Search

PurposeA tertiary lymphoid structure (TLS) refers to an organized infiltration of immune cells that is linked to a positive prognosis and improved response to immunotherapy. However, methods that promote TLS formation are limited and challenging to implement in clinical settings. In this study, we aimed to promote the formation and maturation of TLSs in lung adenocarcinoma (LUAD) by combining low-dose radiotherapy (LDRT) with immunotherapy.MethodsTissue sections from 198 patients who had undergone surgery were examined. Risk factors for patient survival were assessed, and the relationship between TLSs and five-year survival was analyzed. The Kras-LSL-G12D spontaneous lung cancer mouse model was used to screen the optimal irradiation dose (0/1/2 Gy whole lung irradiation) for promoting TLS formation. LDRT combined with anti-PD-1 was used to promote the formation and maturation of TLSs.ResultsTLS+, TLSHigh, TLS+GC+ and CD8High within TLS+ were associated with a favorable prognosis. LDRT increased the formation of early TLSs in the Kras-LSL-G12D lung cancer mouse model. In addition, LDRT combined with anti-PD-1 treatment can significantly improve the maturity of TLSs in mouse LUAD, resulting in greater antitumor effects. This antitumor effect was strongly associated with the number of CD8+ T cells within the TLSs.ConclusionWe successfully applied LDRT combined with PD-1 inhibitor therapy for the first time, which increased both the quantity and maturity of TLSs in lung cancer. This approach achieved a promising antitumor effect.

Real-time assessment of therapeutic response in patients with advanced lung cancer presents a major challenge throughout the treatment process. Currently, computed tomography imaging is often used; however, it is radiation-based and hysteretic and is not suitable for repeated use as a real-time assessment. Blood biomarkers represent a novel solution for assessing therapeutic response in patients with advanced lung cancer. In the present study, the efficacy of a methylation marker [methylated prostaglandin E receptor 4 (mPTGER4)] and four protein markers [carcinoma antigen 125 (CA125), carcinoembryonic antigen (CEA), cytokeratin 19-fragments (cyfra21-1) and neuron-specific enolase (NSE)] were simultaneously evaluated to determine their potential in facilitating therapeutic response monitoring as well as their prognostic values in patients with stage IV lung cancer. The results indicated that, following treatment, the blood levels of methylated PTGER4 and NSE had significantly decreased, and mPRGER4, CA125, CEA and NSE exhibited a significant decrease in percentage level. Since mPTGER4 exhibited a higher rate of positive detection prior to therapy, and a greater response of sensitivity to therapy compared to the protein markers, it may represent an improved marker for the monitoring of therapeutic response. The efficacy of the markers in predicting the overall survival (OS) rate of patients with stage IV lung cancer was also assessed. Results from the follow-up of patients (up to 891 days) revealed that the blood levels of mPTGER4, CA125 and NSE before treatment were able to predict overall survival (OS) rate. Additionally, the percentage change in expression levels of CA125, CEA and NSE was also able to predict the OS rate. In conclusion, the present results indicate that mPTGER4 represents an improved biomarker for monitoring therapeutic efficacy compared with CA125, CEA, Cyfra21-1 and NSE. In predicting the long-term survival of patients with stage IV lung cancer; however, the pre-treatment levels of mPTGER4, CA125 and NSE and the percentage changes of CA125, CEA and NSE may be used as the markers. [ABSTRACT FROM AUTHOR]