Original Article
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World J Gastroenterol. May 14, 2014; 20(18): 5474-5482
Published online May 14, 2014. doi: 10.3748/wjg.v20.i18.5474
Use of lectin microarray to differentiate gastric cancer from gastric ulcer
Wei-Li Huang, Yang-Guang Li, Yong-Chen Lv, Xiao-Hui Guan, Hui-Fan Ji, Bao-Rong Chi
Wei-Li Huang, Hui-Fan Ji, Bao-Rong Chi, Department of Hepatology, the First Clinic Hospital of Jilin University, Changchun 130021, Jilin Province, China
Wei-Li Huang, Xiao-Hui Guan, Department of Gastroenterology, Affiliated Hospital of Beihua University, Jilin 132001, Jilin Province, China
Yang-Guang Li, Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
Yong-Chen Lv, Department of General Surgery, the Central Hospital of Jilin City, Jilin 132001, Jilin Province, China
Author contributions: Huang WL performed all the experiments; Li YG did all the statistical analysis; Lv YC and Guan XH contributed on the animal preparation; Ji HF contributed on some of the histological experiments; Chi BR designed the experiments and analyzed the data.
Correspondence to: Bao-Rong Chi, MD, PhD, Professor, Department of Hepatology, the First Clinic Hospital of Jilin University, No. 71 Xinmin Dajie, Changchun 130021, Jilin Province, China. chibr@jlu.edu.cn
Telephone: +86-431-88782528 Fax: +86-431-85612468
Received: October 13, 2013
Revised: January 26, 2014
Accepted: March 6, 2014
Published online: May 14, 2014
Processing time: 212 Days and 14 Hours
Abstract

AIM: To investigate the feasibility of lectin microarray for differentiating gastric cancer from gastric ulcer.

METHODS: Twenty cases of human gastric cancer tissue and 20 cases of human gastric ulcer tissue were collected and processed. Protein was extracted from the frozen tissues and stored. The lectins were dissolved in buffer, and the sugar-binding specificities of lectins and the layout of the lectin microarray were summarized. The median of the effective data points for each lectin was globally normalized to the sum of medians of all effective data points for each lectin in one block. Formalin-fixed paraffin-embedded gastric cancer tissues and their corresponding gastric ulcer tissues were subjected to Ag retrieval. Biotinylated lectin was used as the primary antibody and HRP-streptavidin as the secondary antibody. The glycopatterns of glycoprotein in gastric cancer and gastric ulcer specimens were determined by lectin microarray, and then validated by lectin histochemistry. Data are presented as mean ± SD for the indicated number of independent experiments.

RESULTS: The glycosylation level of gastric cancer was significantly higher than that in ulcer. In gastric cancer, most of the lectin binders showed positive signals and the intensity of the signals was stronger, whereas the opposite was the case for ulcers. Significant differences in the pathological score of the two lectins were apparent between ulcer and gastric cancer tissues using the same lectin. For MPL and VVA, all types of gastric cancer detected showed stronger staining and a higher positive rate in comparison with ulcer, especially in the case of signet ring cell carcinoma and intra-mucosal carcinoma. GalNAc bound to MPL showed a significant increase. A statistically significant association between MPL and gastric cancer was observed. As with MPL, there were significant differences in VVA staining between gastric cancer and ulcer.

CONCLUSION: Lectin microarray can differentiate the different glycopatterns in gastric cancer and gastric ulcer, and the lectins MPL and VVA can be used as biomarkers.

Keywords: Gastric cancer; Gastric ulcer; Lectin microarray; Lectin histochemistry; Differentiate

Core tip: To assess the different glycopatterns in gastric ulcer and cancer by lectin microarray, which was then validated by lectin histochemistry. The results showed that the glycosylation level of gastric cancer was significantly higher than that in ulcer; the subsequent validation with two lectins (MPL and VVA) using lectin histochemistry showed higher positive rates and signal intensity in all types of gastric cancer detected, when compared with ulcer, which was consistent with the results of the lectin microarray, suggesting that GalNAc bound by the lectins MPL and VVA could be used to distinguish gastric cancer from ulcer.