MAPK1 and cyst: Based on our previous results showing that mNGAL could inhibit the ERK and AKT pathways in 2L3 cells (Figure 4) and further decrease cell proliferation (Figure 3) and cyst enlargement (Figure 6), we used western blotting to analyze whether the ERK and AKT pathways were affected in pN + LS and pN − LS cells (Figure 8).