Table 4.

CI for HNSCC cell lines after treatment with cetuximab for 168h with 1 µM MK2206 added during the last 72h of treatment.

Cell line	Condition	CI
SC263-S	1 µM MK2206 + 0.5 nM cetuximab	0.838
	1 µM MK2206 + 1 nM cetuximab	0.801
	1 µM MK2206 + 5 nM cetuximab	0.732
SCC22b-S	1 µM MK2206 + 0.5 nM cetuximab	0.705
	1 µM MK2206 + 1 nM cetuximab	0.688
	1 µM MK2206 + 5 nM cetuximab	0.578
SC263-R	1 µM MK2206 + 5 nM cetuximab	0.805
	1 µM MK2206 + 25 nM cetuximab	0.796
	1 µM MK2206 + 50 nM cetuximab	0.806
SCC22b-R	1 µM MK2206 + 5 nM cetuximab	0.867
	1 µM MK2206 + 25 nM cetuximab	0.865
	1 µM MK2206 + 50 nM cetuximab	0.818

CI < 0.800, CI = 1.000 ± 0.200, and CI > 1.200 indicate synergism, additivity or antagonism, respectively. CI < 0.800 are indicated in bold. Suffix -S: cetuximab sensitive cell line and suffix -R: acquired cetuximab resistant cell line.