[Clinical significant of semiquantificating DNA topoisomerase- I mRNA in colorectal cancer].
OBJECTIVE
To examine the clinical significance of determining the expression levels of DNA topoisomerase- I (topo-I) mRNA of colorectal cancer.


METHODS
The relative expression levels of topo-I mRNA in primary colorectal cancer and adjacent normal mucosa were semiquantificated by the RT-PCR method. The relative expression of thymidylate synthase (TS) mRNA of the primary lesions was also examined.


RESULTS
The topo- I mRNA expression was higher in the tumorous tissue than in the normal mucosa (n=22, p<0.01). The topo- I mRNA expression did not significantly correlate with 9 clinicopathological variables examined (n=22). In patients who received irinotecan hydrochloride (CPT-11) following the failure of 5-fluorouracil-based treatment, the topoI mRNA expression did not differ nor correlate with the response to CPT-11 (PR, n=14; SD, n=11; PR; n=24) (p=0.91). In these patients, there was no relationship between the topo I mRNA expression and the TS mRNA expression (p=0.22, r=0.18). In addition, the efficacy of CPT-11 did not correlate with combinations subdivided according to the expression levels of topo- I mRNA and TS mRNA.


CONCLUSIONS
Determination of topo- I mRNA levels of primary colorectal cancer may not be useful for predicting the efficacy of CPT-11 treatment alone or in combination with TS mRNA levels.
Ishida
Hideyuki
H
Dept. Digestive Tract and General Surgery.
Shirakawa
Kazuo
K
Ohsawa
Tomonori
T
Hayashi
Yoichi
Y
Okada
Norimichi
N
Nakada
Hiroshi
H
Yokoyama
Masaru
M
D000368:Aged; D000972:Antineoplastic Agents, Phytogenic / Q000627:therapeutic use; D002166:Camptothecin / Q000031:analogs & derivatives / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D004264:DNA Topoisomerases, Type I / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D000077146:Irinotecan; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013940:Thymidylate Synthase / Q000378:metabolism
D000972:Antineoplastic Agents, Phytogenic; D012333:RNA, Messenger; D000077146:Irinotecan; D013940:Thymidylate Synthase; D004264:DNA Topoisomerases, Type I; D002166:Camptothecin