RESUMEN
Multiple Endocrine Neoplasia 1 gene (MEN1), which is known to be a tumor suppressor gene in lung tissues, encodes a 610 amino acid protein menin. Previous research has proven that MEN1 deficiency promotes the malignant progression of lung cancer. However, the biological role of this gene in the immune microenvironment of lung cancer remains unclear. In this study, we found that programmed cell death-ligand 1 (PD-L1) is upregulated in lung-specific KrasG12D mutation-induced lung adenocarcinoma in mice, after Men1 deficiency. Simultaneously, CD8+ and CD3+ T cells are depleted, and their cytotoxic effects are suppressed. In vitro, PD-L1 is inhibited by the overexpression of menin. Mechanistically, we found that MEN1 inactivation promotes the deubiquitinating activity of COP9 signalosome subunit 5 (CSN5) and subsequently increases the level of PD-L1.
Asunto(s)
Antígeno B7-H1 , Neoplasias Pulmonares , Proteínas Proto-Oncogénicas , Escape del Tumor , Animales , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Ratones , Humanos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Escape del Tumor/genética , Complejo del Señalosoma COP9/genética , Complejo del Señalosoma COP9/metabolismo , Microambiente Tumoral/inmunología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/metabolismo , Línea Celular Tumoral , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Ubiquitinación , MutaciónRESUMEN
BACKGROUND AND PURPOSE: In recent years, there has been extensive research on the role of exercise as an adjunctive therapy for cancer. However, the potential mechanisms underlying the anti-tumor therapy of exercise in lung cancer remain to be fully elucidated. As such, our study aims to confirm whether exercise-induced elevation of epinephrine can accelerate CD8+ T cell recruitment through modulation of chemokines and thus ultimately inhibit tumor progression. METHOD: C57BL/6 mice were subcutaneously inoculated with Lewis lung cancer cells (LLCs) to establish a subcutaneous tumor model. The tumor mice were randomly divided into different groups to performed a moderate-intensity exercise program on a treadmill for 5 consecutive days a week, 45 min a day. The blood samples and tumor tissues were collected after exercise for IHC, RT-qPCR, ELISA and Western blot. In addition, another group of mice received daily epinephrine treatment for two weeks (0.05 mg/mL, 200 µL i.p.) (EPI, n = 8) to replicate the effects of exercise on tumors in vivo. Lewis lung cancer cells were treated with different concentrations of epinephrine (0, 5, 10, 20 µM) to detect the effect of epinephrine on chemokine levels via ELISA and RT-qPCR. RESULTS: This study reveals that both pre- and post-cancer exercise effectively impede the tumor progression. Exercise led to an increase in EPI levels and the infiltration of CD8+ T cell into the lung tumor. Exercise-induced elevation of EPI is involved in the regulation of Ccl5 and Cxcl10 levels further leading to enhanced CD8+ T cell infiltration and ultimately inhibiting tumor progression. CONCLUSION: Exercise training enhance the anti-tumor immunity of lung cancer individuals. These findings will provide valuable insights for the future application of exercise therapy in clinical practice.
Asunto(s)
Carcinoma Pulmonar de Lewis , Neoplasias Pulmonares , Animales , Ratones , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Ratones Endogámicos C57BL , Linfocitos T CD8-positivos , Quimiocinas , Carcinoma Pulmonar de Lewis/terapia , Carcinoma Pulmonar de Lewis/patología , Microambiente Tumoral , Línea Celular TumoralRESUMEN
The angiotensin II type 2 receptor (AT2R) is a well-established component of the renin-angiotensin system and is known to counteract classical activation of this system and protect against organ damage. Pharmacological activation of the AT2R has significant therapeutic benefits, including vasodilation, natriuresis, anti-inflammatory activity, and improved insulin sensitivity. However, the precise biological functions of the AT2R in maintaining homeostasis in liver tissue remain largely unexplored. In this study, we found that the AT2R facilitates liver repair and regeneration following acute injury by deactivating Hippo signaling and that interleukin-6 transcriptionally upregulates expression of the AT2R in hepatocytes through STAT3 acting as a transcription activator binding to promoter regions of the AT2R. Subsequently, elevated AT2R levels activate downstream signaling via heterotrimeric G protein Gα12/13-coupled signals to induce Yap activity, thereby contributing to repair and regeneration processes in the liver. Conversely, a deficiency in the AT2R attenuates regeneration of the liver while increasing susceptibility to acetaminophen-induced liver injury. Administration of an AT2R agonist significantly enhances the repair and regeneration capacity of injured liver tissue. Our findings suggest that the AT2R acts as an upstream regulator in the Hippo pathway and is a potential target in the treatment of liver damage.