ACY1 and small cell lung carcinoma: We observed a similar general progressive decrease from T1 to T4 in the expression of aminoacylase-1 (Acy1; a cytosolic, homodimeric, zinc-binding enzyme that catalyzes the hydrolysis of acylated L-amino acids to L-amino acids and acyl groups), which is postulated to function in the catabolism and salvage of acylated amino acids, and its expression has been reported to be reduced or undetectable in small cell lung cancer cell lines and tumors [32].