The increased collagen deposition can ligate their corresponding surface receptors [e.g., the discoidin domain receptor (DDR) family of receptor tyrosine kinases and certain types of integrin (e.g., α1β1, α2β1, α10β1, and α11β1)] of cancer cells.8 DDR, composed of two members, DDR1 and DDR2, regulates downstream molecules (e.g., STAT3, STAT5),9 which eventually coordinates cell adhesion, migration, proliferation, and matrix remodeling.9 This evidence concerns the gene STAT3 and cancer.