Figure 3.

Schematic representation of cancer cachexia. A cachectic muscle is characterized by a decrease in muscle mass due to changes in metabolism but also by changes in the function of the SCs. The skeletal muscle shows a reduced number of infiltrating cells (lymphocytes and macrophages), although it is degenerated in places. The fast fibers (light pink) are most severely affected and show a high degree of denervation, while slow fibers are not affected (dark pink). The main change is a state of hyper-quiescence of the SCs, which leads to overexpression of PAX7 via the NF-κB and myostatin pathways.