Subsequently, we used scRNA-seq to perform pairwise comparisons of tipifarnib-treated and untreated PDX tumors (Figs. 3a~f and 4; Additional file 2: Figure S4) to delineate the mechanisms of resistance originating from tumor-intrinsic and/or TME-mediated activation of salvage pathways other than HRAS. Here, HRAS is linked to neoplasm.