PD-L1	Programmed cell death ligand-1
PD-1	Programmed cell death protein-1
HNSCC	Head and neck squamous cell carcinoma
siRNA	Small interfering ribonucleic acid
EMT	Epithelial–mesenchymal transition
FDA	Food and Drug Administration
PD-L2	Programmed cell death ligand 2
IFN	Interferon
APC	Antigen-presenting cell
PCI	Pittsburgh Cancer Institute
NT	Nontargeting
KD	Knockdown
CV	Control vector
OE	Overexpression
RAC2	Gene encoding for the small Rho-GTPase Rac2
ARGHDIA	Gene encoding for Rho-GDP-dissociation inhibitor 1
PAK4	Gene encoding for serine/threonine-protein kinase PAK 4
ITGA4	Gene encoding for integrin alpha 4
MMP9	Gene encoding for matrix-metalloproteinase 9
RHO	Gene encoding for the small Rho-GTPase Rho
qPCR	Quantitative polymerase chain reaction
DMEM	Dulbecco’s modified Eagle’s medium
FCS	Fetal calf serum
EDTA	Ethylenediaminetetraacetic acid
DAB	3,3′-Diaminobenzidine
PBS	Phosphate buffered saline
PVDF	Polyvinylidene fluoride
SDS-PAGE	Sodium dodecyl sulfate polyacrylamide gel electrophoresis
γ	Gamma
SD	Standard deviation