. 2011 Oct 4;105(10):1554–1562. doi: 10.1038/bjc.2011.396

Table 2. IC₅₀ values for erlotinib, afatinib and gemcitabine in pancreatic cancer cell lines assessed by the SRB colorimetric assay and combination index (CI) values of gemcitabine plus afatinib or erlotinib in pancreatic cancer cell lines.

	IC₅₀ value
Cell line	Erlotinib	Afatinib	Gemcitabine	Afatinib+gemcitabine combination index (effect)	Erlotinib+gemcitabine combination index (effect)
BxPC-3	1.26 μM	11 nM	7.4 nM	0.31 (Synergism)	0.46 (Synergism)
AsPc-1	5.8 μM	367 nM	87.3 nM	0.62 (Synergism)	0.69 (Synergism)
FA6	>20 μM	1.37 μM	5.23 nM	0.85 (Slight synergism)	N/A
PANC-1	>20 μM	966 nM	21.4 nM	0.73 (Moderate synergism)	N/A
Capan-1	>20 μM	781 nM	104.9 nM	0.88 (Slight synergism)	0.66 (Synergism)
MiaPaCa-2	>20 μM	709 nM	6.4 nM	1.25 (Moderate antagonism)	1.30 (Moderate antagonism)
PT-45	>20 μM	1.02 μM	14.3 nM	1.40 (Moderate antagonism)	0.54 (Synergism)

Abbreviations: N/A=not available; IC₅₀=50% inhibitory concentration; SRB=Sulforhodamine B.

Interpretation of the results was based on the proposed descriptions for presenting the degrees of antagonism or synergism by Calcusyn software

Table 2. IC50 values for erlotinib, afatinib and gemcitabine in pancreatic cancer cell lines assessed by the SRB colorimetric assay and combination index (CI) values of gemcitabine plus afatinib or erlotinib in pancreatic cancer cell lines.