We then evaluated the expression of smooth muscle actin (α-SMA), and collagen deposition (Masson staining) in a subset of 43 metastasic primary tumours (22 stage IIIB and 21 stage IIIC) for which we had paraffin-embedded tissue, from the entire 80 samples series where we previously assessed PRL-3 mRNA expression [8]. The gene discussed is ACTA1; the disease is neoplasm.