Survivin, caspase-3 and MIB-1 expression in astrocytic tumors of various grades.

PURPOSE: Gliomas are the most common primary brain tumors. The etiology is still unclear and the progression from low to high-grade gliomas is frequent. The molecular mechanisms are quite established, however the heterogeneity of glioblastomas force the scientist to look for the new therapeutic targets. The aim of the study was to evaluate the caspase-3 and survivin expression in correlation with MIB-1 expression in gliomas of various grade to assess the apoptosis in gliomas and to determinate new possible targets for the future therapy. MATERIAL AND METHODS: We identified 131 patients with a histopathological diagnosis of astrocytic tumors (diffuse astrocytoma, anaplastic astrocytoma and glioblastoma). The evaluation of caspase-3, survivin and MIB-1 expression was done using immunohistochemical methods. RESULTS: Caspase-3 and survivin expression was observed both in low- and high-grade astrocytomas. The differences in expression were the most evident in glioblastoma group. All primary glioblastomas (31 cases) expressed caspase-3. In secondary glioblastoma group only 17 out of 30 specimens were positive for caspase-3. Survivin expression was observed in 80.6% primary glioblastomas and in all examined secondary glioblastomas and the staining was strong and diffuse in all cases. MIB-1 expression was low in diffuse astrocytomas (DA) and ranged between 1 and 5%. In anaplastic astrocytoma group it was ranged between 5 and 10% and the highest percentage of the positive cells was observed in glioblastoma cases and ranged from 10% even to 30%. The most evident MIB-1 expression was observed in the cells surrounding the pathological blood vessels and necrosis. CONCLUSIONS: The high incidence of survivin and caspase-3 expression in diffuse and anaplastic astrocytoma cases may suggest, that the regulation between pro- and antiapoptotic proteins may play an important role in tumor growth and progression. The overexpression of survivin and MIB-1 expression in glioblastoma cases also may confirm the theory about the important role of anti-apoptotic and proliferation processes in glioblastoma progression and as such may be potential therapeutic targets.

Assessment of S100 protein expression in the epididymis of juvenile and adult European bison.

In our study, we decided to compare S100 protein expression in the material obtained from the epididymes of 5- and 12-month-old calves, and adult European bison, and to detect any differences in S100 expression according to the animal age and size of the organ examined. We used the epididymes obtained from 6 adult European bison aged 6-12 years, from 6 at the age of 12 months and 6 calves aged 5 months. Immunocytochemical reactions were performed using the avidin-biotinylated-peroxidase (ABC) technique according to HSU. Specific polyclonal rabbit antiserum against bovine S100 protein (Bio Genex Laboratories) at a dilution at 1:400 was applied. We found the expression of S100 protein in endothelial cells of arteries, veins and lymphatic vessels in all the study animals. At the same time, we found no differences in the expression of S100 protein in vascular endothelial cells. Our observations seem to indicate that S100 expression in endothelial cells of European bison epididymis is not correlated with age or maturity of the organ tested. We found S100 protein in smooth muscle cells of arteries and veins in all European bison specimens examined. Interestingly in the current study, in young 5-month-old sexually immature European bison specimens we observed weaker expression of S100 protein in smooth muscle cells of small vessels as compared to the same cell type both in large vessels in these animals and in small vessels in adult specimens.

Assessment of expression of selected Bcl-2 family proteins in lymphoid infiltration in patients with B-cell chronic lymphocytic leukaemia treated with nucleoside analogues.

B-cell chronic lymphocytic leukaemia (B-CLL) is characterized by clonal growth and accumulation of mature lymphoid cells due to disturbance in genetically regulated form of cell death called apoptosis. The intrinsic mechanism of apoptosis is controlled by Bcl-2 family proteins. Purine nucleoside analogues induce the apoptosis in cells in a state of quiescence. The aim of the study was to assess expression of selected Bcl-2 family proteins in neoplastic infiltration in bone marrow in patients with B-CLL treated with nucleoside analogues. The study comprised examination of bone marrow obtained routinely by trephine biopsy from 18 patients with B-CLL diagnosed before administration of purine nucleoside analogues treatment and after its completion. Expression of Bcl-2, Bcl-x and Bax proteins was examined. Lymphoid cells in bone marrow were present in all patients before administration of treatment. After treatment in two patients bone marrow was infiltrated in diffuse pattern, whereas other patients presented nodular pattern of infiltration. The difference between stage of infiltration before and after treatment was statistically significant (p<0.002). High percentage of infiltration cells with positive anti Bcl-2 reaction from 42.0% in one patient to 85.33+/-3.06% in four patients before treatment was observed. After treatment percentage of infiltration cells with positive anti Bcl-2 antibody reaction was from 33.0+/-18.38% in two patients to 99.0% in one patient. Positive correlation between stage of infiltration and expression of Bcl-2 protein was confirmed before and after treatment. Such correlations were not observed in case of Bax and Bcl-x. Strong staining of immunohistochemical reaction of cells in lymphoid infiltration with Bcl-2 antibody was confirmed. There was a difference between Bcl-/Bax ratio before and after treatment. Immunohistochemical assessment of expression of Bcl-2 family proteins in cells of lymphoid infiltration in bone marrow of patients with CLL is an important method in detection of minimal residual disease (MRD) after treatment.

Angiogenesis in gliomas.

Brain gliomas are characterized by invasive growth and neovascularisation potential. Angiogenesis plays a major role in the progression of gliomas and its determination has a great prognostic value. The aim of the study was to assess the vascularisation of chosen brain gliomas and to estimate how it is correlated with tumour histological type, malignancy grade, location and size, and with age and sex of patients. Tumour vascularisation analysis was based on the determination of microvascular proliferation (MVP) and microvessel density (MVD). Microvascular proliferation was measured with immunohistochemical methods using mouse monoclonal antibodies to detect cell proliferation antigens. The following antibodies were used Ki-67 and PCNA (DAKO). Identification of vessels was performed by CD31 antibody and anti-human von Willebrand factor (DAKO). The highest microvascular proliferation and microvascular density were observed in multiform glioblastomas and the lowest in oligodendrogliomas. Significant correlation was observed between the vascularisation and malignancy grade.