Fig. 1.

Skeletal muscle fiber cross-sectional area (CSA) in all fibers and myosin heavy chain (MHC) I and II fibers (A), myonuclei content in MHC I and II fibers (B), myofilament fractional area (C), and MHC and actin protein content in tissue homogenates (D) in controls and breast cancer patients. Values are means ± SE, with individual data points shown with each bar. For A–C, multiple observations within each individual were averaged to provide a single data point for each volunteer. Representative immunohistochemical images used to measure CSA and myonuclei content for control and cancer patients are shown above A and B, respectively. Scale bars = 100 µm. Representative electron microscopy images used to measure myofilament fractional area (C) for controls and cancer patients are shown above C and D, respectively. Scale bars = 1 µm. AU, arbitrary units. *P ≤ 0.05; †P = 0.07.