Despite the association of several miRNAs with bladder cancer, little is known about the miRNAs' regulatory networks. In this study, we aimed to construct potential networks of bladder-cancer-related miRNAs and their known target genes using miRNA expression profiling and bioinformatics tools and to investigate potential key molecules that might play roles in bladder cancer regulatory networks. Global miRNA expression profiles were obtained using microarray followed by RT-qPCR validation using two randomly selected miRNAs. Known targets of deregulated miRNAs were utilized using DIANA-TarBase database v6.0. The incorporation of deregulated miRNAs and target genes into KEGG pathways were utilized using DIANA-mirPath software. To construct potential miRNA regulatory networks, the overlapping parts of three selected KEGG pathways were visualized by Cytoscape software. We finally gained 19 deregulated miRNAs, including 5 ups- and 14 down regulated in 27 bladder-cancer tissue samples and 8 normal urothelial tissue samples. The enrichment results of deregulated miRNAs and known target genes showed that most pathways were related to cancer or cell signaling pathways. We determined the hub CDK6, BCL2, E2F3, PTEN, MYC, RB, and ERBB3 target genes and hub hsa-let-7c, hsa-miR-195-5p, hsa-miR-141-3p, hsa-miR-26a-5p, hsa-miR-23b-3p, and hsa-miR-125b-5p miRNAs of the constructed networks. These findings provide new insights into the bladder cancer regulatory networks and give us a hypothesis that hsa-let-7c, hsa-miR-195-5p, and hsa-miR-125b-5p, along with CDK4 and CDK6 genes might exist in the same bladder cancer pathway. Particularly, hub miRNAs and genes might be potential biomarkers for bladder cancer clinics.

To extend our understanding of potential stepwise genetic alterations that may underlie tumor progression from low-grade astrocytomas to glioblastomas, histopathologic and comparative genomic hybridization analyses were performed on tumor specimens from 68 primary lesions, including 40 glioblastomas, 10 anaplastic and 18 low-grade astrocytomas. The number of aberrations per case increased towards the higher grade tumors (grade II: 1.66+/-1.49; grade III: 2.80+/-1.68; grade IV: 3.02+/-1.07; F=6.955, p=0.002). A gain of 7/7q was common and the most frequently seen aberration in low-grade astrocytomas, whereas loss of 10q was the most frequently seen anomaly in anaplastic astrocytomas and glioblastomas. Chromosome 7p amplification was only detected in glioblastomas. Chromosome 10/10q deletion and combination of 1p, 19q and 17p deletions were specific to high-grade astrocytic tumors. Sequences of chromosome 7 and 10 seem to have pivotal roles in the biology of human gliomas. The genomic copy deletions of chromosomes 1p and 19q might provide an alternative mechanism in the genesis of astrocytomas.

Glial tumors are the most common tumors of the nervous system, affecting individuals at any age. Since understanding of the molecular pathologies underlying human gliomas is still very poor, the treatment and therefore prognosis of this malignancy could not yet be improved. In order to determine whether different glioblastoma-associated genomic aberrations may serve as prognostic markers in combination with histopathological findings, 20 primary glioblastoma multiforme tumors were screened by comparative genomic hybridization, and the results were compared with histopathological and clinical features. All tumors showed genomic copy aberrations detected by comparative genomic hybridization. Regional and numerical increases in chromosome 7 copy number were the most frequently seen abnormality (10/20 tumors), followed by loss of chromosome 10 (8/20). Both of these aberrations were associated with shorter surveillance time. Chromosome 12q amplification was detected in seven tumors. Loss of 17p, 1p, and 19q in combination was seen in three cases. One of them was a giant cell GBM, whereas the remaining two cases were still alive. Combination of chromosome 1p and 19q deletions was also seen in a case with long surveillance. According to the preliminary findings of this study, in addition to the EGFR gene, amplification of other genes on chromosome 7 and the deletion of PTEN gene and other cancer-related genes on chromosome 10 appeared important to the development of glioblastoma multiforme and were associated with poor prognosis, whereas the combination of chromosome 1p and 19q deletions seems to be an informative molecular marker for better prognosis. The clinical features and genetic alterations of primary and secondary glioblastoma multiforme should be compared in large series to clarify the effective prognostic markers; and further molecular analyses focused on chromosomes 7 and 10 will be very helpful for understanding the molecular mechanisms underlying the progression of glioblastoma.

In order to determine the incidence of confined placental mosaicism (CPM) in term placentae and to show the presence of specific sites and the effect on fetal development, 125 placentae from uneventful pregnancies were analysed by cytogenetic methods. The incidence was at least 4.8 per cent and there were no specific sites on the placenta. Although the number of cases is still too small, we found CPM to be associated with intrauterine growth retardation in six cases.

Previous studies have indicated a wide spectrum of incidences of 22q11.2 deletions in isolated and syndromic (sporadic or familial) cases of conotruncal heart defects, whereby the detection rate of the deletion varied from 65% in one study to 0 in another. We analysed 110 patients with non-selective syndromic or isolated non-familial congenital heart malformations by fluorescence in situ hybridization (FISH) using the D22S75 DiGeorge chromosome (DGS) region probe. A 22q11.2 microdeletion has been detected in 9/51 (17.6%) syndromic patients. Five were of maternal origin and four of paternal origin. None of the 59 patients with isolated congenital cardiac defect had a 22q11.2 deletion. We compared the cardiac anomalies of our patients with a 22q11.2 deletion with those of previously published series and we describe types of congenital heart defects which appear to be often associated with a 22q11.2 deletion. The ability to detect such types of heart defects and to provide an early diagnosis of 22q11.2 deletion is particularly relevant in very young infants, who often show only very mild expression of the otherwise well-characterized phenotypes of the DiGeorge/velo-cardio-facial syndrome (DG/VCFS).

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Little is known about genetic mutations during the malignant progression of spinal meningiomas. This study investigated genomic changes across the entire genome in spinal meningioma samples to determine possible mechanism(s) of tumorigenesis. Paraffin-embedded tissue sections of 16 spinal meningiomas were analyzed by the comparative genomic hybridization (CGH) technique. Lymphocytes of the patients were evaluated as controls. Genomic change was detected in 11 samples. Complete or partial loss of chromosome 22 was the most commonly seen abnormality in eight cases. Chromosome losses on 1p, 9p, and 10q and gains on 5p and 17q were the other abnormalities. These changes are all frequently seen in meningiomas, but are mostly specific to atypical and anaplastic meningiomas. However, in the present study, copy number changes on chromosomes 9p (3 samples), 17q (2 samples), and 1p (2 samples) were seen even in the benign tumors. Our results suggest that in addition to the neurofibromatosis type 2 tumor suppressor gene, other cancer-related genes located on 1p, 9p, 10q, and 17q might be involved in the etiology of spinal meningiomas.

Background Deletion of 13q14 [del(13q)] is the most common cytogenetic change (50%) in chronic lymphoblastic leukemia (CLL), and it is a good prognostic factor if it is detected as a sole aberration by FISH. However, it is observed the clinical course of CLL cases with del(13q) are quite heterogeneous and the responsible for this clinical heterogeneity has not been established yet. Some investigators suggest type II deletion (include RB1 gene) is associated with more aggressive clinical course. Also, it is suggested that the deletion burden and the deletion type have a prognostic effect. In this study, we aimed to investigate the effect of RB1 gene deletion, deletion burden and deletion type on overall survival (OS), disease stage and time to first treatment (TTFT) in patients with isolated del(3q). Sixty eight cases, detected isolated del(13q) were included in the study. Also, RB1 deletion was analyzed from peripheral blood of them using FISH. Results RB1 deletion was detected in 41% of patients, but there was no statistically significant difference between RB1 deletion and TTFT, stage and OS (p > 0.05). At same time, statistically significant difference was detected between high del(13q) (> 80%) and TTFT (p < 0.05). Conclusion The statistical analysis of our data regarding to the association between RB1 deletion and deletion type, TTFT, disease stage, and OS has not confirmed type II deletion or biallelic deletion cause poor prognosis. However, our data supports the deletion burden has a prognostic effect. More studies are needed to elucidate the cause of the clinical heterogeneity of CLL cases with del(13q).