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Tadashi Kadowaki

Publications and source records attributed to Tadashi Kadowaki.

6 recordsLinked to original sources

Developmental aberrations of liver gene expression in bovine fetuses derived from somatic cell nuclear transplantation.

Cloning by somatic cell nuclear transfer (NT) has been accomplished. However, the process itself is inefficient since most clones die before birth and survivors often display various anomalies. In an effort to determine global expression profiles of developmentally regulated liver genes in NT bovine fetuses, we employed a custom-made bovine liver complementary DNA (cDNA) microarray. The NT fetuses in early pregnancy were derived from cumulus cells as the nuclear donor cells. Normal fetuses were derived from in vitro fertilization (IVF) and artificial insemination (AI). Gene expression levels in NT, IVF, and AI fetal livers were obtained by comparing individual fetal liver samples with that of adult liver of nonpregnant cycling cows. Statistical analyses of the expression data showed widespread dysregulation of developmentally important genes in the three NT fetuses examined. It was found that the number of dysregulated genes was within a range of 3.5-7.7% of the tested genes in the NT fetal livers. The analyses revealed that one NT fetus was markedly different in liver gene expression profile from the other two NT fetal livers in which the expression profiles were highly correlated. Thus, our findings demonstrate that widespread dysregulation of liver genes occurs in the developing liver of NT bovine fetuses. It is possible that inappropriate genomic reprogramming after NT is a key factor associated with abnormal gene expressions in the livers of NT fetuses, whereas distinct expression patterns between the fellow cloned fetuses likely have resulted from variable epigenetic status of the donor nuclei.

Animals↗

High throughput comparative genomic hybridization array analysis of multifocal urothelial cancers.

The purpose of this study was to examine genetic alterations occur during synchronous or metachronous multifocal development of urothelial cancers on the whole genome using a comparative genomic hybridization (CGH) array. We used 10 tumor pairs (2 tumors for each patient), in which we had previously defined a clonal relationship by microsatellite analysis. For CGH array analysis, Vysis GenoSensor Array 300 kit was used. An unsupervised hierarchical cluster analysis revealed that the tumors from one patient were clustered together independent of the tumors of all other patients. On the other hand, many genetic divergences among multifocal urothelial cancers were newly found by a CGH array analysis. The concordant genetic alteration patterns of the chromosomal arm in tumor pairs were most frequently observed in 9p, 9q, 8p, 7p, 7q and 11q, while discordant patterns were most frequently found in 15q, 20q, 2q, 10p and 11q. Investigation using a CGH array showed that genetically stable multifocal tumors were less frequent, and that a large percentage of urothelial cancers accumulate genetic alterations during multifocal development by clonal evolution. We might have to consider these genetic accumulations during multifocal development when designing strategies for prevention and detection of recurrent multifocal urothelial cancers. CGH array can be a powerful tool for genetic analysis of multifocal urothelial cancer.

Chromosome Aberrations↗

Inhibition of protein kinase CK2 prevents the progression of glomerulonephritis.

Glomerulonephritis (GN) is a progressive inflammation that may be caused by a variety of underlying disorders. It is the primary cause of chronic renal failure and end-stage renal disease, which require dialysis and transplantation worldwide. Immunosuppressive therapy has been used to treat GN clinically, but this treatment has had insufficient therapeutic effects. Here, we show that protein kinase CK2 is a key molecule in the progression of GN. cDNA microarray analysis identified CK2alpha, the catalytic subunit of CK2, as a GN-related, differentially expressed gene. Overexpression of CK2alpha was noted in the proliferative glomerular lesions in rat GN models and in renal biopsy specimens from lupus nephritis or IgA nephropathy patients. Administration of either antisense oligodeoxynucleotide against CK2alpha or low molecular weight CK2-specific inhibitors effectively prevented the progression of renal pathology in the rat GN models. The resolution of GN by CK2 inhibition may result from its suppression of extracellular signal-regulated kinase-mediated cell proliferation, and its suppression of inflammatory and fibrotic processes that are enhanced in GN. Our results show that CK2 plays a critical role in the progression of immunogenic renal injury, and therefore, CK2 is a potential target for GN therapy.

Analysis of Variance↗

Gene expression profile in experimental mesangial proliferative glomerulonephritis.

We analyzed gene expression in rat anti-Thy1 antibody-induced glomerulonephritis by using the cDNA microarray method. Ninety-seven genes that differed by more than 1.5-fold intensity in comparison with the controls were selected. Cluster analysis showed that the expression of genes associated with inflammation reached maximum levels at 24 h, while genes involved in the development of fibrosis increased at 7 days after injection. Microarray analysis of animal disease models may be a powerful approach for understanding the gene expression programs that underlie these disorders.

Animals↗

Pregnancy-associated changes in genome-wide gene expression profiles in the liver of cow throughout pregnancy.

The objective of the present study was to fabricate and use a bovine liver complementary DNA (cDNA) microarray to profile genome-wide gene expressions in the liver of cow throughout pregnancy. A cDNA library was prepared from liver total RNA collected from cows during estrous cycle and pregnancy, and from fetuses at different stages of pregnancy. The sequenced clones were compiled and annotated by basic local alignment search tool (BLASTn) and spotted onto glass slides. The annotated liver array represented 2675 genes. Of which, 1442 were known genes while 617 sequences had matches with sequences found in expressed sequence tags databases. In addition, 616 unknown sequences were found and these sequences may possibly be identified as candidates for novel bovine genes. For gene expression profiling studies, total RNA from livers of cows slaughtered on days 19, 27-28, 49-58, 150, and 245 of pregnancy (test RNAs) was separately reverse transcribed and labeled with either cyanine 5-fluorescent dye (Cy5) or Cy3. The test samples were individually compared with liver total RNA collected from nonpregnant cycling cows (control RNA) after reverse transcription and labeling with the opposite dye following a two-color hybridization method. After scanning, image acquisition, and normalization, genes that showed either more than 1.5-fold (test/control) induction or repression were selected for further analyses. Hierarchical clustering algorithm showed a clear induction of most liver genes on days 27-28 of pregnancy. Self-organizing maps algorithm identified groups of genes whose differential expression patterns were similar across pregnancy. In conclusion, we described fabrication of a bovine liver cDNA microarray, and demonstrate, for the first time, differential expression patterns of a large number of coregulated liver genes in parallel throughout pregnancy in the bovine.

Algorithms↗