Desmocollin-3 was the most specific marker for poorly differentiated squamous cell lung carcinoma (100%), followed by CK5/6 (98.3%), glypican-3 (94.8%), Sox2 (94.8%), S100A2 (81%), S100A7 (75.9%), thrombomodulin (72.4%), p63 (48.3%), and HMCK (36.8%). This evidence concerns the gene S100A7 and squamous cell lung carcinoma.