Gastric Cancer
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Dec 21, 2005; 11(47): 7405-7412
Published online Dec 21, 2005. doi: 10.3748/wjg.v11.i47.7405
Gene expression profiling of gastric cancer by microarray combined with laser capture microdissection
Ming-Shiang Wu, Yi-Shing Lin, Yu-Ting Chang, Chia-Tung Shun, Ming-Tsan Lin, Jaw-Town Lin
Ming-Shiang Wu, Yu-Ting Chang, Jaw-Town Lin, Department of Internal Medicine and Primary Care Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan, China
Yi-Shing Lin, Genasia Biotechnology, Ltd., Taipei, Taiwan, China
Chia-Tung Shun, Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan, China
Ming-Tsan Lin, Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan, China
Author contributions: All authors contributed equally to the work.
Supported by National Science Council, NSC-91-3112-B002-007, Taipei, Taiwan, China
Correspondence to: Jaw-Town Lin, Department of Internal Medicine, National Taiwan University Hospital, No. 1, Chung-Shan S. Rd., Taipei, Taiwan, China. jawtown@ha.mc.ntu.edu.tw
Telephone: +886-2-23123456
Received: March 31, 2005
Revised: July 18, 2005
Accepted: July 20, 2005
Published online: December 21, 2005
Abstract

AIM: To examine the gene expression profile of gastric cancer (GC) by combination of laser capture microdissection (LCM) and microarray and to correlate the profiling with histological subtypes.

METHODS: Using LCM, pure cancer cells were procured from 45 cancerous tissues. After procurement of about 5 000 cells, total RNA was extracted and the quality of RNA was determined before further amplification and hybridization. One microgram of amplified RNA was converted to cDNA and hybridized to cDNA microarray.

RESULTS: Among 45 cases, only 21 were qualified for their RNAs. A total of 62 arrays were performed. These included 42 arrays for cancer (21 cases with dye-swab duplication) and 20 arrays for non-tumorous cells (10 cases with dye-swab duplication) with universal reference. Analyzed data showed 504 genes were differentially expressed and could distinguish cancerous and non-cancerous groups with more than 99% accuracy. Of the 504 genes, trefoil factors 1, 2, and 3 were in the list and their expression patterns were consistent with previous reports. Immunohistochemical staining of trefoil factor 1 was also consistent with the array data. Analyses of the tumor group with these 504 genes showed that there were 3 subgroups of GC that did not correspond to any current classification system, including Lauren’s classification.

CONCLUSION: By using LCM, linear amplification of RNA, and cDNA microarray, we have identified a panel of genes that have the power to discriminate between GC and non-cancer groups. The new molecular classification and the identified novel genes in gastric carcinogenesis deserve further investigations to elucidate their clinicopathological significance.

Keywords: Gastric cancer; Microarray; Laser capture microdissection