Research Paper Volume 11, Issue 15 pp 5848—5863

Sodium cantharidate targets STAT3 and abrogates EGFR inhibitor resistance in osteosarcoma

Figure 4. Combined treatment with sodium cantharidate and erlotinib decreases phosphorylation of STAT3 and EGFR. (A) MG63 and U2OS cells were treated with DMSO, SC, erlotinib, or a combination of SC and erlotinib for 24 h, and phospho-STAT3 and phospho-EGFR expression was evaluated by western blot. (B) Western blot analysis of phospho-STAT3, Bcl-2, and MMP2 expression in MG63 and U2OS cells treated with DMSO plus empty vector, SC alone, or a combination of SC and constitutively active STAT3 (STAT3-C) for 24 h. Sc, sodium cantharidate; Er, erlotinib. (C) MTT assay results from STAT3-C-transfected MG63 and U2OS cells. (D) Transwell migration assay results from MG63 and U2OS cells expressing STAT3-C.