TPD52 and oral cavity squamous cell carcinoma: Ummanni et al. [32] reported that TPD52 expression activates Akt/phosphoinositide-3 kinase (PI3K) signaling, and we recently [24] demonstrated that TPD54 is a negative regulator of Akt/PI3K signaling and decreases the migration and adhesion of oral squamous cell carcinoma cells.