Abstract 5542: Identification of Enolase1 as key drug target in breast cancer by the Berg Interrogative Biology™ platform.
Authors: Jing Enxuan , Hazarika Suwagmani , Sundararajan Pragalath , Fowler Samantha , Vishnudas Vivek K. , Sarangarajan Rangaprasad , Narain Niven R. 
Published: August 2014

Abstract
Breast cancer is characterized by subtypes of various expression of her2/neu, estrogen receptor (ER), and progesterone receptor (PR) markers. The metabolic drivers and correlation to glycolytic intermediates that contribute to breast tumor phenotypes are not fully understood. The Berg Interrogative Biology™ discovery platform was used to delineate distinct molecular signatures which reflect the oncogenic mechanistic chain of events. Human Enolase-I was identified as a critical node (hub) in the Berg cancer systems network output. Causal association of ENO1 and other proteins with diverse biological roles such as regulation of gene expression, genomic integrity, mRNA/microRNA processing, protein and ECM stability, and cytoskeleton organization provides a powerful snap shot of molecular events modulated by ENO1. As a key glycolytic enzyme, Enolase I has been implicated in tumor growth, cell death, and drug resistance. To further unravel the metabolic regulation by Eno1 in breast cancer, we generated lentivirus mediated stable human enolase I knockdown and overexpression breast cancer cell lines which were subjected to functional assays. The metabolic assessments using Seahorse XF96 analyzer revealed decreased glycolysis in Eno1 knockdown cells and increased glycolysis in Eno1 overexpressing breast cancer cells, confirming the functional perturbation induced by Eno1 protein levels. Bioenergetic profiling showed corresponding changes in OCR in both basal and uncoupled states in Eno1 overexpressing breast cancer cells, suggesting these cells underwent metabolic remodeling in response to Eno1 activity/levels. Proliferation assays using DNA quantification and cell viability revealed significant inhibition of cancer cell growth with Enolase I knockdown, while the Eno1 overexpression promoted proliferation of breast cancer cells normoxic/hypoxic conditions, congruent to expression changes of proliferation markers. Moreover, in response to perturbation of Eno1 mediated energy metabolism, various breast cancer cells displayed altered phosphorylation/activation of AMP-activated protein kinase, which mediated Eno1 induced proliferation change in different breast cancer cells. The approach in conjunction with multi-omic technologies and data integration using the Berg BNI (Bayesian
Network Inference) leverages the robust biological output of the networks with an agnostic, unbiased analytical tool to truly gain insight into the underlying pathophysiology of breast cancers. Ongoing efforts to overlay this novel insight into combination strategies with chemotherapy will advance the understanding to realize data-driven biomarker and therapeutic end-points. Taken together, the data suggest that Enolase
1 is a novel disease target breast cancer and serves as a fulcrum point in the metabolic governance of breast tumor development and progression.
Citation Format: Enxuan Jing, Suwagmani Hazarika, Pragalath Sundararajan, Samantha Fowler, Vivek K. Vishnudas, Rangaprasad Sarangarajan, Niven R. Narain. Identification of Enolase1 as key drug target in breast cancer by the Berg Interrogative Biology™ platform. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5542. doi:10.1158/1538-7445.AM2013-5542