Cofilin1 palmitoylation restrains metastasis by enhancing Ser3 phosphorylation and reducing protein turnover

Abstract Cofilin1 is a regulator of actin dynamics, governing cellular protrusion, migration, and invasion. Although its activity is modulated by phosphorylation, the functional relevance of other post-translational modifications, particularly palmitoylation, has remained unexplored. Here, we show that Cofilin1 undergoes palmitoylation, which governs its stability and Ser3 phosphorylation. Elevated levels of palmitoylated Cofilin1 (palm-Cofilin1) correlate with reduced migratory and invasive capacity. We identify PPT1 and PPT2 as the depalmitoylating enzymes of Cofilin1, with DHHC1 and DHHC2 serving as its palmitoylating counterparts. To exploit this regulation, we developed a small-molecule inhibitor targeting PPT1/2. Treatment with this inhibitor increased palm-Cofilin1 levels and suppressed tumor cell migration and invasion both in vitro and in vivo. Collectively, these findings establish palmitoylation as a pivotal regulatory axis controlling Cofilin1 stability and activity, thereby linking post-translational crosstalk to actin cytoskeleton remodeling and tumor progression. Targeting the PPT1/2–Cofilin1 axis therefore represents a compelling therapeutic strategy against tumor metastasis.