In a previous work, we were able to show that, in addition to homologous-directed repair (HDR) and non-homologous end joining (NHEJ), the mismatch-mediated repair (MMR) pathway with the main players EXO1, MSH3, and PCNA were clearly activated in chondrosarcoma cells after proton application [9]. This evidence concerns the gene MSH3 and chondrosarcoma.