Dr. Tarn, Woan-Yuh 's publons link picture

Dr. Tarn, Woan-Yuh

Distinguished Research Fellow
  • 02-27899015 (Lab) (Room No: N223)
  • 02-26523052
  • 02-27829142 (Fax)



  1. mRNA splicing in neuron
  2. translational control in cancer
  3. long non-coding RNA

Education and Positions:
  • Ph.D. National Tsing Hua University
    Postdoc Assoc. Yale University

Highlight Detail

DDX3 regulates cancer immune surveillance via 3' UTR-mediated cell-surface expression of PD-L1

Dr. Tarn, Woan-Yuh
Cell Reports, Mar 13, 2024

Programmed death-1 (PD-1)/PD ligand-1 (PD-L1)-mediated immune escape contributes to cancer development and has been targeted as an anti-cancer strategy. Here, we show that inhibition of the RNA helicase DDX3 increased CD8+ T cell infiltration in syngeneic oral squamous cell carcinoma tumors. DDX3 knockdown compromised interferon-γ-induced PD-L1 expression and, in particular, reduced the level of cell-surface PD-L1. DDX3 promoted surface PD-L1 expression by recruiting the adaptor protein 2 (AP2) complex to the 3' UTR of PD-L1 mRNA. DDX3 depletion or 3' UTR truncation increased the binding of the coatomer protein complexes to PD-L1, leading to its intracellular accumulation. Therefore, this 3' UTR-dependent mechanism may counteract cellular negative effects on surface trafficking of PD-L1. Finally, pharmaceutic disruption of DDX3's interaction with AP2 reduced surface PD-L1 expression, supporting that the DDX3-AP2 pathway routes PD-L1 to the cell surface. Targeting DDX3 to modulate surface trafficking of immune checkpoint proteins may provide a potential strategy for cancer immunotherapy.