Abstract 1521: Quantitation of HER2 gene amplification using digital PCR

Abstract

Abstract Gene amplification is a common genetic abnormality in many types of cancers and has been implicated in playing important roles in cancer development. The most common types of amplified genes are oncogenes and drug-resistance genes. For example, Human epidermal growth factor receptor 2 (HER2) gene amplification, occurring in about 10-30% of breast cancer cases, is strongly associated with aggressive tumor progression and poor prognosis. HER2 also presents an effective therapeutic target, and several HER2 targeting agents have been approved for treatment of HER2 positive breast cancer by FDA. Analysis of HER2 gene amplification is important not only in selecting right patients for HER2 targeting agents but also monitoring the response to therapy and predicting clinical outcomes. Currently, fluorescence in situ hybridization (FISH) and immunohistochemical (IHC) analysis are standard testing approaches for HER2 gene amplification. However, the challenge for these methodologies is that HER2 gene amplification is less quantitative, especially with some samples whose HER2/CEP17 ratio fall into equivocal range, and the workflow is labor intensive. We have developed digital PCR (dPCR) technology on the QuantStudio™ 3D Digital PCR System and quantify gene copy numbers from zero to eight with high accuracy and precision. We analyzed FFPE samples for HER2 gene amplification and our data show that dPCR provides a robust and quantitative detection, simple workflow and a quick turn around time. This study demonstrate that dPCR quantitation of gene amplification could potentially be used to study any loci that are amplified in cancer. Citation Format: Kelly Li, Devin Do, Patricia Hegerich, Bruno Ping, David Keys, Nivedita Majumdar, Stephen Jackson, Francisco Cifuentes, Caifu Chen. Quantitation of HER2 gene amplification using digital PCR. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1521. doi:10.1158/1538-7445.AM2014-1521