Browsing by Author "Todorovic, V. (7006326762)"

Background: Actinic keratosis (AK) has been defined as a precancerous lesion or an early phase in the evolution of squamous cell carcinoma (SCC) and histological changes seen in the individual cells of an AK are indistinguishable from those seen in SCC, which invade the dermis. Cyclin A is an increasingly utilized proliferation marker that has functions in both S phase (DNA replication) and initiation of mitosis, whereas alterations of β-catenin, the molecule involved in cell-cell adhesion and in signalling transduction, could promote invasive and proliferative capacities of malignant tumours. Objectives: To determine cyclin A and β-catenin expression pattern in cutaneous SCC and in in situ lesions classified as keratinocytic intraepidermal neoplasia (KIN) and, using traditional terms, as AK and Bowen's disease (BD), and to analyse it in relation to SCC differentiation, diameter and thickness. Methods: Immunohistochemical staining was performed on 110 formalin-fixed paraffin-embedded tissue samples with the streptavidin-biotin technique using antibodies to cyclin A and β-catenin. On histological examination, 53 lesions were diagnosed as AK, 16 as BD and 41 as SCC-11 well differentiated (WD), 16 moderately differentiated (MD) and 14 poorly differentiated (PD). Using KIN classification, 22 lesions were KIN1, 23 were KIN2 and 24 were KIN3. For cyclin A, distribution and labelling index (LI), and for β-catenin, level of membranous staining and presence of aberrant (nuclear/cytoplasmic) localization were examined. Results: Diffuse cyclin A presence was observed more frequently in BD than in AK (P < 0.0001) or SCC (P = 0.0002), and in SCC-PD compared with SCC-WD (P < 0.0001) or SCC-MD (P = 0.0003). Differences between KIN3 and KIN2, as well as KIN3 and KIN1 lesions, were statistically significant (P < 0.0001), and the same result appeared when KIN1 and KIN 2 cases were grouped and compared with those of KIN3 (P < 0.0001). Cyclin A LI was significantly lower (P < 0.05) in AK than in BD or SCC, but no difference between BD and SCC was found, and U in BD was even higher than in SCC-WD or SCC-MD, while analysis regarding SCC differentiation and KIN classification revealed the same correlation as for the cyclin A distribution. Reduced or absent β-catenin membranous staining was found in 90 cases (81.8%), more often in SCC than in AK (P = 0.03) or in AK and BD grouped together (P = 0.02). There was no statistical difference between SCCs of various level of differentiation, or between different KIN grades. Diffuse loss of membranous β-catenin staining showed 36 lesions (32.7%), more frequently SCC than AK (P = 0.003) or AK and BD grouped (P = 0.006), as well as SCC-PD compared with SCC-WD (P = 0.01) and SCC-MD (P = 0.03), whereas all KIN comparisons remained nonsignificant. Aberrant β-catenin cellular localization demonstrated 28 lesions (25.5%), most often in the basal or peripheral parts and in the lesions with diffuse β-catenin loss (P = 0.009), but revealed no correlation with the histological type, SCC level of differentiation or KIN grades. Diffuse loss of membranous β-catenin staining was found to be significantly more frequent in SCC thicker than 4 mm (P = 0.03), while all other comparisons between cyclin A or β-catenin with the tumour size remained nonsignificant. Cyclin A LI was higher in cases with diffuse loss of membranous staining (P = 0.001) or with aberrant cellular localization of β-catenin (P = 0.002). Conclusions: Cyclin A LI showed greater difference between AK and BD than between BD and SCC, suggesting that increased proliferation (measured by cyclin A LI) characterizes progression of in situ lesions from AK to BD, whereas reduced β-catenin expression separates more clearly SCC from the in situ lesions. Diffuse pattern of loss of membranous β-catenin staining correlated better with the type of lesion, SCC differentiation and tumour size than reduced expression in general or aberrant cellular localization of β-catenin. KIN classification does not seem to be supported by our findings, except when KIN1 and KIN2 lesions (in situ, partial thickness) are grouped. © 2005 British Association of Dermatologists.

Morphometric methods were used to analyze the ultrastructural characteristics of peripheral blood polymorphonuclear neutrophils (PMN) in 10 rats chronically consuming ethanol and 20 rats fed an isoenergetic standard diet (10 ad libitum and 10 pair fed control rats). Morphometric measurements were made, after a 4-month experimental period, of the following: the profile area of the cell, nucleus and cytoplasm; nucleus to cell profile area; volume density of the nucleus, cytoplasm, mitochondria, Golgi system, endoplasmic reticulum and cytoplasmic granules; number of mitochondria per cell profile; number of cytoplasmic granules per cell profile and per μm2 of cytoplasm, as well as the azurophilic to specific granule ratio and mean diameter of granules. A significant decrease in cell profile area and cytoplasm profile area was shown in ethanol-treated rats. The volume density of mitochondria and endoplasmic reticulum nearly doubled during ethanol abuse. The results also showed that there were highly significant effects of ethanol on the total number of cytoplasmic granules per cell. In addition, changes were observed in mitochondria such as clumping, elongation, swelling and disruption of cristae, as well as changes in the topographic distribution of granules in the cytoplasm such as registration of cytoplasmic areas with numerous granules and areas with a smaller number or without any granules. Some neutrophils of ethanol-treated rats had autophagic vacuoles. The results indicate some ultrastructural abnormalities of PMN in chronic experimental alcoholism that may be related to polymorphonuclear phagocyte dysfunction.

Morphometric methods were used to analyze the ultrastructural characteristics of peripheral blood polymorphonuclear neutrophils (PMN) in 10 rats chronically consuming ethanol and 20 rats fed an isoenergetic standard diet (10 ad libitum and 10 pair fed control rats). Morphometric measurements were made, after a 4-month experimental period, of the following: the profile area of the cell, nucleus and cytoplasm; nucleus to cell profile area; volume density of the nucleus, cytoplasm, mitochondria, Golgi system, endoplasmic reticulum and cytoplasmic granules; number of mitochondria per cell profile; number of cytoplasmic granules per cell profile and per μm2 of cytoplasm, as well as the azurophilic to specific granule ratio and mean diameter of granules. A significant decrease in cell profile area and cytoplasm profile area was shown in ethanol-treated rats. The volume density of mitochondria and endoplasmic reticulum nearly doubled during ethanol abuse. The results also showed that there were highly significant effects of ethanol on the total number of cytoplasmic granules per cell. In addition, changes were observed in mitochondria such as clumping, elongation, swelling and disruption of cristae, as well as changes in the topographic distribution of granules in the cytoplasm such as registration of cytoplasmic areas with numerous granules and areas with a smaller number or without any granules. Some neutrophils of ethanol-treated rats had autophagic vacuoles. The results indicate some ultrastructural abnormalities of PMN in chronic experimental alcoholism that may be related to polymorphonuclear phagocyte dysfunction.

Immunomorphological characteristics of 27 renal cell carcinoma (RCC): 18 clear cell, 6 granular (chromophilic), 2 chromophobe, 1 spindle cell (sarcomatoid) as well as of 1 oncocytoma, were analyzed. The investigation was performed on cryostat sections by immunoperoxidase technique applying a panel of monoclonal antibodies which defined: proximal (TNE3, TN5, 5D9) and distal (TN8, TN9, 7C2) tubular antigens; intercellular adhesion molecule 1 (ICAM1); HLA class II (-DQ, -DR and -DP) antigens, intermediary filaments (cytokeratin and vimentin); and antigens on tumour infiltrating mononuclear leucocytes (TT1, TT2 and LeuM3 for CD4, CD8 and CD14 antigens, respectively). All RCC with exception of chromophobe co-expressed cytokeratin and vimentin. In addition, they were usually positive for all proximal and two distal tubular markers (TN8, TN9) indicating primitive cells which could differentiate into the epithelium of both parts of tubule system as the most probable originators of in RCC. Almost all RCC but the chromophobe aberrantly expressed HLA class II antigens which great variability from case to case. The presence of HLA-DR antigens was more intensive and widespread than of HLA-DQ and-DP antigens. Expression of ICAM 1 mostly correlated with presence of HLA class II antigens, particularly with -DR on tumour cells of RCC. HLA-DR antigen expression was always more prominent than mononuclear cell infiltrate (among which macrophages prevailed over T cells) which could suggest that increased histocompatibility antigen expression precedes mononuclear cell influx. In contrast to all other RCC, chromophobe tumours had quite distinct features revealing the most intense reaction with 7C2 (MAb that produced the weakest reaction with other tumour types), absence of vimentin and very weak reaction with antibodies for HLA class II Ag and ICAM 1. Since oncocytoma has similar immunohistological properties it could be supposed that both tumours have common histogenesis.

The effect of experimental protein malnutrition on gastrin producing cells in the antral part of the stomach was studied in male Wistar rats. Isoenergetic diets containing 25% (C-25) or 6% (PD-6) were given in isocaloric amounts during a 4-month experiment. All rats were offered drinking water ad libitum. The results showed that the long-term protein diet did not produce changes in the gastrin cell number. At the ultrastructural level G cells exhibited a decreased size of the nucleus. They were found to have an increased total granule volume density but the volume density of dense-cored granules was lower. The serum gastrin levels were significantly lowered by feeding the low protein diet. These changes are compatible with decreased functional activity of G cells under long-term protein deprivation.

The case of a 46-year-old female with umbilical metastasis as a first sign of an ovarian carcinoma is reported with the results of immunohistochemical analysis of primary tumor and lymph node and umbilical metastases. All specimens were positive for cytokeratin 7, CA 125, E-cadherin, alpha-, beta-, and gamma-catenin, as well as for MSH2. Staining with cytokeratin 20 and MLH1 was negative, and Ki-67 labeled from 5% (in the center of the lesions) to over 25% (at the periphery of the lesions) of the nuclei. Beta-catenin showed membranous positivity in the central parts and absence of staining at the periphery of ovarian tumor and umbilical metastasis, whereas lymph node metastasis presented with uniform reaction throughout. The results of immunohistochemical staining could point to the mechanisms employed by malignant tumors during invasion and growth of metastasis and suggest the possible role of the microenvironment in the expression of some adhesion molecules on tumor cells. © 2005 IGCS.