摘要：Anti-programmed cell death-1 (PD-1) antibodies has been approved to treat HCC. Some PD-1 ligands (PD–L1 and PD–L2) negative tumors respond to treatment of anti-PD-1 antibodies, and this fact may be caused by the expression of PD-1 ligands on non-tumor cells. PD–L1 was recently found to be expressed on CD14 cells from cancer patients. We investigate PD-1 ligands expression on CD14 cells of patients with HCC and the role of CD14 cells in an antitumor response. In this study, 87 patients diagnosed with HCC were enrolled. CD14 cells from patients with HCC expressed PD–L1 (4.5–95.5%) and PD–L2 (0.2–95.0%). According to cut-off values, we classified patients as those either with PD–L1 PD–L2 CD14 cells or other types of CD14 cells. The overall survival of patients with PD–L1 PD–L2 CD14 cells was shorter than that of patients with other types of CD14 cells (p = 0.0023). PD–L1 PD–L2 CD14 cells produced IL-10 and CCL1, and showed little tumoricidal activity against HepG2 cells. The tumoricidal activity of CD8 cells from patients with PD–L1 PD–L2 CD14 cells were suppressed by co-cultivation with CD14 cells from the syngeneic patient. Furthermore, anti-PD-1 antibody restored their tumoricidal activity of CD8 cells. In conclusion, some patients with HCC have PD–L1 PD–L2 CD14 cells that suppress their antitumor response. These inhibitory functions of CD14 cells may be associated with a poor prognosis in these patients.
