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51.
Novel thienopyridine derivatives 1b1r were synthesized, based on a hit compound 1a that was found in a previous cell-based screening of anticancer drugs. Compounds 1a1r have the following features: (1) their anticancer activity in vitro was first reported by our group. (2) The most potent analog 1g possesses hepatocellular carcinoma (HCC)-specific anticancer activity. It can specifically inhibit the proliferation of the human hepatoma HepG2 cells with an IC50 value of 0.016 μM (compared with doxorubicin as a positive control, whose IC50 was 0.37 μM). It is inactive toward a panel of five different types of human cancer cell lines. (3) Compound 1g remarkably induces G0/G1 arrest and apoptosis in HepG2 cells in vitro at low micromolar concentrations. These results, especially the HCC-specific anticancer activity of 1g, suggest their potential in targeted chemotherapy for HCC.  相似文献   
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Wulf G  Garg P  Liou YC  Iglehart D  Lu KP 《The EMBO journal》2004,23(16):3397-3407
Phosphorylation on certain Ser/Thr-Pro motifs is a major oncogenic mechanism. The conformation and function of phosphorylated Ser/Thr-Pro motifs are further regulated by the prolyl isomerase Pin1. Pin1 is prevalently overexpressed in human cancers and implicated in oncogenesis. However, the role of Pin1 in oncogenesis in vivo is not known. We have shown that Pin1 ablation is highly effective in preventing oncogenic Neu or Ras from inducing cyclin D1 and breast cancer in mice, although it neither affects transgene expression nor mammary gland development. Moreover, we have developed an ex vivo assay to uncover that a significant fraction of primary mammary epithelial cells from Neu or Ras mice display various malignant properties long before they develop tumors in vivo. Importantly, these early transformed properties are effectively suppressed by Pin1 deletion, which can be fully rescued by overexpression of cyclin D1. Thus, Pin1 is essential for tumorigenesis and is an attractive anticancer target. Our ex vivo assay can be used to study early events of breast cancer development in genetically predisposed mice.  相似文献   
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Wu CM  Chen HL  Liou W  Lin TL  Jeng US 《Biomacromolecules》2004,5(6):2324-2328
Liposome consisting of a single zwitterionic lipid as the potential vector for gene therapy has been reported recently; however, whether polyanionic DNA can bind directly with zwitterionic lipid without the aid of multivalent salt still remains unresolved. In this study, we reveal the aggregation of zwitterionic oligolamellar liposomes composed of 1,2-di(cis-9-octadecenoyl)-sn-glycero-3-phosphocholine induced by DNA without the presence of multivalent salt. Our results demonstrate that only a small fraction (<10%) of DNA can bind electrostatically with a portion of the liposomes. Such a low degree of binding, however, induces significant aggregation of these oligolamellar liposomes, yielding large multilamellar particles in which the number of hydrophilic/hydrophobic layer stacking becomes sufficiently large to yield multiple diffraction peaks in the small-angle X-ray scattering profile. Addition of monovalent salt such as NaCl tends to disrupt the multilamellar structure.  相似文献   
55.
Microarray technology was used to gain an insight into the molecular events of tumor cell growth inhibition mediated by the soy isoflavone genistein. For this, a susceptible bladder tumor line TCCSUP was treated with the inhibitory dose (50 microM) of genistein for various periods of time, followed by mRNA isolations, cDNA probe preparations, and hybridization individually to cDNA chips containing 884 sequence-verified known human genes. After analyzing the hybridization signals with a simple quantitative method developed by this study, we detected that egr-1, whose expression has been associated with proliferation and differentiation, was transiently induced and this expression pattern was later confirmed by RT-PCR. Thus, microarray technology is a reliable and powerful tool for profiling gene expression patterns in many biological systems related to cancer. We further detected many groups of genes with distinct expression profiles and most of them encode for proteins that regulate the signal transduction or the cell cycle pathways. These genes warrant further investigation as regards their roles in the susceptibility of the tumor cell line to the antitumor drug.  相似文献   
56.
Genes homologous to 2-deoxystreptamine (DOS) biosynthetic genes were isolated from aminoglycoside producers, Micromonospora and Streptomyces spp., using PCR primers based on the core sequences of 2-deoxy-scyllo-inosose (DOI) synthase and L-glutamine: scyllo-inosose aminotransferase (GIA). Identities of 40-45% were observed for DOI synthases, and 65-75% were observed for GIAs. The gene cluster of tobramycin biosynthesis was isolated from the genomic library of Streptomyces tenebrarius using DOI synthase as a probe. Sequencing of 33.9 kb revealed 24 putative open reading frames including the tobramycin biosynthetic gene cluster (13.8 kb) and a transport protein. This cluster encodes proteins homologous to 2-deoxystreptamine biosynthetic enzymes, glycosyltransferase and other aminocyclitols biosynthetic enzymes. Sequence analysis revealed the evolution of DOI synthases from 3-dehydroquinate (DHQ) synthases in actinomycetes. DOI synthases and GIA are therefore useful for cloning biosynthetic genes of DOS-containing aminocyclitol antibiotics or for screening such metabolites producers.  相似文献   
57.
The purpose of this study was to assess the progressive changes of nasal symmetry, growth, and relapse after presurgical nasoalveolar molding and primary cheiloplasty in unilateral complete cleft lip/palate infants. Twenty-five consecutive complete unilateral cleft lip/palate infants were included. All the infants underwent nasoalveolar molding before primary cheiloplasty. Standard 1:1 ratio basilar photographs were taken before and after nasoalveolar molding, 1 week after cheiloplasty, and yearly for 3 years. Linear measurements were made directly on the photographs. The results of this study revealed that the nasal asymmetry was significantly improved after nasoalveolar molding and was further corrected to symmetry after primary cheiloplasty. After the primary cheiloplasty, the nasal asymmetry significantly relapsed in the first year postoperatively and then remained stable and well afterward. The relapse was the result of a significant differential growth between the cleft and noncleft sides in the first year postoperatively. To compensate for relapse and differential growth, the authors recommend (1) narrowing down the alveolar cleft as well as possible by nasoalveolar molding, (2) overcorrecting the nasal vertical dimension surgically, and (3) maintaining the surgical results using a nasal conformer.  相似文献   
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The polymorphisms in the human leukocyte antigen (HLA) region are powerful tool for studying human evolutionary processes. We investigated genetic structure of Japanese by using five-locus HLA genotypes (HLA-A, -B, -C, -DRB1, and -DPB1) of 2,005 individuals from 10 regions of Japan. We found a significant level of population substructure in Japanese; particularly the differentiation between Okinawa Island and mainland Japanese. By using a plot of the principal component scores, we identified ancestry informative alleles associated with the underlying population substructure. We examined extent of linkage disequilibrium (LD) between pairs of HLA alleles on the haplotypes that were differentiated among regions. The LDs were strong and weak for pairs of HLA alleles characterized by low and high frequencies in Okinawa Island, respectively. The five-locus haplotypes whose alleles exhibit strong LD were unique to Japanese and South Korean, suggesting that these haplotypes had been recently derived from the Korean Peninsula. The alleles characterized by high frequency in Japanese compared to South Korean formed segmented three-locus haplotype that was commonly found in Aleuts, Eskimos, and North- and Meso-Americans but not observed in Korean and Chinese. The serologically equivalent haplotype was found in Orchid Island in Taiwan, Mongol, Siberia, and Arctic regions. It suggests that early Japanese who existed prior to the migration wave from the Korean Peninsula shared ancestry with northern Asian who moved to the New World via the Bering Strait land bridge. These results may support the admixture model for peopling of Japanese Archipelago.  相似文献   
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