PUM3 and squamous cell carcinoma: We examined the expression of Puf-A protein in 82 NSCLC tumors, including 64 adenocarcinomas (ADCs), 14 squamous cell carcinomas (SCCs), 3 large cell carcinomas, and 1 sarcomatoid carcinoma, by immunohistochemistry (IHC) (Fig. 1A).