Detection of serum gastric cancer-associated MG7-Ag from gastric cancer patients using a sensitive and convenient ELISA method.
OBJECTIVE
To seek a high sensitive and convenient method for early diagnosis of gastric cancer by testing MG7-Ag in serum of gastric cancer patients and some other control groups using a convenient ELISA method.


METHODS
The expression of serum MG7-Ag was detected in 116 preoperative gastric cancer patients, 63 postoperative gastric cancer patients, 78 precancerous lesion patients, 50 healthy blood donors and patients of other cancers by a convenient ELISA method. For comparison, serum CEA, CA 50, CA 19-9 and TAG-72 were also detected in preoperative gastric cancer patients. Meanwhile, the expression of MG7-Ag was detected by immunohistochemical analysis in the groups of patients with gastric cancer or precancerous lesion mentioned above.


RESULTS
The positive rate of Mg7-Ag determined by ELISA was 83. 6% of preoperative gastric cancer patients, 54.8% of lung cancer patients, 45.5% of rectal cancer patients, 17.6% of colonic cancer patients, 14.2% of breast cancer patients, 47.6% of postoperative gastric cancer patients, 12.8% of precancerous lesions patients and 0% of healthy blood donors, respectively. The sensitivity of ELISA (83.6%) was found to be similar with that of immunohistochemistry (94%, p > 0. 01), while the false positive rate was lower (12.8% vs. 51.3%). MG7-Ag expression level in gastric cancer was correlated with tumor differentiation (p < 0. 01) and pathological stage (p < 0. 01).


CONCLUSIONS
This ELISA method may be a non-invasive candidate method for screening of large population with high risk of gastric cancer.
Jin
Bin
B
State Key Laboratory of Cancer Biology, Institute of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Shannxi, P.R. China.
Wang
Xin
X
Jin
Yan
Y
Xia
Wensen
W
Chen
Bei
B
Liu
Lin
L
Chen
Zheng
Z
Hong
Liu
L
Du
Wenqi
W
Yan
Kun
K
Wang
Honghong
H
Yuan
Donghong
D
Hui
Xiaoli
X
He
Li
L
Zhang
Faming
F
Zhao
Yunping
Y
Wu
Kaichun
K
Fan
Daiming
D
D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000097:blood*
D000951:Antigens, Neoplasm; C508753:MG7 antigen, human