title: ATR mutation in endometrioid endometrial cancer is associated with poor clinical outcomes.
abstract: PURPOSE Mutations in the DNA damage response gene ATR (exon 10 A10 mononucleotide repeat) have been previously described in endometrial and other cancers with defective DNA mismatch repair. In vitro studies showed that endometrial cancer cell lines with A10 repeat tract truncating mutations have a failure in the ATR-dependent DNA damage response. Cell lines carrying A10 mutations fail to trigger Chk1 activation in response to ionizing radiation and topoisomerase inhibitors. We sought to determine the frequency and clinicopathologic significance of ATR mutations in patients with endometrioid endometrial cancer. PATIENTS AND METHODS The ATR exon 10 A10 repeat was analyzed by direct sequencing in 141 tumors with microsatellite instability (MSI-positive) and 107 microsatellite stable (MSI-negative) tumors. The relationships between mutations and clinicopathologic variables, including overall and disease-free survival, were assessed using contingency table tests and Cox proportional hazard models. Results ATR mutations were identified in 12 cases (4.8%; three cases with insertions and nine cases with deletions). Mutations occurred exclusively in MSI-positive tumors (P = .02), with an overall mutation rate of 8.5%. Mutation was not associated with age, race, surgical stage, International Federation of Gynecology and Obstetrics grade, or adjuvant treatment. Multivariate analyses revealed a significant association with reduced overall survival (hazard ratio [HR] = 3.88; 95% CI, 1.64 to 9.18; P = .002) and disease-free survival (HR = 4.29; 95% CI, 1.48 to 12.45; P = .007). CONCLUSION Truncating ATR mutations in endometrial cancers are associated with biologic aggressiveness as evidenced by reduced disease-free and overall survival. Knowledge of ATR mutation status may hold promise for individualized treatment and targeted therapies in patients with endometrial cancer.
authors.affiliation: Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Washington University School of Medicine, 4911 Barnes Jewish Plaza, Box 8064, St Louis, MO 63110, USA. zighelboimi@wustl.edu
authors.forename: Israel
authors.initials: I
authors.lastname: Zighelboim
authors.forename: Amy P
authors.initials: AP
authors.lastname: Schmidt
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.forename: Premal H
authors.initials: PH
authors.lastname: Thaker
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Powell
authors.forename: Janet S
authors.initials: JS
authors.lastname: Rader
authors.forename: Randall K
authors.initials: RK
authors.lastname: Gibb
authors.forename: David G
authors.initials: DG
authors.lastname: Mutch
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Goodfellow
mesh_terms: D064007:Ataxia Telangiectasia Mutated Proteins; D001483:Base Sequence; D018269:Carcinoma, Endometrioid / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D018797:Cell Cycle Proteins / Q000235:genetics*; D018572:Disease-Free Survival; D016889:Endometrial Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D053842:Microsatellite Instability; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011379:Prognosis; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D016896:Treatment Outcome
chemical_list: D018797:Cell Cycle Proteins; C576597:ATR protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases