Cell anchorage regulates apoptosis through the retinoblastoma tumor suppressor/E2F pathway
Epithelial cells are dependent upon adhesion to extracellular matrix for survival. We show
that loss of μ1 integrin receptor contact with extracellular matrix signals the inhibition of G 1
cyclin-dependent kinase activity. This loss of cyclin-dependent kinase activity leads to
accumulation of the hypophosphorylated (active) form of the retinoblastoma tumor
suppressor protein (Rb). We present evidence that in epithelial cells deprived of matrix
contact, the growth suppression signal elicited by hypophosphorylated Rb opposes …
that loss of μ1 integrin receptor contact with extracellular matrix signals the inhibition of G 1
cyclin-dependent kinase activity. This loss of cyclin-dependent kinase activity leads to
accumulation of the hypophosphorylated (active) form of the retinoblastoma tumor
suppressor protein (Rb). We present evidence that in epithelial cells deprived of matrix
contact, the growth suppression signal elicited by hypophosphorylated Rb opposes …
