title: ESR1 and PGR polymorphisms are associated with estrogen and progesterone receptor expression in breast tumors.
abstract: Hormone receptor-positive (HR+) breast cancers express the estrogen (ERα) and/or progesterone (PgR) receptors. Inherited single nucleotide polymorphisms (SNPs) in ESR1, the gene encoding ERα, have been reported to predict tamoxifen effectiveness. We hypothesized that these associations could be attributed to altered tumor gene/protein expression of ESR1/ERα and that SNPs in the PGR gene predict tumor PGR/PgR expression. Formalin-fixed paraffin-embedded breast cancer tumor specimens were analyzed for ESR1 and PGR gene transcript expression by the reverse transcription polymerase chain reaction based Oncotype DX assay and for ERα and PgR protein expression by immunohistochemistry (IHC) and an automated quantitative immunofluorescence assay (AQUA). Germline genotypes for SNPs in ESR1 (n = 41) and PGR (n = 8) were determined by allele-specific TaqMan assays. One SNP in ESR1 (rs9322336) was significantly associated with ESR1 gene transcript expression (P = 0.006) but not ERα protein expression (P > 0.05). A PGR SNP (rs518162) was associated with decreased PGR gene transcript expression (P = 0.003) and PgR protein expression measured by IHC (P = 0.016), but not AQUA (P = 0.054). There were modest, but statistically significant correlations between gene and protein expression for ESR1/ERα and PGR/PgR and for protein expression measured by IHC and AQUA (Pearson correlation = 0.32-0.64, all P < 0.001). Inherited ESR1 and PGR genotypes may affect tumor ESR1/ERα and PGR/PgR expression, respectively, which are moderately correlated. This work supports further research into germline predictors of tumor characteristics and treatment effectiveness, which may someday inform selection of hormonal treatments for patients with HR+ breast cancer.
authors.affiliation: Department of Clinical Pharmacy, University of Michigan College of Pharmacy, Ann Arbor, Michigan; DLHertz@med.umich.edu.
authors.forename: Daniel L
authors.identifier: 0000-0003-0501-1035
authors.initials: DL
authors.lastname: Hertz
authors.affiliation: Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan;
authors.forename: N Lynn
authors.initials: NL
authors.lastname: Henry
authors.affiliation: Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor, Michigan;
authors.forename: Kelley M
authors.initials: KM
authors.lastname: Kidwell
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan;
authors.forename: Dafydd
authors.initials: D
authors.lastname: Thomas
authors.affiliation: Genomic Health, Incorporated, Redwood City, California;
authors.forename: Audrey
authors.initials: A
authors.lastname: Goddard
authors.affiliation: Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana;
authors.forename: Faouzi
authors.initials: F
authors.lastname: Azzouz
authors.affiliation: Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor, Michigan;
authors.forename: Kelly
authors.initials: K
authors.lastname: Speth
authors.affiliation: Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana;
authors.forename: Lang
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, Michigan;
authors.forename: Mousumi
authors.initials: M
authors.lastname: Banerjee
authors.affiliation: Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan;
authors.forename: Jacklyn N
authors.initials: JN
authors.lastname: Thibert
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan;
authors.forename: Celina G
authors.initials: CG
authors.lastname: Kleer
authors.affiliation: Breast Cancer Program, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland; and.
authors.forename: Vered
authors.initials: V
authors.lastname: Stearns
authors.affiliation: Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan;
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Hayes
authors.affiliation: Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana;
authors.forename: Todd C
authors.initials: TC
authors.lastname: Skaar
authors.affiliation: Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan; Department of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: James M
authors.initials: JM
authors.lastname: Rae
mesh_terms: D000483:Alleles; D001943:Breast Neoplasms / Q000235:genetics*; D047628:Estrogen Receptor alpha / Q000235:genetics*; D005260:Female; D015870:Gene Expression / Q000235:genetics; D005786:Gene Expression Regulation / Q000235:genetics*; D005838:Genotype; D006801:Humans; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011446:Prospective Studies; D011980:Receptors, Progesterone / Q000235:genetics*
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D011980:Receptors, Progesterone
keywords: AQUA; RT-PCR; estrogen receptor; genotype; immunohistochemistry; progesterone receptor