DJM-1

Eribulin Induces Cell Cycle Arrest and Cell Death in cSCC Cell Lines

Advanced cutaneous squamous cell carcinoma (cSCC) often fails to respond well to chemotherapy and radiotherapy. No preclinical studies have evaluated eribulin's effectiveness against cSCC. Hsu et al. investigated eribulin's antitumor effects using cSCC cell lines and a novel patient-derived xenograft (PDX) model.

Given eribulin's anti-tubulin activity, they tested its IC₅₀ against two cSCC cell lines (A431 and DJM-1) and NHDFs (Fig. 1). After seeding, cells were treated with eribulin at various concentrations (0.001-10 nM) for 3 days. The IC₅₀ values were similar for A431 (0.20 nM) and DJM-1 (0.21 nM), but much higher for NHDFs (1.34 nM). cSCC cells were ~7 times more sensitive than NHDFs. Since cSCC cells were highly sensitive to eribulin in vitro, they used flow cytometry to analyze DNA content and cell cycle effects. At 24 h post-treatment, A431 and DJM-1 cells showed increased subgroups in G2/M and sub-G0/G1 phases, but decreased in G0/G1 phase. NHDFs were unaffected (Fig. 2). Additionally, A431 cells had increased early apoptosis, while DJM-1 cells had increased late apoptosis. This indicates that eribulin induces apoptosis in A431 cells and cell death in DJM-1 cells, consistent with previous reports.