PD‑L1/PD‑1 blockade in breast cancer: The immunotherapy era (Review)

Oncol Rep. 2021 Jan;45(1):5-12. doi: 10.3892/or.2020.7831. Epub 2020 Nov 3.

Abstract

Breast cancer is a common malignant tumor in women. Triple‑negative breast cancer (TNBC) is highly invasive with a high rate of metastasis and poor prognosis. Programmed death ligand 1 (PD‑L1) plays an important role in mediating the escape of tumor cells from immune surveillance. There have been significant advances in understanding the biology of TNBC. This review presents a detailed discourse on the available data on the expression of PD‑L1 in breast cancer and preliminary clinical outcome of PD‑L1/PD‑1 inhibitors in breast cancer patients. Early clinical trials involving PD‑L1/PD‑1 inhibitors have exhibited efficacy in tumor response and/or disease control in patients with refractory metastatic breast cancer, particularly TNBC. Furthermore, the mechanisms and factors that influence the immunoediting process are summarized and their functions in detail are analyzed.

Keywords: breast cancer; programmed cell death‑1; programmed death ligand 1; immunotherapy.

Publication types

  • Review

MeSH terms

  • B7-H1 Antigen / analysis
  • B7-H1 Antigen / antagonists & inhibitors*
  • B7-H1 Antigen / metabolism
  • Biomarkers, Tumor / analysis
  • Biomarkers, Tumor / antagonists & inhibitors*
  • Biomarkers, Tumor / metabolism
  • Breast / immunology
  • Breast / pathology
  • Breast / surgery
  • Chemotherapy, Adjuvant / methods
  • Disease-Free Survival
  • Female
  • Humans
  • Immune Checkpoint Inhibitors / pharmacology
  • Immune Checkpoint Inhibitors / therapeutic use*
  • Lymphocytes, Tumor-Infiltrating / drug effects
  • Lymphocytes, Tumor-Infiltrating / immunology
  • Mastectomy
  • Neoadjuvant Therapy / methods
  • Neoplasm Recurrence, Local / epidemiology*
  • Neoplasm Recurrence, Local / immunology
  • Neoplasm Recurrence, Local / prevention & control
  • Prognosis
  • Programmed Cell Death 1 Receptor / analysis
  • Programmed Cell Death 1 Receptor / antagonists & inhibitors*
  • Programmed Cell Death 1 Receptor / metabolism
  • Randomized Controlled Trials as Topic
  • Triple Negative Breast Neoplasms / immunology
  • Triple Negative Breast Neoplasms / pathology
  • Tumor Microenvironment / drug effects
  • Tumor Microenvironment / immunology

Substances

  • B7-H1 Antigen
  • Biomarkers, Tumor
  • CD274 protein, human
  • Immune Checkpoint Inhibitors
  • PDCD1 protein, human
  • Programmed Cell Death 1 Receptor