PAK1 and esophageal squamous cell carcinoma: Interestingly, upon exposure to MG132 (a specific proteasome inhibitor), the expression of PAK1 protein was drastically rescued compared with ivermectin alone treated groups in both tested cell lines of ESCC (Figure 5D), suggesting ivermectin‐triggered degradation of PAK1 is via the proteasome‐dependent signalling pathway in ESCC cells.