Abstract A18: Predictive and prognostic significance of RECQ1 expression in breast cancer

RECQ1, also known as RECQL or RECQL1, is critical for DNA replication and repair. Germline mutations in the RECQ1 gene predispose to hereditary breast cancers. Overexpression of RECQ1 has been reported in a variety of human cancers including breast cancers. Our recent studies have identified a novel function of RECQ1 in regulation of gene expression and suggest that RECQ1 contributes to tumor development and progression, in part through regulating the expression of key genes that promote invasion and metastasis of cancer cells. Additionally, our data suggest that RECQ1 expression may serve as a predictive marker of clinical outcome. Preclinically RECQ1 depletion in breast cancer cells resulted in doxorubicin sensitivity, DNA double-strand breaks accumulation, S-phase cell cycle arrest, and apoptosis. Utilizing METABRIC cohort to investigate clinicopathologic significance of altered RECQ1 expression in sporadic breast cancers, we found that in ER-positive tumors that received endocrine therapy, low RECQ1 was associated with poor survival; in contrast, in ER-negative tumors that received adjuvant anthracycline-based chemotherapy, high RECQ1 was associated with poor disease-free survival. Taken together, our data provide the first preliminary evidence that RECQ1 is a promising prognostic and predictive biomarker in breast cancers. Citation Format: Swetha Parvathaneni, Xing Lu, Xiao Ling Li, Ritu Chaudhary, Ashish Lal, Srinivasan Madhusudan, Sudha Sharma. Predictive and prognostic significance of RECQ1 expression in breast cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr A18.