Autophagy is induced in SCCHN cell lines by MK-2206 and SAR245408 and autophagy competence positively correlates with drug sensitivity.

<p><b>A</b>) Dose-response curve of SCCHN cell lines to MK-2206 and SAR245408. Cells were treated with the inhibitors for 72 hours and cell viability were assayed using Cell-Titer Blue reagent as described in Methods. <b>B</b>) SCCHN cell lines show variable autophagic activity defined by the ratio of LC3-II/LC3-I. The intensity of LC3-I and LC3-II bands were quantified with a Li-Cor imaging scanner. <b>C</b>) Western blots show PI3K/mTOR inhibitors induce autophagy in several SCCHN cell lines but not in SCC35 cells. <b>D</b>) Effect of MK-2206 and bafilomycin A1 on LC3-II protein in SCCHN cell lines. Cells were treated for 24 hours and bafilomycin A1 (final concentration 100 nM) was added 4 hours before harvesting. Western blotting was probed with LC3 antibody. LC3-II was quantified and normalized to tubulin. <b>E</b>) Drug sensitivity to MK-2206 and SAR245408 correlated with intrinsic autophagy competence.