NK	Natural killer
HCC	Hepatocellular carcinoma
HRs	Hazard ratios
CI	Confidence interval
NKG2D	NK group 2 member D
NCRs	Natural cytotoxic receptors
IL	Interleukin
IFNR	Interferon receptor
TGF-βR	Tumor growth factor-β receptor
BAT3	HLA-B-associated transcript 3
BAG6	Bcl-2-associated athanogene 6
MLL5	Mixed lineage leukemia 5
PCNA	Proliferating cell nuclear antigen
B7-H6	B7 homolog 6
MIC	Major histocompatibility complex class I chain-related protein
ULBPs	UL16-binding proteins
KIRs	Killer immunoglobulin-like receptors
TIM-3	T cell immunoglobulin domain and mucin domain-3
TIGIT	T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain
PD-1	Programmed cell death-1
PD-L1	Programmed cell death ligand-1
LAG3	Lymphocyte activation gene-3
LAIRs	Leukocyte-associated immunoglobulin-like receptors
A2AR	Adenosine 2A receptor
ILTs	Immunoglobulin-like transcripts
HLA-E	Histocompatibility leucocyte antigen E
MHC-I	Major histocompatibility complex class I
PRISMA	Preferred Reporting Items for Systematic reviews and Meta-Analyses
OS	Overall survival
CSS	Cancer-specific survival
DFS	Disease-free survival
RFS	Recurrence-free survival
TTR	Time-to recurrence
PFS	Progression-free survival
NOS	Newcastle–Ottawa Scale
sMICA	Soluble MICA
ADCC	Antibody-dependent cell-mediated cytotoxicity
DCs	Dendritic cells
ILC1	Type 1 innate lymphoid cells