Abstract P4-10-28: Identification of a specific epigenetic signature in patients showing secondary hypertension upon anti-VEGF treatment from the GEICAM/2011-04 (BRECOL) study

Abstract

Abstract BACKGROUND The appearance of secondary hypertension (HTN) is one of the most common side effects of anti-angiogenic agents since it emerges in over 50% of the patients with these therapies. Independently of tumor type, in most clinical trials it was possible to observe a positive association between secondary HTN and better clinical outcome, including Progression Free Survival (PFS) and Overall Survival (OS). Preeclampsia is one of the biological models that better resembles the anti-VEGF/VEGFR action of these therapies. DNA methylation is one of the epigenetic mechanisms potentially related to variation in susceptibility to gestational HTN. The objective of our study is to define a specific epigenetic signature that could predict secondary HTN to anti-angiogenic treatment in patients that received bevacizumab in combination with chemotherapy (CT) from the BRECOL study. METHODS Patients (n=113) from BRECOL study (NCT01733628) received bevacizumab in combination with oxaliplatin or irinotecan + fluoropyrimidines for metastatic colorectal cancer (n=49), and with paclitaxel or capecitabine for metastatic breast cancer (n=64). Blood pressure (BP) was recorded with a Holter measurement (24 hours registration starting 2 hours after treatment administration). A methylation analysis was carried out on DNA obtained from pretreatment peripheral blood samples in 32 patients (28%) distributed in 4 experimental groups (8 patients / each) and classified according to their HTN history and to their BP variation upon bevacizumab plus CT: • Group A: patients with HTN history and with BP increase • Group B: patients with HTN history and with no BP increase • Group C: patients without HTN history and with BP increase • Group D: patients without HTN history and with no BP increase Analysis was realized with the “Infinium Human Methylation EPIC BeadChip” array (Illumina®) on bisulfite-converted DNA and differentially methylated sites were identified with the LIMMA (“Linear Models for Microarray Analysis”) bioinformatics tool (Bioconductor®). RESULTS Upon analysis of 850000 different methylation sites distributed all over the genome, we identified 27 (18 localized in the coding regions of the genes: FMNL2, METTL3, ACOT6, SCARNA20, PREX1, DNAI2, RAET1G, KCNJ8, GDF7, SYNPO2, CUGBP1, FRMD8, MKL2, HIF1A, TMEM177, UTP23, PXK and TNPO1; 9 localized in intergenic regions) that are differentially methylated in patients that showed secondary HTN to bevacizumab plus CT, independently of HTN history (Groups A + C vs. B + D). Based on Principal Components (PC) analysis, we defined a methylation score predictive of elevated BP. First PC (PC1) explains the 83.2% of the variability of the 27 identified methylation sites and allows to distinguish between patients that do and do not show secondary HTN. CONCLUSIONS High BP upon anti-angiogenic treatment is associated to specific DNA methylation profiles. We identified an epigenetic methylation signature putative predictive of secondary HTN to bevacizumab treatment in metastatic breast and colorectal cancer. Citation Format: Juan de la Haba, Teresa Morales-Ruiz, Pilar García-Alfonso, Jose Ponce Lorenzo, Lourdes Calvo, Antonio Antón, Raul Marquez, Pedro Sánchez-Rovira, Ana Santaballa, Eva Ciruelos, María Victoria García-Ortiz, Teresa Roldán-Arjona, Jesús Herranz, Massimo Chiesa, Rosalía Caballero, Javier Gallego, Álvaro Rodríguez-Lescure. Identification of a specific epigenetic signature in patients showing secondary hypertension upon anti-VEGF treatment from the GEICAM/2011-04 (BRECOL) study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-28.