Abstract 4929: An ARMS PCR assay for detection of PI3KCA mutations in FFPE tumor samples

Abstract

Abstract The activating mutations of phosphatidylinositol-3-kinase subunit pl10a (PIK3CA) occur in a variety of cancer types and serve as the predictive markers for response to inhibitors targeting a number of receptor tyrosine kinases (RTKs) and PI3K/AKT pathway. Therefore detection of PI3KCA mutations will guide patient selection for effective personalized cancer therapy. Here we reported a new method for the rapid and reliable detection of PI3KCA mutations by using modified mutation-specific ARMS primers. In this real-time PCR system, the mutant gene is selectively amplified by the modified ARMS primers and the amplicon extending signals are collected by the taqman-probe at the same time. The ARMS assay could detect 5 mutations on PI3KCA gene with a sensitivity of 0.5% under the background of a total of 10ng wild-type genomic DNA. By using this assay, we analyzed the PI3KCA mutations in 113 Chinese breast cancer FFPE samples in comparison with Sanger sequencing. Our results indicated that the positive rates were 27.4 %, while 24.8% when measured by Sanger sequencing. The coincidence rates of the two methods were 89.3 % for the positive samples and 96.5% for the negative samples. The total coincidence rate was 97.3%. In conclusion, our study provides a basis for the detection of somatic mutations in PI3KCA in a routine clinical setting. The ARMS PCR assay allows the detection of the PI3KCA mutations in FFPE samples with better sensitivity and feasibility than the current assays used in clinic. Note: This abstract was not presented at the meeting. Citation Format: Dehua Derek Yu. An ARMS PCR assay for detection of PI3KCA mutations in FFPE tumor samples. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4929. doi:10.1158/1538-7445.AM2015-4929