Figure 3. FIGURE 3: The p38β MAPK → C/EBPβ signaling pathway mediates autophagy activation by tumor in skeletal muscle cells.

(A) C/EBPβ activation in skeletal muscle of LLC tumor-bearing mice is dependent on p38β MAPK. Lysate of TA collected from p38β MAPK^f/f and p38β MAPK muscle-specific knockout mice on day 21 of LLC implant was analyzed by Western blotting for C/EBPβ activation (phosphorylation of Thr-188).

(B) C/EBPβ is critical to LCM-induced autophagy activation in myotubes. C2C12 myoblasts transfected with control or C/EBPβ-specific siRNA were treated with LCM or control medium for 8 h. C/EBPβ and LC3 were analyzed by Western blotting.

(C) Autophagy activation in skeletal muscle of LLC tumor-bearing mice is dependent on C/EBPβ. Lysate of TA collected from wild type and C/EBPβ knockout mice on day 21 of LLC implant was analyzed by Western blotting for LC3.