Bogdan Kałużewski

Demonstration of Two Different Regions of Lateral Asymmetry in Human Y Chromosomes

SummaryTwo differently stained regions of lateral asymmetry were observed in the long arm of the human Y chromosome, following FPG staining. The first asymmetry was confined to band q12 of the long arm. The second asymmetrically stained region was located at the junction between bands q11 and q12. In the non-fluorescent Y chromosomes only one region of lateral asymmetry was found at the end of the long arm and its staining properties were similar to the region situated at the junction between q11 and q12 bands in the fluorescent Ys. The two morphologically distinguishable regions of lateral asymmetry are presumed to indicate sites containing different satellite DNAs in the human Y chromosome.

Regular trisomy 21 not accompanied by increased copper‐zinc superoxide dismutase (SOD1) activity

The Cu‐Zn superoxide dismutase (SOD1) activity was estimated in red blood cells in children with regular trisomy 21. We report patients displaying typical Down syndrome clinical features and with SOD1 activity in the normal range.

Copper/zinc superoxide dismutase (SOD‐1) activity in regular trisomy 21, trisomy 21 by translocation and mosaic trisomy 21

Cu/Zn superoxide dismutase (SOD‐1) (E.C.1.15.1.1.) activity was estimated in children with regular trisomy 21‐Down syndrome as well as in cases of translocation and mosaic trisomy 21, as identified by the GTG, CBG and RHG banding techniques. SOD‐1 activity was found to be increased in all examined cases except trisomy 21 mosaicism. These findings provide further proof of the gene dosage theory and additional biochemical evidence for the triplicate existence of the SOD‐1 gene localized on chromosome 21

A novel mutation (c. 341A>G) in the SRY gene in a 46,XY female patient with gonadal dysgenesis.

SRY (sex-determining region Y) gene, MIM 480000, NM_005634) is crucial for sex differentiation which encodes the protein responsible for initiating testis differentiation. SRY mutations are associated with the presence of XY gonadal dysgenesis symptoms. We studied a 46,XY female patient with primary amenorrhoea and negative family history. The clinical, endocrine, histopathologic and cytogenetic data are consistent with gonadal dysgenesis. Using a molecular analysis, a novel (c.341A>G, p. N65D) missense mutation within the HMGbox of SRY gene was detected. Escherichia coli expression of SRY study showed reduced expression of the mutated protein and gel retardation assay method revealed lowered DNA-binding ability in N65D variant of SRY. The novel mutation detected in the SRY gene may be an aetiopathogenic factor in clinically defined 46,XY complete gonadal dysgenesis (CGD). Because of an increased risk of gonadoblastoma, proper early diagnosis and treatment prevent development of malignancies.

Molecular analysis of Y chromosome long arm structural instability in patients with gonadal dysfunction

We have performed cytogenetic and molecular analyses of 45,X mosaics involving structurally abnormal Y chromosomes. Karyotypes were performed by standard cytogenetic methods and, in some cases, by fluorescence in situ hybridization, to distinguish monocentric and dicentric chromosomes. In addition, the deletions of Yq have been mapped using Southern blotting and polymerase chain reaction analysis. This paper provides additional information on the analysis of Y chromosome aberrations, and suggests that the stability of the Y chromosome in these instances is related to the site of the break point on Yq.

EORTC risk tables - their usefulness in the assessment of recurrence and progression risk in non-muscle-invasive bladder cancer in Polish patients.

Introduction The assessment of risk of recurrence and progression of bladder cancer (BC) is still rather difficult. We decided to check the rates of the changes mentioned above in the group of the Polish patients after a year–long observation and next to compare them with the results calculated in the European Organisation of Research and Treatment of Cancer (EORTC) risk tables. Methods The tested group consisted of 91 patients who underwent transurethral resection of bladder tumour (TURBT). When being diagnosed, 60 cases were in the pTa clinical stage, whereas 30 cases were in T1. The coexisting carcinoma in situ (CIS) was observed in four cases. On the basis of the scores obtained from the EORTC tables, the patients were divided into the groups of low, intermediate or high risk of disease recurrence and progression. Results Recurrence was noticed in 23 patients (25%), while progression was observed in 11 patients (12.1%). The rate of the observed recurrences proved to be lower than it had been predicted in all the groups, except for one of the intermediate–risk group (score 1– 4). Moreover, the rate of the progressions predicted according to the EORTC risk tables was higher in all the risk groups. Conclusions It can be noticed that the rate of real recurrences is lower than expected, whereas the rate of the observed progressions is overestimated. Partly, it could be the result of using a relatively small group of patients for observation and applying a different method of treatment.

A case of renal lymphangioma with a karyotype 45,X,−X,i dic(7q)

Cytogenetic analysis of a polycystic unilateral renal lymphangioma was performed by short-term culture and banding methods. The tumors cells showed an isochromosome of the long arm of chromosome #7 and monosomy of X chromosome, whereas the peripheral lymphocytes stimulated with phytohemagglutinin showed a normal female karyotype, 46,XX. These karyotypic anomalies suggest that lymphangioma, although clinically benign, may have malignant potential.

Application of multiplex FISH, CGH and MSSCP techniques for cytogenetic and molecular analysis of transitional cell carcinoma (TCC) cells in voided urine specimens

Multiplex FISH (UroVysion), Comparative Genomic Hybridization (CGH), and Multitemperature Single-Strand Conformation Polymorphism (MSSCP) were applied for non-invasive diagnosis and prognosis of bladder cancer. The Uro Vysion test was positive in 80% of patients with pT1 and in 100% of patients with either pT2 or pT3 tumours. Tumours with pT3T4 stages were characterized by high numbers of chromosomal imbalances, detected by CGH. The mutation of the p53 gene was detected in 16% of patients, but only in those with pT2 or pT3 tumours.

The risk of neoplasm associated with dysgenetic testes in prepubertal and pubertal/adult patients

INTRODUCTION In patients with Y-chromosome in the karyotype, partial gonadal dysgenesis and disorders of male reproductive sex organs development are usually resected in childhood because of the high risk of germ cell tumours (GCT). In patients with Y-chromosome, complete gonadal dysgenesis and female genitalia gonadectomy is performed markedly later. However, due to the relatively low number of adult patients with preserved dysgenetic gonads, the true risk of neoplasm is unknown. The aim of the study was to evaluate the prevalence of neoplasia in dysgenetic gonads of children and adults with Y-chromosome in a retrospective study. MATERIAL AND METHODS A review of medical documentation of 94 patients with disorders of sex development (DSD), Y-chromosome and gonadal dysgenesis (GD), aged 1.2-32 years (47 prepubertal, 1.2-10 years; 47 pubertal/adult, 13-32 years), was conducted. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone were determined. Bilateral gonadectomy was performed in 73.4% of patients, and unilateral gonadectomy with biopsy of the contralateral gonad in 26.4%. All gonadal tissues were subjected to immunohistochemical evaluation with antibodies against PLAP and OCT3/4 (markers of malignant germ cells, but also foetal multipotent germ cells), while gonads of prepubertal patients were examined by c-KIT, as well. RESULTS Streak gonads were identified on both sides (complete GD) in 30.8%, a streak gonad on one side and an underdeveloped testis on the other (asymmetric GD) in 38.3%, and underdeveloped testicular structure on both sides (partial GD) in 30.8% of cases. Germ cell neoplasia was found in 53.2% of patients (51.1% in children, 55.3% in pubertal/adults). Invasive GCT were identified in 11.7% of cases, of which 90.9% were in pubertal/adult patients. Other neoplastic lesions included gonadoblastoma (16% prevalence) and testicular carcinoma in situ (25.5%). In younger patients FSH serum levels were increased in 81% of cases (mean 2.82 ± 2.18 IU/L), while LH in 58% (mean 1.82 ± 1.69 IU/L). Hypergonadotropic hypogonadism was diagnosed in most of the pubertal/ /adult patients (mean FSH 54.2 ± 23.3 IU/L, mean LH 21.7 ± 12.1 IU/L, mean testosterone 5.5 ± 4.5 nmol/L). CONCLUSIONS Dysgenetic gonads in patients with Y chromosome have a high risk of germ cell neoplasia (ca. 50%). If they are preserved until puberty/early adulthood, they may develop overt, invasive GCT. The gonads also have poor hormonal activity (hypergonadotropic hypogonadism) in most of the pubertal/adult patients. Each of these cases must be considered individually and a decision to remove the gonad or not should be based on the comprehensive analysis of the phenotype by a multidisciplinary team of specialists in consultation with the patient and the parents. If dysgenetic gonads are not resected in childhood, these patients need careful ongoing follow-up examination, including biopsy and histopathological evaluation.

Molecular subtyping of bladder cancer using Kohonen self-organizing maps.

Kohonen self‐organizing maps (SOMs) are unsupervised Artificial Neural Networks (ANNs) that are good for low‐density data visualization. They easily deal with complex and nonlinear relationships between variables. We evaluated molecular events that characterize high‐ and low‐grade BC pathways in the tumors from 104 patients. We compared the ability of statistical clustering with a SOM to stratify tumors according to the risk of progression to more advanced disease. In univariable analysis, tumor stage (log rank P = 0.006) and grade (P < 0.001), HPV DNA (P < 0.004), Chromosome 9 loss (P = 0.04) and the A148T polymorphism (rs 3731249) in CDKN2A (P = 0.02) were associated with progression. Multivariable analysis of these parameters identified that tumor grade (Cox regression, P = 0.001, OR.2.9 (95% CI 1.6–5.2)) and the presence of HPV DNA (P = 0.017, OR 3.8 (95% CI 1.3–11.4)) were the only independent predictors of progression. Unsupervised hierarchical clustering grouped the tumors into discreet branches but did not stratify according to progression free survival (log rank P = 0.39). These genetic variables were presented to SOM input neurons. SOMs are suitable for complex data integration, allow easy visualization of outcomes, and may stratify BC progression more robustly than hierarchical clustering.