Irradiation Mediates IFNα and CXCL9 Expression in Non-Small Cell Lung Cancer to Stimulate CD8+ T Cells Activity and Migration toward Tumors

Abstract

Irradiation-broken DNA fragments increase type I interferon and chemokines secretion in tumor cells. Since radiotherapy may augment tumor immunotherapy, we hypothesize that the chemokines increased by irradiation could recruit CD8+ T cells to suppress tumor proliferation. This study intended to unveil the secreted factors activating and recruiting CD8+ T cells in non-small-cell lung cancer (NSCLC). EGFR-positive A549 was selected and treated by X-irradiation (IR) to identify the overexpression of chemokines associated to CD8+ T cell cytotoxicity and recruitment. A transwell assay with Alexa 488-labeled CD8+ T cells was used to evaluate CD8+ T cell motility in vitro. A nuclear imaging platform by In111-labeled nivolumab was used to track CD8+ T cells homing to tumors in vivo. The activation markers GZMB, PRF-1, and IFNγ, migration marker CD183 (CXCR3), and inhibitory marker CD274 (PD-1), were measured and compared in CD8+ T cells with A549 co-cultured, chemokines treated, and patients with late-stage lung cancer. We found that IR not only suppressed A549 proliferation but also induced IFNα and CXCL9 expression (p < 0.05). IFNα majorly increased IFNγ levels in CD8+ T cells (p < 0.05) and synergistically with CXCL9 enhanced CD8+ T cell migration in vitro (p < 0.05). We found that CXCR3 and PD-1 were down-regulated and up-regulated, respectively, in the peripheral blood CD8+ T cells in patients with lung cancer (n = 4 vs. healthy n = 3, both p < 0.05), which exhibited reduction of cell motility (p < 0.05). The in vivo nuclear imaging data indicated highly CD8+ T cells migrated to A549-induced tumors. In addition, we demonstrated that healthy PBMCs significantly suppressed the parallel tumor growth (p < 0.05) and the radioresistant tumor growth in the tumor xenograft mice (p < 0.05), but PBMCs from patients with lung cancer had lost the anti-tumor capacity. We demonstrated that IR induced IFNα and CXCL9 expression in A549 cells, leading to CD8+ T cell migration. This study unveiled a potential mechanism for radiotherapy to activate and recruit CD8+ T cells to suppress lung tumors.

Dysregulation of NK and CD8+T Cells by the Microbiota Promotes the Progression of Lung Cancer

“…This may partly explain the significant retardation of tumour progression in Kras-mutated mice with loss of microbiota. The CXCL9-CXCR3 axis involves recruiting immune cells into the tumour microenvironment in a variety of solid tumours, such as epithelial ovarian cancer, non-small-cell lung cancer, melanoma, breast cancer, and colon cancer [29][30][31][32][33][34][35]. In the current study, we found that the expressions of CXCL9 and CXCR3 mRNA increased significantly in the lungs of Abt-Kras mice compared to paired controls as tumour progressed, and this may be the main reason for the constant amount of NK cells and CD8 + T cells in their lung (Figure 4).…”

Janus Silica Nanoparticle-Based Tumor Microenvironment Modulator for Restoring Tumor Sensitivity to Programmed Cell Death Ligand 1 Immune Checkpoint Blockade Therapy

“…60 The IUIPC-mediated migration of CD8+ T cells and NK cells were analyzed by transwell migration assay (3.0 μm pore size, Coring Incorporated). 61 In Vivo Experiments. All animal experiments were performed strictly according to the guidelines approved by the Ethics Committee of Mengchao Hepatobiliary Hospital of Fujian Medical University.…”

The paradoxical role of radiation‐induced cGAS–STING signalling network in tumour immunity

“…A study of combined RT and the ATR inhibitor AZD6738 therapy showed that CXCL10 gene expression in tumour cells was remarkably elevated at the transcript level in response to type I IFNs [4]. Increased CXCL10 expression was also observed in irradiated lung cancer A549 cells during STING‐mediated cytosolic nucleic acid sensing process [59]. Meanwhile, cGAS and STING deficiencies prevent cDC1s from expressing CXCL10 [60].…”