EGFR and colonic neoplasm: Since reports from our and other laboratories showed that HT reduces EGFR expression [3] and cetuximab down-regulates EGFR levels in colon cancer cells [14], we investigated whether HT and cetuximab per se and in combination, when used at low concentrations, would affect EGFR expression in HT-29 and WiDr cells (Figure 3).