Investigation of the significance of alteration in gene promoter methylations for the cause of intratumoral heterogeneity of the expression levels of HER2.

2014 Fiscal Year Final Research Report

• Project/Area Number: 25860266
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Human pathology
• Research Institution: Kanazawa University
• Principal Investigator: OYAMA Takeru 金沢大学, 医学系, 助教 (00515314)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: CGH / gastric cancer / heterogeneity / HER2

Outline of Final Research Achievements

The tumors with intratumoral heterogeneity of HER2 protein were selected from the surgical specimens of HER2 positive advanced gastric cancer. Total RNA were isolated from both HER2 positive and HER2 negative area in a tumor. Whole genome comparative analyses using gene expression arrays of these RNA revealed that the expression levels of some gene including apoptosis associated genes were more than four times as high as those in the other area. The results of these gene expression levels were attempted to be validate by quantitative real-time RT-PCR, but failed to confirm the values of these gene expressions. This might be due to RNA degradation by aging of the tissues and/or formalin fixation. To acquire more reproducible data, Genome-Wide human SNP array analyses were performed on the genomic DNA from the two areas. These analyses revealed the difference in the gene copy number of some genes including a homeobox as were confirmed using fluolecence in situ hybridization.

Free Research Field

人体病理学