L Qhiu1, X Cong, L Ja. 1. Department of Immunology, Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing 100029, China.
Abstract
OBJECTIVE: To study the expression of keratin 19, 20 (K19, K20) in different tumor cell lines and tumor tissues and its clinical implication. METHODS: Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was employed to examine the specific expression of K19 and K20 mRNA in eleven tumor cell lines and 33 corresponding tumor tissue specimens. RESULTS: The expression of K19 mRNA was detected in 4 kinds of tumor cell lines and all tumor tissues examined, but the magnitude of expression differed, with a difference ranging from 1.7 to 10 folds for the same type of cancer. In some patients, the level of expression was as low as 12% of the positive control. K20 mRNA expression was negative for lung and esophageal tumor cell lines and the corresponding carcinoma specimens. In one of 6 bladder cancer specimens and in 4 of 5 colorectal cancer tissues, K20 expression was positive, at a level of 41%-77% of the positive control. There was no expression of K20 in bladder tumor cell line EJ1 and colorectal tumor cell line SW480. CONCLUSION: These results demonstrate that K19 and K20 may be used as a valuable marker for detecting circulating cancer cells, but the low level of expression in some cases of carcinoma would probably result in false negative results.
OBJECTIVE: To study the expression of keratin 19, 20 (K19, K20) in different tumor cell lines and tumor tissues and its clinical implication. METHODS: Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was employed to examine the specific expression of K19 and K20 mRNA in eleven tumor cell lines and 33 corresponding tumor tissue specimens. RESULTS: The expression of K19 mRNA was detected in 4 kinds of tumor cell lines and all tumor tissues examined, but the magnitude of expression differed, with a difference ranging from 1.7 to 10 folds for the same type of cancer. In some patients, the level of expression was as low as 12% of the positive control. K20 mRNA expression was negative for lung and esophageal tumor cell lines and the corresponding carcinoma specimens. In one of 6 bladder cancer specimens and in 4 of 5 colorectal cancer tissues, K20 expression was positive, at a level of 41%-77% of the positive control. There was no expression of K20 in bladder tumor cell line EJ1 and colorectal tumor cell line SW480. CONCLUSION: These results demonstrate that K19 and K20 may be used as a valuable marker for detecting circulating cancer cells, but the low level of expression in some cases of carcinoma would probably result in false negative results.
Authors: Robert D Loberg; Yaron Fridman; Brian A Pienta; Evan T Keller; Laurie K McCauley; Russell S Taichman; Kenneth J Pienta Journal: Neoplasia Date: 2004 Jul-Aug Impact factor: 5.715