EGFR and squamous cell carcinoma: For example, in human epidermoid carcinoma HEp3 cells, α5 integrin binding to the epidermal growth factor receptor, EGFR, enhanced proliferation [10] while in Caco-2 and HT-29 colorectal carcinoma cells, α5/EGFR binding resulted in EGFR lysosomal degradation followed by proliferation arrest [6].