May be involved in cell adhesion and cell matrix association. May play a role in the regulation of anchorage versus migration or proliferation versus differentiation via its phosphorylation. May be a novel marker for leukemia diagnosis and for immature hematopoietic stem cell subsets. Belongs to the tetraspanin web involved in tumor progression and metastasis.
Subcellular locations: Cell membrane
Shedding may also lead to a soluble peptide.
Subcellular locations: Secreted
Highly expressed in mitotic cells with low expression during interphase. Detected at highest levels in skeletal muscle and colon with lower levels in kidney, small intestine, placenta and lung. Up-regulated in a number of human tumor cell lines, as well as in colorectal cancer, breast carcinoma and lung cancer. Also expressed in cells with phenotypes reminiscent of mesenchymal stem cells and neural stem cells.