The IFI30 expression, in melanoma (Goldstein et al, 2008) and squamous cell carcinoma (Wenzel et al, 2008), has been shown to enhance antigen presentation and to activate CTSB (Goldstein et al, 2008), which is required for osteoclast fusion during differentiation (McMichael et al, 2009). Here, CTSB is linked to squamous cell carcinoma.