Promotes cell adhesion and matrix assembly. Binds to various extracellular matrix proteins. Isoform 2: Cytoplasm. Isoform 2 is expressed in uterus, liver, lung, spleen, kidney, heart, bladder, skeletal muscle and brain (at protein level). Isoform 2 is expressed very low in mammary gland and intestine (at protein level). Isoform 2 is expressed in lactating mammary glands and mammary tumors (at protein level). Ubiquitous (isoform 1). Isoform 2 is expressed in ovary, uterus, mammary glands, liver, lung, spleen, kidney, heart, bladder, intestine, skeletal muscle and brain. Down-regulated by oncogenes (isoform 1). Isoform 2 is down-regulated by beta estradiol in mammary gland (at mRNA level). Isoform 2 is up-regulated by beta estradiol in mammary glands (at protein level). Up-regulated in lactating mammary glands and mammary tumors (at protein level). Phosphorylated. Belongs to the CCDC80 family.