Establishment and characterization of NCC-LMS2-C1-a novel patient-derived cancer cell line of leiomyosarcoma.

Leiomyosarcoma (LMS) is a rare and aggressive mesenchymal malignancy, derived from smooth muscle cells or precursor mesenchymal stem cells for this tissue type. LMS has highly complex and unstable karyotypes, and the clinical outcomes in patients with LMS remain dismal as evidenced by the 5-year-survival of 64%. Novel therapeutic approaches are required to improve its clinical outcomes. Patient-derived cancer cell lines are indispensable as a tool to study the molecular mechanisms underlying clinical behaviors of tumor cells such as resistance to treatments, metastasis, and recurrence. However, only a limited number of LMS cell lines are publicly available, probably because of the rarity of patients with LMS, and a paucity of cell lines hinders the research on LMS. This study aimed to develop a patient-derived LMS cell line. We successfully established a cell line from the primary tumor tissue of a 90-year-old female patient with pleomorphic LMS, which we named NCC-LMS2-C1. NCC-LMS2-C1 cells were maintained as a monolayer culture for over 29 passages spanning 10 months. NCC-LMS2-C1 cells exhibited continuous growth, the ability to form spheroid, and invasion capability. We screened 213 anti-cancer drugs to find those that have anti-proliferation effects on NCC-LMS2-C1 cells, and identified a histone deacetylase inhibitor, romidepsin. In conclusion, we have established a novel LMS cell line, NCC-LMS2-C1, which will be a useful resource to study the mechanisms of LMS progression and perform high-throughput screening for anti-cancer drug discovery.