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Glycosaminoglycans (GAGs), normal components of the extracellular matrix (ECM), and the glycosidases, that degrade them, play a key role in the bone remodelling process. The effects of interleukin-1 alpha (IL-1 alpha) on GAG metabolism in normal and otosclerotic human bone cells as well as its capacity to modulate IL-1 alpha, IL-1 beta and IL-6 secretion in both populations was analyzed. The amount of radiolabeled GAGs was lower in otosclerotic than in normal bone cells. IL-1 alpha reduced newly synthesized cellular and extracellular GAGs in normal cells, but only those of the cellular compartment in otosclerotic bone cells. It depressed heparan sulphate (HS) more in normal cells and chondroitin sulphate (CS) more in otosclerotic bone cells. The HA/total sulphated GAG ratio was shifted in favour of the latter in otosclerotic cells, whereas the opposite effect was seen after IL-1 alpha treatment. There was little difference in the beta-D-glucuronidase levels of the normal and pathological cells, while beta-N-acetyl-D-glucosaminidase was significantly increased in otosclerotic bone cells. As the activity of neither enzyme was modified by treatment with IL-1 alpha, the cytokine seems to exert its influences on GAG synthesis rather than on the degradation process. IL-1 alpha, IL-1 beta and IL-6 secretion was markedly higher in otosclerotic cells. IL-1 alpha modulated the secretion of each interleukin differently, thus resulting in a cytokine cascade that may act in autocrine/paracrine manner on target cells. The authors suggest that changes in the cytokine network may have a specific, yet still unknown, role during normal and pathological osteogenesis.

The expression of fragile sites induced by aphidicolin (APC) was evaluated on metaphase chromosomes obtained from the peripheral blood lymphocytes of 26 women with breast cancer and 15 sex- and age-metched normal controls. Both the proportion of damaged cells (P

We describe a 4-year-old female child with severe global mental retardation, myoclonic epilepsy, proximal hypotonia and dysmorphisms, whose prenatal diagnosis following amniocentesis revealed a constitutional female karyotype carrying a t(1;15)(q10;p11) familial reciprocal translocation. Post-natal high-resolution karyotype, Fluorescence in situ hybridization (FISH) screening for subtelomeric rearrangements, VNTR search for UPD15 in the blood and fibroblast, and WCP1 and 15 in the mother, failed to provide an explanation for the complex clinical phenotype of the proband. Since the pachytene configuration of the translocated chromosomes defines a high probability of 3:1 segregation, an extensive workup was undertaken to look for a possibly cryptic mosaicism. Four percent of the cells with trisomy 15 was found in the peripheral blood lymphocytes examined by classical cytogenetic technique and interphase FISH analysis. The clinical features associated with cryptic trisomy 15 mosaicism and the problems concerning prenatal diagnosis and genetic counselling for carriers of translocations at high risk of 3:1 segregation are discussed. Copyright © 2006 John Wiley & Sons, Ltd.

Fifty-two kariotypic abnormalities additional to Philadelphia chromosome (Ph’) were documented at the time of diagnosis or during the course of the disease in 114 CML patients. Five were evaluated only once at the time of diagnosis, while 109 were repeatedly studied overtime during a median period of 138 (1–275)months. A clonal evolution was already present at diagnosis (early clonal evolution) in 12, while in 23 patients, it was documented in the course of the disease (late clonal evolution). Simultaneous appearence of multiple chromosome abnormalities (4/12 and 4/23) and a tendency to acquire further alterations (5/12 and 2/23, respectively) were associate with both early and late secondary clones. Partial or complete chromosome losses (-1, -6, 6q-, 7p-, 11q-, 12p-, -14, -16, -17,-18, -21) other than -Y (11 events), + 8 (9) and loss of Y chromosome (8) were the most commonly cytogenetic abnormalities, irrespective of the time of their occurrence. Translocations other than Ph’ (5 events), complex Ph’ translocations (5), duplication of Ph’ (5), single iso(Ph’) (4), duplication of iso(Ph’) (1) or iso17q (2) were found with a decreasing frequency. The type of kariotypic alteration varied with the time of onset. In fact, partial or complete chromosome monosomies and duplication of iso(Ph’) never represented early, but only late events. Duplication of Ph’ was a late (4/5) rather than an early event (1/5). Similarly, the presence of the iso(Ph’) was documented either in early or late clonal evolution in 1 and 3 instances respectively. Furthermore, +8 developed several months after diagnosis in all, but 2 cases. Complex Ph’ translocations or loss of Y chromosome do not correlate with any specific phase of the leukemic course. Cytogenetic abnormalities neither correlated with Sokal risk nor with the type of break-points (b3a2,b2a2) documented at diagnosis. However all 3 clones bearing p230 chimeric protein showed early cytogenetic evolution. Secondary clones seem to have different impact on disease history. The occurrence of partial or complete deletions, the iso17q and the late, but not early, loss of Y chromosome were all predictive of a rapid disease progression. Early secondary clones with additional translocations had no effect on the chronic behaviour of the disease, while such clones were associated with a rapid progression (2/3) to blastic phase when they occurred during the course of disease. The presence of +8 as the sole cytogenetic abnormality and complex translocations, irrespective of the time of their onset, did not correlate with leukemia evolution. Finally,simple Ph’ duplication of or single and double iso(Ph’), when not associated with other cytogenetic abnormalities, did not correlate with an aggressive course, even if it can be assumed that these cytogenetic events are responsible for an increased concentration of the p210 oncoprotein. In conclusion, regardless of whether bcr/abl has a direct or an indirect role in promoting genomic instability, in our cohort of CML patients additional non random chromosomal abnormalities frequently characterize both early and late phase of the disease and some of them may represent crucial steps in development and progression of leukemia.

The finger motif is a tandemly repeated DNA-binding domain recently identified in the primary structure of several eukaryotic transcriptional regulatory proteins. It has been proposed that some members of the finger-gene family are implicated in both normal cell proliferation and differentiation. We isolated several human finger genes by means of hybridization with a finger motif-containing DNA probe. One of these finger genes, HF.10, is expressed at low levels in a variety of human tissues and is down-regulated during the in vitro terminal differentiation of human leukemic myeloid cell lines. By in situ hybridization experiments and analysis of interspecific somatic cell hybrids we mapped the HF.10 gene to 3p21-22, a chromosome region frequently involved in karyotypic rearrangements associated with lung and renal cancer.

Normal and otosclerotic bone cells were cultured in vitro in serum-free medium to evaluate single glycosaminoglycan (GAG) class synthesis and secretion. Moreover, the degradative process was studied by inhibiting the lysosomal functions through the addition of ammonium chloride to the cultures, an ammine known to inhibit lysosomal degradation by neutralizing organelle activity. Otosclerotic bone cells accumulated a lower amount of GAG both in the cellular and extracellular pool compared to normal ones. The decrease was markedly higher for secreted GAG. Moreover a different pattern of single GAG class distribution was observed in the two cell types considered. In the medium of otosclerotic cells a percentage increase of hyaluronic acid (HA) and dermatan sulphate (DS) and a percentage decrease of heparan sulfate (HS) and chondroitin sulfate (CS) were observed compared to normal bone cells. Ammonium chloride had a lower effect on pathologic than on normal cells, indicating a decrease in the degradative process in otosclerotic bone cells. These results were also confirmed by the experiments on GAG uptake and degradation and by the dosage of enzymatic activity of two exoglycosidases. Since extracellular GAG composition influences bone deposition and mineralization, these data support the hypothesis that otosclerosis is the result of an error in the connective tissue matrix structure.