Browsing by Author "Müller, G.A. (35467521800)"

Aims and background: The aim of this study was to determine the expression of cadherins and integrins in renal cell carcinoma (RCC) and their relationship with tumor morphology and TNM status. Methods: Cadherin and integrin expression was investigated using an indirect immunoperoxidase technique, applying antibodies to E-, N-, P- and VE-cadherin and to α1, α2, α3, α4, α5, α6, and αv integrin subunits. Correlation of semiquantitatively scored adhesion molecule levels with histopathological parameters (cytology, growth pattern, nuclear grade) and TNM status was performed for 24 RCCs (17 clear cell, 3 granular, 3 spindle cell and 1 chromophobe cell type according to the WHO classification). Results: E-cadherin and N-cadherin were present in most cases (88% and 67%, respectively) and were usually coexpressed. T3 RCCs displayed higher E-cadherin and N-cadherin levels than T1/T2 tumors regardless of tumor grade, suggesting that impairment of their function might exist without actual loss from tumor cells. P-cadherin was found focally in two RCCs only, while VE-cadherin was present on stromal vessel endothelium in five tumors, showing no differences with regard to cell type, growth pattern, tumor grade or TNM status. All integrins were present in the studied RCCs (ranging from 12% for α5 to 79% for α3), including those that are normally absent from adult kidney tissue (α4 and α5). Tumors of higher grade showed increased αv and decreased α6 levels, while RCCs with metastases less often showed diffuse α3 presence and never expressed α5 integrin. Conclusions: Our results suggest that the level of expression of N-cadherin and some integrins (most notably α3, α6 and α5) is associated with the capacity of RCC for local and distant spread, regardless of tumor grade.

Aims and background: The aim of this study was to determine the expression of cadherins and integrins in renal cell carcinoma (RCC) and their relationship with tumor morphology and TNM status. Methods: Cadherin and integrin expression was investigated using an indirect immunoperoxidase technique, applying antibodies to E-, N-, P- and VE-cadherin and to α1, α2, α3, α4, α5, α6, and αv integrin subunits. Correlation of semiquantitatively scored adhesion molecule levels with histopathological parameters (cytology, growth pattern, nuclear grade) and TNM status was performed for 24 RCCs (17 clear cell, 3 granular, 3 spindle cell and 1 chromophobe cell type according to the WHO classification). Results: E-cadherin and N-cadherin were present in most cases (88% and 67%, respectively) and were usually coexpressed. T3 RCCs displayed higher E-cadherin and N-cadherin levels than T1/T2 tumors regardless of tumor grade, suggesting that impairment of their function might exist without actual loss from tumor cells. P-cadherin was found focally in two RCCs only, while VE-cadherin was present on stromal vessel endothelium in five tumors, showing no differences with regard to cell type, growth pattern, tumor grade or TNM status. All integrins were present in the studied RCCs (ranging from 12% for α5 to 79% for α3), including those that are normally absent from adult kidney tissue (α4 and α5). Tumors of higher grade showed increased αv and decreased α6 levels, while RCCs with metastases less often showed diffuse α3 presence and never expressed α5 integrin. Conclusions: Our results suggest that the level of expression of N-cadherin and some integrins (most notably α3, α6 and α5) is associated with the capacity of RCC for local and distant spread, regardless of tumor grade.

Immunohistochemical analysis of HLA class I antigens expression in 26 renal cell carcinomas (RCCs) - 18 clear cell, 6 granular and 2 chromophobe - was performed with indirect immunoperoxidase method. Results were correlated with extent and immunophenotype of tumor infiltrating mononuclear cells, histopathological (histology, cytology, grade, presence of necrosis) and clinical (tumor diameter, TNM classification) characteristics of RCC. 4 (15%) RCCs showed reduced HLA class I presence and this was associated with greater tumor diameter and more frequent T3,T4 and M1 stage. All tumors with altered HLA class I antigens expression were grade 2 or 3 and strong correlation with presence of necrosis (p=0.006) was noticed, while mononuclear cell infiltrates (especially CD8+ T lymphocytes) were less extensive compared to tumors with normal HLA class I level. Our results suggest more aggressive clinical behavior of RCCs with reduced HLA class I antigens expression, probably due to impaired cellular antitumor immune response.

Immunohistochemical analysis of HLA class I antigens expression in 26 renal cell carcinomas (RCCs) - 18 clear cell, 6 granular and 2 chromophobe - was performed with indirect immunoperoxidase method. Results were correlated with extent and immunophenotype of tumor infiltrating mononuclear cells, histopathological (histology, cytology, grade, presence of necrosis) and clinical (tumor diameter, TNM classification) characteristics of RCC. 4 (15%) RCCs showed reduced HLA class I presence and this was associated with greater tumor diameter and more frequent T3,T4 and M1 stage. All tumors with altered HLA class I antigens expression were grade 2 or 3 and strong correlation with presence of necrosis (p=0.006) was noticed, while mononuclear cell infiltrates (especially CD8+ T lymphocytes) were less extensive compared to tumors with normal HLA class I level. Our results suggest more aggressive clinical behavior of RCCs with reduced HLA class I antigens expression, probably due to impaired cellular antitumor immune response.

Cryostat sections of 37 renal cell carcinomas (RCC) - 25 clear cell type, 10 granular and 2 chromophobe - were studied with indirect immunoperoxidase method applying monoclonal antibodies (MoAb) to HLA-DR, -DP and -DQ antigens for analysis of HLA class II antigens, and anti-CD14, - CD3, -CD4 and -CD8 MoAb for tumor infiltrating mononuclear cells (TIM). Number of positive cells was estimated semiquantitatively and results of immunohistochemical investigation were correlated with clinical (patient age and sex, tumor size and TNM stage) and histopathological (cytology, histology, grade) characteristics of RCC. All RCC expressed HLA-DR, 92% -DQ and 73% -DP antigens with level of expression in hierarchy DR>-DQ>-DP, but no statistically important correlation could be established with any of the histopathological or clinical parameters analyzed. Monocytes were more abundant than T lymphocytes and CD4+ than CD8+ T cells, whereas tumors with T lymphocyte predominance and approximately equal number of CD4+ and CD8+ T cells had greatest average diameter. Inadequate activation oft lymphocytes by tumor cells (despite capability of antigen presentation) could be the reason for association of parameters which indicates more aggressive tumor behavior with aberrant HLA class II antigen expression on RCC.

Cryostat sections of 37 renal cell carcinomas (RCC) - 25 clear cell type, 10 granular and 2 chromophobe - were studied with indirect immunoperoxidase method applying monoclonal antibodies (MoAb) to HLA-DR, -DP and -DQ antigens for analysis of HLA class II antigens, and anti-CD14, - CD3, -CD4 and -CD8 MoAb for tumor infiltrating mononuclear cells (TIM). Number of positive cells was estimated semiquantitatively and results of immunohistochemical investigation were correlated with clinical (patient age and sex, tumor size and TNM stage) and histopathological (cytology, histology, grade) characteristics of RCC. All RCC expressed HLA-DR, 92% -DQ and 73% -DP antigens with level of expression in hierarchy DR>-DQ>-DP, but no statistically important correlation could be established with any of the histopathological or clinical parameters analyzed. Monocytes were more abundant than T lymphocytes and CD4+ than CD8+ T cells, whereas tumors with T lymphocyte predominance and approximately equal number of CD4+ and CD8+ T cells had greatest average diameter. Inadequate activation oft lymphocytes by tumor cells (despite capability of antigen presentation) could be the reason for association of parameters which indicates more aggressive tumor behavior with aberrant HLA class II antigen expression on RCC.