Consistency of gene amplification and its expression at protein level of human epidermal growth factor receptor 2 in gastric carcinoma
10.3760/cma.j.issn.0254-1432.2013.10.010
- VernacularTitle:胃癌组织人类表皮生长因子受体2基因扩增与蛋白表达的一致性
- Author:
Xinyan ZHANG
;
Juanjuan FU
;
Wenjing PU
;
Zhenzhu SUN
- Publication Type:Journal Article
- Keywords:
Stomach neoplasms;
Receptor,epidermal growth factor;
Immunohistochemistry;
In situ hybridization,fluorescence;
Gene amplification
- From:
Chinese Journal of Digestion
2013;33(10):680-683
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the consistency of gene amplification and its expression at protein level of human epidermal growth factor receptor 2 (HER2) in gastric carcinoma.Methods From 2010 to 2012,120 gastric cancer specimens of patients with gastric cancer were collected,of which 100 were surgical specimens and 20 were specimens from biopsy under gastroscope.The protein expression of HER2 in 120 specimens was detected by immunohistochemistry (IHC).According to the results of IHC,the positive parts of HER2 expression of IHC slices were developed into tissue microarrays for fluorescence in situ hybridization (FISH) to test the gene amplification of HER2.The different parts with different color intensity of focal (+ + +) (≤ 10％ tumor cell strongly staining) specimens detected by IHC detection were compared with the results of FISH.Kappa test was performed for statistical analysis.Results Among 120 gastric cancer specimens,the results of IHC indicated that 77 specimens were positive with different staining intensity including 16 strong positive (+++),six focal positive (+++),37 moderate positive (++) and 18 weak positive (+).The positive rate of HER2 protein expression detected by IHC was 18.3％ (22/120).The results of FISH showed 41 specimens were positive and the rate of gene amplification was 34.2％.Among which,21 were moderate positive (++) detected by IHC,15 were strong positive (+ + +) and five were focal positive (+ ++).The positive rate of HER2 was 35.0％ (42/120) with IHC and FISH combined detection.The consistent rate of IHC and FISH was 91.6 ％ (76/83).Kappa coefficient was 0.960 (P＜0.01).In five positive specimens detected by FISH and which were focal positive (+ + +) by IHC,the different parts with different color intensity were compared with the results of FISH and gene amplification was found in all specimens.Conclusion Tissue microarray technology is consistent with IHC in HER2 detection in gastric cancer specimens and could help to improve the detection rate.
