EGFR and non-small cell lung carcinoma: In tumor cells, gene amplification as well as activating somatic mutations of RTKs represented by an activating mutation of EGFR in NSCLC cells, is often observed and the growth and survival of these tumor cells sometimes become exclusively dependent on (or ‘addicted to’) the aberrant overexpression of the RTK protein expressed on the cell surface [11, 28–32].