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Cell Line Isolated (cell + line_isolated)
Selected AbstractsMethylseleninic acid enhances the effect of etoposide to inhibit prostate cancer growth in vivoINTERNATIONAL JOURNAL OF CANCER, Issue 6 2007Oscar Gonzalez-Moreno Abstract New therapeutic agents are needed for the treatment of androgen-independent prostate cancer (PrCa). We have investigated the effect of methylseleninic acid (MSA) on tumor stage-specific prostate cells derived from the C3 (1)/Tag model for PrCa: Pr111, a slow-growing and nontumorigenic cell line isolated from a prostate intraepithelial neoplasia lesion; Pr14, a tumorigenic line derived from a primary tumor; and Pr14C1, a sub-clone of Pr14 explanted from a lung metastasis. We demonstrate that MSA strongly inhibits cell growth and induces apoptosis in C3 (1)/Tag tumor cells, in a dose-dependent manner. A decrease in phosphorylated ERK1/2 and AKT was also found in tumor cells, but not in Pr111. Microarray analysis using affymetrix showed that the number of genes with an altered expression in tumor cells is significantly higher (p < 0.01) than in nontumoral cells. Pathways analyses revealed a decrease in the expression of genes involved in metabolism (Fabp5, Cyba), signal transduction (ERK, AKT), angiogenesis (neuropilin-1, Flt-4) and transcription (cAMP response element-binding protein) in tumor cells. The expression of neuropilin-1, a protein involved in VEGF signaling and tumor angiogenesis, was 97-fold repressed in Pr14 cells treated with MSA. Combination treatments using low doses of etoposide or taxotere (docetaxel), plus low doses of MSA revealed a strong enhancement of cell growth inhibition and apoptosis in tumor cells. Our in vivo studies using Pr14 cells xenografted into nude mice demonstrated that MSA significantly enhances the chemotherapeutical effect of etoposide, resulting in 78.3% tumor growth inhibition. These results suggest that MSA could be used against PrCa to enhance the effect of etoposide. © 2007 Wiley-Liss, Inc. [source] Characterization of a human fetal spinal cord stem cell line, NSI-566RSC, and its induction to functional motoneuronsJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 3 2010Xiufang Guo Abstract Specific neuronal subtypes, especially motoneurons (MNs), derived from human stem cells provide a significant therapeutic potential for spinal cord diseases, such as amyotrophic lateral sclerosis (ALS) and spinal cord injury. So far, in vitro, MNs have only been successfully induced from embryonic stem cells (hESC) and human fetal cortical progenitors. Although neural progenitors from spinal cord would be a likely source for generating MNs, there has been no study reporting successful in vitro differentiation of MNs from spinal cord progenitors. This study first characterized a polyclonal spinal cord stem cell line isolated from an 8 week-old fetus. Then a paradigm was introduced to successfully induce MNs from this cell line, which was demonstrated by immunostaining using the MN markers HB9, Islet1 and choline acetyl transferase (ChAT). The combination of HB9 and ChAT immunostainings indicated that ,20% of the cells were MNs after this induction protocol. The presence of other cell types in the differentiated culture was also analysed. Finally, the electrophysiological properties of these differentiated MNs were characterized to confirm their functional integrity. The majority of these MNs fired repetitive action potentials (APs), which is an indicator of functional maturation. The recordings of spontaneous excitatory postsynaptic currents (EPSCs) confirmed the formation of synapses onto these MNs. This study reports the first successful differentiation of MNs from human spinal cord stem cells in vitro, providing a novel approach for obtaining functional MNs when designing the therapeutic strategy for spinal cord diseases or injuries. Copyright © 2009 John Wiley & Sons, Ltd. [source] Characterization and multilineage differentiation of embryonic stem cells derived from a buffalo parthenogenetic embryoMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 10 2007Hathaitip Sritanaudomchai Abstract Embryonic stem (ES) cells derived from mammalian embryos have the ability to form any terminally differentiated cell of the body. We herein describe production of parthenogenetic buffalo (Bubalus Bubalis) blastocysts and subsequent isolation of an ES cell line. Established parthenogenetic ES (PGES) cells exhibited diploid karyotype and high telomerase activity. PGES cells showed remarkable long-term proliferative capacity providing the possibility for unlimited expansion in culture. Furthermore, these cells expressed key ES cell-specific markers defined for primate species including stage-specific embryonic antigen-4 (SSEA-4), tumor rejection antigen-1-81 (TRA-1-81), and octamer-binding transcription factor 4 (Oct-4). In vitro, in the absence of a feeder layer, cells readily formed embryoid bodies (EBs). When cultured for an extended period of time, EBs spontaneously differentiated into derivatives of three embryonic germ layers as detected by PCR for ectodermal (nestin, oligodendrocytes, and tubulin), mesodermal (scleraxis, ,- skeletal actin, collagen II, and osteocalcin) and endodermal markers (insulin and ,- fetoprotein). Differentiation of PGES cells toward chondrocyte lineage was directed by supplementing serum-containing media with ascorbic acid, ,-glycerophosphate, and dexamethasone. Moreover, when PGES cells were injected into nude mice, teratomas with derivatives representing all three embryonic germ layers were produced. Our results suggest that the cell line isolated from a parthenogenetic blastocyst holds properties of ES cells, and can be used as an in vitro model to study the effects of imprinting on cell differentiation and as an a invaluable material for extensive molecular studies on imprinted genes. Mol. Reprod. Dev. 74: 1295,1302, 2007. © 2007 Wiley-Liss, Inc. [source] Derivation, characterization, and phenotypic variation of hepatic progenitor cell lines isolated from adult ratsHEPATOLOGY, Issue 2 2002Li Yin Liver progenitor cells (LPCs) cloned from adult rat livers following allyl alcohol injury express hematopoietic stem cell and early hepatic lineage markers when cultured on feeder layers; under these conditions, neither mature hepatocyte nor bile duct, Ito, stellate, Kupffer cell, or macrophage markers are detected. These phenotypes have remained stable without aneuploidy or morphological transformation after more than 100 population doublings. When cultured without feeder layers, the early lineage markers disappear, and mature hepatocyte markers are expressed; mature hepatocytic differentiation and cell size are also augmented by polypeptide and steroidal growth factors. In contrast to hepatocytic potential, duct-like structures and biliary epithelial markers are expressed on Matrigel. Because they were derived without carcinogens or mutagens, these bipotential LPC lines provide novel tools for models of cellular plasticity and hepatocarcinogenesis, as well as lines for use in cellular transplantation, gene therapy, and bioreactor construction. [source] Maintenance of clonal diversity during a spring bloom of the centric diatom Ditylum brightwelliiMOLECULAR ECOLOGY, Issue 6 2005TATIANA A. RYNEARSON Abstract Maintenance of genetic diversity in eukaryotic microbes reflects a synergism between reproductive mode (asexual vs. sexual) and environmental conditions. We determined clonal diversity in field samples of the planktonic marine diatom, Ditylum brightwellii, during a bloom, when cell number increased by seven-fold because of rapid asexual division. The genotypes at three microsatellite loci were determined for 607 individual cell lines isolated during the 11 days of sampling. Genetic diversity remained high during the bloom and 87% of the cells sampled each day were genetically distinct. Sixty-nine clonal lineages were sampled two or more times during the bloom, and two clones were sampled seven times. Based on the frequency of resampled clonal lineages, capture,recapture statistics were used to determine that at least 2400 genetically distinct clonal lineages comprised the bloom population. No significant differences in microsatellite allele frequencies were observed among daily samples indicating that the bloom was comprised of a single population. No sexual stages were observed, although linkage equilibrium at two loci, high levels of allelic and genotypic diversity, and heterozygote deficiencies were all indicative of past sexual reproduction events. At the height of the bloom, a windstorm diluted cell numbers by 51% and coincided with a change in the frequency distribution of some resampled lineages. The extensive clonal diversity generated through past sexual reproduction events coupled with frequent environmental changes appear to prevent individual clonal lineages from becoming numerically dominant, maintaining genetic diversity and the adaptive potential of the population. [source] | |||||||||||||