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Ken Koshiba - One of the best experts on this subject based on the ideXlab platform.
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Genomic Instability of Microsatellite Repeats in Prostate Cancer: Relationship to Clinicopathological Variables
Cancer research, 1995Co-Authors: Shin Egawa, Toyoaki Uchida, Kazuho Suyama, Chunxi Wang, Makoto Ohori, Satoshi Irie, Masatsugu Iwamura, Ken KoshibaAbstract:Sixty-six patients with prostatic adenocarcinoma were screened for somatic instability at 8 Microsatellite marker loci on 5 chromosomes. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 13 (19.7%) patients. Only extraglandular spread (nodal involvement and distant metastasis) was found to show significant association with somatic instability after controlling for other clinicopathological variables (P < 0.05). Microsatellite instability may possibly occur during the early stages of neoplastic transformation in a subset of prostate cancer rather than as a late event. This may be related to a phenotype with growth advantage. The frequency of this mutator phenotype is much higher in the United States than Japan, reflecting racial differences in the molecular tumorigenesis of this malignancy.
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ALTERATIONS OF Microsatellite Repeats IN BLADDER-CANCER
Oncology reports, 1994Co-Authors: Toyoaki Uchida, Chieki Wada, Hironori Ishida, Shin Egawa, Eiji Yokoyama, Toru Kameya, Hideki Ohtani, Ken KoshibaAbstract:Investigation of the genomic instability of Microsatellite Repeats indicates a new mechanism for human carcinogenesis. This study was conducted to determine whether such alterations in Microsatellite Repeats are associated with the onset of bladder cancer. Thirty-two primary bladder cancer DNA samples were examined for genomic instability at (CA)n Repeats on human chromosomes 5q (D5S107), 17p (D17S261) and 18q (DCC) by polymerase chain reaction (PCR) assay. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 6 of the 32 (18.8%) tumors examined. These six tumors were beyond grade 2 and stage pT2 invasive bladder tumors. However, only one of 32 (3.1%) showed alterations with more than 2 Microsatellite probes. It follows that alterations of (CA)n Microsatellite instability may be infrequent in the tumorigenesis of bladder cancer.
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genomic instability of Microsatellite Repeats and mutations of h k and n ras and p53 genes in renal cell carcinoma
Cancer Research, 1994Co-Authors: Toyoaki Uchida, Chieki Wada, Shin Egawa, Hideki Ohtani, Chunxi Wang, Ken KoshibaAbstract:Abstract Thirty-six primary renal cell carcinoma samples and one metastatic lymph node DNA sample were examined for mutations of H-, K-, and N- ras and p53 genes, and genomic instability at (AC) n , (CA) n ·(GT) n , and (TA) n ·(GT) n Repeats. No mutations were noted for H-, K-, and N- ras gene and only 2 of all the samples (5.6%) showed mutations at exon 8 of the p53 gene. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 9 (25.0%) of the cases examined. Somatic alterations in seven Microsatellites, D3S1228, D3S643, D5S107, LPL5GT, D9S63, D17S261 , and DCC , were found in 1 (2.8%), 3 (8.3%), 2 (5.7%), 5 (14.7%), 3 (8.3%), 3 (8.3%), and 3 (8.3%) cases, respectively. Five of 26 (19.2%) clear cell type and 4 of 10 (40.0%) non-clear cell type patients showed DNA instability. Two of 11 (18.2%) grade 1, 5 of 20 (25.0%) grade 2, and 2 of 5 (40.0%) grade 3 patients showed abnormal patterns. One of 2 (50.0%) stage pT 1 , 4 of 24 (16.7%) stage pT 2 , and 4 of 10 (40.0%) stage pT 3 patients were shown to have Microsatellite instability. In 4 of 9 alteration-positive cases (44.4%), mutations in multiple Microsatellites were observed. Alterations in Microsatellite instability may be more common in non-clear cell type, high-grade, and high-stage renal cell carcinoma patients.
Shin Egawa - One of the best experts on this subject based on the ideXlab platform.
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Genomic Instability of Microsatellite Repeats in Prostate Cancer: Relationship to Clinicopathological Variables
Cancer research, 1995Co-Authors: Shin Egawa, Toyoaki Uchida, Kazuho Suyama, Chunxi Wang, Makoto Ohori, Satoshi Irie, Masatsugu Iwamura, Ken KoshibaAbstract:Sixty-six patients with prostatic adenocarcinoma were screened for somatic instability at 8 Microsatellite marker loci on 5 chromosomes. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 13 (19.7%) patients. Only extraglandular spread (nodal involvement and distant metastasis) was found to show significant association with somatic instability after controlling for other clinicopathological variables (P < 0.05). Microsatellite instability may possibly occur during the early stages of neoplastic transformation in a subset of prostate cancer rather than as a late event. This may be related to a phenotype with growth advantage. The frequency of this mutator phenotype is much higher in the United States than Japan, reflecting racial differences in the molecular tumorigenesis of this malignancy.
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ALTERATIONS OF Microsatellite Repeats IN BLADDER-CANCER
Oncology reports, 1994Co-Authors: Toyoaki Uchida, Chieki Wada, Hironori Ishida, Shin Egawa, Eiji Yokoyama, Toru Kameya, Hideki Ohtani, Ken KoshibaAbstract:Investigation of the genomic instability of Microsatellite Repeats indicates a new mechanism for human carcinogenesis. This study was conducted to determine whether such alterations in Microsatellite Repeats are associated with the onset of bladder cancer. Thirty-two primary bladder cancer DNA samples were examined for genomic instability at (CA)n Repeats on human chromosomes 5q (D5S107), 17p (D17S261) and 18q (DCC) by polymerase chain reaction (PCR) assay. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 6 of the 32 (18.8%) tumors examined. These six tumors were beyond grade 2 and stage pT2 invasive bladder tumors. However, only one of 32 (3.1%) showed alterations with more than 2 Microsatellite probes. It follows that alterations of (CA)n Microsatellite instability may be infrequent in the tumorigenesis of bladder cancer.
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genomic instability of Microsatellite Repeats and mutations of h k and n ras and p53 genes in renal cell carcinoma
Cancer Research, 1994Co-Authors: Toyoaki Uchida, Chieki Wada, Shin Egawa, Hideki Ohtani, Chunxi Wang, Ken KoshibaAbstract:Abstract Thirty-six primary renal cell carcinoma samples and one metastatic lymph node DNA sample were examined for mutations of H-, K-, and N- ras and p53 genes, and genomic instability at (AC) n , (CA) n ·(GT) n , and (TA) n ·(GT) n Repeats. No mutations were noted for H-, K-, and N- ras gene and only 2 of all the samples (5.6%) showed mutations at exon 8 of the p53 gene. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 9 (25.0%) of the cases examined. Somatic alterations in seven Microsatellites, D3S1228, D3S643, D5S107, LPL5GT, D9S63, D17S261 , and DCC , were found in 1 (2.8%), 3 (8.3%), 2 (5.7%), 5 (14.7%), 3 (8.3%), 3 (8.3%), and 3 (8.3%) cases, respectively. Five of 26 (19.2%) clear cell type and 4 of 10 (40.0%) non-clear cell type patients showed DNA instability. Two of 11 (18.2%) grade 1, 5 of 20 (25.0%) grade 2, and 2 of 5 (40.0%) grade 3 patients showed abnormal patterns. One of 2 (50.0%) stage pT 1 , 4 of 24 (16.7%) stage pT 2 , and 4 of 10 (40.0%) stage pT 3 patients were shown to have Microsatellite instability. In 4 of 9 alteration-positive cases (44.4%), mutations in multiple Microsatellites were observed. Alterations in Microsatellite instability may be more common in non-clear cell type, high-grade, and high-stage renal cell carcinoma patients.
Toyoaki Uchida - One of the best experts on this subject based on the ideXlab platform.
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Genomic Instability of Microsatellite Repeats in Prostate Cancer: Relationship to Clinicopathological Variables
Cancer research, 1995Co-Authors: Shin Egawa, Toyoaki Uchida, Kazuho Suyama, Chunxi Wang, Makoto Ohori, Satoshi Irie, Masatsugu Iwamura, Ken KoshibaAbstract:Sixty-six patients with prostatic adenocarcinoma were screened for somatic instability at 8 Microsatellite marker loci on 5 chromosomes. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 13 (19.7%) patients. Only extraglandular spread (nodal involvement and distant metastasis) was found to show significant association with somatic instability after controlling for other clinicopathological variables (P < 0.05). Microsatellite instability may possibly occur during the early stages of neoplastic transformation in a subset of prostate cancer rather than as a late event. This may be related to a phenotype with growth advantage. The frequency of this mutator phenotype is much higher in the United States than Japan, reflecting racial differences in the molecular tumorigenesis of this malignancy.
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ALTERATIONS OF Microsatellite Repeats IN BLADDER-CANCER
Oncology reports, 1994Co-Authors: Toyoaki Uchida, Chieki Wada, Hironori Ishida, Shin Egawa, Eiji Yokoyama, Toru Kameya, Hideki Ohtani, Ken KoshibaAbstract:Investigation of the genomic instability of Microsatellite Repeats indicates a new mechanism for human carcinogenesis. This study was conducted to determine whether such alterations in Microsatellite Repeats are associated with the onset of bladder cancer. Thirty-two primary bladder cancer DNA samples were examined for genomic instability at (CA)n Repeats on human chromosomes 5q (D5S107), 17p (D17S261) and 18q (DCC) by polymerase chain reaction (PCR) assay. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 6 of the 32 (18.8%) tumors examined. These six tumors were beyond grade 2 and stage pT2 invasive bladder tumors. However, only one of 32 (3.1%) showed alterations with more than 2 Microsatellite probes. It follows that alterations of (CA)n Microsatellite instability may be infrequent in the tumorigenesis of bladder cancer.
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genomic instability of Microsatellite Repeats and mutations of h k and n ras and p53 genes in renal cell carcinoma
Cancer Research, 1994Co-Authors: Toyoaki Uchida, Chieki Wada, Shin Egawa, Hideki Ohtani, Chunxi Wang, Ken KoshibaAbstract:Abstract Thirty-six primary renal cell carcinoma samples and one metastatic lymph node DNA sample were examined for mutations of H-, K-, and N- ras and p53 genes, and genomic instability at (AC) n , (CA) n ·(GT) n , and (TA) n ·(GT) n Repeats. No mutations were noted for H-, K-, and N- ras gene and only 2 of all the samples (5.6%) showed mutations at exon 8 of the p53 gene. Differences in unrelated Microsatellites for tumor and normal DNA were detected in 9 (25.0%) of the cases examined. Somatic alterations in seven Microsatellites, D3S1228, D3S643, D5S107, LPL5GT, D9S63, D17S261 , and DCC , were found in 1 (2.8%), 3 (8.3%), 2 (5.7%), 5 (14.7%), 3 (8.3%), 3 (8.3%), and 3 (8.3%) cases, respectively. Five of 26 (19.2%) clear cell type and 4 of 10 (40.0%) non-clear cell type patients showed DNA instability. Two of 11 (18.2%) grade 1, 5 of 20 (25.0%) grade 2, and 2 of 5 (40.0%) grade 3 patients showed abnormal patterns. One of 2 (50.0%) stage pT 1 , 4 of 24 (16.7%) stage pT 2 , and 4 of 10 (40.0%) stage pT 3 patients were shown to have Microsatellite instability. In 4 of 9 alteration-positive cases (44.4%), mutations in multiple Microsatellites were observed. Alterations in Microsatellite instability may be more common in non-clear cell type, high-grade, and high-stage renal cell carcinoma patients.
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Genomic instability of Microsatellite Repeats and its association with the evolution of chronic myelogenous leukemia.
Blood, 1994Co-Authors: Chieki Wada, Toyoaki Uchida, Shigeru Shionoya, Yumi Fujino, Hideo Tokuhiro, Tohru Akahoshi, Hideki OhtaniAbstract:Tumorigenesis has been shown to proceed through a series of genetic alterations involving protooncogenes and tumor-suppressor genes. Investigation of genomic instability of Microsatellites has indicated a new mechanism for human carcinogenesis in hereditary nonpolyposis colorectal cancer and sporadic cancer and this instability has been shown to be related to inherited predisposition to cancer. This study was conducted to determine whether such Microsatellite instability is associated with the evolution of chronic myelogenous leukemia (CML) to the blast crisis. Nineteen CML patients clinically progressing from the chronic phase to accelerated phase or blast crisis and 20 other patients in the CML chronic phase were studied. By polymerase chain reaction assay, DNAs for genomic instability in five separate Microsatellites in chromosome arms 5q (Mfd27), 17p (Mfd41), 18q (DCC), 3p (CI3-9), and 8p (LPL) were examined. Differences in unrelated Microsatellites of chronic and blastic phase DNAs in 14 of 19 patients (73.7%) were demonstrated. Somatic instability in five Microsatellites, Mfd27, Mfd41, DCC, CI3-9, and LPL, was detected in 2 of 19 (10.5%), 8 of 19 (42.1%), 11 of 19 (57.9%), 4 of 17 (23.5%), and 4 of 17 (23.5%) cases. In 10 of 19 cases (52.6%), genetic instability in at least two of five Microsatellites was observed and was categorized as replication error (RER+) phenotype. CML evolution cases with myeloid, lymphoid, and mixed phenotypes and the blast crisis and accelerated phase showed somatic instability in a number of Microsatellites. No alterations in leukemic cells at the chronic phase could be detected in any Microsatellites. These data indicate instability of Microsatellites (RER+) but not familial predisposition to possibly be a late genetic event in the evolution of CML to blast crisis. In the Microsatellite of the DCC gene, complicated alterations in band patterns caused by instability as well as loss of heterozygosity (LOH) were observed in 13 of 19 cases (68.4%): instability in 9 cases, instability plus LOH in 2 cases, and only LOH in 2 cases. These highly frequent alterations in Microsatellites, including instability and LOH, suggesting that secondary events due possibly to loss of fidelity in replication and repair machinery may be significantly associated with CML evolution.
Marcelo De Bello Cioffi - One of the best experts on this subject based on the ideXlab platform.
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Comparative chromosomal mapping of Microsatellite Repeats reveals divergent patterns of accumulation in 12 Siluridae (Teleostei: Siluriformes) species.
Genetics and molecular biology, 2020Co-Authors: Sukhonthip Ditcharoen, Francisco De Menezes Cavalcante Sassi, Luiz Antonio Carlos Bertollo, Wagner Franco Molina, Thomas Liehr, Pasakorn Saenjundaeng, Alongklod Tanomtong, Weerayuth Supiwong, Chatmongkon Suwannapoom, Marcelo De Bello CioffiAbstract:The freshwater family Siluridae occurs in Eurasia and is especially speciose in South and Southeast Asia, representing an important aquaculture and fishery targets. However, despite the restricted cytogenetic data, a high diploid number variation (from 2n=40 to 92) characterizes this fish group. Considering the large genomic divergence among its species, silurid genomes have experienced an enormous diversification throughout their evolutionary history. Here, we aim to investigate the chromosomal distribution of several Microsatellite Repeats in 12 Siluridae species and infer about their possible roles in the karyotype evolution that occurred in this group. Our results indicate divergent patterns of Microsatellite distribution and accumulation among the analyzed species. Indeed, they are especially present in significant chromosome locations, such as the centromeric and telomeric regions, precisely the ones associated with several kinds of chromosomal rearrangements. Our data provide pieces of evidence that repetitive DNAs played a direct role in fostering the chromosomal differentiation and biodiversity in this fish family.
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Heterochromatin Distribution and Chromosomal Mapping of Microsatellite Repeats in the Genome of Frieseomelitta Stingless Bees (Hymenoptera: Apidae: Meliponini)
Florida Entomologist, 2018Co-Authors: Jádilla Mendes Dos Santos, Marcelo De Bello Cioffi, Débora Diniz, Tecavita Ananda Santos Rodrigues, Ana Maria WaldschmidtAbstract:Abstract The stingless bees of tribe Meliponini are efficient pollinators playing a key role in ecosystem services. Frieseomelitta Friese (Hymenoptera: Apidae: Meliponini) includes 16 Neotropical species, of which 6 are found in the state of Bahia, northeastern Brazil. In order to provide a refined cytotaxonomic analysis, we characterized the heterochromatin composition and variation among 6 Frieseomelitta species. All species shared a diploid number (2n) of 30 chromosomes. Frieseomelitta dispar Moure, Frieseomelitta francoi Moure, and Frieseomelitta meadewaldoi Cockerell (Hymenoptera: Apidae), presented GC-rich heterochromatic regions while Frieseomelitta sp.n., Frieseomelitta varia Lepelitier, and Frieseomelitta doederleini Friese (Hymenoptera: Apidae) were characterized by homogenous heterochromatin, without evidence of AT or GC-rich sites. The number and location of Microsatellite Repeats mapped by fluorescence in situ hybridization revealed interspecific variation. These data were useful to identify each species based on chromosomal markers, and represent important tools for clarifying the interspecific differentiation among Frieseomelitta species and for understanding the genome evolution in bees as a whole. Resumo As abelhas sem ferrao pertencentes a tribo Meliponini sao polinizadores eficientes e desempenham papel fundamental nos servicos ecossistemicos. Frieseomelitta Friese (Hymenoptera) possui 16 especies neotropicais das quais 6 se encontram no estado da Bahia, nordeste do Brasil. Caracterizamos a composicao e variacao da heterocromatina de 6 especies de Frieseomelitta com a finalidade de uma analise citotaxonomica mais refinada,. Todas as especies compartilharam um numero diploide (2n) de 30 cromossomos. Frieseomelitta dispar Moure, Frieseomelitta francoi Moure, e Frieseomelitta meadewaldoi Cockerell (Hymenoptera: Apidae), apresentaram regioes heterocromaticas ricas em GC, enquanto Frieseomelitta sp.n., Frieseomelitta varia Lepelitier, e Frieseomelitta doederleini Friese (Hymenoptera: Apidae) foram caracterizadas por heterocromatina mais homogenea, sem evidencia de locais ricos em AT ou GC. O numero e a localizacao das repeticoes de microssatelites mapeadas pela hibridacao in situ fluorescente revelaram variacao interespecifica. Estes dados foram uteis para identificar as especies de Frieseomelitta com base em marcadores cromossomicos sendo importantes para a diferenciacao interespecifica e para compreender a evolucao do genoma em abelhas como um todo. View this article in BioOne
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Chromosomal mapping of Microsatellite Repeats in the rock bream fish Oplegnathus fasciatus, with emphasis of their distribution in the neo-Y chromosome.
Molecular cytogenetics, 2013Co-Authors: Bao Lou, Luiz Antonio Carlos Bertollo, Marcelo De Bello CioffiAbstract:Despite the theoretical and experimental progress, our understanding on sex chromosome differentiation is still diagrammatic. The accumulation of repetitive DNA sequences is believed to occur in early stages of such differentiation. As fish species present a wide range of sex chromosome systems they are excellent models to examine the differentiation of these chromosomes. In the present study, the chromosomal distribution of 9 mono-, di- and tri-nucleotide Microsatellites were analyzed using fluorescence in situ hybrization (FISH) in rock bream fish (Oplegnathus fasciatus), which is characterized by an X1X2Y sex chromosome system. Generally, the males and females exhibited the same autosomal pattern of distribution for a specific Microsatellite probe. The male specific Y chromosome displays a specific amount of distinct Microsatellites Repeats along both arms. However, the accumulation of these repetitive sequences was not accompanied by a huge heterochromatinization process. The present data provide new insights into the chromosomal constitution of the multiple sex chromosomes and allow further investigations on the true role of the Microsatellite Repeats in the differentiation process of this sex system.
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the chromosomal distribution of Microsatellite Repeats in the genome of the wolf fish hoplias malabaricus focusing on the sex chromosomes
Cytogenetic and Genome Research, 2011Co-Authors: Marcelo De Bello Cioffi, Eduard Kejnovsky, L A C BertolloAbstract:Distribution of 12 mono-, di- and tri-nucleotide Microsatellites on the chromosomes of 2 karyomorphs with 2 distinct sex chromosome systems (a simple XX/XY – karyomorph B and a multiple X1X
Tariq Ezaz - One of the best experts on this subject based on the ideXlab platform.
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Amplification of Microsatellite repeat motifs is associated with the evolutionary differentiation and heterochromatinization of sex chromosomes in Sauropsida
Chromosoma, 2016Co-Authors: Kazumi Matsubara, Denis O’meally, Bhumika Azad, Arthur Georges, Stephen D. Sarre, Jennifer A. Marshall Graves, Yoichi Matsuda, Tariq EzazAbstract:The sex chromosomes in Sauropsida (reptiles and birds) have evolved independently many times. They show astonishing diversity in morphology ranging from cryptic to highly differentiated sex chromosomes with male (XX/XY) and female heterogamety (ZZ/ZW). Comparing such diverse sex chromosome systems thus provides unparalleled opportunities to capture evolution of morphologically differentiated sex chromosomes in action. Here, we describe chromosomal mapping of 18 Microsatellite repeat motifs in eight species of Sauropsida. More than two Microsatellite repeat motifs were amplified on the sex-specific chromosome, W or Y, in five species ( Bassiana duperreyi , Aprasia parapulchella , Notechis scutatus , Chelodina longicollis , and Gallus gallus ) of which the sex-specific chromosomes were heteromorphic and heterochromatic. Motifs (AAGG)n and (ATCC)n were amplified on the W chromosome of Pogona vitticeps and the Y chromosome of Emydura macquarii , respectively. By contrast, no motifs were amplified on the W chromosome of Christinus marmoratus , which is not much differentiated from the Z chromosome. Taken together with previously published studies, our results suggest that the amplification of Microsatellite Repeats is tightly associated with the differentiation and heterochromatinization of sex-specific chromosomes in sauropsids as well as in other taxa. Although some motifs were common between the sex-specific chromosomes of multiple species, no correlation was observed between this commonality and the species phylogeny. Furthermore, comparative analysis of sex chromosome homology and chromosomal distribution of Microsatellite Repeats between two closely related chelid turtles, C. longicollis and E. macquarii , identified different ancestry and differentiation history. These suggest multiple evolutions of sex chromosomes in the Sauropsida.