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941.
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943.
Human glioma cell culture: two FCS-free media could be recommended for clinical use in immunotherapy
Anne Clavreul Isabelle Jean Laurence Preisser Agnès Chassevent Anne Sapin Sophie Michalak Philippe Menei 《In vitro cellular & developmental biology. Animal》2009,45(9):500-511
Immunotherapy, particularly active vaccination, may be developed as an effective and safe treatment modality for malignant
gliomas, which continue to have a poor prognosis, despite advances in surgical techniques and adjuvant chemotherapy and radiotherapy.
Since no glioma-specific tumor-associated antigens (TAAs) have been discovered, autologous tumor cells or well-established
glioma cell lines could be used in future vaccination protocols to induce antitumour immunity against unknown TAAs. One obstacle
for clinical use of these tumour cell vaccines is related to foetal calf serum (FCS). Efforts are currently being directed
toward developing FCS-free media and serum-free alternatives to culture these cell vaccines. In this study, a medium containing
human serum and one serum-free medium (UltraCulture), supplemented or not with epidermal growth factor, were tested on morphology,
survival, DNA content and TAA expression of human glioma cell lines and glioma biopsy primary cultures. Their effects were
compared on FCS-containing medium. Results show that, whatever the medium used, no significant variations in morphology and
survival were observed. Furthermore, human serum-containing medium or UltraCulture preserved at early passage cultures the
cell population of interest present in the biopsies before culture. In addition, the expression profile of eight TAAs was
similar between these media. These data indicate that human serum-containing medium and UltraCulture serum-free medium could
be promising candidates to produce tumour-cell vaccines. 相似文献
944.
945.
M. Janssens 《生物化学与生物物理学报:生物膜》2009,1788(3):732-11
The barrier function of the skin is provided by the stratum corneum (SC), the outermost layer of the skin. Ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs) are present in SC and form highly ordered crystalline lipid lamellae. These lamellae are crucial for a proper skin barrier function. In the present study, Fourier transform infrared spectroscopy was used to examine the lipid organization of mixtures prepared from synthetic CERs with CHOL and FFAs. The conformational ordering and lateral packing of these mixtures showed great similarities to the lipid organization in SC and lipid mixtures prepared with native CERs. Therefore, mixtures with synthetic CERs serve as an excellent tool for studying the effect of molecular architecture of CER subclasses on the lipid phase behavior. In SC the number of OH-groups in the head groups of CER subclasses varies. Furthermore, acylCERs with a linoleic acid chemically bound to a long acyl chain are also identified. The present study revealed that CER head group architecture affects the lateral packing and conformational ordering of the CER:CHOL:FFA mixtures. Furthermore, while the majority of the lipids form a crystalline packing, the linoleate moiety of the acylCERs participates in a “pseudo fluid” phase. 相似文献
946.
Martin S Cosset EC Terrand J Maglott A Takeda K Dontenwill M 《Biochimica et biophysica acta》2009,1793(2):354-367
Caveolin-1 plays a checkpoint function in the regulation of processes often altered in cancer. Although increased expression of caveolin-1 seems to be the norm in the glioma family of malignancies, populations of caveolin-1 positive and negative cells coexist among glioblastoma specimens. As no data are available to date on the contribution of such cells to the phenotype of glioblastoma, we manipulated caveolin-1 in the glioblastoma cell line U87MG. We showed that caveolin-1 plays a critical role in the aggressiveness of glioblastoma. We identified integrins as the main set of genes affected by caveolin-1. We reported here that the phenotypic changes observed after caveolin-1 modulation were mediated by alpha(5)beta(1) integrins. As a consequence of the regulation of alpha(5)beta(1) levels by caveolin-1, the sensitivity of cells to the specific alpha(5)beta(1) integrin antagonist, SJ749, was affected. Mediator of caveolin-1 effects, alpha(5)beta(1) integrin, is also a marker for glioma aggressiveness and an efficient target for the treatment of glioma especially the ones exerting the highest aggressive phenotype. 相似文献
947.
Sophie Badie Chunyan Liao Maria Thanasoula Paul Barber Mark A. Hill Madalena Tarsounas 《The Journal of cell biology》2009,185(4):587-600
The RAD51 paralogues act in the homologous recombination (HR) pathway of DNA repair. Human RAD51C (hRAD51C) participates in branch migration and Holliday junction resolution and thus is important for processing HR intermediates late in the DNA repair process. Evidence for early involvement of RAD51 during DNA repair also exists, but its function in this context is not understood. In this study, we demonstrate that RAD51C accumulates at DNA damage sites concomitantly with the RAD51 recombinase and is retained after RAD51 disassembly, which is consistent with both an early and a late function for RAD51C. RAD51C recruitment depends on ataxia telangiectasia mutated, NBS1, and replication protein A, indicating it functions after DNA end resection but before RAD51 assembly. Furthermore, we find that RAD51C is required for activation of the checkpoint kinase CHK2 and cell cycle arrest in response to DNA damage. This suggests that hRAD51C contributes to the protection of genome integrity by transducing DNA damage signals in addition to engaging the HR machinery. 相似文献
948.
Sophie Marion de Procé Daniel L. Halligan Peter D. Keightley Brian Charlesworth 《Journal of molecular evolution》2009,69(6):601-611
Contrary to the classical view, a large amount of non-coding DNA seems to be selectively constrained in Drosophila and other
species. Here, using Drosophila miranda BAC sequences and the Drosophila pseudoobscura genome sequence, we aligned coding and non-coding sequences between D. pseudoobscura and D. miranda, and investigated their patterns of evolution. We found two patterns that have previously been observed in comparisons between
Drosophila melanogaster and its relatives. First, there is a negative correlation between intron divergence and intron length, suggesting that longer
non-coding sequences may contain more regulatory elements than shorter sequences. Our other main finding is a negative correlation
between the rate of non-synonymous substitutions (d
N) and codon usage bias (F
op), showing that fast-evolving genes have a lower codon usage bias, consistent with strong positive selection interfering with
weak selection for codon usage. 相似文献
949.
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