Matrix remodeling enzymes involved in osteogenesis are indeed expressed by chordomas [66], and ARF-8 cells expressed a variety of such enzymes, including cathepsins A, B, D, K, L, and X/P/Z (from proteomics, Supplemental Table S2) along with secreted cathepsins A, B, C, D, E, L, S, V, and X/Z/P (from arrays, Figure 5). The gene discussed is CTSA; the disease is chordoma.