Table 1.

Cell lines employed in this study, sensitivities to gefitinib, and EGF-induced stimulation of EGFR, Akt, and ERK1/2

Cell LinesOriginIC50m)aFold Stimulation by EGFb
Colony Formation
PC9Human NSCLC (Adenocarcinoma)0.06 (1.0)4 (1.0)
A549Human NSCLC (Adenocarcinoma)13 (217)21 (5.3)3.511.115.6
H522Human NSCLC (Adenocarcinoma)13 (217)20 (5.0)
H322Human NSCLC (Adenocarcinoma)6.8 (113)27 (6.8)
H358Human NSCLC (Adenocarcinoma)2.0 (33)12 (3.0)
EBC-1Human NSCLC (Squamous cell carcinoma)NDc21 (5.3)
H157Human NSCLC (Squamous cell carcinoma)12 (200)30 (7.5)1254.12.3
QG56Human NSCLC (Squamous cell carcinoma)7.8 (130)42 (10.5)1.53.812.7
LK2Human NSCLC (Squamous cell carcinoma)8.0 (133)20 (5.0)ndd3.33.2
A431Human epidermoid carcinoma0.4 (1.0)10 (1.0)
KB3-1Human epidermoid carcinoma10 (25)15 (1.5)
  • a Drug sensitivity of nine human non-small lung cancer cell lines and two epidermoid cancer cell lines to gefitinib was assayed by both colony formation and MTS. IC50 value for each cell line is presented from two independent assays, and relative activity is presented in parentheses when normalized by IC50 for PC9 cells.

  • b The fold stimulation by EGF of EGFR, Akt, and ERK 1/2 is presented for each cell line when normalized by untreated control in the absence of EGF (see Fig. 4).

  • c ND: not determined because of poor colony-forming ability of the cell line.

  • d nd: not detected because of poor phosphorylation.