Isolation and partial characterization of a new human glioblastoma cell line.

Although significant progresses were made in the field of molecular biology of malignant cerebral gliomas, the prognostic of these tumors continues to be reserved. One of the therapeutic failure reasons is the incomplete knowledge regarding the origin of these tumors and cells features, which in fact represent an obstacle in developing a cell and molecular therapy guided against malignant cells responsible for the tumor development and for the therapeutic resistance. Initiation and characterization of glioblastoma cell lines represents an essential step in order to obtain a better in vitro and in vivo experimental model for glioblastoma. We describe here a new glioblastoma line, named T11, which was successfully isolated in our laboratories starting with a tumor sample obtained intraoperative from a 58 years-old female patient. The histopathological evaluation showed a grad IV WHO glioma (glioblastoma). The sample was prepared by manual fragmentation, followed by enzymatic digestions using different concentration of trypsin. The cell line has been cultivated for more than 150 passages. The characterization of the glioblastoma line consisted in the evaluation of cells proliferation capacity (growth curve), morphological features, karyotyping and identification of specific markers. We found that T11 expressed specific markers for glial progenitors and astrocytes (glial fibrillary acidic protein-GFAP); oligodendrocites (A2B5; O4), and microglia (CD45, CD 11b). Cells were negative for neuronal lineage markers like beta3-tubulin and NCAM. In order to evaluate the differentiation grade of T11 cell line, the presence of stem cell markers (nestin, CD133) was explored. T11l cells expressed higher level of nestin and lower level of CD133 comparing with standard glioblastoma cell line U87. T11 cell line expressed VEGF and Bcl-2, but not EGFR and Mdrl and Bax. This new line has distinct and unique characteristics when compared with standard glioblastoma cell line (e.g., U87) and may become a new and useful in vitro model for glioblastoma.

Transcriptional silencing of ETS-1 efficiently suppresses angiogenesis of pancreatic cancer.

In this study, we addressed the hypothesis that transcriptional suppression of erythroblastosis virus E26 oncogene homolog 1 (ETS-1) is an efficient therapeutic approach to pancreatic adenocarcinoma by investigating the effect of ETS-1 suppression in human pancreatic cancer cells. We accomplished this by using an adenoviral vector encoding only the DNA-binding domain of wild-type ETS-1 (ETS-1 dominant negative, ETS-1-DN). ETS-1-DN decreases ETS-1-binding by competing for its binding to DNA. Adenoviral-mediated transfer of ETS-1-DN (adenoviral ETS-1-DN construct, AdETS-1-DN) into pancreatic tumor cell lines did not affect their proliferation rate in vitro but did significantly inhibit their in vivo growth in nude mice. Furthermore, to test the efficacy of ETS-1-DN in vivo, we injected the AdETS-1-DN into established human pancreatic adenocarcinomas grown in nude mice. This treatment significantly reduced tumor size as compared to saline injection, without any detectable side effects. Microvessel density in mouse xenografts displayed significantly lower values in tumors in which ETS-1 was downregulated. In addition, expression of the ETS-1-DN in the pancreatic cancer cells resulted in downregulation of urokinase-type plasminogen activator (u-PA) and metalloproteinase-1 (MMP-1) expression. Taken together, these data suggest that transcriptional inactivation of ETS-1 is able to significantly affect angiogenesis and growth of pancreatic cancer. This effect may be due in part to downregulation of MMP-1 and u-PA expression. Our results suggest that ETS-1-DN is a promising candidate for antiangiogenic gene therapy in pancreatic cancer.

Detection of human papillomavirus gene sequences in cell lines derived from laryngeal tumors.

The role of Human Papillomaviruses (HPV) in laryngeal carcinomas has been studied with conflicting results. To evaluate the etiologic relationship between HPV infection and epithelial malignancy of the larynx we studied five laryngeal carcinoma cell lines obtained from patients undergoing surgery for laryngeal tumors. The paraffin embedded biopsy samples of the original tumor and different passages of the new established cell lines were investigated by PCR with consensus primers specific for HPV DNA. The findings indicate that HPV infection is associated with some larynx carcinomas. The positive association has been enhanced when a method of enrichment of epithelial cells from fresh tumor samples was used. All tumor cells enriched smears were positive for HPV DNA not only by PCR but also by in situ hybridization (ISH). Investigated by PCR, different passages of larynx tumor cell lines maintained expression of HPV DNA. At subsequent passages ISH gives constantly no signals suggesting a minimal amount of viral harbored sequences. In one cell line propagated more than 60 population doublings, the chromosomal frequency distribution shifted from modal number 46 at the 5(th) passage to 63 at the 60(th) passage. The mechanisms by which persistent HPV infection maintains continuous cell proliferation were discussed.

Metabolic investigations in persistent depressive states in the elderly.

In a group of 100 elderly patients with persistent depressive states, a series of investigations were carried out: hematologic, lipid, protein, energy metabolism hydroelectrolytic and acid-base balance, blood rheologic properties, immunologic, reactivity and certain humoral and regulation mechanisms. The results were compared with those obtained in two control groups, identical in number, the former in the third age without depressive states and the latter of healthy adults. The results were evaluated statistically. The results demonstrate that in depressive elderly subjects changes of the various parameters studied occur in the same direction as those in the group of elderly subjects without depression, but are far more accentuated.