Affiliation:
1. Department of Biology and Function in Head and Neck Yokohama City University Graduate School of Medicine Yokohama Japan
2. Department of Otorhinolaryngology‐Head and Neck Surgery Yokohama City University, School of Medicine Yokohama Japan
Abstract
AbstractBackgroundWe previously established a patient‐derived xenograft (PDX) model, patient‐derived organoids (PDOs), and PDX‐derived organoids (PDXOs) for salivary duct carcinoma (SDC). Using these models, this study examined the therapeutic effect of human epidermal growth factor receptor 2 (HER2) blockade on HER2‐positive SDC.MethodsThe therapeutic effect of lapatinib was assessed in SDC PDXOs with regards to cell growth, receptor/downstream signaling molecule expression, phosphorylation levels, and apoptosis. Effect of lapatinib treatment was evaluated in vivo in SDC PDX mice.ResultsThe siRNA knockdown of HER2 and lapatinib suppressed cell proliferation in SDC PDXOs. Lapatinib inhibited the phosphorylation of HER2 and its downstream targets, and induced apoptosis in SDC PDXOs. Lapatinib also significantly reduced tumor volumes compared with that of the control in SDC PDX mice.ConclusionFor the first time, we demonstrated the efficacy of anti‐HER2 therapy in HER2‐positive SDC using preclinical models of SDC PDX and PDXO.
Funder
Japan Society for the Promotion of Science