[Detection of interferon-induced transmembrane-1 gene expression for clinical diagnosis of colorectal cancer].
OBJECTIVE
To investigate the expression of the interferon-induced transmembrane-1 (IFITM1) gene in colorectal cancer (CRC) tissue and the serum anti-IFITM1 antibody responses of the patients and assess their value in clinical diagnosis of CRC.


METHODS
Semi-quantitative RT-PCR was performed to detect IFITM1 mRNA expression in the specimens of normal colonic mucosa, CRC tissue, inflammatory polyps, adenomatous polyps, gastric cancer, esophageal carcinoma and liver cancer tissues. Serum samples were collected from the patients to detect anti-IFITM1 antibody responses using Western blotting. The clinicopathological features of the carcinoma expressing IFITM1 gene were analyzed.


RESULTS
IFITM1 mRNA was expressed in 47.4 % (18/38) of the CRC specimens, a rate significantly higher than that in adenomatous polyps [15% (3/20)] and gastric cancer [4.8% (1/21)]; no obvious IFITM1 expression was found in normal colonic mucosa, inflammatory polyp, esophageal carcinoma or liver cancer tissues (P<0.001 or P<0.05). IFITM1 mRNA was strongly expressed in CRC at the expression level of 0.8048-/+0.2273, which was significantly higher than that in adenomatous polyps (0.4447-/+0.0989, P<0.001). No anti-IFITM1 antibody response was detected in healthy human sera, but in the CRC patients, the serum antibody response was detected at the rate of 36.8% (14/38), significantly higher than the rate of 9.5% (2/21) in gastric cancer (P<0.05). No antibody response was detected in esophageal carcinoma, liver cancer, inflammatory polyp or adenomatous polyps. Most of the IFITM1-expressing CRC had a diameter exceeding 5 cm, often invading the serous membrane with metastasis to the lymph nodes and the distant organs; these tumors were identified mostly as well-differentiated adenocarcinoma in Dukes stage C or D.


CONCLUSIONS
IFITM1 gene may play an important role in the pathogenesis, development and metastasis of CRC, and may serve as a potential biomarker for clinical diagnosis of CRC.
Liu
Yu-Hu
YH
Department of Digestive Diseases, Dongguan People's Hospital, Dongguan 523018, China. liuyuhu@126.com
Lin
Jua
J
Guo
Jian
J
You
Zhi-Jian
ZJ
Wang
Zai-Guo
ZG
Zhong
Dong
D
Yang
Xing-Long
XL
Zhang
Zhen-Shu
ZS
Xiao
Bing
B
Guo
Wen-Ying
WY
D000906:Antibodies / Q000097:blood; D000943:Antigens, Differentiation; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000235:genetics*; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000276:immunology / Q000378:metabolism
D000906:Antibodies; D000943:Antigens, Differentiation; D014408:Biomarkers, Tumor; D008565:Membrane Proteins; D012333:RNA, Messenger; C062010:leu-13 antigen