More than half of human cancers contain mutations in the tumor suppressor protein p53, most of which accumulate in the DNA binding domain of the protein. Here we report the identification of a mutant ...p53, designated p53–46F, in which Ser‐46 is replaced with phenylalanine. In vitro, adenovirus‐mediated transduction of the p53–46F gene induced apoptosis more efficiently than wild‐type p53 in a number of cancer cell lines, whereas Ser‐15 phosphorylation of p53–46F was enhanced in all cancer cell lines examined. Moreover, the expression level of the cell cycle inhibitor p21/WAF1 was decreased in cell lines infected with adenovirus p53–46F (Ad‐p53–46F). p53–46F caused a more enhanced level of transcriptional activation of several p53‐target genes, including Noxa, p53AIP1 and p53RFP, compared with wild‐type p53. In vivo, adenovirus‐mediated gene transfer of p53–46F enhanced apoptosis, thus suppressing tumor growth of a lung cancer cell line more effectively than wild‐type p53 or p53–121F, another p53 mutant. Collectively, our data suggest that p53–46F is an active version of p53 that demonstrates enhanced induction of p53‐dependent apoptosis. This is probably mediated by upregulated transactivation of genes downstream of p53, increased Ser‐15 phosphorylation and a decrease in p21/WAF1 levels. We propose p53–46F as an alternative candidate to wild‐type p53 for use in developing new therapeutic strategies for the treatment of cancer. (Cancer Sci 2006; 97: 633–641)
To understand comprehensive transcriptional profile of normal human fibroblast in response to irradiation.
To identify genes whose expression is influenced by gamma radiation, we used a cDNA ...microarray to analyze expression of 23,000 genes in normal human fibroblasts at 7 timepoints (1, 3, 6, 12, 24, 48, and 72 hours) after 5 different doses (0.5, 2, 5, 15, and 50 Gy) of exposure.
Among the genes that showed altered expression patterns, some were already known to be regulated by irradiation, for instance ODC, EGR1, FGF2, PCNA, PKC, and several p53-target genes, including p53DINP1, BTG2, GADD45, and MDM2. The time course of each dose showed that from 350 to 600 genes were affected as to their expression; induction profiles characteristic to each dose were demonstrated. Of the total identified, only 89 genes were up-regulated; the vast majority was down-regulated over the 72-hour time course. We identified 21 genes that were distinctly induced by irradiation; 11 of them were functionally known, and 6 of those were p53-target genes.
The results underscored the complexity of the transcriptional responses to irradiation, and the data should serve as a basis for global characterization of radiation-regulated genes and pathways.
The positive correlation between smoking and cancer risk is well estimated in sporadic colorectal cancer, whereas little is known with regard to Lynch syndrome-associated colorectal cancer. A total ...of 118 familial colorectal cancer patients from the Hereditary Nonpolyposis Colorectal Cancer Registry and Genetic Testing Project of the Japanese Society for Cancer of the Colon and Rectum, were assessed to determine whether smoking alters the incidence of multiple colorectal cancers. In male patients with Lynch syndrome (n = 29), the incidence of multiple colorectal cancers in patients who had ever smoked (smoking duration: median of 19 years) was higher than that in those who never smoked (58.8% vs. 10.0%, P = 0.02). The cumulative risk for metachronous colorectal cancer was significantly higher in male Lynch syndrome patients who had previously smoked than in those who had never smoked (P = 0.03). Our data suggest that long-term cigarette smoking might be a strong risk factor for the development of multiple colorectal cancers in male Lynch syndrome patients.
In our research work, we are focusing on bamboo due to its advantages of fast growth, renewability, flexibility, low cost, and high specific strength and stiffness which can be frequently compared ...with glass fiber. We have proposed a novel hot press fabrication method of binder-free green composite products made of bamboo fibers extracted by end-milling with a machining center. Lignin could serve as a bonding material to make the bamboo fiber self-bonded itself by hot press forming to fabricate our green composite from pure 100% bamboo fiber without any binder materials because its extracted fibers are hardly damaged with a machining center. In our previous studies, we have developed a hot press forming method to fabricate two-dimensional small and simple shape products based on bamboo fiber self-bonded technology. In the present report, we propose a novel two-step hot press forming method based on two kinds of dies to fabricate three-dimensional shape products. Especially, we focus on hemisphere shell shape products because a hemispherical conical cup press forming test is frequently used to estimate the press forming performance of a kind of complex plate products. As a result, the proposed two-step concept of hot press forming is found to be effective to fabricate the three-dimensional shell shape product made of pure 100% bamboo fibers. It can be also seen that a suitable treatment between first and second step is considered important because it aids effective action due to liquid flow performance and the plastic zone of molding material.
Gastric cancer is the fourth leading cause of cancer-related death in the world. Two histologically distinct types of gastric carcinoma, 'intestinal' and 'diffuse', have different epidemiological and ...pathophysiological features that suggest different mechanisms of carcinogenesis. A number of studies have investigated intestinal-type gastric cancers at the molecular level, but little is known about mechanisms involved in the diffuse type, which has a more invasive phenotype and poorer prognosis. To clarify the mechanisms that underlie its development and/or progression, we compared the expression profiles of 20 laser-microbeam-microdissected diffuse-type gastric-cancer tissues with corresponding noncancerous mucosae by means of a cDNA microarray containing 23,040 genes. We identified 153 genes that were commonly upregulated and more than 1500 that were commonly downregulated in the tumors. We also identified a number of genes related to tumor progression. Furthermore, comparison of the expression profiles of diffuse-type with those of intestinal-type gastric cancers identified 46 genes that may represent distinct molecular signatures of each histological type. The putative signature of diffuse-type cancer exhibited altered expression of genes related to cell-matrix interaction and extracellular-matrix (ECM) components, whereas that of intestinal-type cancer represented enhancement of cell growth. These data provide insight into different mechanisms underlying gastric carcinogenesis and may also serve as a starting point for identifying novel diagnostic markers and/or therapeutic targets for diffuse-type gastric cancers.
Interferon regulatory factors (IRFs) regulate transcription of interferon genes through DNA sequence-specific binding to these targets. Using a differential display method for examining gene ...expression in p53-defective cells infected with adenovirus containing wild-type p53, we found that expression of interferon regulatory factor 5 (IRF-5) mRNA was increased in the presence of exogenous p53. An electrophoretic mobility-shift assay showed that a potential p53 binding site (p53BS) detected in exon 2 of the IRF-5 gene could in fact bind to p53 protein. Moreover, a heterologous reporter assay revealed that the p53BS possessed p53-dependent transcriptional activity. Expression of IRF-5 was induced in p53+/+ cells (MCF7 and NHDF), but not inp53-/- cells (H1299) when DNA was damaged by gamma-irradiation, UV-radiation, or adriamycin treatment in a wild-type p53-dependent manner. These results suggest that IRF-5 is a novel p53-target, and that it might mediate the p53-dependent immune response.
The aim of this study is to identify novel molecular targets for development of novel treatment or diagnostic markers of prostate cancer through genome-wide cDNA microarray analysis of prostate ...cancer cells purified by laser microdissection.
Here, we identified molecule interacting with CasL-2 prostate cancer variants (MICAL2-PV), novel splicing variants of MICAL2, showing overexpression in prostate cancer cells. Immunohistochemical analysis using an antibody generated specific to MICAL2-PV revealed that MICAL2-PV was expressed in the cytoplasm of cancer cells with various staining patterns and intensities, whereas it was not or hardly detectable in adjacent normal prostate epithelium or prostatic intraepithelial neoplasia. Interestingly, immunohistochemical analysis of 105 prostate cancer specimens on the tissue microarray indicated that MICAL2-PV expression status was strongly correlated with Gleason scores (P < 0.0001) or tumor classification (P < 0.0001). Furthermore, the expression levels of MICAL2-PVs were also concordant to those of c-Met, a marker of tumor progression, with statistical significance (P = 0.0018). To investigate its potential of molecular therapeutic target for prostate cancers, we knocked down endogenous MICAL2-PVs in prostate cancer cells by small interfering RNA, which resulted in the significant reduction of prostate cancer cell viability.
Our findings suggest that MICAL2-PV is likely to be involved in cancer progression of prostate cancer and could be a candidate as a novel molecular marker and/or target for treatment of prostate cancers with high Gleason score.
Aim: Peripheral arterial disease (PAD) is a common cause of cardiovascular morbidity and an inde-pendent predictor of cardiovascular mortality. However, little is known about the genetic basis of ...PAD. To elucidate this, we performed a two-staged genome-wide association study in Japanese indi-viduals. Methods: We initially tested 222,285 single-nucleotide polymorphisms (SNPs). After the first screen-ing in a panel of 195 PAD cases and 1,358 controls, 2,696 SNPs (1.2%) were further genotyped in the second screening using another panel of 699 PAD cases and 1540 controls. In both screenings, controls were subjects affected with some diseases other than PAD. Results: When analyzed in the combined panel, the strongest signal of PAD association was observed at rs1902341 in the intron of OSBPL10 (p=4.7E-7 for trend test; OR=1.31, 95% CI 1.18-1.46). Also, PAD was modestly associated at several other loci such as rs2554503 in CSMD1 (p=5.7E-5; OR=1.32, 95% CI 1.15-1.51) or rs235243 in VSP13D (p=0.04; OR=1.18, 95% CI 1.01-1.37). Conclusion: Our genome-wide exploration identified suggestive evidence of PAD association at the OSBPL10 locus. Because the association has not reached a genome-wide significant level, further replication study is warranted for verification in the Japanese population.
Although the Japanese population has a rather low genetic diversity, we recently confirmed the presence of two main clusters (the Hondo and Ryukyu clusters) through principal component analysis of ...genome-wide single-nucleotide polymorphism (SNP) genotypes. Understanding the genetic differences between the two main clusters requires further genome-wide analyses based on a dense SNP set and comparison of haplotype frequencies. In the present study, we determined haplotypes for the Hondo cluster of the Japanese population by detecting SNP homozygotes with 388,591 autosomal SNPs from 18,379 individuals and estimated the haplotype frequencies. Haplotypes for the Ryukyu cluster were inferred by a statistical approach using the genotype data from 504 individuals. We then compared the haplotype frequencies between the Hondo and Ryukyu clusters. In most genomic regions, the haplotype frequencies in the Hondo and Ryukyu clusters were very similar. However, in addition to the human leukocyte antigen region on chromosome 6, other genomic regions (chromosomes 3, 4, 5, 7, 10 and 12) showed dissimilarities in haplotype frequency. These regions were enriched for genes involved in the immune system, cell-cell adhesion and the intracellular signaling cascade. These differentiated genomic regions between the Hondo and Ryukyu clusters are of interest because they (1) should be examined carefully in association studies and (2) likely contain genes responsible for morphological or physiological differences between the two groups.
The recent clinical application of granulocyte macrophage colony‐stimulating factor (GM‐CSF)‐transduced autologous tumor vaccines revealed substantial antitumor activity and valuable clinical ...results. However, for these vaccines to be optimally effective, the antitumor efficacies must be improved. Recently, Sendai virus (SeV) vectors, which are cytoplasmic RNA vectors, have emerged as safe vectors with high gene transduction. In the current study, the in vivo therapeutic antitumor efficacies of irradiated GM‐CSF‐transduced mouse renal cell carcinoma (RENCA) vaccine cells mediated by either fusion gene‐deleted non‐transmissible SeV encoding mouse GM‐CSF (SeV/dF/G) or adenovirus (E1, E3 deleted serotype 5 adenovirus) encoding mouse GM‐CSF (AdV/G) (respectively described as irRC/SeV/GM or irRC/AdV/GM) were compared in RENCA‐bearing mice. The results showed that the antitumor effect was equivalent between irRC/SeV/GM and irRC/AdV/GM cells, even though the former produced less GM‐CSF in vitro. The cell numbers of activated (CD80+, CD86+, CD80+CD86+) dendritic cells in lymph nodes from mice treated with irRC/AdV/GM or irRC/SeV/GM cells were increased significantly compared with those of mice treated with the respective controls, at both the earlier and later phases. In an in vitro cytotoxicity assay, splenocytes harvested from mice treated with both irRC/SeV/GM and irRC/AdV/GM cells showed tumor‐specific responses against RENCA cells. The restimulated splenocytes harvested from mice treated with irRC/SeV/GM or irRC/AdV/GM cells produced significantly higher levels of interleukin‐2, interleukin‐4, and interferon‐γ compared with their respective controls (P < 0.05). Furthermore, vaccination with irRC/AdV/GM or irRC/SeV/GM cells induced significantly enhanced recruitment of the cytolytic effectors of CD107a+CD8+ T cells and CD107a+ natural killer cells into tumors compared with those induced by their respective controls (P < 0.05). Taken together, our results suggest that the SeV/dF/G vector is a potential candidate for the production of effective autologous GM‐CSF‐transduced tumor vaccines in clinical cancer immune gene therapy. (Cancer Sci 2008; 99: 2315–2326)
PDF
