EGFR and lung carcinoma: On the other hand, a differential expression of KCNQ channels has been observed in lung cancer, with higher expressions in side-populations than in main-population cells; moreover, when side-population cells were treated with the EGFR antagonist gefitinib [176] in combination with KCNQ blockers (TEA, 4-AP) or openers (flupirtine), the gefitinib resistance decreased [76].