Abstract
According to the latest Global Cancer Observatory (GLOBOCAN) 2022 estimates, lung cancer remains the second most commonly diagnosed cancer worldwide, with approximately 2.48 million new cases (11.4% of all cancer diagnoses) and over 1.86 million deaths (18.2% of all cancer-related deaths), making it the leading cause of cancer mortality globally. It has been reported that programmed death ligand 1 (PD-L1) is confirmed to interact with the tumor microenvironment (TME) to mediate the immune escape of lung cancer. PD-L1, which is highly expressed in lung cancer cells, activates the programmed death receptor 1 (PD-1)/PD-L1 signaling pathway by binding to PD-1, thereby inhibiting the function of lymphocytes and the release of cytokines, inducing activated lymphocyte apoptosis, resisting the killing effect of lymphocytes, ultimately leading to immune escape in lung cancer. PD-L1 inhibitors, a hot spot in tumor immunotherapy, can restore the activity of T cells, thereby enhancing the body's immune response, and ultimately enabling the immune system to effectively recognize and kill lung cancer cells, thereby enabling lung cancer patients to achieve long-term tumor remission. At present, a variety of PD-L1 inhibitors have been approved for application and have achieved good clinical efficacy in the treatment of lung cancer. This article reviews the research progress of the interaction between PD-L1 and the TME to mediate immune escape from lung cancer and the role of PD-L1 inhibitors in the treatment of lung cancer.