Comparative genomic hybridization of 49 primary retinoblastoma tumors identifies chromosomal regions associated with histopathology,progression, and patient outcome

Forty-nine primary retinoblastoma (Rb) tumors were analyzed by the use of comparative genomic hybridization (CGH), and clinical/histological correlations were performed. Adverse histological factors were present in 13 patients. Chromosomal imbalance was a frequent phenomenon, seen in 96% of the tumors. Gain of 6p represented the most frequent event (69% of the tumors), whereas +1q was observed in 57%, confirming that these abnormalities are key secondary events in retinoblastoma tumor progression. Loss of 13q and 16 was significantly associated with tumors displaying adverse histo-prognostic factors, whereas -16q was significantly associated with tumors without adverse features. In three patients who developed an extra-ocular relapse, the tumors showed -13q and 2/3 had -5q, suggesting that these abnormalities may be associated with metastasis. Children >or= 36 months of age at enucleation tended to have more CGH abnormalities per tumor than children < 12 months (median numbers 11 vs. 3). In addition, +1q, +13q, -16, and -16q were more frequent in children with an older age at enucleation. Identical CGH changes were found in both tumors from one patient with bilateral tumors, suggesting a common origin. It is possible that tumors displaying loss of 13q and 5q indicate those patients who may suffer an adverse outcome and who would require alternative or more intensive therapy. CGH analysis on larger cohorts and in prospective clinical trials will be invaluable in determining whether a genetic classification of retinoblastoma represents a reliable measure of prognosis.     

Mouse Sperm Rosette: Assembling During Epididymal Transit,in vitro Disassemble,and Oligosaccharide Participation in the Linkage Material

In many mammals, sperm associations had been observed, but not in the mouse. In this work, mouse sperm rosettes are morphologically described inside the epididymis and during its dissolution in a culture medium. Also characterized are the saccharides present in the linking material. Sperm association and other epididymal actions are supported by sperm during epididymal transit and are verified at the caudal region, suggesting a relation between epididymal transit and sperm maturation. In drops of epididymal content obtained from distal (cauda), but not from proximal (caput and corpus) regions; dissolved in culture medium, rosettes appear to be 10 to 15 motile sperm joined by their heads. After 3 min, sperm progressively detach, disassembling the rosette. These structures are studied by several techniques, including optic, electronic (scanning electron microscopy and transmission electron microscopy), and video microscopy. At the ultrastructural level, a dense network of electron‐dense material was observed between sperm heads, joining them. Based on previous works in rat, several lectins were used to characterize the type of saccharides present in this linking material. To avoid the contact between sperm and epididymal fluid from distal region—that probably exerts an influence on sperm association—a ligature was placed between caput and corpus. This epididymal content isolated from caput did not display any rosettes after 28 days. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.     

Tumor-induced tolerance and immune suppression by myeloid derived suppressor cells

Summary: Emerging evidence indicates that the Achilles' heel of cancer immunotherapies is often the complex interplay of tumor-derived factors and deviant host properties, which involve a wide range of immune elements in the lymphoid and myeloid compartments. Regulatory lymphocytes, tumor-conditioned myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages, and dysfunctional and immature dendritic cells take part in a complex immunoregulatory network. Despite the fact that some mechanisms governing tumor-induced immune tolerance and suppression are starting to be better understood and their complexity dissected, little is known about the diachronic picture of immune tolerance. Based on observations of MDSCs, we present a time-structured and topologically consistent idea of tumor-dependent tolerance progression in tumor-bearing hosts.     

Plasminogen activator system modulates invasivecapacity and proliferation in prostatic tumor cells

The malignant phenotype of prostatic tumor cells correlates with the expression of both uPA and itscell-membrane receptor (uPAR); however, there is little information concerning the role of cell-bound uPAin matrix degradation and invasion. Our results suggest that cell-associated uPA plays a key role in regulat-ingthe amount of plasmin present at the surface of prostatic carcinoma (PRCA) cells and show that differ-entialproduction of uPA corresponds with the capacity to bind and activate plasminogen. In addition, weprovide direct evidence that both uPA secretion and the presence of uPA-uPAR complexes characterize theinvasive phenotype of PRCA cells and suggest the existence of several pathways by which tumor cells acquireplasmin activity. LNCaP cells (which do not produce uPA but express uPAR) may activate plasmin throughexogenous uPA. In vivo, the source of uPA may be infiltrating macrophages and/or fibroblasts as observedin several other systems. PAI-1 accumulation in the conditioned medium (CM) limits plasmin action to thepericellular microenvironment. Our results indicate that MMP-9 and MMP-2 are also activated by plasmingenerated by cell-bound but not by soluble, extracellular uPA. Plasmin activation and triggering of the pro-teolyticcascade involved in Matrigel invasion is blocked by antibodies against uPA (especially by anti- A-chainof uPA which interacts with uPAR) and by PA inhibitors such as p-aminobenzamidine which mayregulate levels of cell-bound uPA. uPA may also regulate growth in PRCA cells. Indeed, antibodies againstuPA A-chain (and also p-aminobenzamidine treatment) interfere with the ATF domain and inhibit cell growthin uPA-producing PC3 and DU145 prostate cancer cell lines, whereas exogenous uPA (HMW-uPA with ATF)induces growth of LNCaP prostate tumor cell line. These data support the hypothesis that in prostatic can-cerpatients at risk of progression, uPA/plasmin blockade may be of therapeutic value by blocking both growthof the primary tumor and dissemination of metastatic cells. ©Kluwer Academic Publishers     

A comprehensive in vitro characterization of pancreatic ductal carcinoma cell line biological behavior and its correlation with the structural and genetic profile

There are a large number of stable pancreatic ductal carcinoma cell lines (PDCL) that are used by researchers worldwide. Detailed data about their differentiation status and genetic alterations are present in the literature, but a systematic correlation with cell biological behavior is often lacking. PDCL (n=12) were clustered by source of tumor cell (ascites, primary tumor, metastasis), and the data of functional cell biology were correlated with the reported structural and genetic profiles. Major histocompatibility complex expression, chemosensitivity and aneuploidia appeared to be related to the source of PDCL, and proliferative capacity appeared to be related to the grade of differentiation. No correlation between genetic/structural features of PDCL and biological behavior was found. All the cell lines appeared generally insensitive to in vitro treatment with 5-fluorouracil and showed variable degrees of susceptibility to gemcitabine, raltitrexed and oxaliplatin. All the PDCL showed resistance to Fas-mediated apoptosis but were significantly sensitive to the pro-apoptotic effect of inflammatory cytokines [interleukin (IL)-1, tumor necrosis factor (TNF) and interferon ]. PDCL were characterized for the secretion of several factors relevant to the tumor-immune cross talk. Vascular endothelial growth factor, CCL2, CCL5 and transforming growth factor were the factors most frequently released; less frequent was the secretion of CXCL8, CCL22, IL-6 and sporadically CXCL12, IL-10 and hepatocyte growth factor. The cytokines IL-1 and TNF were always undetectable. In conclusion, a clear correlation between structural/genetic features and function could not be detected, suggesting the weakness of a morphological classification for the in vitro studies of pancreatic cancer.     

Association between presenilin-1 -48C/T polymorphism and Down's syndrome

Individuals with Down's syndrome (DS), i.e., trisomy 21, over 40 years of age, are likely to develop neuropathological changes characteristic of Alzheimer's disease (AD). The involvement of chromosome 21 both in DS and AD suggests a shared genetic susceptibility to these disorders, but genetic determinants are still undefined. The -48C/T polymorphism in the PSEN1 promoter is a possible candidate, since it has recently been associated with an increased risk of early onset AD. Based on the assumption that the excess of dementia in DS might be a consequence of a different distribution of the -48C/T polymorphism, we investigated the association between DS and this polymorphism in patients with trisomy 21 and controls. Overall, 260 DS patients and 197 controls were recruited at the Department of Neurosciences, Tor Vergata University of Rome. Cases and controls had similar age and gender distribution. High molecular weight DNA was extracted from whole blood samples collected in EDTANa(2) and -48C/T genotypes were determined. Genotype and allele frequencies were compared between cases and controls. Cases were less likely than controls to have the CC genotype ( P = 0.05). A significant difference for allele distribution between DS cases and controls was found, with DS showing a lower frequency of the allele C compared with the control population (OR: 0.57; 95% CI: 0.35-0.91; P = 0.01). No significant interaction of PSEN1 with age, gender, ApoE and -850 TNF-alpha polymorphisms was found. The association found suggests that the -48C/T polymorphism in the PSN1 gene promoter, which is involved in the modulation of amyloid beta load in human AD, is associated with DS. However, the biological role of this polymorphism in DS-related dementia remains unclear and merits further investigation.     

Congenital infection with human herpesvirus 6 variant B associated with neonatal seizures and poor neurological outcome

Human herpesvirus 6 (HHV 6) has neurotropic and neuroinvasive properties. The virus has been found in the cerebrospinal fluid of many children with aseptic meningoencephalitis. Intrauterine transmission has been documented by HHV 6 DNA detection in cord blood specimens of apparently healthy newborns and in fetuses following spontaneous abortions. A patient is described with early neonatal afebrile seizures resulting from a congenital HHV 6 variant B infection disclosed by repeated detection of viral genome by polymerase chain reaction (PCR) in cerebrospinal fluid in the first days of life. At follow-up, magnetic resonance imaging (MRI) studies disclosed hyperintensities in the periventricular white matter and basal ganglia, associated with cerebral atrophy. Further follow-up at 18 months revealed poor neurological outcome with mild neurodevelopmental retardation, strabismus and hypertonia of legs. This report provides evidence of neurological involvement after HHV 6 vertical transmission, and the association with neurological sequelae.     

Clinical and molecular study in congenital muscular dystrophy with partial laminin alpha 2 (LAMA2) deficiency

Complete laminin alpha2 (LAMA2) deficiency causes approximately half of congenital muscular dystrophy (CMD) cases. Many loss-of-function mutations have been reported in these severe, neonatal-onset patients, but only single missense mutations have been found in milder CMD with partial laminin alpha2 deficiency. Here, we studied nine patients diagnosed with CMD who showed abnormal white-matter signal at brain MRI and partial deficiency of laminin alpha2 on immunofluorescence of muscle biopsy. We screened the entire 9.5 kb laminin alpha2 mRNA from patient muscle biopsy by direct capillary automated sequencing, single strand conformational polymorphism (SSCP), or denaturing high performance liquid chromatography (DHPLC) of overlapping RT-PCR products followed by direct sequencing of heteroduplexes. We identified laminin alpha2 sequence changes in six of nine CMD patients. Each of the gene changes identified, except one, was novel, including three missense changes and two splice-site mutations. The finding of partial laminin alpha2 deficiency by immunostaining is not specific for laminin alpha2 gene mutation carriers, with only two patients (22%) showing clear causative mutations, and an additional three patients (33%) showing possible mutations. The clinical presentation and disease progression was homogeneous in the laminin alpha2-mutation positive and negative CMD patients.     

Bleeding patterns in recent postmenopausal outpatients with uterine myomas: comparison between two regimens of HRT

Objectives: To evaluate and to compare the bleeding patterns obtained with two regimens of hormone replacement therapy given to early postmenopausal women with asymptomatic uterine leiomyomas. Methods: In this randomised prospective 1-year study 50 early postmenopausal women with one to four asymptomatic uterine leiomyomas were enrolled into two study-groups to take two regimens of hormone replacement therapy for 12 28-day cycles: (A) Tibolone, 2.5 mg/day; (B) conjugated equine estrogens (CEE), 0.625 mg/day plus medroxyprogesterone acetate (MPA), 5 mg/day. The bleeding patterns and the changes in uterine volume of the 47 outpatients who completed the study were evaluated and compared. Results: Amenorrhea incidence was higher in group A (75.0% of the cycles) than in group B (65.6% of the cycles), while irregular bleeding and irregular spotting incidences were higher in group B (29.7 and 4.7% of the cycles, respectively) compared to group A (22.6 and 2.4% of the cycles, respectively). The mean bleeding and spotting lengths were not statistically different between patients in group A and those in group B. Finally, at the end of the study period transvaginal ultrasonography showed no significant change in leiomyoma size. Conclusions: The results demonstrate that, in early postmenopausal patients with asymptomatic uterine leiomyomas, Tibolone treatment seems to be preferable compared to CEE–MPA continuous combined treatment in relation to the lesser occurrence of irregular bleeding. Furthermore, neither Tibolone nor CEE–MPA therapy, at the doses used here, promote fibroid growth.