Sarcomas are a family of tumors for which there are few targeted treatments and outcomes are poor once the cancer has metastasized. Many sarcomas harbor recurrent mutations in proteins, known as epigenetic regulators, that control which genes are expressed and when. Among the regulators most frequently impacted is ATRX, which condenses regions of DNA into tightly packaged chromatin that cannot be accessed for transcription, effectively “silencing” these genes. The effect of ATRX loss in sarcomas is poorly understood, however, and treatments that leverage ATRX deficiency are lacking. Using patient-derived sarcoma cell lines and tumor samples, Dr. Nacev aims to understand epigenetic dysregulation in ATRX-deficient sarcomas, to determine how this affects antitumor immunity, and to identify new therapeutic vulnerabilities.