HER3 targeting with an antibody-drug conjugate bypasses resistance to anti-HER2 therapies.
1区 · 医学
作者: Lucía Gandullo-Sánchez ; Emily Capone ; Alberto Ocaña ; Stefano Iacobelli ; Gianluca Sala ; Atanasio Pandiella
Despite impressive clinical benefit obtained with anti-HER2-targeted therapies, in advances stages, especially in the metastatic setting, HER2-positive tumors remain incurable. Therefore, it is important to develop novel strategies to fight these tumors, especially when they become resistant to available therapies. We show here that the anti-HER3 antibody-drug conjugate EV20/MMAF exerted potent anti-tumoral properties against several models of primary resistance and secondary resistance to common anti-HER2 available therapies, including trastuzumab, lapatinib, neratinib, and trastuzumab-emtansine. HER3 was expressed in these HER2+ breast cancer cells and knockdown experiments demonstrated that HER3 expression was required for the action of EV20/MMAF. In mice injected with trastuzumab-resistant HER2+ cells, a single dose of EV20/MMAF caused complete and long-lasting tumor regression. Mechanistically, EV20/MMAF bound to cell surface HER3 and became internalized to the lysosomes. Treatment with EV20/MMAF caused cell cycle arrest in mitosis and promoted cell death through mitotic catastrophe. These findings encourage the clinical testing of EV20/MMAF for several indications in the HER2+ cancer clinic, including situations in which HER2+ tumors become refractory to approved anti-HER2 therapies.
2018-05-10·Journal of controlled release : official journal of the Controlled Release Society1区 · 医学
EV20-mediated delivery of cytotoxic auristatin MMAF exhibits potent therapeutic efficacy in cutaneous melanoma.
Cutaneous melanoma is one of the cancers with the fastest rising incidence and in its advanced metastatic form is a highly lethal disease. Despite the recent approval of several new drugs, the 5-year overall survival rate for advanced cutaneous melanoma is still below 20% and therefore, the development of novel treatments remains a primary need. Antibody-Drug Conjugates are an emerging novel class of anticancer agents, whose preclinical and clinical development has recently seen a remarkable increase in different tumors, including melanoma. Here, we have coupled the anti-HER-3 internalizing antibody EV20 to the cytotoxic drug monomethyl auristatin F (MMAF) to form a novel antibody-drug conjugate (EV20/MMAF). In a panel of human melanoma cell lines, this novel ADC shows a powerful, specific and target-dependent cell killing activity, independently of BRAF status. Efficacy studies demonstrated that a single administration of EV20/MMAF leads to a long-lasting tumor growth inhibition. Remarkably, the effect of this novel ADC was superior to the BRAF inhibitor vemurafenib in preventing kidney, liver and lung melanoma metastases. Overall, these results highlight EV20/MMAF as a novel ADC with promising therapeutic efficacy, warranting extensive pre-clinical evaluation in melanoma with high levels of HER-3 expression.