Molecular classification reveals the sensitivity of lung adenocarcinoma to radiotherapy and immunotherapy: multi-omics clustering based on similarity network fusion.

BACKGROUND: Due to individual differences in tumors and immune systems, the response rate to immunotherapy is low in lung adenocarcinoma (LUAD) patients. Combinations with other therapeutic strategies improve the efficacy of immunotherapy in LUAD patients. Although radioimmunotherapy has been demonstrated to effectively suppress tumors, the underlying mechanisms still need to be investigated. METHODS: Total RNA from LUAD cells was sequenced before and after radiotherapy to identify differentially expressed radiation-associated genes. The similarity network fusion (SNF) algorithm was applied for molecular classification based on radiation-related genes, immune-related genes, methylation data, and somatic mutation data. The changes in gene expression, prognosis, immune cell infiltration, radiosensitivity, chemosensitivity, and sensitivity to immunotherapy were assessed for each subtype. RESULTS: We used the SNF algorithm and multi-omics data to divide TCGA-LUAD patients into three subtypes. Patients with the CS3 subtype had the best prognosis, while those with the CS1 and CS2 subtypes had poorer prognoses. Among the strains tested, CS2 exhibited the most elevated immune cell infiltration and expression of immune checkpoint genes, while CS1 exhibited the least. Patients in the CS2 subgroup were more likely to respond to PD-1 immunotherapy. The CS2 patients were most sensitive to docetaxel and cisplatin, while the CS1 patients were most sensitive to paclitaxel. Experimental validation of signature genes in the CS2 subtype showed that inhibiting the expression of RHCG and TRPA1 could enhance the sensitivity of lung cancer cells to radiation. CONCLUSIONS: In summary, this study identified a risk classifier based on multi-omics data that can guide treatment selection for LUAD patients.

Association of Antihypertensive Drug-Related Gene Polymorphisms with Stroke in the Chinese Hypertensive Population.

Background: Antihypertensive therapy is crucial for preventing stroke in hypertensive patients. However, the efficacy of antihypertensive therapy varies across individuals, partially due to therapy-related genetic variations among individuals. We investigated the association of antihypertensive drug-related gene polymorphism with stroke in patients with hypertension. Methods: Demographic information, medication, and outcome data were obtained from a hypertensive patient management system, and a PCR fluorescence probe technique was used to detect 7 gene polymorphic loci (CYP2D6∗10, ADRB1, CYP2C9∗3, AGTR1, ACE, CYP3A5∗3, and NPPA), and these loci were compared between patients with and without stroke. Logistic regression was performed to analyze the association of these genetic variations with stroke risk in hypertensive patients while controlling for potential factors. Results: The prevalence of stroke in the hypertensive population in Changsha County of Hunan Province was 2.75%. The mutation frequencies of ADRB1 (1165G > C), CYP2D6∗10, CYP2C9∗3, AGTR1 (1166A > C), ACE (I/D), NPPA (2238T > C), and CYP3A5∗3 were 74.43%, 57.23%, 4.26%, 5.71%, 31.62%, 1.17%, and 69.58%, respectively. Univariate analysis revealed that ADRB1 polymorphism was associated with stroke (χ2 = 8.659, P < 0.05), with a higher stroke risk in the CC group than in the GC and GG groups (GC + GG). Multivariate unconditional logistic regression analysis showed that the CC genotype in ADRB1 (vs. the GC + GG genotype) was associated with an increased risk of stroke [odds ratio (OR) = 1.184, P<0.05] in hypertensive patients. No association was observed between CYP2D6∗10, CYP2C9∗3, AGTR1 (1166A > C), ACE (I/D), CYP3A5∗3, and NPPA (2238T > C) polymorphisms and stroke. Conclusions: ADRB1 (1165G > C) gene polymorphism is associated with the risk of stroke in Chinese hypertensive patients. The CC genotype is correlated with a higher risk of stroke than the GC + GG genotype.

Impact of digital finance on enterprise green innovation: From the perspective of information asymmetry, consumer demand and factor market distortions.

The study endeavors to empirically assess the influence of digital finance on promoting enterprise green innovation, while simultaneously probing its underlying mechanisms, by leveraging panel data from a sample of 2071 China A-share listed firms over an extensive time frame spanning from 2011 to 2021. The findings demonstrate that digital finance plays a crucial role in promoting enterprise green innovation, and that both the coverage breadth and usage depth of digital finance have a significant effect on enterprise green innovation, but the digitization level of digital finance also has a non-significant effect on enterprise green innovation, and the conclusions hold even after multiple robustness tests and consideration of endogeneity issues. Furthermore, heterogeneity analysis reveals that digital finance is only has a significant promoting effect on green innovation of SMEs, and high-tech enterprises. After conducting the mechanism analysis, it has been noted that digital finance serves as a facilitator in promoting green innovation in enterprises by reducing information asymmetry, stimulating consumer demand, and attenuating the distortion of regional factor markets. Intellectual property protection and environmental governance will strengthen the positive impact of digital finance on enterprises' green innovation. The research results provide policy implications for the green development of digital finance enabling enterprises.

hsa-miR-1301-3p Promotes the Proliferation and Migration of Nonsmall Cell Lung Cancer Cells and Reduces Radiosensitivity via Targeting Homeodomain-Only Protein Homeobox.

Background: There is increasing evidence that abnormal expression of microRNAs is involved in the occurrence and progression of tumors. In previous experiments, we found that the content of hsa-miR-1301-3p in tumor tissues of patients with nonsmall cell lung cancer (NSCLC) showed an obvious upward trend compared with that in normal tissues. We performed a detailed study on the impact and underlying mechanism of hsa-miR-1301-3p in NSCLC cells. Methods: The impact of hsa-miR-1301-3p on NSCLC cell proliferation, apoptosis, migration, and invasion was examined using colony formation, flow cytometry, modified Boyden chamber, and wound healing assays. Different doses of radiation were applied to NSCLC cells to investigate their sensitivity to radiotherapy. The potential target gene of hsa-miR-1301-3p was determined by dual-luciferase reporter assay and immunoblotting. Result: hsa-miR-1301-3p was upregulated in NSCLC tissues and cells. hsa-miR-1301-3p effectively promoted the rapid proliferation, migration, and invasion of NSCLC cells, while inhibiting apoptosis. It also induced radioresistance in NSCLC cells. hsa-miR-1301-3p targeted the homeodomain-only protein homeobox (HOPX) mRNA 3' untranslated region and inhibited its transcription in NSCLC cells. Exogenous HOPX overexpression antagonized the mechanism by which hsa-miR-1301-3p regulates NSCLC cell proliferation, metastasis, and apoptosis. Conclusions: hsa-miR-1301-3p plays an oncogenic role in the occurrence and development of NSCLC. By targeting HOPX, hsa-miR-1301-3p can not only promote the proliferation and metastasis of NSCLC cells, but also alleviate apoptosis and reduce radiosensitivity.

Predicting Malignancy of Thyroid Micronodules: Radiomics Analysis Based on Two Types of Ultrasound Elastography Images.

RATIONALE AND OBJECTIVES: To develop a multimodal ultrasound radiomics nomogram for accurate classification of thyroid micronodules. MATERIALS AND METHODS: A retrospective study including 181 thyroid micronodules within 179 patients was conducted. Radiomics features were extracted from strain elastography (SE), shear wave elastography (SWE) and B-mode ultrasound (BMUS) images. Minimum redundancy maximum relevance and least absolute shrinkage and selection operator algorithms were used to select malignancy-related features. BMUS, SE, and SWE radiomics scores (Rad-scores) were then constructed. Multivariable logistic regression was conducted using radiomics signatures along with clinical data, and a nomogram was ultimately established. The calibration, discriminative, and clinical usefulness were considered to evaluate its performance. A clinical prediction model was also built using independent clinical risk factors for comparison. RESULTS: An aspect ratio ≥ 1, mean elasticity index, BMUS Rad-score, SE Rad-score, and SWE Rad-score were identified as the independent predictors for predicting malignancy of thyroid micronodules by multivariable logistic regression. The radiomics nomogram based on these characteristics showed favorable calibration and discriminative capabilities (AUCs: 0.903 and 0.881 for training and validation cohorts, respectively), all outperforming clinical prediction model (AUCs: 0.791 and 0.626, respectively). The decision curve analysis also confirmed clinical usefulness of the nomogram. The significant improvement of net reclassification index and integrated discriminatory improvement indicated that multimodal ultrasound radiomics signatures might work as new imaging markers for classifying thyroid micronodules. CONCLUSION: The nomogram combining multimodal ultrasound radiomics features and clinical factors has the potential to be used for accurate diagnosis of thyroid micronodules in the clinic.

Ataxia telangiectasia mutated kinase inhibition promotes irradiation-induced PD-L1 expression in tumour-associated macrophages through IFN-I/JAK signalling pathway.

Tumour-associated macrophages (TAMs) are one of the primary sources of PD-L1 expression in the tumour microenvironment (TME). Ionizing radiation (IR) promotes PD-L1 expression in tumour cells. However, the effect of IR on macrophage PD-L1 expression and the underlying mechanisms remain unclear. ATM kinase, as the key kinase for initiating DNA damage repair (DDR) process, is associated with innate immune STING axis activation. Here, we explored the molecular mechanism implicated in macrophage PD-L1 expression regulated by IR as well as the role of ATM kinase in this process. IR-regulated PD-L1 expression in macrophages and associated signalling pathways were explored by in vitro studies using murine and human macrophage cell lines. A colorectal xenograft murine model was employed to demonstrate the impact of targeting ATM and PD-L1 expression in TAMs following IR on growth of tumour in vivo. IR up-regulated PD-L1 expression in macrophages, which was further augmented by ATM kinase inhibition. ATM inhibition increased IR-induced DNA damage, which activated STING/interferon regulatory factor 3 (IRF3) signalling pathway and up-regulated type I interferon (IFN-I) expression in macrophages. IFN-I bound to the IFN α receptor 1 on macrophages, activated the downstream JAK1 and STAT1/3 signalling and eventually led to PD-L1 up-expression. ATM inhibition augmented IR-induced PD-L1 expression in macrophages and CD8+ T cell infiltration, and promoted anti-tumour efficacy in vivo. These results suggested that ATM inhibition promoted IR-induced PD-L1 expression through the activation of innate immunity in TAMs, which provided a novel approach to enhance the anti-tumour efficacy of RT.

Nanoscale Zeolitic Imidazolate Framework (ZIF)-8 in Cancer Theranostics: Current Challenges and Prospects.

Cancer severely threatens human health and has remained the leading cause of disease-related death for decades. With the rapid advancement of nanomedicine, nanoscale metal-organic frameworks are believed to be potentially applied in the treatment and biomedical imaging for various tumors. Zeolite imidazole framework (ZIF)-8 attracts increasing attention due to its high porosity, large specific surface area, and pH-responsiveness. The designs and modifications of ZIF-8 nanoparticles, as well as the strategy of drug loading, demand a multifaceted and comprehensive understanding of nanomaterial features and tumor characteristics. We searched for studies on ZIF-8-based nanoplatforms in tumor theranostics on Web of Science from 2015 to 2022, mainly focused on the research published in the past 3 years, summarized the progress of their applications in tumor imaging and treatment, and discussed the favorable aspects of ZIF-8 nanoparticles for tumor theranostics as well as the future opportunities and potential challenges. As a kind of metal-organic framework material full of potential, ZIF-8 can be expected to be combined with more therapeutic systems in the future and continue to contribute to all aspects of tumor therapy and diagnosis.

PARP inhibitor plus radiotherapy reshapes an inflamed tumor microenvironment that sensitizes small cell lung cancer to the anti-PD-1 immunotherapy.

Small cell lung cancer (SCLC) is a highly malignant tumor with extremely poor prognosis. The treatment strategy is very limited, and patient outcomes remain dismal with the 5-year survival rate being mere 3-6%. Thus, novel therapeutic strategies for SCLC patients are urgently needed. In this study, we found that the triple-therapy of poly (ADP-ribose) polymerase (PARP) inhibitor, radiotherapy (RT) and anti-PD-1 treatment significantly inhibited tumor growth and prolonged survival in the syngeneic SCLC models in immunocompetent C57BL/6 mice. Mechanistically, we demonstrated that the combination of PARP inhibitor niraparib and RT reshaped an inflamed tumor microenvironment, including activation of the cGAS/STING immune response pathway, induction of immunogenic cell death, and upregulation of PD-L1 on tumor cells. Furthermore, this triple-therapy substantially augmented CD8+ T cell infiltration and activation, and enhanced anti-tumor effects as revealed by increased median survival time and reduced tumor volume without additional myelosuppression or hepatic injury. Together, our studies demonstrated that PARP inhibitor combined with RT potentiated anti-tumor immunity and enhanced the efficacy of anti-PD-1 immunotherapy in preclinical study, which provided a promising therapeutic strategy for SCLC patients in clinic.

SETD2 regulates gene transcription patterns and is associated with radiosensitivity in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) has high morbidity and mortality worldwide, and its prognosis remains unsatisfactory. Identification of epigenetic biomarkers associated with radiosensitivity is beneficial for precision medicine in LUAD patients. SETD2 is important in repairing DNA double-strand breaks and maintaining chromatin integrity. Our studies established a comprehensive analysis pipeline, which identified SETD2 as a radiosensitivity signature. Multi-omics analysis revealed enhanced chromatin accessibility and gene transcription by SETD2. In both LUAD bulk RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq), we found that SETD2-associated positive transcription patterns were associated with DNA damage responses. SETD2 knockdown significantly upregulated tumor cell apoptosis, attenuated proliferation and migration of LUAD tumor cells, and enhanced radiosensitivity in vitro. Moreover, SETD2 was a favorably prognostic factor whose effects were antagonized by the m6A-related genes RBM15 and YTHDF3 in LUAD. In brief, SETD2 was a promising epigenetic biomarker in LUAD patients.

GPR87 promotes tumor cell invasion and mediates the immunogenomic landscape of lung adenocarcinoma.

The purpose of this study is to examine the association between G protein-coupled receptor 87 (GPR87) and lung adenocarcinoma (LUAD) metastasis and immune infiltration. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets extract clinical data. According to the TCGA database, increased GPR87 expression predicts poor overall survival, progression-free interval, and disease-specific survival in LUAD patients. The meta-analysis also reveals a significant association between high GPR87 expression and poor overall survival. Moreover, functional experiments demonstrate that GPR87 silencing reduces LUAD cell invasion and migration. Immunoblotting shows that GPR87 knockdown decreased Vimentin and N-cadherin expression and increased E-cadherin expression in LUAD cells. GPR87 expression in LUAD is positively correlated with immune infiltration. In addition, GPR87 expression is associated with immune and chemotherapy resistance in LUAD patients. Our findings indicate that GPR87 promotes tumor progression and is correlated with immune infiltration, suggesting GPR87 as a possible biomarker for prognosis prediction in LUAD.

The Disease Burden of Primary Intracerebral Hemorrhage in Hunan Province, China in 2018.

BACKGROUND: Hunan Province is a region in China with a high prevalence of intracerebral hemorrhage, especially primary intracerebral hemorrhage (PICH). The objective of this observational study was to assess the disease burden of PICH. METHODS: We searched the Hunan Provincial Health Statistics Direct Reporting and Decision Analysis System to retrieve PICH inpatient and outpatient data and all-population all-cause deaths in Hunan Province in 2018. DisMod II was used to estimate the disability-adjusted life years (DALYs) due to PICH in 2018. RESULTS: In 2018, 30,400 new PICH cases were recorded in Hunan Province. The incidence was higher among men (51.6 per 100,000) than women (29.3 per 100,000). The DALYs due to PICH were 478,000 patient-years, the years of life lost (YLLs) were 452,000 patient-years and the years lived with disability (YLDs) were 27,000 patient-years. In 2018, the rate of DALYs due to PICH was 6.4 patient-years per 1000 individuals, the rate of YLLs was 6.1 patient-years per 1000 individuals, and the rate of YLDs was 0.3 patient-years per 1000 individuals. CONCLUSION: We estimated the DALYs due to PICH in Hunan Province in 2018, thereby providing relevant data for the development of policies and measures for the management of PICH disease burden.

Tumor stemness and immune infiltration synergistically predict response of radiotherapy or immunotherapy and relapse in lung adenocarcinoma.

Cancer stem cells (CSCs) have been shown to accelerate tumor recurrence, radiotherapy, and chemotherapy resistance. Immunotherapy is a powerful anticancer treatment that can significantly prolong the overall survival of patients with lung adenocarcinoma (LUAD). However, little is known about the function of genes related to tumor stemness and immune infiltration in LUAD. After integrating the tumor stemness index based on mRNA expression (mRNAsi), immune score, mRNA expression, and clinical information from the TCGA database, we screened 380 tumor stemness and immune (TSI)-related genes and constructed a five TSI-specific-gene (CPS1, CCR2, NT5E, ANLN, and ABCC2) signature (TSISig) using a machine learning method. Survival analysis indicated that TSISig could stably predict the prognosis of patients with LUAD. Comparison of mRNAsi and immune score between high- and low-TSISig groups suggested that TSISig characterized tumor stemness and immune infiltration. In addition, enrichment of immune subpopulations showed that the low-TSISig group held more immune subpopulations. GSEA revealed that TSISig had a strong association with the cell cycle and human immune response. Further analysis revealed that TSISig not only had a good predictive ability for prognosis but could also serve as an excellent predictor of tumor recurrence and response to radiotherapy and immunotherapy in LUAD patients. TSISig might regulate the development of LUAD by coordinating tumor stemness and immune infiltration. Finally, a connectivity map (CMap) analysis demonstrated that the HDAC inhibitor could target TSISig.

Mechanisms and management of 3rd­generation EGFR­TKI resistance in advanced non­small cell lung cancer (Review).

Targeted therapy with epidermal growth factor receptor (EGFR)­tyrosine kinase inhibitors (TKIs) is a standard modality of the 1st­line treatments for patients with advanced EGFR­mutated non­small cell lung cancer (NSCLC), and substantially improves their prognosis. However, EGFR T790M mutation is the primary mechanism of 1st­ and 2nd­generation EGFR­TKI resistance. Osimertinib is a representative of the 3rd­generation EGFR­TKIs that target T790M mutation, and has satisfactory efficacy in the treatment of T790M­positive NSCLC with disease progression following use of 1st­ or 2nd­generation EGFR­TKIs. Other 3rd­generation EGFR­TKIs, such as abivertinib, rociletinib, nazartinib, olmutinib and alflutinib, are also at various stages of development. However, the occurrence of acquired resistance is inevitable, and the mechanisms of 3rd­generation EGFR­TKI resistance are complex and incompletely understood. Genomic studies in tissue and liquid biopsies of resistant patients reveal multiple candidate pathways. The present review summarizes the recent findings in mechanisms of resistance to 3rd­generation EGFR­TKIs in advanced NSCLC, and provides possible strategies to overcome this resistance. The mechanisms of acquired resistance mainly include an altered EGFR signaling pathway (EGFR tertiary mutations and amplification), activation of aberrant bypassing pathways (hepatocyte growth factor receptor amplification, human epidermal growth factor receptor 2 amplification and aberrant insulin­like growth factor 1 receptor activation), downstream pathway activation (RAS/RAF/MEK/ERK and PI3K/AKT/mTOR) and histological/phenotypic transformations (SCLC transformation and epithelial­mesenchymal transition). The combination of targeted therapies is a promising strategy to treat osimertinib­resistant patients, and multiple clinical studies on novel combined therapies are ongoing.

HHLA2 deficiency inhibits non-small cell lung cancer progression and THP-1 macrophage M2 polarization.

BACKGROUND: Human endogenous retrovirus-H long terminal repeat-associating protein 2 (HHLA2) is a member of B7 family, which is upregulated in multiple tumors. However, its exact functions in non-small cell lung cancer (NSCLC) have not been fully understood. This study aimed to investigate the biological roles of HHLA2 in human NSCLC and the relevant mechanisms. In addition, the effects of tumor cell-derived HHLA2 on tumor-associated macrophage (TAM) polarization were explored. METHODS: NSCLC cell growth, migration, and invasion were assessed by colony formation and modified Boyden chamber assays. Cell cycle and the CD163+ TAMs were examined by flow cytometry. A co-culture model of THP-1 macrophages and NSCLC cells was conducted to investigate the impacts of tumor cell-derived HHLA2 on THP-1 macrophage polarization. Moreover, a xenograft nude mouse model was established to explore the effects of HHLA2 on tumorigenesis in vivo. RESULTS: HHLA2 was upregulated in A549 and H1299 cells compared with the normal lung epithelial BEAS-2B cells. HHLA2 deficiency inhibited NSCLC cell proliferation, migration, invasion, and induced G0/G1 phase arrest partially via inhibiting EGFR/MAPK/ERK signaling pathway. Furthermore, HHLA2 knockdown inhibited M2 polarization of TAMs via downregulating IL-10. In addition, knockdown of HHLA2 inhibited tumor growth in vivo. CONCLUSION: HHLA2 downregulation inhibited NSCLC growth and TAM M2 polarization. HHLA2 may serve as a therapeutic target and promising prognostic biomarker in NSCLC.

MUC3A induces PD-L1 and reduces tyrosine kinase inhibitors effects in EGFR-mutant non-small cell lung cancer.

The immune checkpoint ligand programmed death-ligand 1 (PD-L1) and the transmembrane mucin (MUC) 3A are upregulated in non-small cell lung cancer (NSCLC), contributing to the aggressive pathogenesis and poor prognosis. Here, we report that knocking down the oncogenic MUC3A suppresses the PD-L1 expression in NSCLC cells. MUC3A is a potent regulator of epidermal growth factor receptor (EGFR) stability, and MUC3A deficiency downregulates the activation of the PI3K/Akt and MAPK pathways, which subsequently reduces the expression of PD-L1. Furthermore, knockdown of MUC3A and tyrosine kinase inhibitors (TKIs) in EGFR-mutant NSCLC cells play a synergistic effect on inhibited proliferation and promoted apoptosis in vitro. In the BALB/c nude mice xenograft model, MUC3A deficiency enhances EGFR-mutated NSCLC sensitivity to TKIs. Our study shows that transmembrane mucin MUC3A induces PD-L1, thereby promoting immune escape in NSCLC, while downregulation of MUC3A enhances TKIs effects in EGFR-mutant NSCLC. These findings offer insights into the design of novel combination treatment for NSCLC.

Hollow PtCo alloy nanospheres as a high-Z and oxygen generating nanozyme for radiotherapy enhancement in non-small cell lung cancer.

Radiotherapy, as well as chemotherapy and surgery, occupies an essential position in tumor treatment. Nonetheless, insufficient radiation deposition and hypoxia-related radioresistance of cancer cells still are serious challenges in radiotherapy. Herein, we proposed a hollow PtCo nanosphere (PtCo NS)-based novel radiosensitizer with three advantages to sensitize tumor radiotherapy: (i) the high-Z element Pt ensured higher radiation absorption to cause more DNA damage, (ii) the platinum (Pt) and cobalt (Co) elements exhibited a dual catalase-like enzymatic activity to convert endogenic H2O2 to O2 efficiently, and (iii) the unique hollow nature of the PtCo NS provided a large specific surface area, which could amplify the catalytic reaction of H2O2 to induce reactive oxygen species and cancer cell apoptosis upon combination with radiation. Both in vivo and in vitro studies showed that the hollow PtCo NS could significantly inhibit tumor growth, simultaneously relieving tumor hypoxia with good biocompatibility and biosafety. This work presents a simple but multifunctional radiosensitizer with a unique hollow structure for radiotherapy enhancement.

RRM2 silencing suppresses malignant phenotype and enhances radiosensitivity via activating cGAS/STING signaling pathway in lung adenocarcinoma.

BACKGROUND: As one of the most common malignancy, lung adenocarcinoma (LUAD) is characterized by low 5-year survival rate. This research aimed to investigate the effects of ribonucleotide reductase regulatory subunit M2 (RRM2) on malignant biological behaviors and activation of cGAS/STING pathway. We also explored the synergistic sensitization mechanisms of RRM2 and radiotherapy. METHODS: Bioinformatic tools were used to evaluate the clinical significance of RRM2 in LUAD patients. The roles of RRM2 in malignant phenotype and DNA damage in LUAD cells were investigated with cell proliferation, colony formation, immunofluorescence, modified Boyden chamber and comet assays. The mouse models were used to evaluate the biological significance of RRM2 in vivo. Cytotoxic T cell infiltration was evaluated via flow cytometric analysis and immunohistochemistry staining in C57BL/6 mice. We also explored the synergistic effects of RRM2 silencing and radiation on LUAD cells with apoptosis assay and immunoblotting in vitro. RESULTS: Bioinformatic analysis revealed that RRM2 had diagnostic values for LUAD patients. Higher levels of RRM2 predicted worse prognosis. RRM2 silencing inhibited LUAD cell proliferation, invasion and migration. RRM2 knockdown induced S phase arrest and DNA damage. RRM2 silencing induced cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) pathway, and the downstream targets were regulated in a STING-dependent manner. Knockdown of RRM2 suppressed tumor growth in the xenograft tumor models. RRM2 deficiency increased CD8 + T cells in the tumor tissues and spleens. Furthermore, RRM2 silencing had synergistic effects with radiation on inhibiting cell proliferation and promoting apoptosis. Meanwhile, this combination promoted the activation of cGAS/STING signaling pathway synergistically, and simultaneously increased expression of IFNß, CCL5 and CXCL10. CONCLUSION: Our results demonstrated that RRM2 silencing had anti-tumor values and activated the cGAS/STING signaling pathway. RRM2 silencing increased CD8 + T cells infiltration. RRM2 silencing cooperated with radiation to inhibit LUAD cell proliferation, promote apoptosis and enhance the activation of cGAS/STING signaling pathway. RRM2 could be a promising target for tumor regression through cancer immunotherapy in LUAD.

Agrin Promotes Non-Small Cell Lung Cancer Progression and Stimulates Regulatory T Cells via Increasing IL-6 Secretion Through PI3K/AKT Pathway.

Non-small cell lung cancer (NSCLC) has high mortality rates worldwide. Agrin contributes to immune synapse information and is involved in tumor metastasis. However, its roles in NSCLC and tumor immune microenvironment remain unclear. This study examined the effects and the underlying mechanisms of Agrin in NSCLC and tumor-infiltrated immune cells. Clinical tissue samples were used to confirm the bioinformatic predictions. NSCLC cells were used to investigate the effects of Agrin on cell cycle and proliferation, as well as invasion and migration. Tumor xenograft mouse model was used to confirm the effects of Agrin on NSCLC growth and tumor-infiltrated regulatory T cells (Tregs) in vivo. Agrin levels in NSCLC cells were closely related to tumor progression and metastasis, and its function was enriched in the PI3K/AKT pathway. In vitro assays demonstrated that Agrin knockdown suppressed NSCLC cell proliferation and metastasis, while PI3K/AKT activators reversed the inhibitory effects of Agrin deficiency on NSCLC cell behaviors. Agrin expression was negatively associated with immunotherapy responses in NSCLC patients. Agrin knockdown suppressed Tregs, as well as interleukin (IL)-6 expression and secretion, while PI3K/AKT activators and exogenous IL-6 rescued the inhibitory effects. In the mouse model, Agrin downregulation alleviated NSCLC cell growth and Treg infiltration in vivo. Our results indicated that Agrin promotes tumor cell growth and Treg infiltration via increasing IL-6 expression and secretion through PI3K/AKT pathway in NSCLC. Our studies suggested Agrin as a therapeutically potential target to increase the efficacy of immunotherapy in NSCLC patients.