Füsun Düzcan

No Strong Association Between HER-2/neu Protein Overexpression and Gene Amplification in High-grade Invasive Urothelial Carcinomas

The generation of urothelial carcinoma is caused by the accumulation of various molecular changes, as in most malignancies. There are conflicting data about the status of HER-2/neu oncogene in urothelial carcinomas. The aim of this study was to determine the status of HER-2/neu oncogene in high-grade invasive urothelial carcinoma of urinary bladder both in protein and DNA level. We evaluated HER-2/neu protein overexpression by immunohistochemistry (IHC) and gene amplification by fluorescent in situ hybridization (FISH) and real-time quantitative PCR in paraffin-embedded samples of high-grade invasive urothelial carcinoma obtained from 36 patients. Polysomy 17 was also assessed by FISH. Immunohistochemically, HER-2/neu protein overexpression was observed in 22 (61.1%) tumors (ten tumors with score 3+ and 12 with score 2+). Fourteen of 36 tumors (38.9%) were evaluated as negative (score 0 or 1+). Complete concordance between FISH and the PCR was seen in all of the samples scored as 0 and 1+ by IHC. HER-2/neu gene amplification was observed in three of 27 (11.1%) tumors by FISH (nine samples were non-informative) and in eight of 36 (22.2%) tumors by the PCR. The complete concordance between HER2-2/neu protein overexpression and gene amplification was seen only in three of 27 tumors. Polysomy 17 was seen in nine tumors (33.3%). The results indicated that, in contrast to breast cancer, there was no strong association between HER-2/neu overexpression and gene amplification in invasive urothelial carcinomas, and polysomy 17 was higher in tumors showing HER-2/neu overexpression.

Cytogenetic studies in patients with reproductive failure

Acta Obstet Gynecol Scand 2003; 82: 53–56.

The Role of RELN in Lissencephaly and Neuropsychiatric Disease

Reelin is an extracellular matrix‐associated protein important in the regulation of neuronal migration during cerebral cortical development. Point mutations in the RELN gene have been shown to cause an autosomal recessive human brain malformation termed lissencephaly with cerebellar hypoplasia (LCH). Recent work has raised the possibility that reelin may also play a pathogenic role in other neuropsychiatric disorders. We sought, therefore, to define more precisely the phenotype of RELN gene disruption. To do this, we performed a clinical, radiological, and molecular study of a family in whom multiple individuals carry a chromosomal inversion that disrupts the RELN locus. A 6‐year‐old girl homozygous for the pericentric inversion 46,XX,inv7(p11.2q22) demonstrated the same clinical features that have been previously described in association with RELN point mutations. The girls brain magnetic resonance imaging (MRI) findings, including pachygyria and severe cerebellar hypoplasia, were identical to those seen with RELN point mutations. Fluorescence in situ hybridization confirmed that one of the breakpoints of this inversion mapped to within the RELN gene, and Western blotting revealed an absence of detectable serum reelin protein. Several relatives who were heterozygous for this inversion were neurologically normal and had no signs of psychotic illness. Our findings demonstrate the distinctive phenotype of LCH, which is easily distinguishable from other forms of lissencephaly. Although RELN appears to be critical for normal cerebral and cerebellar development, its role, if any, in the pathogenesis of psychiatric disorders remains unclear.

Familial influence on parkinsonism in a rural area of Turkey (Kızılcaboluk–Denizli): A community-based case-control study

This population‐based study on parkinsonism in a genetically isolated community from a rural area of Turkey aimed to provide a selective evaluation of environmental and heritable risk factors. An increased prevalence of parkinsonism (4.1%) was detected in the village of Kızılcaboluk for people 65 years of age and older. This study included 36 patients with parkinsonism living in Kızılcaboluk and three times that number of age‐ and sex‐matched people serving as controls. A questionnaire including demographic data, family history, education, occupation, data on exposures to pesticides, smoking, alcohol intake, and head trauma was administered. We found a significant association of parkinsonism cases with a positive family history in first‐degree relatives (odds ratio [OR], 7.48; 95% confidence interval [CI], 2.52–22.17; P < 0.0001) and with pesticide exposure (OR, 2.96; 95% CI, 1.31–6.69; P = 0.015) compared to the control subjects. The value of genetically isolated populations for the identification of genetic risk factors for common and complex disorders has gained much attention recently because the genetic make‐up of these populations is likely to be less complex than that of the general population and our findings should prompt investigations to the nature of a familial aggregation of parkinsonism in this population.

Progressive autosomal dominant optic atrophy and sensorineural hearing loss in a Turkish family

Purpose: To describe the clinical features, mode of inheritance, and linkage analysis of ten affected members of a three-generation family with progressive optic atrophy and progressive hearing loss. Materials and methods: The proband, a 10-year-old boy, presented with progressive visual failure. Ten other members in his family, including his mother, half-sister, aunt, two uncles, grandfather, and some of the cousins, also had progressive visual loss and hearing loss. Six affected and four unaffected cases were examined in detail. Blood samples were drawn from 16 members for DNA extraction. Two loci previously described for optic atrophy were tested for linkage in the present family. Results: The mode of inheritance was clearly autosomal dominant. Six members of the family were found to have progressive optic atrophy and hearing loss, both starting in the first decade of life. Total or red-green color blindness was detected in some patients. None of the members of this family showed evidence of other systemic disorders; however, four had blepharochalasis. No other cause could be found for the hearing or the visual loss. Linkage analysis excluded OPA1 and OPA2. Conclusion: The present Turkish family belongs to the group of individuals with autosomal dominantly inherited optic atrophies with hearing loss. Linkage analysis excluded OPA1 and OPA2, indicating that a novel gene defect underlies the disease in this family. Further genome-wide linkage analysis and identification of the disease-associated gene will help define the pathophysiology of this syndrome.

Expression and Amplification of Topoisomerase-2α in Type 1 and Type 2 Papillary Renal Cell Carcinomas and Its Correlation with HER2/neu Amplification

The current study was undertaken to investigate chromosomal and genetical aberrations leading to overexpression of Topoisomerase-2α (TOP2α) and to reveal the possible association of these aberrations with HER2/neu overexpression and gene amplification, and to search for the relationship between TOP2α and HER2/neu status with prognostical biomarkers in papillary renal cell carcinoma (RCC), a group of tumors with diverse molecular, chromosomal and clinical features. Archival cases of papillary RCC obtained from Departments of Pathology of Pamukkale, Ege and Dokuz Eylul Universities were studied in two groups (type 1 and type 2) each containing 20 cases. The level of TOP2α and HER2/neu expression by tumor cells were determined immunohistochemically. A multicolor FISH probe was used to define both amplification of HER2/neu and TOP2α genes, and polysomy 17. The ratio of cells expressing TOP2α in type 1 and type 2 papillary RCC were 24.29% and 6.89%, respectively. The difference was statistically significant comparing the average or median values of groups separately (p = 0.002). The expression levels of TOP2α and HER2/neu were also correlated. TOP2α and HER2/neu were co-amplified in both groups. Immunohistochemical expression was not observed in 15 of 23 cases with HER2/neu amplification. The most frequent finding detected by FISH method was polysomy of chromosome 17. We had contradictory results compared with the findings reported in the limited numbers of literature. It shows us that papillary RCC constitute a heterogenous group of tumors with various cytogenetic features and morphological classification of these tumors may not be compatible with their molecular characteristics.

Determination of apoptosis, proliferation status and O6-methylguanine DNA methyltransferase methylation profiles in different immunophenotypic profiles of diffuse large B-cell lymphoma

OBJECTIVE Our aim was to investigate the expression of apoptosis-associated proteins (bcl-2, bcl-xl, bax, bak, bid), apoptotic index (AI) and proliferation index (PI) in germinal center B-cell-like immunophenotypic profile (GCB) and non-GCB of diffuse large B-cell lymphoma (DLBCL). METHODS The methylation status of the promoter region of O6-methylguanine-DNA yerine O6-methylguanine-DNA methyltransferase (MGMT) gene and its relation with immunophenotypic differentiation of DLBCLs were also investigated. 101 cases were classified as GCB (29 cases) or non-GCB (72 cases). Apoptosis-associated proteins and PI were determined by IHC, and TUNEL method was used to determine AI. MGMT methylation analysis was performed by real-time PCR. RESULTS The PI was significantly higher in GCB compared with non-GCB (p=0.011). Percentage of cells stained with bcl-6 was positively correlated with the percentage of cells expressing bcl-2 (p=0.023), AI (p=0.006) and PI (p<0.001), while a significant negative correlation was observed with the percentage of cells expressing bax (p=0.027). The percentage of cells stained with MUM1 showed a significantly positive correlation with the percentage of cells expressing bcl-xl (p=0.003), bid (p=0.002), AI (p<0.001), and PI (p=0.001). MGMT methylation analysis was performed in 95 samples, and methylated profile was found in 31 cases (32.6%). GCB was found in 6 cases (22.2%) and non-GCB was determined in 25 cases (36.8%) out of 31 with MGMT methylated samples. There was no significant association between MGMT methylation status and immunophenotypic profiles (p=0.173). CONCLUSION These results suggest that bcl-6 protein expression may be responsible for the high PI in GCB. Additionally, we found that apoptosis-associated proteins were not significantly associated with immunophenotypic profiles.

Fatal Pulmonary Embolism Due to Inherited Thrombophilia Factors in a Child With Wolfram Syndrome.

Wolfram syndrome-1 is a rare and severe autosomal recessive neurodegenerative disease characterized by diabetes mellitus (DM), optic atrophy, diabetes insipidus, and deafness. Poorly controlled type 1 DM increases the risk for thrombosis. However, coexistence of DM and hereditary thrombosis factors is rarely observed. Here we present the case of a 13.5-year-old, nonfollowed girl newly diagnosed with poorly controlled Wolfram syndrome on the basis of the results of clinical and laboratory examinations. On the eighth day after diabetic ketoacidosis treatment, pulmonary embolism developed in the subject. Thrombus identified in the right atrium using echocardiography was treated by emergency thrombectomy. Homozygous mutation in the methylenetetrahydrofolate reductase gene C677T, heterozygous factor-V Leiden mutation, and active protein C resistance were identified in the patient. The patient was lost because of a recurring episode of pulmonary embolism on the 86th day of hospitalization. We present this case to highlight the need for investigating hereditary thrombosis risk factors in diabetic patients in whom thromboembolism develops.