HRAS and neoplasm: scRNA-seq of BC159-T#3 (Additional file 2: Figure S1 and S2) further confirmed the specific transcriptional upregulation of HRAS in tumor cells with basal squamous subtype marker expression, compared with low expression in non-malignant stromal and immune cells (Fig. 1g), indicating a strong dependence on HRASQ61R as a major truncal alteration driving tumor evolution in this advanced refractory case.