SOX9 and small cell lung carcinoma: Huang et al. first discovered cancers with tuft cell-like signatures (i.e., the expression of tuft cell markers, e.g., the master regulator POU2F3 [9], and GFI1B, TRPM5, SOX9, CHAT, and AVIL [10]) as a small subset of small cell lung cancer (SCLC).