Establishment and characterization of a new human bladder cancer cell line showing features of squamous and glandular differentiation

Tumour-cell heterogeneity has been studied in a continuous cell line, UCRU-BL-17CL, established from a xenografted human primary bladder carcinoma. The cell line, grown in vitro for more than 30 generations, reflects the pathology of both the xenograft from which it was derived and the original human tumour. It comprises mainly adenocarcinoma cells which secrete mucin in vitro, as well as squamous and transitional carcinoma cells. Features of both adenocarcinomatous and squamous differentiation have been observed within the same cell. The line expresses ABH blood group isoantigens, binds to peanut lectin and reacts with monoclonal antibodies (MAbs) raised against keratin and against normal and malignant epithelial cells. It also reacts with MAbs against ras p21 proteins and the epidermal growth factor receptor (EGFR). It shows high levels of lactic acid dehydrogenase isozyme 5, consistent with a high-grade tumour, forms colonies in methylcellulose and is tumorigenic in nude mice. The karyotype (human) shows many marker chromosomes, consistent with expression of EGF receptors and ras p21 proteins, and an 11:13 translocation. DNA content, as studied by flow cytometry, reveals a shift from tetraploid to near triploid. This line may provide a useful model for studies of the histogenesis of bladder cancer and the relationship between transitional-cell carcinoma and the other histological subtypes of this disease.     

Monoclonal antibodies to detect human tumours: an experimental approach.

The use of monoclonal antibodies which can be raised to antigens of choice offers a selective and specific approach for the detection of tumours both in vivo and at a cellular level in biopsy specimens. We demonstrate that a monoclonal antibody raised to human teratoma will localise in a teratoma, growing as a xenograft in immune-suppressed mice.     

Differential affinity of anti-Pr-β-hCG-TT antibodies for hCG and hLH

Sera from four women immunized with the vaccine Pr-β-hCG-TT have been analysed for binding with hCG and hLH. Resolution of Scatchard plots showed the presence of more than one population of antibodies in these sera. In each case the Association Constants (Ka) of a population of antibodies for binding with hCG were distinctly higher than those for hLH. Results indicate the likely presence in β-hCG of determinants and/or conformations immunologically unique to hCG besides common regions.     

Complications of surgery and chemotherapy for testicular cancer

Testicular cancer is a malignancy for which an interdisciplinary approach offers the highest likelihood of cure. In many patients, both chemotherapy and surgery play a prominent role in their care. Although cure can be achieved in a majority of patients, the treatment can occasionally leave the patient with late sequelae. This article discusses the long-term toxicity of curative surgical or cytotoxic therapy for germ cell tumors.     

Quantified aneurysm shape and rupture risk

OBJECT: The authors investigated whether quantified shape or size indices could better discriminate between ruptured and unruptured aneurysms. METHODS: Several custom algorithms were created to quantifiy the size and shape indices of intracranial aneurysms by using three-dimensional computerized tomography angiography models of the brain vasculature. Data from 27 patients with ruptured or unruptured aneurysms were evaluated in a blinded fashion to determine whether aneurysm size or shape better discriminated between the ruptured and unruptured groups. Five size and eight shape indices were calculated for each aneurysm. Two-tailed independent Student t-tests (significance p < 0.05) were used to determine statistically significant differences between ruptured and unruptured aneurysm groups for all 13 indices. Receiver-operating characteristic-area under curve analyses were performed for all indices to quantify the predictability of each index and to identify optimal threshold values. None of the five size indices were significantly different between the ruptured and unruptured aneurysms. Five of the eight shape indices were significantly different between the two lesion groups, and two other shape indices showed a trend toward discriminating between ruptured and unruptured aneurysms, although these differences did not reach statistical significance. CONCLUSIONS: Quantified shape is more effective than size in discriminating between ruptured and unruptured aneurysms. Further investigation will determine whether quantified aneurysm shape will prove to be a reliable predictor of aneurysm rupture.     

Tyrosine phosphatase regulation of MuSK-dependent acetylcholine receptor clustering

During vertebrate neuromuscular junction (NMJ) development, nerve-secreted agrin induces acetylcholine receptor (AChR) clustering in muscle by activating the muscle-specific tyrosine kinase MuSK. Recently, it has been recognized that MuSK activation-dependent AChR clustering occurs in embryonic muscle even in the absence of agrin, but how this process is regulated is poorly understood. We report that inhibition of tyrosine phosphatases in cultured C2 mouse myotubes using pervanadate enhanced MuSK auto-activation and agrin-independent AChR clustering. Moreover, phosphatase inhibition also enlarged the AChR clusters induced by agrin in these cells. Conversely, in situ activation of MuSK in cultured Xenopus embryonic muscle cells, either focally by anti-MuSK antibody-coated beads or globally by agrin, stimulated downstream tyrosine phosphatases, which could be blocked by pervanadate treatment. Immunoscreening identified Shp2 as a major tyrosine phosphatase in C2 myotubes and down-regulation of its expression by RNA interference alleviated tyrosine phosphatase suppression of MuSK activation. Significantly, depletion of Shp2 increased both agrin-independent and agrin-dependent AChR clustering in myotubes. Our results suggest that muscle tyrosine phosphatases tightly regulate MuSK activation and signaling and support a novel role of Shp2 in MuSK-dependent AChR clustering.     

Effects of AAV-2-mediated aspartoacylase gene transfer in the tremor rat model of Canavan disease

The tremor rat is a spontaneous epilepsy model with a seizure phenotype caused by a deletion in the aspartoacylase (ASPA) gene. The absence of ASPA expression in these animals results in undetectable levels of enzyme activity and the accumulation of the substrate N-acetyl-aspartate (NAA) in brain, leading to generalized myelin vacuolation and severe motor and cognitive impairment. In support of human gene therapy for CD, recombinant adeno-associated viral vector (AAV-2) expressing ASPA was stereotactically delivered to the tremor rat brain and effects on the mutant phenotype were measured. AAV-ASPA gene transfer resulted in elevated aspartoacylase bioactivity compared to untreated mutant animals and elicited a significant decrease in the pathologically elevated whole-brain NAA levels. Assessment of motor function via quantitative rotorod testing demonstrated that rats injected with AAV-ASPA significantly improved on tests of balance and coordinated locomotion compared to animals receiving control vectors. This study provides evidence that AAV-2-mediated aspartoacylase gene transfer to the brain improves biochemical and behavioral deficits in tremor rat mutants (tm/tm) and supports the rationale of human gene transfer for Canavan disease.     

Prevalence of diabetes mellitus and dyslipidemia among antiretroviral naive patients co-infected with hepatitis C virus (HCV) and HIV-1 compared to patients without co-infection

OBJECTIVE: An increased prevalence of type 2 diabetes mellitus (DM) has been associated with HCV in the non-HIV infected populations. To describe a similar association among HIV subjects, and explore the biological mechanisms. METHODS: In a cross-sectional analysis, we compared the prevalence of DM (using American Diabetes Association criteria) and insulin resistance (HOMA IR) and dyslipidemia among ARV naive patients with HIV and HIV/HCV infected patients enrolled in CPCRA FIRST (058) and the Metabolic Substudy (061). RESULTS: Among 1389 enrolled in the FIRST study and had HCV serology, the prevalence of diabetes was higher (5.9%) among HCV/HIV as compared to 3.3% among those with HIV alone (p=0.04). Among 417 enrolled in the metabolic substudy, 88 (21%) had HIV/HCV co-infection. As in the main study, the prevalence of DM was higher in HIV/HCV group (9 vs. 3%, p=0.03). The HIV/HCV infected were significantly older (43 vs. 37 years), non-white (83 vs. 70%), with a history of IDU (55 vs. 3%), had higher AST (61 vs. 39 U/l), ALT (55 vs. 43 U/l,) and lower cholesterol levels (3.97 vs. 4.25 mmol/l). By multivariate analysis among subjects <50 years, association between HCV and diabetes remained significant after adjusting for BMI, family history of diabetes (OR=3.7, 95% CI: 1.3-11.1, p=0.02). The insulin resistance (HOMA IR) was not different between the two groups, however, the prevalence of dyslipidemia was lower among HCV co-infected subjects. CONCLUSIONS: Subjects with HIV/HCV co-infection have a higher prevalence of diabetes and thus may need to be screened for it prior to initiation of anti-retroviral therapy, particularly if it is a PI based regimen.