Protein phosphatase Slingshot homolog 3 (SSH3) (SSH3)

Slingshot homolog 3 (SSH3) is a dual-specificity protein phosphatase that serves as a key regulator of actin cytoskeleton dynamics. Its primary biological function is the dephosphorylation and subsequent activation of cofilin, a protein essential for actin filament severing and turnover (UniProt P55805). By modulating cofilin activity, SSH3 controls cellular processes such as lamellipodia formation, cell migration, and chemotaxis (PubMed: 31434043). In clinical contexts, SSH3 is often identified as a pro-oncogenic factor; its overexpression is associated with increased invasive and metastatic potential in cancers like gastric and breast carcinoma (PubMed: 25605116). Although there are currently no FDA-approved drugs specifically targeting SSH3 mRNA or the SSH3 protein, it is an active area of research for RNA-based therapeutics. Experimental approaches using siRNA-mediated knockdown of SSH3 mRNA have demonstrated significant reductions in cancer cell motility, highlighting its potential as a therapeutic target (PubMed: 25605116). Targeting the mRNA directly via antisense oligonucleotides or RNA interference offers a strategy to downregulate the protein product in overexpressing tumors. However, therapeutic challenges include the potential for off-target effects on the actin cytoskeleton in healthy tissues, which is vital for normal cell function.

Other names

SSH-3LSlingshot-3Slingshot homolog 3Protein phosphatase Slingshot homolog 3

Knockdown of SSH3 mRNA or inhibition of the SSH3 protein prevents the dephosphorylation of cofilin, leading to an accumulation of inactive phospho-cofilin, which disrupts actin filament remodeling and inhibits cell migration (PubMed: 31434043).