Chordoma is a locally aggressive, treatment- refractory tumour, that affects the spine and skull base. The tumour has very few mutations and low inflammatory cell infiltration and is considered a immunologically “cold” tumour. Findings from dedifferentiated chordoma, a rare variant in pediatric patients, suggest that disruption of the SWI/SNF complex, via the loss of SMARCB1 expression, might enhance the robustness of the antitumour immune response likely via enhanced antigen presentation. Emerging evidence of the respective role of PBRM1 and SMARCA4 in clear cell renal cell carcinoma and small cell carcinoma of the ovary (hypercalcemic type) have also highlighted these other members of the SWI/SNF complex in modulating anti-tumour immune response. This project explores and exploits this mechanism and to recapitulate it in adult chordoma, which does not typically carry these genetic defects, with specific epigenetic probes. The ultimate goal is to enhance the immune response to classical chordoma via selective modulation of the epigenome.