2099

ESR1

ER|ESR|ESRA|Era|NR3A1;estrogen receptor 1;ESR1;estrogen receptor 1

ER-alpha|estradiol receptor|estrogen nuclear receptor alpha|estrogen receptor|estrogen receptor alpha 3*,4,5,6,7*/822 isoform|estrogen receptor alpha delta 3*,4,5,6,7*,8*/941 isoform|estrogen receptor alpha delta 3*,4,5,6,7*/819-2 isoform|estrogen recepto

6q25.1

protein-coding

Osteosarcoma (OS) is the eighth most common form of childhood and adolescence cancer. Approximately 10%-20% of patients present metastatic disease at diagnosis and the 5-year overall survival remains around 70% for nonmetastatic patients and around 30% for metastatic patients. Metastatic disease at diagnosis and the necrosis grade induced by preoperative treatment are the only well-established prognostic factors for osteosarcoma. The DNA aberrant methylation is a frequent epigenetic alteration in humans and has been described as a molecular marker in different tumor types. This study evaluated the DNA aberrant methylation status of 18 genes in 34 OS samples without previous chemotherapy treatment and in fournormal bone specimens and compared the methylation profile with clinicopathological characteristics of the patients. We were able to define a three-gene panel (AIM1, p14ARF, and ESR1) in which methylation was correlated with OS cases. The hypermethylation of p14ARF showed a significant association with the absence of metastases at diagnoses, while ESR1 hypermethylation was marginally associated with worse overall survival. This study demonstrated that aberrant promoter methylation is a common event in OS and provides evidence thatp14ARF and ESR1 hypermethylation could be useful as a prognostic indicator for this disease.