- α-SMA, Col-I, and Col-III induced by TGF-β1 (qPCR and WB) were significantly repressed in the TGFβ1+ CM co-treatment group compared to TGF-β1 alone.- CM showed similar results in fibroblasts derived from keloid- After TGF-β1 stimulation of human dermal fibroblasts, CM significantly increased MMP-1, and TIMP-1 (qPCR and WB).- CM attenuated the TGF-β1-induced contraction of F-actin bundles and decreased the number of bundles.- CM addition to keloid fibroblasts also resulted in a reduction in supernatant collagen.- MMP-1, MMP-2, and TIMP1 were upregulated in keloid fibroblasts by CM. Here, TIMP1 is linked to keloid.