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Background: Non-small-cell lung cancer (NSCLC) is the most common malignant lung tumor and is difficult to be eradicated due to its immunosuppressive microenvironment. Chlorin e6 (Ce6)-mediated photodynamic therapy (PDT) could improve immunogenicity while destroying malignant tumor cells. However, the clinic application of Ce6-mediated PDT is limited by Ce6's poor water solubility and insufficient accumulation in lung cancer. To address this issue, Ce6 was loaded onto functionalized iron oxide nanoparticles linked with glucose to improve the distribution of Ce6 in lung cancer. Materials and results: The results of transmission electron microscopy (TEM), UV–Vis spectrophotometry, dynamic light scattering and near-infrared (NIR) spectroscopy confirmed the successful preparation of the composites. Confocal and flow cytometry showed IO–PG–GLU–Ce6 significantly enhanced the uptake of Ce6 by lung cancer cells and produced more reactive oxygen species (ROS) under NIR light irradiation. In addition, the detection of cell viability, proliferation and apoptosis indicated IO–PG–GLU–Ce6 achieved stronger photo-toxicity to lung cancer cells. Moreover, IO–PG–GLU–Ce6 treatment effectively damaged the DNA of lung cancer cells and thereby activated STING, up-regulated the expression of IFN-β, HMGB1 and HSP90, indicating augmented immunogenicity of lung cancer cells. Further results of in vivo, organ imaging and tissue fluorescence sections demonstrated IO–PG–GLU–Ce6 significantly improved the distribution of Ce6 in tumor tissues of lung cancer-bearing mice as well. Finally, the findings of in vivo study and immunohistochemistry confirmed the better efficacy of IO–PG–GLU–Ce6. HE staining results of vital organs suggested that the composites were less toxic. Conclusion: In conclusion, Ce6 loaded by functionalized iron oxide nanoparticles linked with glucose exhibited both target photodynamic efficacy and the ability to enhance its immunogenicity in lung cancer. This study provides a promising strategy for augment of the targeting delivery of Ce6 and its mediated photodynamic and immunotherapy. [ABSTRACT FROM AUTHOR]

Introduction: Poliovirus receptor (PVR) is a tumor promoter and a regulatory checkpoint that enhances immunosuppression. We investigated PVR expression by applying immunohistochemistry (IHC) staining. A positive association existed between PVR expression and cytotoxic T lymphocyte-associated antigen 4 (CTLA4) expression in patients with surgically resected non-small-cell lung cancer (NSCLC). PVR expression is a prognosis predictor of lung adenocarcinoma. Purpose: To investigate the prognostic significance of PVR expression and CTLA4 expression for surgically resected NSCLC. Patients and methods: The medical records of 108 Chinese patients with primary NSCLC who underwent surgery were retrospectively reviewed. The expression of PVR and CTLA4 were measured through IHC. Clinical characteristics, the association between PVR and CTLA4, and the prognostic significance of PVR were analyzed. Results: A significant positive association was observed between PVR and CTLA4 expression in NSCLC (P = 0.016). PVR had a high positive rate among females, nonsmokers, and patients with adenocarcinoma and advanced lung cancer. The overall survival (OS) of patients with negative PVR expression was significantly longer than that of patients with positive PVR expression (P = 0.049), especially among females (P = 0.03) and nonsmokers (P = 0.025). Multivariate analysis results showed that advanced tumor stage and PVR expression were independent prognosis predictors of poor OS. Conclusion: PVR can potentially serve as a prognostic predictor and biomarker for NSCLC and cancer anti-CTLA4 immunotherapy response. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence showed that regulating tumor microenvironment plays a vital role in improving antitumor efficiency. Programmed Death Ligand 1 (PD-L1) is expressed in many cancer cell types, while its binding partner Programmed Death 1 (PD1) is expressed in activated T cells and antigen-presenting cells. Whereas, its dysregulation in the microenvironment is poorly understood. In the present study, we confirmed that evodiamine downregulates MUC1-C, resulting in modulating PD-L1 expression in non-small cell lung cancer (NSCLC). Methods: Cell viability was measured by MTT assays. Apoptosis, cell cycle and surface PD-L1 expression on NSCLC cells were analyzed by flow cytometry. The expression of MUC1-C and PD-L1 mRNA was measured by real time RT-PCR methods. Protein expression was examined in evodiamine-treated NSCLC cells using immunoblotting or immunofluorescence assays. The effects of evodiamine treatment on NSCLC sensitivity towards T cells were investigated using human peripheral blood mononuclear cells and Jurkat, apoptosis and IL-2 secretion assays. Female H1975 xenograft nude mice were used to assess the effect of evodiamine on tumorigenesis in vivo. Lewis lung carcinoma model was used to investigate the therapeutic effects of combination evodiamine and anti-PD-1 treatment. Results: We showed that evodiamine significantly inhibited growth, induced apoptosis and cell cycle arrest at G2 phase of NSCLC cells. Evodiamine suppressed IFN-γ-induced PD-L1 expression in H1975 and H1650. MUC1-C mRNA and protein expression were decreased by evodiamine in NSCLC cells as well. Evodiamine could downregulate the PD-L1 expression and diminish the apoptosis of T cells. It inhibited MUC1-C expression and potentiated CD8+ T cell effector function. Meanwhile, evodiamine showed good anti-tumor activity in H1975 tumor xenograft, which reduced tumor size. Evodiamine exhibited anti-tumor activity by elevation of CD8+ T cells in vivo in Lewis lung carcinoma model. Combination evodiamine and anti-PD-1 mAb treatment enhanced tumor growth control and survival of mice. Conclusions: Evodiamine can suppress NSCLC by elevating of CD8+ T cells and downregulating of the MUC1-C/PD-L1 axis. Our findings uncover a novel mechanism of action of evodiamine and indicate that evodiamine represents a potential targeted agent suitable to be combined with immunotherapeutic approaches to treat NSCLC cancer patients. MUC1-C overexpression is common in female, non-smoker, patients with advanced-stage adenocarcinoma. [ABSTRACT FROM AUTHOR]

Background: Non-small cell lung cancer (NSCLC) is the leading cause of cancer deaths primarily due to chemoresistance. Somatic mutation of TP53 (36%) and epidermal growth factor receptor (EGFR; > 30%) are major contributors to cisplatin (CDDP) resistance. Substantial evidence suggests the elevated levels of reactive oxygen species (ROS) is a key determinant in cancer. The elevated ROS can affect the cellular responses to chemotherapeutic treatments. Although the role of EGFR in PI3K/Akt signaling cascade in NSCLC is extensively studied, the molecular link between EGFR and p53 and the role of ROS in pathogenesis of NSCLC are limitedly addressed. In this study, we investigated the role of p53 in regulation of ROS production and EGFR signaling, and the chemosensitivity of NSCLC. Methods: In multiple NSCLC cell lines with varied p53 and EGFR status, we compared and examined the protein contents involved in EGFR-Akt-P53 signaling loop (EGFR, P-EGFR, Akt, P-Akt, p53, P-p53) by Western blot. Apoptosis was determined based on nuclear morphological assessment using Hoechst 33258 staining. Cellular ROS levels were measured by dichlorofluorescin diacetate (DCFDA) staining followed by flow cytometry analysis. Results: We have demonstrated for the first time that activation of p53 sensitizes chemoresistant NSCLC cells to CDDP by down-regulating EGFR signaling pathway and promoting intracellular ROS production. Likewise, blocking EGFR/PI3K/AKT signaling with PI3K inhibitor elicited a similar response. Our findings suggest that CDDP-induced apoptosis in chemosensitive NSCLC cells involves p53 activation, leading to suppressed EGFR signaling and ROS production. In contrast, in chemoresistant NSCLC, activated Akt promotes EGFR signaling by the positive feedback loop and suppresses CDDP-induced ROS production and apoptosis. Conclusion: Collectively, our study reveals that the interaction of the p53 and Akt feedback loops determine the fate of NSCLC cells and their CDDP sensitivity. [ABSTRACT FROM AUTHOR]