A novel neoadjuvant therapy for early-stage non-small cell lung cancer in a mouse model

Background: Lung cancer is the common malignancy with high mortality rate in the world. Even with curative resection for early-stage lung cancer patients, the rate of postoperative recurrence and metastasis is still high. Neoadjuvant nivolumab combined with chemotherapy leads to improved pathological complete response rate and event-free survival in resectable non-small cell lung cancer (NSCLC) patients. However, the neoadjuvant therapy is not only accompanied by grade 3 or above adverse events which resulting in the potential missing out on the window for curative surgery for the patients, but also has low efficacy especially in patients with low programmed death ligand 1 (PD-L1) expression. Hence, it is particularly important to explore innovative ways to inhibit tumour recurrence and metastasis. Methods: In the present study, we investigated whether neoadjuvant therapy with intralesional Rose Bengal (RB) elicited specific immune responses compared with control group, and then the lung cancer mouse model was used to evaluated the immunological mechanism. Results: The secondary Lewis lung cancer cells (LLCs) tumour growth was significantly suppressed by RB intralesional injection into subcutaneous tumour; the formation rate of secondary tumours induced by the B16 melanoma cell injection was 100%. Intralesional RB neoadjuvant therapy before surgical resection exhibited effectively enhanced T central memory cells (Tcm) and T memory stem cells (Tscm) + na & iuml;ve T cells (Tn) infiltration, elicited stronger cytotoxic T lymphocyte (CTL) responses against LLCs, and displayed markedly higher proportions of splenic lymphocytes that produce tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) upon restimulation in a lung cancer mouse model. Conclusions: Based on our preclinical data, neoadjuvant therapy with intralesional RB injection generated immune memory and prevented the recurrence and metastasis of tumour in a lung cancer mouse model, which provides a new strategy for neoadjuvant treatment of early-stage NSCLC.