Mmp-9 expression after metallic stent placement in patients with colorectal cancer: association with in-stent restenosis.
OBJECTIVE
To verify the expression of matrix metalloproteinase (MMP)-9 in stent-induced hyperplastic tissue from patients with colorectal cancer who received colorectal stents as a bridge to surgery.


METHODS
This prospective study was institutional review board-approved, and informed consent was obtained from all patients. Eleven patients (nine men, two women; mean age, 67 years; age range, 53-82 years) with malignant colorectal obstructions who received a colorectal stent between May and December 2010 were included. Tissue specimens were analyzed for MMP-9 and MMP-2 expression. After resection, the tissue was segmented into three parts: tumor tissue, stent-induced tissue hyperplasia, and normal colon tissue. MMP-9 and MMP-2 expression were determined by using zymography, Western blot analysis, and real-time reverse-transcription (qRT) polymerase chain reaction (PCR). Significance of differences between groups was evaluated with Friedman analysis of variance test. Signed-rank test was used to determine differences between malignant tumor tissue and stent-induced hyperplastic tissue groups.


RESULTS
Stent placement was technically successful in all 11 patients. Stent-induced hyperplastic tissues were found in all patients. Zymography (P = .003) and Western blot analysis (P = .008) showed that expression of MMP-9 was higher in malignant tumor tissue and stent-induced hyperplastic tissue groups compared with normal colorectal tissue group, demonstrating significant differences between groups but no significant differences between malignant tumor and stent-induced hyperplastic tissues. As for results of qRT PCR analysis, the stent-induced hyperplastic tissue group showed increases in messenger RNA expression level of MMP-9 compared with the malignant tumor tissue group (50.42-fold ± 66.30 higher).


CONCLUSIONS
High expression of MMP-9 is closely associated with stent-induced colorectal tissue hyperplasia in patients with colorectal cancer.
From the Medical Device Development Center, Osong Medical Innovation Foundation, Cheongwon-gun, Chungbuk, Korea (E.Y.K.); Departments of Radiology and Research Institute of Radiology (H.Y.S.), Surgery (J.C.K., Y.S.Y.), and Gastroenterology (B.D.Y.), University of Ulsan College of Medicine, Asan Medical Center, Asanbyeongwon-gil, 388-1 Pungnap-dong, Songpa-gu, Seoul 138-736, Korea; Department of Radiology, Kyung Hee University Hospital at Gangdong, School of Medicine, Kyung Hee University, Seoul, Republic of Korea (D.H.N.); and Department of Pathology, Asan Medical Center, Seoul, Korea (S.J.S.).
Eun-Young
EY
Kim
Ho-Young
HY
Song
Jin Cheon
JC
Kim
Yong Sik
YS
Yoon
Byong Duk
BD
Ye
Deok Ho
DH
Nam
Su-Jin
SJ
Shin
D000230:Adenocarcinoma / Q000150:complications* / Q000378:metabolism* / Q000473:pathology; D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D015179:Colorectal Neoplasms / Q000150:complications* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007415:Intestinal Obstruction / Q000209:etiology* / Q000473:pathology / Q000628:therapy*; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D008670:Metals; D008875:Middle Aged; D009367:Neoplasm Staging; D060888:Real-Time Polymerase Chain Reaction; D012008:Recurrence; D015607:Stents
D008670:Metals; D020780:Matrix Metalloproteinase 9