A study of antibody conjugates for the treatment of inflammatory breast cancer.

Abstract

e15016 Background: Inflammatory breast cancer (inflammatory carcinoma) is a rare metastatic malignant tumor, it accounts for about 2% of all breast cancer cases. Despite its low incidence, inflammatory breast cancer is highly invasive, its five-year survival rate is less than 41%, making its prognosis the worst of all breast cancer subtypes, and effective drugs are urgently needed in clinical practice. Therefore, our study develops novel antibody conjugate drugs that can target overexpressed-ICAM-1 in inflammatory breast cancer cells as an original molecular target precisely. Methods: In this study, flow cytometry was used to perform precise and quantitative target screening of inflammatory breast cancer cell lines (SUM-149, KPL4), the endocytosis efficiency of ADC drugs was verified by flow cytometry efficiency analysis and single-photon confocal analysis, and the cytotoxicity of different drugs and cell lines was explored by CCK8 experiment. A nude mouse model of orthotopic xenograft inflammatory breast cancer was constructed, and the in vivo therapeutic effect of inflammatory breast cancer was observed by intravenous injection of two ICAM-1 antibody conjugates (ICAM-1-MMAE and ICAM-1-DXD), also the ADC drug structure with the best therapeutic effect for inflammatory breast cancer was screened. Results: ICAM-1 molecule in a variety of inflammatory breast cancer cell lines were highly over-expressed, and the antibody internalization rate was 51% at 4h, and after the peak the endocytosis efficiency slowed down into the plateau stage; ICAM1-MMAE and ICAM1-DXD are safer than first-line chemotherapy agents for breast cancer; The tumor volume was significantly reduced after administration into the orthotopic breast cancer xenograft model, which further verified the obvious effect of ADC drugs in vivo. Conclusions: Both ICAM-1-MMAE and ICAM-1-DXD have shown significant anti-inflammatory breast cancer effects in vitro and in vivo, and this study provides potential antibody conjugate drugs for targeted therapy of inflammatory breast cancer, which is expected to help improve the poor prognosis of inflammatory breast cancer.