β2-Adrenergic receptor modulates mitochondrial metabolism and disease progression in recurrent/metastatic HPV(+) HNSCC

a Western blot analysis of β2AR expression in MLM3 and mEERL cell lines (top), and relative expression data (bottom), confirming upregulation in the recurrent/metastatic MLM3 model, as compared with the parental mEERL model from which it spontaneously derived (columns represent mean fold change in β2AR protein expression [normalized to β-actin loading control]？±？SEM from n？=？4 independent biological replicates; p-value reflects results of Mann–Whitney test). b Unfixed, unpermeabilized immunostaining of β2AR (red) on mEERL (left) and MLM3 (middle) cells showing membrane localization of the receptor (secondary antibody-only staining is shown in the right panel). Nuclei were stained with DAPI (blue). Top: overlay; bottom: β2AR onl