To further explore the relationship of miR-20a and FPN expression in lung cancer, a total of five NSCLC cell lines (H23, H838, H1299, H1650, and H1975) were analyzed for the expression of premature mRNA (pre-mRNA) of FPN to identify cell lines that show comparable levels of FPN transcription. This evidence concerns the gene SLC40A1 and lung carcinoma.