BACKGROUND: Some tyrosine kinase receptors (RTKs) play critical roles in gastric cancer progression. Not only trastuzumab, but also several other agents targeting RTKs are being investigated for gastric cancer therapy. However, the simultaneous expression of multiple RTKs, which may interfere with the effectiveness of therapeutic agents, has not been evaluated in a large cohort with gastric adenocarcinoma (GAC). METHODS: We performed a tissue microarray analysis in 950 patients with GAC who underwent a gastrectomy without preoperative chemotherapy. The protein expressions of HER2, EGFR, MET and FGFR2 were evaluated using immunohistochemistry, and the gene amplifications of HER2, EGFR and MET were examined using dual-color in situ hybridization. RESULTS: The frequency of overexpression was 11.8% for HER2, 23.5% for EGFR, 24.9 % for MET and 31.1% for FGFR2. Whereas strong staining for each of the RTKs was heterogeneous, tumors with homogeneously strong staining areas often exhibited gene amplification. Strong EGFR expression was significantly associated with a poor outcome, but no prognostic correlations were observed in other RTKs. The overexpression of single and multiple RTKs was observed in 40.4 and 22.7% of the cases, respectively. HER2, EGFR, MET and FGFR2 predominance was observed in 10.1, 13.9, 16.1 and 22.9% of the GACs, respectively. CONCLUSIONS: Approximately two-thirds of patients with GAC exhibited the expression of at least one RTK and would be candidates for targeted therapies. Moreover, one-third of at least one RTK overexspressing cases showed multiple RTKs expression. Our results may be useful for selecting the most suitable patients for each targeted therapy.
BACKGROUND: Some tyrosine kinase receptors (RTKs) play critical roles in gastric cancer progression. Not only trastuzumab, but also several other agents targeting RTKs are being investigated for gastric cancer therapy. However, the simultaneous expression of multiple RTKs, which may interfere with the effectiveness of therapeutic agents, has not been evaluated in a large cohort with gastric adenocarcinoma (GAC). METHODS: We performed a tissue microarray analysis in 950 patients with GAC who underwent a gastrectomy without preoperative chemotherapy. The protein expressions of HER2, EGFR, MET and FGFR2 were evaluated using immunohistochemistry, and the gene amplifications of HER2, EGFR and MET were examined using dual-color in situ hybridization. RESULTS: The frequency of overexpression was 11.8% for HER2, 23.5% for EGFR, 24.9 % for MET and 31.1% for FGFR2. Whereas strong staining for each of the RTKs was heterogeneous, tumors with homogeneously strong staining areas often exhibited gene amplification. Strong EGFR expression was significantly associated with a poor outcome, but no prognostic correlations were observed in other RTKs. The overexpression of single and multiple RTKs was observed in 40.4 and 22.7% of the cases, respectively. HER2, EGFR, MET and FGFR2 predominance was observed in 10.1, 13.9, 16.1 and 22.9% of the GACs, respectively. CONCLUSIONS: Approximately two-thirds of patients with GAC exhibited the expression of at least one RTK and would be candidates for targeted therapies. Moreover, one-third of at least one RTK overexspressing cases showed multiple RTKs expression. Our results may be useful for selecting the most suitable patients for each targeted therapy.
Authors: Pamela L Kunz; Amirkaveh Mojtahed; George A Fisher; James M Ford; Daniel T Chang; Raymond R Balise; Charles D Bangs; Athena M Cherry; Reetesh K Pai Journal: Appl Immunohistochem Mol Morphol Date: 2012-01
Authors: Jochen K Lennerz; Eunice L Kwak; Allison Ackerman; Michael Michael; Stephen B Fox; Kristin Bergethon; Gregory Y Lauwers; James G Christensen; Keith D Wilner; Daniel A Haber; Ravi Salgia; Yung-Jue Bang; Jeffrey W Clark; Benjamin J Solomon; A John Iafrate Journal: J Clin Oncol Date: 2011-10-31 Impact factor: 44.544
Authors: Kab Choong Kim; Young Wha Koh; Heung-Moon Chang; Tae Hwan Kim; Jeong Hwan Yook; Byung Sik Kim; Se Jin Jang; Young Soo Park Journal: Ann Surg Oncol Date: 2011-04-06 Impact factor: 5.344
Authors: Guy Betts; Helen Valentine; Sue Pritchard; Richard Swindell; Victoria Williams; Shethah Morgan; Ewen A Griffiths; Ian Welch; Catharine West; Christopher Womack Journal: Virchows Arch Date: 2013-12-04 Impact factor: 4.064