Establishment and characterization of NCC-EMC1-C1: a novel patient-derived cell line of extraskeletal myxoid chondrosarcoma.

Extraskeletal myxoid chondrosarcoma (EMC) is a rare soft tissue sarcoma characterized by a myxoid matrix and a distinctive lobulated architecture, composed of cords and clusters of uniform round-to-rhabdoid cells. At the molecular level, EMC is defined by specific gene fusions involving NR4A3, most frequently EWSR1::NR4A3. The responses to conventional chemotherapy are limited, and the prognosis for patients with advanced or metastatic disease remains poor. We successfully developed the NCC-EMC1-C1 cell line using surgically resected tumor tissue from a patient with EMC. NCC-EMC1-C1 cells exhibited constant proliferation in monolayer culture, spheroid formation in low-attachment plates, and migration. High-throughput screening of 221 anticancer drugs using NCC-EMC1-C1 identified three candidates, brigatinib, panobinostat, and romidepsin, that demonstrated low IC₅₀ values. These data indicated the utility of NCC-EMC1-C1 for the experiments based on screening. We conclude that NCC-EMC1-C1 is a valuable tool for preclinical and basic research on EMC.