Decorin overexpression in several culture models of cancer (colon, mammary, and squamous carcinoma) inhibited proliferation and promoted apoptosis [190,191,192,193], and decorin treatment of mammary cancer cells or an orthotopic mammary carcinoma model (either directly or via an adenoviral vector) reduced tumor growth by 70% and substantially curbed metastasis [193]. Here, DCN is linked to squamous cell carcinoma.