title: SERPINA1 is a direct estrogen receptor target gene and a predictor of survival in breast cancer patients.
abstract: Of all breast cancer patients, about 70% are ER+ and 10% are ER+/HER2+. The ER+/HER2+ patients have a worse outcome compared to ER+/HER2- patients. Currently there is a lack of effective prognosis biomarkers for the prediction of outcome in ER+/HER2+ patients. Genome-wide differences in ER binding between the endocrine-responsive and endocrine-resistant cells were discovered using ChIP-seq, and combined with gene expression microarray data to identify direct ER target genes. These genes were correlated to survival outcome using publicly available breast cancer patient cohorts. We found the expression of the gene SERPINA1 to have a significant predictive value for the overall survival (OS) of ER+ patients in the TCGA cohort, and validated this finding in the Curtis cohort. SERPINA1 also has a significant predictive value for the OS of ER+/HER2+ patients in the TCGA cohort, with validation in the Bild cohort. The expression of SERPINA1 can be suppressed by fulvestrant and HER2 siRNA. Our results indicate that ER is constitutively activated, resulting in an E2-independent ER binding to the SERPINA1 gene and upregulation of SERPINA1 expression. Importantly, results of survival correlation suggests that high expression of SERPINA1 could be predictive for a better clinical outcome of ER+ and ER+/HER2+ patients.
authors.affiliation: Department of Cancer Biology, Beckman Research Institute of the City of Hope, Duarte, California, USA.
authors.forename: Hei Jason
authors.initials: HJ
authors.lastname: Chan
authors.affiliation: Department of Molecular Medicine, Beckman Research Institute of the City of Hope, Duarte, California, USA.
authors.forename: Haiqing
authors.initials: H
authors.lastname: Li
authors.affiliation: Bioinformatics Core Facility, Beckman Research Institute of the City of Hope, Duarte, California, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Bioinformatics Core Facility, Beckman Research Institute of the City of Hope, Duarte, California, USA.
authors.forename: Yate-Ching
authors.initials: YC
authors.lastname: Yuan
authors.affiliation: Department of Medical Oncology, Beckman Research Institute of the City of Hope, Duarte, California, USA.
authors.forename: Joanne
authors.initials: J
authors.lastname: Mortimer
authors.affiliation: Department of Cancer Biology, Beckman Research Institute of the City of Hope, Duarte, California, USA.
authors.forename: Shiuan
authors.initials: S
authors.lastname: Chen
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology; D001665:Binding Sites; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D001943:Breast Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000401:mortality / Q000473:pathology / Q000628:therapy; D047369:Chromatin Immunoprecipitation; D019295:Computational Biology; D030541:Databases, Genetic; D004790:Enzyme Induction; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D065171:Estrogen Receptor Antagonists / Q000494:pharmacology; D005260:Female; D000077267:Fulvestrant; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D055106:Genome-Wide Association Study; D006801:Humans; D053208:Kaplan-Meier Estimate; D061986:MCF-7 Cells; D020411:Oligonucleotide Array Sequence Analysis; D011379:Prognosis; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D034622:RNA Interference; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D014162:Transfection; D000515:alpha 1-Antitrypsin / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D004958:Estradiol; D065171:Estrogen Receptor Antagonists; D000077267:Fulvestrant; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D000515:alpha 1-Antitrypsin; C043392:SERPINA1 protein, human; C508053:ERBB2 protein, human
keywords: SERPINA1; breast cancer; endocrine resistance; estrogen receptor; survival analysis