Dual silencing of IGF-I receptor and EGF receptor in colorectal cancer cells is associated with decreased proliferation and enhanced apoptosis

Overexpression and/or activation of tyrosine kinase receptors are common features of colorectal cancer (CRC). Using the human CRC cell lines DLD-1 and Caco-2, we evaluated the role of the IGF-I receptor (IGF-IR) and EGF receptor (EGFR) in cellular functions of these cells. We used the small interfering RNA (siRNA) technology to specifically down-regulate IGF-IR and EGFR expression. Knockdown of IGF-IR and EGFR resulted in inhibition of cell proliferation of DLD-1 and Caco-2 cells. An increased rate of apoptosis was associated with siRNA-mediated silencing of IGF-IR and EGFR as assessed by activation of caspase-3…