NSE negative (0/30 cases) and focally chromogranine positive (6/30 cases), Uroplakin-III positive in 23/30 cases, with faint cytoplasmatic or luminal distribution. In conclusion, Brenner ovarian tumors are unilateral, small and benign neoplasms in their majority and present specific histopathological and immunopathological characteristics and mixed forms with other epithelial and germ cell neoplasms. This could be explained as a form of metaplasia or a diverse histogenesis from surface epithelium and/or the germ cell ovarian component.

The OV-TL 12/30 clone of anti-cytokeratin 7 antibody as a new marker of corneal conjunctivalization in patients with limbal stem cell deficiency.

PURPOSE: To present cytokeratin (CK)7 (OV-TL 12/30 clone) as a newly identified, reliable marker for distinguishing between the conjunctival and corneal surface epithelia, which will contribute to the precise diagnosis of limbal stem cell deficiency (LSCD). METHODS: Corneal and conjunctival epithelial imprints from 12 cadaveric bulbi and from 9 patients with clinically diagnosed LSCD were used for CK7 and CK19 immunocytochemistry. Specimens on nitroacetate cellulose filter papers obtained from the patients were stained with a combination of periodic acid-Schiff (PAS) and Gill's modified Papanicolaou stains, to assess the presence of goblet cells (GCs). RESULTS: CK7 was present in almost all superficial conjunctival epithelial cells from the cadaveric specimens. No immunostaining was observed on the corneal surface. A prominent sharp border of stain was found between the positive conjunctiva and the completely negative epithelium of the central cornea. A more gradual centrifugal decrease in the number of positive cells between the conjunctiva and cornea was observed for CK19. Several CK19-positive cells were detected in the central corneal epithelium. All corneal specimens from affected eyes (unilateral as well as bilateral LSCD patients) revealed strong positivity for CK7, and GCs were present in only 78% of patients. CONCLUSIONS: In cases in which GCs are severely decreased or are absent from the conjunctival surface, the detection of CK7 (OV-TL 12/30 clone) clearly confirms the overgrowth of the conjunctival epithelium over the cornea. Moreover, CK7 is a more reliable marker for distinguishing between the corneal and conjunctival epithelia compared with CK19.

Prognostic impact of regional lymph node micrometastasis in patients with node-negative biliary cancer.

OBJECTIVE: To immunohistochemically identify regional lymph node micrometastases in patients with regional node-negative biliary cancer who underwent curative resection, and to evaluate their clinical significance. SUMMARY BACKGROUND DATA: The clinical significance of immunohistochemically detected lymph node micrometastasis has recently been evaluated in various tumors. However, few reports have focused on this issue with regard to biliary cancer. METHODS: A total of 1421 regional lymph nodes from 151 patients with biliary cancer with negative regional nodes (as determined by conventional methods) were immunostained with antibody against cytokeratins 7 and 8 (CAM5.2). Prognostic impact was evaluated among patients with no metastasis, micrometastasis, and obvious metastasis detected by hematoxylin and eosin staining. Immunostained tumor foci were classified as small micrometastasis or large micrometastasis according to size (above or below 0.2 mm). RESULTS: CAM5.2-positive occult carcinoma cells in regional lymph nodes were detected in 33 (22%) of 151 patients and 49 (3%) of 1421 regional lymph nodes. Small micrometastases were detected in 23 patients, whereas large micrometastases were found in 10 patients. Survival for patients with micrometastasis was significantly worse than that for patients without (P = 0.0051), but was significantly better than that for patients with overt metastasis (P = 0.0092). No significant difference in postoperative survival was seen between patients with small and large micrometastases (P = 0.4221). CONCLUSIONS: Occult cancer cells were present in regional lymph nodes of 22% patients with regional node-negative biliary cancer, and were associated with significantly worse survival. Patients with micrometastases should be treated as carefully as node-positive patients.

The diagnostic value of cytokeratins expression in the renal parenchyma tumors.

Renal carcinomas are a heterogeneous group of tumors, difficult to classify and identify precisely. Since their prognosis depends very much upon their type, precise diagnosis might mean the difference between therapeutic success and patient death. Cytokeratins are particularly useful for the identification of the epithelial nature of the tumors, because their expression is maintained even in poorly differentiated tumors. Monoclonal cytokeratins such as CK7 and CK20 stain different components of the renal tubular system and are a useful duo for the identification of the origin of the different tumors that might arise in the kidney. Along with polyclonal cytokeratins such as AE1/AE3 and high molecular weight cytokeratin antibodies (34betaE12, Cam 5.2), epithelial membrane antigen (EMA) and vimentin, they are included in every diagnostic panel for renal tumors. We have selected 138 renal parenchyma tumor specimens, performed morphological diagnosis and then stained them with polyclonal cytokeratin antibody AE1/AE3, and monoclonal antibodies to CK7 and CK20. AE1/AE3 was expressed in 61.7% of the renal parenchyma tumors, with high intensity and percentage of positive cases in the papillary carcinomas (100%), and with rare and weakly positive cells in chromophobic cells carcinomas, clear cells carcinomas and sarcomatous carcinomas. CK7 was positive in 68% of the renal parenchyma tumors, with positive reaction in 100% of the cases of chromophobic cells and sarcomatous carcinomas. Clear cells carcinomas had the less percentage of positive cells, whereas papillary carcinomas were positive in seven out of eight cases. No difference in the staining pattern was noticed between type I and type II papillary carcinomas. CK20 was negative in all cases studied.

Is histological diagnosis of primary liver carcinomas with fibrous stroma reproducible among experts?

AIMS: In the era of targeted therapeutics, histological typing of hepatobiliary carcinomas has major clinical implications. Little is known about the reproducibility of the pathological diagnosis of primary liver carcinomas. Therefore, this study aimed to evaluate the worldwide variation in the pathological expert diagnoses of primary liver carcinomas with fibrous stroma in patients who did not have cirrhosis. METHODS: A single set of slides was selected from 25 tumours, and this set was reviewed independently by 12 pathologists who have worldwide expertise in liver tumours. Reproducibility of the diagnoses was evaluated by Light's kappa, and diagnoses were clustered by multidimensional scaling. Immunohistochemistry was performed after histological review. RESULTS: The interobserver reproducibility for diagnosis of hepatocellular carcinoma subtypes and cholangiocarcinomas was poor (kappa 0.23-0.52), even when the experts considered that the diagnosis required no additional stains or clinical information. Interestingly, multidimensional scaling revealed three main clusters of tumours: hepatocellular carcinoma with no other specifications (n = 13), fibrolamellar hepatocellular carcinoma (n = 3) and cholangiocarcinoma (n = 9). Using immunohistochemistry, these histological clusters correlated with expression of anti-hepatocyte and anti-cytokeratin 19 (p<0.001). CONCLUSIONS: The results demonstrate the poor reproducibility among experts of the pathological diagnosis of primary liver carcinomas with fibrous stroma in patients who did not have cirrhosis, and highlight that the systematic use of immunohistochemistry may improve the diagnostic accuracy.

Histological diversity in basaloid squamous cell carcinoma of the esophagus.

Basaloid squamous cell carcinoma of the esophagus (BSCCE) is a distinct variant of esophageal cancer. This study investigated histopathological variations of BSCCE. Thirty-eight surgical and two endoscopically resected specimens of BSCCE were examined. Histological features were classified into five components: solid nest (SN), microcyst and/or trabecular nest (MT), ductal differentiation (DD), cribriform pattern (CP), and an invasive squamous cell carcinoma (SCC) component. The immunohistochemical phenotypes of each component were examined using antibodies against cytokeratin (CK) 7, CK14, and alpha smooth muscle actin (SMA). SN, MT, DD, CP, and SCC were present in 95.0, 97.5, 27.5, 32.5, and 82.5% of the cases, respectively, and combinations of SN & MT, SN & DD, SN, MT & DD, SN, MT & CP, and SN, MT, DD & CP were found in 50.0, 2.5, 10.0, 17.5, and 15.0%, respectively. All the intraepithelial lesions observed in 18 (45.0%) cases were SCC. Immunoreactivity for CK7, CK14, and SMA was seen in 10.5, 86.8, and 18.4% of SN; 30.8, 97.4, and 38.5% of MT; 54.5, 100.0, and 54.5% of DD; 7.7, 76.9, and 23.1% of CP; and 6.1, 97.0, and 0.0% of SCC, respectively. CK14 immunoreactivity was seen in the periphery of most of the SN component. CK7, CK14, and SMA immunoreactivity was seen in the inner layer, all layers, and the outer layer of DD, respectively. MT and CP showed partial peripheral positivity for CK14 and SMA in microcystic, trabecular, and cribriform-like pseudoglandular structures. BSCCE demonstrates various histopathological and immunohistochemical features including a ductal and cribriform growth pattern.

[Immunohistochemical profile of colorectal and ovarian carcinomas--examination with cytokeratin 7, cytokeratin 20, beta catenin and cDX 2].

INTRODUCTION: Metastases from colorectal adenocarcinomas can be histologically similar to serous, mucinous and endometrioid ovarian adenocarcinomas. The differentiation between primary and metastatic ovarian tumours is of great importance for the patients because of the different treatment and prognosis. AIM: The aim of the study was to determine whether the differences in the expression of Cytokeratin 7, Cytokeratin 20, Beta catenin and CDX2 can be used to distinguish the different types of carcinomas and their metastases. MATERIALS AND METHODS: The immunohistochemical expression of the listed above antibodies was examined retrospectively and prospectively in 38 colorectal adenocarcinomas (primary and metastatic) and 32 ovarian adenocarcinomas (primary and metastatic). The metastases in both types of adenocarcinomas are located in the peritoneum. RESULTS: The immunohistochemical expression was evaluated using a semi-quantitative method. The ovarian adenocarcinomas are mostly positive for Cytokeratin 7 (in 63%), while colorectal carcinomas are mostly positive for Cytokeratin 20 (in 73%). Regarding Beta catenin, in colorectal carcinomas the expression is mostly nuclear (in 65%) and in ovarian carcinomas mostly membrane (in 68%). In cases of uncertain expression of the markers mentioned above, CDX2 was used. Positive nuclear expression was observed only in intestinal tumours (in 86%). CONCLUSION: For differential diagnosis between ovarian and colorectal adenocarcinomas, the use of antibodies, determining the intestinal differentiation of the tumours like Cytokeratin 20, Beta catenin and CDX2 is recommended.

Immunohistohemical evidences of pregnancy in uterine curettage tissue by the use of a double immunocytochemical staining technique using cytokeratin 7 and vimentin antibodies.

BACKGROUND/AIM: Usual histopatological diagnosis of intrauterine pregnancy is made by demonstration of chorionic villi, but in the curettage tissue from intrauterine miscarriage they may not be present in all cases. The use of monoclonal antibody against cytokeratin as a sensitive and reliable marker for the morphologic discrimination between invasive trophoblastic (IT) cells and decidual cells has been well established. The aim of this study was to determine the presence of pregnancy in endometrial curettings when chorionic villi are absent from patients suspected of intrauterine pregnancy. METHODS: Twenty cases of endometrial tissue specimens were investigated for cytokeratin and vimentin expression by a double immunostaining for detection of IT cells. RESULTS: Out of the total number of cases (20) 17 cases expressed cytokeratin 7 positive IT cells, that are an evidence of pregnancy. CONCLUSION: The obtained results indicated, that double immunohistochemical demonstration of cytokeratin and vimentin is useful for identifying pregnancy in all chorionic villi-negative cases.

Usefulness of cytokeratin immunoreactivity pattern for distinction of Barrett's esophagus from intestinal metaplasia of the stomach.

The histological distinction between Barrett's esophagus involving the distal esophagus and intestinal metaplasia of the stomach has important clinical implications and can be difficult even with the use of histochemical stains. Cytokeratin (CK) 7 and 20 are cytoplastic structural proteins that show restricted expression in normal and malignant epithelia of the gastrointestinal tract. CK7 and 20 immunostaining were performed on a 67-year-old male with cardiac cancer with reflux esophagitis due to sliding hernia. The CK7/20 immunoreactivity pattern of cancer and reflux esophagitis in this case showed superficial CK20 staining and strong CK7 staining of both superficial and deep glands. In intestinal metaplasia of the stomach, strong CK20 immunostaining in superficial and deep glands and absent CK7 immunoreactivity were noted. Neither CK7 nor CK20 immunoreactivity was noted in squamous cell epithelium. Therefore, we concluded that in this patient intestinal metaplasia of the esophagus was BE. The CK7/20 reactivity pattern is useful for identifying the intestinal metaplasia of the esophagus from the stomach using histological materials from biopsy and surgically resected specimens.