Figure 3B demonstrates increased intensity of SMA staining and shows that the protein is now associated with cytoplasmic stress fibres. SMA upregulation was also observed when primary fibroblasts were cultured in conditioned medium from VB6, CA1 and 5PT cell lines squamous carcinoma cell lines (SCCM) (Figures 2A and 3C–H). This evidence concerns the gene SMN1 and squamous cell carcinoma.