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Avi Stein - One of the best experts on this subject based on the ideXlab platform.
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Telomerase activity and Cytokeratin 20 as markers for the detection and followup of transitional cell carcinoma: an unfulfilled promise.
The Journal of urology, 2001Co-Authors: A. Cassel, N. Lindenfeld, Yoel Mecz, Michal A. Rahat, Nitza Lahat, Avi SteinAbstract:Purpose: Telomerase activity compensates for the erosion of chromosomes and it has been detected in a wide variety of human tumors. Cytokeratin 20, an intermediate filament of epithelial cells, is expressed particularly in the urinary tract. These 2 molecules are candidates to become markers for the detection and followup of bladder carcinoma. We evaluate whether each molecule may serve as a potential marker and whether the 2 combined would improve the detection or followup of bladder carcinoma in a noninvasive manner.Materials and Methods: We obtained 44 morning urine samples from patients with transitional cell carcinoma patients and 26 from age matched patients with a wide variety of clinical disorders but no malignancy of any kind. A telomerase polymerase chain reaction-enzyme-linked immunosorbent assay kit was used to determine telomerase activity and Cytokeratin 20 expression was determined by nested reverse transcriptase-polymerase chain reaction.Results: All samples tested positive for Cytokeratin...
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Urinary Cytokeratin 20 as a marker for transitional cell carcinoma.
European urology, 2000Co-Authors: D. Rotem, A. Cassel, N. Lindenfeld, Yoel Mecz, Y. Sova, M. Resnick, Avi SteinAbstract:Objectives: To determine if detection of Cytokeratin 20 (CK20) gene expression, by reverse transcriptase–polymerase chain reaction (RT–PCR) in urine from transitional cell carcinoma
Masayuki Imamura - One of the best experts on this subject based on the ideXlab platform.
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Perioperative quantitative analysis of Cytokeratin 20 mRNA in peripheral venous blood of patients with colorectal adenocarcinoma.
Oncology reports, 2000Co-Authors: Naomi Funaki, Gakuji Ohshio, Junji Tanaka, Taketoshi Sugiyama, Atsushi Nonaka, Fumiaki Yotsumoto, M Furutani, Masayuki ImamuraAbstract:Hematogenous dissemination is a significant short-coming of colorectal carcinoma treatment. To screen patients with high risk for such blood-borne metastasis, we previously developed a highly sensitive system for the detection of Cytokeratin 20 (CK-20) mRNA in blood. For a more practical application, we improved this system by making it quantitative and capable of analyzing peripheral venous blood for the detection of perioperative changes in CK-20 mRNA. CK-20 mRNA was not always detected in the preoperative blood, even in patients in an advanced stage, but it was identified without fail in intra- and post-operative blood. In addition, more copies of CK-20 mRNA were observed in the intra-operative blood than in pre- and post-operative blood. This study suggests that analysis of perioperative changes may provide important information for the precise evaluation of hematogenous dissemination and of the effect of surgical maneuvers on recurrence.
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Cytokeratin 20 mRNA in peripheral venous blood of colorectal carcinoma patients
British journal of cancer, 1998Co-Authors: N. O. Funaki, J. Tanaka, Gakuji Ohshio, Hisashi Onodera, S. Maetani, Masayuki ImamuraAbstract:A highly sensitive system was previously developed by us to detect the presence of colorectal carcinoma cells in blood in the form of Cytokeratin 20 (CK20) mRNA. In the present study, we used an improved version of this system to analyse the peripheral blood of 28 patients with colorectal carcinoma, five patients with non-cancerous intestinal diseases and six normal controls for the presence or absence of CK20 mRNA and to investigate the relationship between the mRNA results and prognosis. All eight patients with recurrence were positive for CK20 mRNA, as were four patients in the Dukes' C stage with either distant metastasis or dissemination. Five of the nine patients in the Dukes' C stage with neither distant metastasis nor dissemination were positive, and three of these developed recurrence within 11 months after the analysis. Only one of the seven patients in the Dukes' A or B stage was positive, and none showed recurrence during the 1-19 months of observation. None of the five patients without carcinomas or of the six normal controls was positive. Although the follow-up period is limited and the recurrences were all local at present, these results suggest that the presence of CK20 mRNA in circulation may be a useful indicator for the screening of advanced colorectal carcinoma patients with a high risk of recurrence.
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Detection of colorectal carcinoma cells in circulating peripheral blood by reverse transcription-polymerase chain reaction targeting Cytokeratin-20 mRNA.
Life sciences, 1997Co-Authors: Naomi Funaki, Gakuji Ohshio, Hisashi Onodera, Junji Tanaka, Atsushi Itami, Takayuki Kasamatsu, Kazunobu Monden, Takashi Okino, Masayuki ImamuraAbstract:For the detection of circulating colorectal carcinoma cells, we investigated the presence of Cytokeratin 20 (CK 20) mRNA in the peripheral blood of colorectal carcinoma patients. Application of our published technique resulted in analysis by reverse transcription followed by three-step nested polymerase chain reaction. This analysis could detect a single Colo 205 colon cancer cell mixed with 1 ml of blood. Our system also successfully detected the presence of CK 20 mRNA in actual patients' peripheral blood samples. Our highly sensitive and specific system for the detection of CK-20 mRNA from patients' peripheral blood thus seems to be useful for screening for circulating colorectal carcinoma cells.
Yoshiki Sugimura - One of the best experts on this subject based on the ideXlab platform.
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REAL TIME REVERSE TRANSCRIPTASE POLYMERASE CHAIN REACTION OF URINARY Cytokeratin 20 DETECTS TRANSITIONAL CELL CARCINOMA CELLS
The Journal of urology, 2001Co-Authors: Takahiro Inoue, Hayao Nakanishi, Ken Ichi Inada, Hioki T, Masae Tatematsu, Yoshiki SugimuraAbstract:Purpose: We evaluate the diagnostic use of Cytokeratin 20 messenger (m) RNA quantitation in urine as a marker of urothelial transitional cell carcinoma using the real time reverse transcriptase polymerase chain reaction (RT-PCR).Materials and Methods: Spontaneously voided urine was obtained from 47 patients with urothelial transitional cell carcinoma (carcinoma group), 19 other urological diseases (noncarcinoma group) and 27 healthy volunteers (control group). Quantification of Cytokeratin 20 was performed with mRNA extracted from urine samples with primers and hybridization probes specific for Cytokeratin 20 on a LightCycler instrument (Roche Diagnostics Corp., Indianapolis, Indiana).Results: This method allowed reproducible quantitation of 10 to 106 Cytokeratin 20 expressing colon carcinoma cells per 107 peripheral blood leukocytes, comparable to the sensitivity of conventional RT-PCR with a wide linear measuring range. Cytokeratin 20 mRNA values in the carcinoma group (mean 35,850) were significantly h...
A. Cassel - One of the best experts on this subject based on the ideXlab platform.
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Telomerase activity and Cytokeratin 20 as markers for the detection and followup of transitional cell carcinoma: an unfulfilled promise.
The Journal of urology, 2001Co-Authors: A. Cassel, N. Lindenfeld, Yoel Mecz, Michal A. Rahat, Nitza Lahat, Avi SteinAbstract:Purpose: Telomerase activity compensates for the erosion of chromosomes and it has been detected in a wide variety of human tumors. Cytokeratin 20, an intermediate filament of epithelial cells, is expressed particularly in the urinary tract. These 2 molecules are candidates to become markers for the detection and followup of bladder carcinoma. We evaluate whether each molecule may serve as a potential marker and whether the 2 combined would improve the detection or followup of bladder carcinoma in a noninvasive manner.Materials and Methods: We obtained 44 morning urine samples from patients with transitional cell carcinoma patients and 26 from age matched patients with a wide variety of clinical disorders but no malignancy of any kind. A telomerase polymerase chain reaction-enzyme-linked immunosorbent assay kit was used to determine telomerase activity and Cytokeratin 20 expression was determined by nested reverse transcriptase-polymerase chain reaction.Results: All samples tested positive for Cytokeratin...
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Urinary Cytokeratin 20 as a marker for transitional cell carcinoma.
European urology, 2000Co-Authors: D. Rotem, A. Cassel, N. Lindenfeld, Yoel Mecz, Y. Sova, M. Resnick, Avi SteinAbstract:Objectives: To determine if detection of Cytokeratin 20 (CK20) gene expression, by reverse transcriptase–polymerase chain reaction (RT–PCR) in urine from transitional cell carcinoma
Karim Tabiti - One of the best experts on this subject based on the ideXlab platform.
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Urinary Cytokeratin 20 mRNA expression has the potential to predict recurrence in superficial transitional cell carcinoma of the bladder
Cancer Letters, 2006Co-Authors: Frank Christoph, Karim Tabiti, Steffen Weikert, Ingmar Wolff, Martin Schostak, Markus Müller, Kurt Miller, Mark SchraderAbstract:Abstract Higher levels of Cytokeratin 20 (CK 20) mRNA are expressed in malignant urothelial tissue compared to normal tissue. We determined the CK 20 mRNA expression in urine from patients with transitional cell carcinoma (TCC) of the bladder and assessed the biological behavior of such tumors in a 5-year follow-up. Second voided urine was preoperatively collected from 56 patients with bladder carcinoma, from 20 patients with nonmalignant urological diseases and from 40 healthy volunteers. RNA extraction from exfoliated urothelial cells was followed by quantitative real-time RT-PCR with the Light Cycler ® . Patients in the superficial TCC group had a median expression of 8226 AU (arbitrary units) with and 1523 AU without tumor recurrence ( P =0.023). No such correlation was detected in the group with muscle-invasive tumors. Kaplan–Meier analysis revealed a significant difference between recurrent and nonrecurrent disease ( P =0.019) in superficial but not in muscle-invasive TCC ( P =0.84). CK 20 mRNA expression in urine has the potential to identify patients at risk for recurrence of noninvasive papillary urothelial tumors. It helps to categorize patients prior to TUR-B, so that the cystoscopy interval during follow-up may be extended in those with low-risk superficial TCC.
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quantitative reverse transcription polymerase chain reaction detection of Cytokeratin 20 in noncolorectal lymph nodes
Clinical Cancer Research, 2001Co-Authors: Richie Soong, Kurt Beyser, Oliver Basten, Andreas Kalbe, Josef Rueschoff, Karim TabitiAbstract:Purpose: Unexpected reverse transcription-PCR detection of Cytokeratin 20 ( CK20 ) in samples from healthy individuals and cancer types not expected to express CK20 has cast uncertainty on the role of CK20 as a specific marker of disseminated colorectal cells. We aimed to clarify the specificity of CK20 by examining its expression profile by real-time reverse transcription-PCR. Experimental Design: A quantitative real-time PCR assay on the LightCycler instrument was developed and used to examine CK20 expression in tumors and lymph nodes from subjects with colorectal and breast carcinoma, head and neck and vulval squamous cell carcinoma, and melanoma. To select a method for reproducible quantification, four approaches were evaluated. Results: The developed assay allowed rapid, convenient-to-use, specific, sensitive, and reproducible CK20 quantification amenable to large-scale analysis. For quantity calculation, an efficiency-adjusted relative ratio method was selected that controls for RNA loading and integrity as well as inefficient PCR reactions and provides a platform for standardization across laboratories. Using this assay, we detected CK20 in 41 of 89 (46%) lymph nodes from noncolorectal cancer types. There was a strong association between CK20 detection and lymph node metastasis determined by histology ( P CK20 expression levels in colorectal cancer lymph nodes significantly exceeded the levels obtained in lymph nodes of extracolonic carcinomas ( P CK20 levels in lymph nodes and tumors from subjects with colorectal and breast cancers were similar in a tumor-type specific fashion. Conclusions: These results characterize low-level, epithelial cell-specific CK20 expression in infiltrated lymph nodes from subjects with noncolorectal cancer types and demonstrate the potential advantages of detecting circulating epithelial cells by quantitative PCR.
