Immunotherapies based on immune checkpoint blockade (ICB) have significantly improved patient outcomes and offered new approaches to cancer therapy over the past decade. To date, immune checkpoint inhibitors (ICIs) of CTLA-4 and PD-1/PD-L1 represent the main class of immunotherapy. Blockade of CTLA-4 and PD-1/PD-L1 has shown remarkable efficacy in several specific types of cancers, however, a large subset of refractory patients presents poor responsiveness to ICB therapy; and the underlying mechanism remains elusive. Recently, numerous studies have revealed that metabolic reprogramming of tumor cells restrains immune responses by remodeling the tumor microenvironment (TME) with various products of metabolism, and combination therapies involving metabolic inhibitors and ICIs provide new approaches to cancer therapy. Nevertheless, a systematic summary is lacking regarding the manner by which different targetable metabolic pathways regulate immune checkpoints to overcome ICI resistance. Here, we demonstrate the generalized mechanism of targeting cancer metabolism at three crucial immune checkpoints (CTLA-4, PD-1, and PD-L1) to influence ICB therapy and propose potential combined immunotherapeutic strategies co-targeting tumor metabolic pathways and immune checkpoints.
Humans ; Antibodies, Monoclonal/pharmacology* ; B7-H1 Antigen/antagonists & inhibitors* ; CTLA-4 Antigen/antagonists & inhibitors* ; Immune Checkpoint Inhibitors/pharmacology* ; Neoplasms/drug therapy* ; Programmed Cell Death 1 Receptor ; Tumor Microenvironment

OBJECTIVES: To investigate changes of pulmonary ventilation function and diffusion function in lung cancer patients after neoadjuvant immune checkpoint inhibitors (ICIs) therapy combined with chemotherapy treatment. METHODS: Patients with newly diagnosed lung cancer (Ⅱa-Ⅲb) admitted to Zhejiang Cancer Hospital from October 2021 to July 2022, who received ICIs combined with chemotherapy for more than two courses were enrolled. Patients underwent pulmonary ventilation function and diffusion function assessments before and after treatment. The demographic information, sizes and locations of cancer lesions, doses and duration of ICIs used, pulmonary function results before and after treatment, and the tumor regression were documented. The changes of pulmonary function parameters before and after the treatment were analyzed with paired t test and Wilcoxon rank-sum test. The factors influencing the pulmonary function changes were analyzed by multiple linear Lasso regression and ridge regression. RESULTS: Among the 52 patients, 50 cases were males (96.15%) and 43 cases were squamous carcinoma (82.69%). The medium age of the patients was 67 years. After neoadjuvant therapy, 36 patients (69.23%) showed remission of tumor lesions. After treatment, the parameters of pulmonary ventilation inspiratory vital capacity (IVC) and the area under the expiratory flow-volume curve (AREAex), and the parameter of pulmonary diffusion total lung capacity increased compared with the baseline (all P<0.05). Forced vital capacity (FVC) and forced expiratory volume in first second (FEV₁) also showed an increasing trend. Multivariate linear Lasso regression and ridge regression showed that baseline IVC had a significant negative effect on IVC improvement (Beta=－0.435, t=－2.968, P<0.01), baseline TLC had a significant negative effect on the improvement of TLC (Beta=－0.266, t=－2.474, P<0.05), and the remission of obstructive pneumonia favored the improvement of TLC (Beta=0.308, t=2.443, P<0.05). CONCLUSIONS After ICIs neoadjuvant treatment combined with chemotherapy, the lung ventilation and diffusion function can be improved in lung cancer patients, particularly for those with reduced baseline ventilation and diffusion function.
Male ; Humans ; Aged ; Female ; Lung Neoplasms/drug therapy* ; Neoadjuvant Therapy ; Immune Checkpoint Inhibitors/pharmacology* ; Lung ; Pulmonary Ventilation