Eribulin Regresses a Cisplatinum-resistant Rare-type Triple-negative Matrix-producing Breast Carcinoma Patient-derived Orthotopic Xenograft Mouse Model

Background/Aim: Matrix-producing breast carcinoma (MPBC) is a rare and usually aggressive triple-negative breast cancer (TNBC). In the present report, we determined the drug sensitivity for a triple-negative MPBC using a patient-derived orthotopic xenograft (PDOX) model. Materials and Methods: The PDOX model was established in the left 2nd mammary by surgical orthotopic implantation (SOI). MPBC PDOX models were randomized into 4 groups (6 mice per group) when the tumor volume became 80 mm(3): G1, control group; G2, cisplatinum group [intraperitoneal (i.p.) injection, weekly, for 2 weeks]; G3, paclitaxel group (i.p., weekly, for 2 weeks); G4, eribulin group [intravenous (i.v.) injection, weekly, for 2 weeks]. All mice were sacrificed on day 15. Tumor volume and body weight were measured one time per week. Results: The MPBC PDOX model was resistant to cisplatinum (p=0.800). Paclitaxel suppressed tumor growth compared to the control group (p=0.009). However, only eribulin regressed the tumor (p=0.001). Conclusion: Eribulin has clinical potential for triple-negative MPBC patients.