miRNA profiling of primary lung and head and neck squamous cell carcinomas: Addressing a diagnostic dilemma

Abstract Objective To determine whether microRNA (miRNA) profiling of primary lung and head and neck squamous cell carcinomas could be useful to identify a specific miRNA signature that can be used to further discriminate between primary lung squamous carcinomas and metastatic lesions in patients with a history of head and neck squamous cell cancer. Methods Specimens of resected primary head and neck and lung squamous cell carcinomas were obtained from formalin-fixed, paraffin-embedded blocks. Paraffin blocks were sectioned and deparaffinized, and total RNA was isolated and profiled. Quantitative polymerase chain reaction was performed to verify array results. Results Twelve head and neck and 16 lung squamous cell carcinoma samples met quality control metrics and were included for analysis. Forty-eight miRNAs were differentially expressed ( P q Conclusions MicroRNA expression may be useful for discriminating between head and neck and lung squamous cell carcinomas, including miR-34a and the miR-10a:miR-10b ratio. This differentiation has clinical importance because it could help determine the appropriate therapeutic approach.