Table 1.

EGFR mutant cell-line models of acquired resistance to erlotinib

Cell line	Primary EGFR mutation	Drug selection	Erlotinib IC50 (μM)	EGFR T790M	EGFR amp	MET amp	Other
PC-9	Exon19 deletion	N/a	0.01	No	Yes*	No	N/a
PC-9R	Exon19 deletion	Erlotinib	>5	Yes	Yes*	No	N/a
HCC827	Exon19 deletion		0.005	No	Yes†	No	N/a
HCC827R1	Exon19 deletion	Erlotinib	>5	Yes	Yes†	No	N/a
HCC827R2	Exon19 deletion	Erlotinib	>5	No	Yes†	Yes	N/a
HCC4006	Exon19 deletion	N/a	0.02	No	Yes	No	N/a
HCC4006R	Exon19 deletion	Erlotinib	>5	No	No	No	EMT
HCC4011	L858R	N/a	0.03	No	Yes	No	N/a
HCC4011R	L858R	Erlotinib	>5	No	No	Yes	N/a
11-18	L858R	N/a	0.1	No	No	No	N/a
11-18R	L858R	Erlotinib	>5	No	No	No	NRAS Q61K

Six resistant cell lines were established from five parental cell populations. PC-9R and HCC827R1 cells harbored EGFR T790M. HCC827R2 and HCC4011R cells displayed MET amplification (amp) and increased levels of MET protein (Figs. S1A and S2). HCC4006R cells showed features of EMT (Fig. S1A). 11-18R cells harbored an NRAS Q61K mutation. N/a, not applicable.

*PC-9R cells showed further EGFR amplification.

^†HCC827R1and HCC827R2 cells showed no further EGFR amplification.