IGF1R and breast cancer: IGF-1R signaling is known to play an important role in the resistance of cells to apoptosis and this anti-apoptotic effect is most strongly observed during anchorage-independent conditions (reviewed in [42] and in metastatic breast cancer cells [43,44] The survival of cells in suspension, or the ability to suppress anoikis, is a critical step in the progression of invasive cancer because metastatic cells must survive under anchorage-independent conditions as they move from the primary tumor to distant sites.