Instead, we found that these models recapitulate the heterogeneity of Trop2 expression exhibited by most HNSCC human tumors (see Zhang et al.42 and Supplementary Fig. 1) and they also show low levels of ErbB3 expression by IHC (Supplementary Fig. 9). The gene discussed is TACSTD2; the disease is head and neck squamous cell carcinoma.