Many secreted factors are believed to inhibit cell proliferation in certain tissues such as tumors; however, the identity and action of most of these factors remains unknown. The recent identification of two autocrine ...

Dictyostelium cells secrete factors during growth and starvation. AprA (autocrine proliferation repressor), a 60 kDa protein secreted as part of a 150 kDa protein complex, functions as a cell proliferation repressor. In ...