Inhibition of serine and arginine-rich splicing factor 3 induces epidermal differentiation and decreases cutaneous squamous cell carcinoma risk

Serine/Arginine-rich splicing factor 3 (SRSF3) is one of 12 SRSFs that regulate gene expression via alternative splicing. SRSF3 is upregulated in cutaneous squamous cell carcinoma (cSCC) and several squamous cancer cell lines in relation to normal keratinocytes. We suppressed SRSF3 with a specific inhibitor, SFI003, and observed an increase in epidermal differentiation. Our data suggests that in cSCC, SRSF3 overexpression suppresses cellular differentiation to enable cancer progression. In a clinical setting, patients taking known SRSF3 inhibitors digoxin and amiodarone exhibited higher cSCC-free survival compared to a propensity score-matched cohort treated with beta blockers. Thus, SRSF3 upregulation may be a novel therapeutic target in cSCC that can improve patient prognoses.