Lung Adenocarcinoma Metastasis Research Articles

Lymph node metastasis and its risk factors in T1 lung adenocarcinoma.

In this study, the focus was primarily on examining the occurrence of lymph node metastasis in T1 lung adenocarcinoma, while also analyzing the relationship between clinical variables such as imaging characteristics, pathological classifications, and lymph node metastasis. We retrospectively analyzed data from patients with T1 lung adenocarcinoma who underwent lobectomy and lymph node dissection between January 2016 and December 2019. Utilizing univariate and multivariate analyses, we assessed the associations between lymph node metastasis and various clinical factors, including imaging characteristics, lesion location and depth, and pathological subtypes. Of the 433 patients with T1 lung adenocarcinoma, 139 had lymph node metastasis. Moreover, the incidence of node 1 (N1) lymph node, sequential, and node 2 (N2) skip metastases were 12.2%, 12.7%, and 7.2%, respectively. Univariate analysis revealed that tumor diameter, depth ratio, sex, invasive imaging features, and pathological subtype were significantly associated with lymph node metastasis. Multivariate analysis revealed that the tumor depth ratio, tumor diameter, pleural indentation or traction sign, nonvascular penetration sign, solid component, nonadherence, and micropapillary pathological subtype were risk factors for lymph node metastasis. In the multivariate analysis, the micropapillary pathological subtype was an independent risk factor for N2 skip metastasis. In patients with clinical stage T1 lung adenocarcinoma, the risk of lymph node metastasis is higher for tumors located deep within the lung tissue with solid components, invasive preoperative imaging features, and larger diameters. For N2 skip lymph node metastasis, the micropapillary pathological subtype represents a significant high-risk factor.

Multi-omics immune regulatory mechanisms in lung adenocarcinoma metastasis and survival time

Lung adenocarcinoma (LUAD) is the most common type of lung cancer. Despite previous research on immune mechanisms and related molecules in LUAD, the specific regulatory mechanisms of these molecules in the immune microenvironment remain unclear. Furthermore, the impact of regulatory genes or RNA on LUAD metastasis and survival time is yet to be understood.To address these gaps, we collected a substantial amount of data, including 17,226 gene expression profiles from 1,018 samples, 370,640 methylation sites from 461 samples, and 248 miRNAs from 513 samples. Our aim was to explore the genes, miRNAs, and methylation sites associated with LUAD progression. Leveraging the regulatory functions of miRNAs and methylation sites, we identified target and regulated genes. Through the utilization of LASSO and survival analysis, we pinpointed 22 key genes that play pivotal roles in the immune regulatory mechanism of LUAD. Notably, the expression levels of these 22 genes demonstrated significant discriminatory power in predicting LUAD patient survival time. Additionally, our deep learning model accurately predicted distant metastasis in LUAD patients using the expression levels of these genes.Further pathway enrichment analysis revealed that these 22 genes are significantly enriched in pathways closely linked to LUAD progression. Through Immune Infiltration Assay, we observed that T cell CD4 memory resting, monocytes, and macrophages.M2 were the three most abundant cell types in the immune microenvironment of LUAD. These cells are known to play crucial roles in tumor growth, invasion, and metastasis. Single-cell data analysis further validated the functional significance of these genes, indicating their involvement not only in immune cells but also in epithelial cells, showcasing significant differential expression.Overall, this study sheds light on the regulatory mechanisms underlying the immune microenvironment of LUAD by identifying key genes associated with LUAD progression. The findings provide insights into potential prognostic markers and therapeutic targets.

Metastasis-related long non-coding RNAs AL359220.1, SH3BP5-AS1 and ZF-AS1 are significant for prognostic assessment of lung adenocarcinoma.

Metastasis of lung adenocarcinoma (LUAD) severely worsens prognosis. Genetic alteration in the tumor microenvironment (TME) is closely associated with metastasis and other malignant biological properties of LUAD. In this study, we establish a metastasis-related risk model to accurately predict LUAD prognosis. RNA-sequencing profiles and clinical data of LUAD patients including 503 tumor tissues and 54 adjacent normal tissues were collected in TCGA database. Additionally, the paired specimens from 156 LUAD patients were obtained in a single center. The metastatic relevance and clinical significance of metastasis-related long non-coding RNA (MRLNRs) was validated by series of in vitro experiments including western blotting, qPCR and transwell assays. Six MRLNRs were significantly correlated to prognoses of LUAD patients, of which AL359220.1, SH3BP5-AS1 and ZF-AS1 were further used to establish a metastasis-related risk scoring model (MRRS) due to the close associations with overall survival of LUAD patients. According to the MRRS, patients with higher scores in the high-risk group obtained poorer prognoses and survival outcomes. ZFAS1 expressed highly in tumor tissues and showed the inverse results compared to SH3BP5-AS1 and AL359220.1. In addition, the high expression of ZFAS1 was prominently correlated to the more advanced T-stage and distant metastasis. The reduction of ZFAS1 induced by siRNAs dramatically diminished the migration and invasion abilities of LUAD cells. In the present research, we elucidate the metastatic relevance and clinical significance of AL359220.1, SH3BP5-AS1 and ZF-AS1 in LUAD. Moreover, MRRS provide a promising assessing model for clinical decision making and prognosis of LUAD.

Prognostic and immune infiltrative biomarkers of CENPO in pan–cancer and its relationship with lung adenocarcinoma cell proliferation and metastasis

BackgroundThe centromere protein O (CENPO) is an important member of the centromere protein family. However, the role of CENPO in pan–cancer and immune infiltration has not been reported. Here, we investigated the role of CENPO in pan–cancer and further validated its role in lung adenocarcinoma (LUAD) by in vitro experiments.MethodThe UCSC Xena database and The Cancer Genome Atlas (TCGA)–LUAD data were used to assess the expression levels of CENPO. The potential value of CENPO as a diagnostic and prognostic biomarker for pan–cancer was evaluated using TCGA data and the GEPIA database. The -expression profiles of LUAD patients and the corresponding clinical data were downloaded for correlation analysis. The role of CENPO in immune infiltration was investigated using the UCSC Xena database. Subsequently, qRT–PCR was performed to detect the expression of CENPO. Cell proliferation, migration, and invasion were determined using CCK–8, wound–healing assay, and transwell assay, respectively.ResultsCENPO is highly expressed in most cancers, and the upregulation of CENPO is associated with poor prognosis in many cancers. CENPO expression correlates with age, TNM stage, N stage, T stage, and receipt of radiotherapy in LUAD patients, and LUAD patients with high CENPO expression have poorer overall survival (OS) and disease–free survival (DFS). In addition, CENPO expression is associated with immune cell infiltration and immune checkpoint inhibitors. Moreover, the expression of CENPO was closely related to the expression of tumor mutational load and microsatellite instability. In vitro experiments showed that CENPO expression was increased in LUAD cell lines and that knockdown of CENPO significantly inhibited the proliferation, cell invasion, and migration ability of LUAD cells.ConclusionCENPO may be a potential pan–cancer biomarker and oncogene, especially in LUAD. In addition, CENPO is associated with immune cell infiltration and may serve as a new molecular therapeutic target and effective prognostic marker for LUAD.

Histone deacetylase inhibitors inhibit lung adenocarcinoma metastasis via HDAC2/YY1 mediated downregulation of Cdh1

Metastasis is a leading cause of mortality in patients with lung adenocarcinoma. Histone deacetylases have emerged as promising targets for anti-tumor drugs, with histone deacetylase inhibitors (HDACi) being an active area of research. However, the precise mechanisms by which HDACi inhibits lung cancer metastasis remain incompletely understood. In this study, we employed a range of techniques, including qPCR, immunoblotting, co-immunoprecipitation, chromatin-immunoprecipitation, and cell migration assays, in conjunction with online database analysis, to investigate the role of HDACi and HDAC2/YY1 in the process of lung adenocarcinoma migration. The present study has demonstrated that both trichostatin A (TSA) and sodium butyrate (NaBu) significantly inhibit the invasion and migration of lung cancer cells via Histone deacetylase 2 (HDAC2). Overexpression of HDAC2 promotes lung cancer cell migration, whereas shHDAC2 effectively inhibits it. Further investigation revealed that HDAC2 interacts with YY1 and deacetylates Lysine 27 and Lysine9 of Histone 3, thereby inhibiting Cdh1 transcriptional activity and promoting cell migration. These findings have shed light on a novel functional mechanism of HDAC2/YY1 in lung adenocarcinoma cell migration.

Single-cell transcriptomics reveals the drivers and therapeutic targets of lymph node metastasis in lung adenocarcinoma.

Lymph node metastasis (LNM) is usually the most common metastatic pathway in lung adenocarcinoma (LUAD) and is associated with a poorer prognosis and higher possibility of recurrence. Therefore, discovering the drivers and therapeutic targets of LNM is important for early and non-invasive detection of patients with a high risk of LNM and guiding individualized therapy. Various cell constitutions of the primary tumor and lymph node microenvironment was characterized based on scRNA-seq data. The copy number variation (CNV) analysis was performed to probe clonal structures and origins of metastatic lymph nodes, and found 6q loss and 20q gain may drive LNM in LUAD. Then a LNM-related cell subset, named Scissor+ cells, was identified using the Scissor algorithm. And cell-cell communication network among Scissor+ cells and microenvironment was further analyzed. Besides, a pro-LNM signature was subsequently constructed based on 27 genes using pseudotime trajectory analysis and gene set variation analysis. The pro-LNM signature showed a significant correlation with N stage and a good predictive ability of LUAD survival. At last, we identified that erastin and gefitinib could potentially inhibit LNM by targeting Scissor+ cells based on the drug sensitivity data of the cancer cell lines, which provided new insights for LUAD therapy.

Expression of MEF2D in Lung Adenocarcinoma and Its Correlation with Prognosis

Myocyte enhancer factor 2D (MEF2D) can participate in the process of tumor lesions by regulating the transcription of oncogenes. In a previous study, MEF2D was demonstrated to enhance the proliferation and metastasis of lung adenocarcinoma cells A549 and H1299 by promoting the transcription of NUSAP1. The research aimed to explore the expression level and clinical significance of MEF2D in lung adenocarcinoma. A total of 199 patients with lung adenocarcinoma were collected. Immunohistochemical staining was used to detect MEF2D expression levels in cancer and adjacent tissues. After the clinical and follow-up data were collated, the correlation between MEF2D expression level and clinical characteristics and prognosis of the patients was analyzed. In the lung adenocarcinoma, the high expression rate of MEF2D in cancer tissues was significantly higher than that in adjacent tissues (P<0.05). According to immunohistochemical score, MEF2D expression level in lung adenocarcinoma tissues was correlated with tumor differentiation, N stage, M stage and intrapulmonary metastasis (P<0.05). Kaplan-Meier analysis showed that patients with low MEF2D expression had significantly better prognosis than patients with high MEF2D expression (P<0.05). Cox multivariate analysis showed that MEF2D expression level, M stage, N stage and bone metastasis of lung cancer were independent risk factors for prognosis of lung adenocarcinoma patients. MEF2D expression level is closely related to the metastasis of lung adenocarcinoma and other clinical characteristics, and can be used as an independent risk factor for the prognosis of patients with lung adenocarcinoma, which has the potential to be developed as a clinical diagnosis and treatment target of lung adenocarcinoma.

ARHGAP9 knockdown promotes lung adenocarcinoma metastasis by activating Wnt/β-catenin signaling pathway via suppressing DKK2

This study aims to elucidate the effect of ARHGAP9 on lung adenocarcinoma (LUAD) metastasis, and preliminarily explore its molecular mechanism. As a result, we found that ARHGAP9 was downregulated and correlated with poor prognosis of LUAD. ARHGAP9 knockdown promoted LUAD cell proliferation, migration and invasion, inhibited cell apoptosis and reduced G0G1 cell cycle arrest, in contrast to the results of ARHGAP9 overexpression. Further RNA sequencing analysis demonstrated that ARHGAP9 knockdown in H1299 cells significantly reduced DKK2 (dickkopf related protein 2) expression. Silencing ARHGAP9 in H1299 cells while overexpressing DKK2, DKK2 reversed the promoted effects of ARHGAP9 knockdown on LUAD cell proliferation, migration and invasion. Meanwhile, the activity of Wnt/β-catenin signaling pathway was also reduced. Taken together, these data indicated that ARHGAP9 knockdown promoted LUAD metastasis by activating Wnt/β-catenin signaling pathway via suppressing DKK2. This may provide a new strategy for LUAD treatment.

Clinical characteristics and establishment of a 2-year-OS predictive model of EGFR mutation-positive patients with pleural invasion of lung adenocarcinoma.

To investigate the differences between lung adenocarcinoma with the pleural invasion that has EGFR (epidermal growth factor receptor) 19-del or 21L858R mutations in terms of clinical characteristics and outcomes. EGFR mutation-positive patients with pleural metastasis of lung adenocarcinoma diagnosed in the Department of Respiratory Medicine of Yuhuangding Hospital of Yantai City, Shandong Province, from January 2014 to January 2022 were selected. The clinical data of the patients were collected to retrospectively analyze whether the clinical characteristics and prognosis of patients with 19-del or 21L858R mutation subtype were different and analyze the impact of clinical characteristics on the prognosis of patients. The difference in clinical characteristics between the 2 groups was analyzed by SPSS, P < .05. There was statistical significance. Univariate and multivariate regression analysis was performed with R soft. To establish a 2-year overall survival predictive model for patients with EGFR gene 19-del and 21L858R mutations in patients with pleural invasion of lung adenomas and to provide predictive model maps. Receiver operating characteristic curve, calibration curve, and decision curve analysis were used to evaluate the value of the prediction model in this study. Of the 74 patients included, the 19-del mutation group had a higher incidence of pleural thickening (P = .023) and a lower Ki-67 level (P = .035). There was no difference in 2-year overall survival and progression-free survival between the 2 mutations. There were differences in pleural thickening and Ki-67 index between the 2 groups, but no differences in disease outcome between the 2 groups. The nomogram model established based on gender, treatment regimen, CEA, lymph node metastasis, and pleural changes is accurate and feasible.

EGFL6 promotes bone metastasis of lung adenocarcinoma by increasing cancer cell malignancy and bone resorption.

Lung adenocarcinoma is the most common and aggressive type of lung cancer with the highest incidence of bone metastasis. Epidermal growth factor-like domain multiple 6 (EGFL6) is an exocrine protein, and the expression of EGFL6 is correlated with survival of patient with lung adenocarcinoma. However, the association between EGFL6 expression in lung adenocarcinoma and bone metastasis has not been investigated. In this study, we found that EGFL6 levels in lung adenocarcinoma tissues correlate with bone metastasis and TNM stages in surgical patients. In vitro, overexpression of EGFL6 in lung adenocarcinoma cells promoted their proliferation, migration, and invasion ability compared with control by enhancing EMT process and activating Wnt/β-catenin and PI3K/AKT/mTOR pathways. In the nude mouse model, overexpression of EGFL6 enhanced tumor growth and caused greater bone destruction. Moreover, the exocrine EGFL6 of human lung adenocarcinoma cells increased osteoclast differentiation of bone marrow mononuclear macrophages (BMMs) of mice via the NF-κB and c-Fos/NFATc1 signaling pathways. However, exocrine EGFL6 had no effect on osteoblast differentiation of bone marrow mesenchymal stem cells (BMSCs). In conclusion, high expression of EGFL6 in lung adenocarcinomas is associated with bone metastasis in surgical patients. The underlying mechanism may be the increased metastatic properties of lung adenocarcinoma cells with high EGFL6 level and the enhanced osteoclast differentiation and bone resorption by exocrine EGFL6 from tumors. Therefore, EGFL6 is a potential therapeutic target to reduce the ability of lung adenocarcinomas to grow and metastasize and to preserve bone mass in patients with bone metastases from lung adenocarcinomas.

M6A methylation reader IGF2BP2 activates endothelial cells to promote angiogenesis and metastasis of lung adenocarcinoma

BackgroundLung adenocarcinoma (LUAD) is a common type of lung cancer with a high risk of metastasis, but the exact molecular mechanisms of metastasis are not yet understood.MethodsThis study acquired single-cell transcriptomics profiling of 11 distal normal lung tissues, 11 primary LUAD tissues, and 4 metastatic LUAD tissues from the GSE131907 dataset. The lung multicellular ecosystems were characterized at a single-cell resolution, and the potential mechanisms underlying angiogenesis and metastasis of LUAD were explored.ResultsWe constructed a global single-cell landscape of 93,610 cells from primary and metastatic LUAD and found that IGF2BP2 was specifically expressed both in a LUAD cell subpopulation (termed as LUAD_IGF2BP2), and an endothelial cell subpopulation (termed as En_IGF2BP2). The LUAD_IGF2BP2 subpopulation progressively formed and dominated the ecology of metastatic LUAD during metastatic evolution. IGF2BP2 was preferentially secreted by exosomes in the LUAD_IGF2BP2 subpopulation, which was absorbed by the En_IGF2BP2 subpopulation in the tumor microenvironment. Subsequently, IGF2BP2 improved the RNA stability of FLT4 through m6A modification, thereby activating the PI3K-Akt signaling pathway, and eventually promoting angiogenesis and metastasis. Analysis of clinical data showed that IGF2BP2 was linked with poor overall survival and relapse-free survival for LUAD patients.ConclusionsOverall, these findings provide a novel insight into the multicellular ecosystems of primary and metastatic LUAD, and demonstrate that a specific LUAD_IGF2BP2 subpopulation is a key orchestrator promoting angiogenesis and metastasis, with implications for the gene regulatory mechanisms of LUAD metastatic evolution, representing themselves as potential antiangiogenic targets.

Diagnostic gastrointestinal markers in primary lung cancer and pulmonary metastases

Histopathological diagnosis of pulmonary tumors is essential for treatment decisions. The distinction between primary lung adenocarcinoma and pulmonary metastasis from the gastrointestinal (GI) tract may be difficult. Therefore, we compared the diagnostic value of several immunohistochemical markers in pulmonary tumors. Tissue microarrays from 629 resected primary lung cancers and 422 resected pulmonary epithelial metastases from various sites (whereof 275 colorectal cancer) were investigated for the immunohistochemical expression of CDH17, GPA33, MUC2, MUC6, SATB2, and SMAD4, for comparison with CDX2, CK20, CK7, and TTF-1. The most sensitive markers for GI origin were GPA33 (positive in 98%, 60%, and 100% of pulmonary metastases from colorectal cancer, pancreatic cancer, and other GI adenocarcinomas, respectively), CDX2 (99/40/100%), and CDH17 (99/0/100%). In comparison, SATB2 and CK20 showed higher specificity, with expression in 5% and 10% of mucinous primary lung adenocarcinomas and both in 0% of TTF-1-negative non-mucinous primary lung adenocarcinomas (25–50% and 5–16%, respectively, for GPA33/CDX2/CDH17). MUC2 was negative in all primary lung cancers, but positive only in less than half of pulmonary metastases from mucinous adenocarcinomas from other organs. Combining six GI markers did not perfectly separate primary lung cancers from pulmonary metastases including subgroups such as mucinous adenocarcinomas or CK7-positive GI tract metastases. This comprehensive comparison suggests that CDH17, GPA33, and SATB2 may be used as equivalent alternatives to CDX2 and CK20. However, no single or combination of markers can categorically distinguish primary lung cancers from metastatic GI tract cancer.

Establishment of a nomogram predictive model for survival and prognosis of 97 patients with different subtypes of lung adenocarcinoma after radical resection.

e20596 Background: Postoperative recurrence and metastasis of lung adenocarcinoma (LUAD) is a major obstacle to long-term survival, and how to identify patients at high risk of recurrence / death after surgery and those likely to benefit from adjuvant therapy is currently a clinically relevant question. In this study, we investigated the survival characteristics of patients with different subtypes of LUAD after radical resection and established predictive prognostic models to inform postoperative management, recurrence prediction and risk management in lung cancer patients. Methods: A retrospective analysis of 97 patients who underwent concurrent genetic testing for LUAD radical resection at The Affiliated Tumor Hospital of Xinjiang Medical University between December 01, 2014 and December 30, 2017 was performed. A COX proportional risk regression model was used to construct a prognosis model for patients with LUAD after surgery and visualization of the model was performed using column diagrams. The performance of the model was evaluated using C index, calibration curve, and ROC curve. Results: (1)46 patients (47.42%) were included and 51 patients died (52.58%), with a median survival of 78 months (95% CI: 63-93). Twenty of these patients had a good prognosis (20.62%) and 77 had a poor prognosis (79.38%), with a median survival time of 88 months (95% CI: 81-95). The overall survival rate was 98.9%, 78.3% and 59.7%, respectively, and the cumulative disease-free survival rate was 77.3%, 37.1% and 20.6%, respectively, for 1, 3 and 5 years. Pathologic types were lepidic, acina/papillaryand solid/micropapillary with 87.50%, 56.90% and 58.80% OS and DFS, respectively. 37.50%、80%、11.80%. (2)26 patients (26.8%)had recurrent metastasis,the main site of metastasis was extrapulmonary, and multiple metastases were more common. (3)Univariateand multivariate analysis showed that TNM stage III, pathological classification as solid/micropapillary, tumor diameter ≥ 3cm, and gene mutation positivity were independent risk factors for prognosis in patients with lung adenocarcinoma after surgery. Based on the above risk factors, the Nomogram prognostic model was established with a C index of 0.687 (95% CI: 0.622-0.752) and calibration curves and ROCs for the 1, 3, and 5 year models, respectively, with AUC values of 0.742, 0.752, and 0.820 &gt; 0.7, suggesting that the model is within the acceptable range of partitioning and accuracy, with the highest AUC for the 5-year DFS prediction. Conclusions: High TNM staging, pathotyping of micronipples or entities, ≥ 3cm tumor diameter, and mutant positivity were independent risk factors for recurrence and metastasis in patients with LUAD. The Nomogram predictive model based on patient risk factors after LUAD radical resection is effective in predicting long-term survival and guiding personalized treatment.

LINC00943 regulates miR-1252-5p/YWHAH axis to promote tumor proliferation and metastasis in lung adenocarcinoma

Lung cancer is the most common malignant tumor worldwide. In recent years, the incidence of lung adenocarcinoma (LAD) has increased significantly, with an unfavorable 5-year survival rate. Long non-coding RNAs (lncRNAs) have been shown to play a significant role in the emergence, growth, and metastasis of tumors. However, the functional role and mechanism of LINC00943 in LAD progression have not yet been investigated. Aberrant expressions of LINC00943, miR-1252-5p, and YWHAH were determined by RT-qPCR and Western blot analyses. The binding relationship between miR-1252-5p and LINC00943 or YWHAH was examined by Pearson's correlation analysis, RNA pull-down, and dual-luciferase reporter assays. MTT assay was conducted to measure cell viability and colony formation assay was performed to evaluate cell proliferation potential. Transwell assay was used to investigate cell migration and invasion and flow cytometry was applied to evaluate cell apoptosis. We found that LINC00943 was highly expressed in LAD tissue samples and cell lines and was a reliable biomarker with high sensitivity, and specificity (P < 0.0001; AUC: 0.8966) for LAD detection. LINC00943 was mainly localized in the cytoplasm. In vitro, LINC00943 promoted LAD cell proliferation, migration, and invasion; however, silencing LINC00943 inhibited LAD tumor metastasis. Mechanistically, LINC00943 was competitively bound with miR-1252-5p to enhance YWHAH expression. Moreover, LINC00943 silencing sponged miR-1252-5p to inhibit YWHAH, thereby retraining LAD cell malignant behaviors. In summary, LINC00943 facilitates LAD cell malignancy through sponging miR-1252-5p to upregulate YWHAH. LINC00943 is a novel lncRNA that serves as an oncogene and might be used as a prognostic biomarker for LAD.

Identification and validation of a novel cuproptosis-related stemness signature to predict prognosis and immune landscape in lung adenocarcinoma by integrating single-cell and bulk RNA-sequencing.

Cancer stem cells (CSCs) play vital roles in lung adenocarcinoma (LUAD) recurrence, metastasis, and drug resistance. Cuproptosis has provided a novel insight into the treatment of lung CSCs. However, there is a lack of knowledge regarding the cuproptosis-related genes combined with the stemness signature and their roles in the prognosis and immune landscape of LUAD. Cuproptosis-related stemness genes (CRSGs) were identified by integrating single-cell and bulk RNA-sequencing data in LUAD patients. Subsequently, cuproptosis-related stemness subtypes were classified using consensus clustering analysis, and a prognostic signature was constructed by univariate and least absolute shrinkage operator (LASSO) Cox regression. The association between signature with immune infiltration, immunotherapy, and stemness features was also investigated. Finally, the expression of CRSGs and the functional roles of target gene were validated in vitro. We identified six CRSGs that were mainly expressed in epithelial and myeloid cells. Three distinct cuproptosis-related stemness subtypes were identified and associated with the immune infiltration and immunotherapy response. Furthermore, a prognostic signature was constructed to predict the overall survival (OS) of LUAD patients based on eight differently expressed genes (DEGs) with cuproptosis-related stemness signature (KLF4, SCGB3A1, COL1A1, SPP1, C4BPA, TSPAN7, CAV2, and CTHRC1) and confirmed in validation cohorts. We also developed an accurate nomogram to improve clinical applicability. Patients in the high-risk group showed worse OS with lower levels of immune cell infiltration and higher stemness features. Ultimately, further cellular experiments were performed to verify the expression of CRSGs and prognostic DEGs and demonstrate that SPP1 could affect the proliferation, migration, and stemness of LUAD cells. This study developed a novel cuproptosis-related stemness signature that can be used to predict the prognosis and immune landscape of LUAD patients, and provided potential therapeutic targets for lung CSCs in the future.

Identification of RAC1 in promoting brain metastasis of lung adenocarcinoma using single-cell transcriptome sequencing

This study aims to give a new perspective to the biomarkers in the lung adenocarcinoma (LUAD) brain metastasis, pathways involved and potential therapeutics. We performed a comprehensive single-cell level transcriptomic analysis on one LUAD patient with circulating tumor cells (CTCs), primary tumor tissue and metastatic tumor tissue using scRNA-seq approach to identify metastasis related biomarkers. Further scRNA-seq were performed on 7 patients to validate the cancer metastatic hallmark. with single cells collected from either metastatic or primary LUAD tissues. Pathological and functional studies were also performed to evidence the critical role of RAC1 in the LUAD metastasis. Hallmark gene was verified based on immunohistochemistry staining, cytological experiment, survival information from The Cancer Genome Atlas (TCGA), and staining results from Human Protein Atlas (HPA) databases. PCA analysis revealed that CTCs were in the intermediate place between the metastatic group and primary group. In the unsupervised clustering analysis CTCs were closer to one of the metastatic tumor cells, implying heterogeneity of the metastatic tumor and origin of the CTCs were from metastatic site. Transitional phase related gene analysis identified RAC1 was enriched in metastatic tumor tissue (MTT) preferred gene set functioning as regulated cell death and apoptosis as well as promoted macromolecule organization. Compared with normal tissue, expression levels of RAC1 increased significantly in LUAD tissue based on HPA database. High expression of RAC1 predicts worse prognosis and higher-risk. EMT analysis identified the propensity of mesenchymal state in primary cells while epithelial signals were higher in the metastatic site. Functional clustering and pathway analyses suggested genes in RAC1 highly expressed cells played critical roles in adhesion, ECM and VEGF signaling pathways. Inhibition of RAC1 attenuates the proliferation, invasiveness and migration ability of lung cancer cells. Besides, through MRI T2WI results, we proved that RAC1 can promote brain metastasis in the RAC1-overexpressed H1975 cell burden nude mouse model. RAC1 and its mechanisms might promote drug design against LUAD brain metastasis.

JAC4 Inhibits EGFR-Driven Lung Adenocarcinoma Growth and Metastasis through CTBP1-Mediated JWA/AMPK/NEDD4L/EGFR Axis.

Lung adenocarcinoma (LUAD) is the most common lung cancer, with high mortality. As a tumor-suppressor gene, JWA plays an important role in blocking pan-tumor progression. JAC4, a small molecular-compound agonist, transcriptionally activates JWA expression both in vivo and in vitro. However, the direct target and the anticancer mechanism of JAC4 in LUAD have not been elucidated. Public transcriptome and proteome data sets were used to analyze the relationship between JWA expression and patient survival in LUAD. The anticancer activities of JAC4 were determined through in vitro and in vivo assays. The molecular mechanism of JAC4 was assessed by Western blot, quantitative real-time PCR (qRT-PCR), immunofluorescence (IF), ubiquitination assay, co-immunoprecipitation, and mass spectrometry (MS). Cellular thermal shift and molecule-docking assays were used for confirmation of the interactions between JAC4/CTBP1 and AMPK/NEDD4L. JWA was downregulated in LUAD tissues. Higher expression of JWA was associated with a better prognosis of LUAD. JAC4 inhibited LUAD cell proliferation and migration in both in-vitro and in-vivo models. Mechanistically, JAC4 increased the stability of NEDD4L through AMPK-mediated phosphorylation at Thr367. The WW domain of NEDD4L, an E3 ubiquitin ligase, interacted with EGFR, thus promoting ubiquitination at K716 and the subsequent degradation of EGFR. Importantly, the combination of JAC4 and AZD9191 synergistically inhibited the growth and metastasis of EGFR-mutant lung cancer in both subcutaneous and orthotopic NSCLC xenografts. Furthermore, direct binding of JAC4 to CTBP1 blocked nuclear translocation of CTBP1 and then removed its transcriptional suppression on the JWA gene. The small-molecule JWA agonist JAC4 plays a therapeutic role in EGFR-driven LUAD growth and metastasis through the CTBP1-mediated JWA/AMPK/NEDD4L/EGFR axis.

Mechanism of hypoxia-induced exosome circ_0051799 regulating the progression of lung adenocarcinoma.

This study attempted to investigate the effect of circ_0051799 on the immune microenvironment of lung adenocarcinoma (LUAD) and the relationship between circ_0051799 and exosomes. The number and morphology of exosomes were verified by nanoparticle tracking, transmission electron microscopy and western blotting. CCK8, EdU, Transwell and flow cytometry were used to verify the regulatory role of exosomes and circ_0051799 on tumor progression. Dual luciferase reporting and RNA immunoprecipitation were used to verify the targeted regulatory relationship between circ_0051799, miR-214-3p and IGF2BP3. WB was used to verify the role of the JAK/STAT pathway in circ_0051799 regulation. Ectopic tumor grafts and in situ models were used to validate invivo their role in regulating LUAD progression. Hypoxic environment could alter but does not alter its shape. Exosomes can participate in the regulation of macrophage polarization by circ_0051799. In vitro and invivo assays had shown that circ_0051799 could affect the proliferation and metastasis of LUAD through targeting miR-214-3p mediated IGF2BP3 regulated JAK/STAT pathway. This study found that hypoxia can affect LUAD process by promoting the regulation of macrophage polarization by exosome circ_0051799.

PHF14 enhances DNA methylation of SMAD7 gene to promote TGF-β-driven lung adenocarcinoma metastasis

Aberrant activation of TGF-β signaling plays a pivotal role in cancer metastasis and progression. However, molecular mechanisms underlying the dysregulation of TGF-β pathway remain to be understood. Here, we found that SMAD7, a direct downstream transcriptional target and also a key antagonist of TGF-β signaling, is transcriptionally suppressed in lung adenocarcinoma (LAD) due to DNA hypermethylation. We further identified that PHF14 binds DNMT3B and serves as a DNA CpG motif reader, recruiting DNMT3B to the SMAD7 gene locus, resulting in DNA methylation and transcriptional suppression of SMAD7. Our in vitro and in vivo experiments showed that PHF14 promotes metastasis through binding DNMT3B to suppress SMAD7 expression. Moreover, our data revealed that PHF14 expression correlates with lowered SMAD7 level and shorter survival of LAD patients, and importantly that SMAD7 methylation level of circulating tumor DNA (ctDNA) can potentially be used for prognosis prediction. Together, our present study illustrates a new epigenetic mechanism, mediated by PHF14 and DNMT3B, in the regulation of SMAD7 transcription and TGF-β-driven LAD metastasis, and suggests potential opportunities for LAD prognosis.

Tumor lineage-specific immune response in brain metastatic disease: opportunities for targeted immunotherapy regimen?

Metastases in the brain are the most severe and devastating complication of cancer. The incidence of brain metastasis is increasing. Therefore, the need of finding specific druggable targets for brain metastasis is demanding. The aim of this study was to compare the brain (immune) response to brain metastases of the most common tumor lineages, viz., lung adenocarcinoma and breast cancer. Targeted gene expression profiles of 11 brain metastasis of lung adenocarcinoma (BM-LUAD) were compared to 11 brain metastasis of breast cancer (BCBM) using NanoString nCounter PanCancer IO 360™ Panel. The most promising results were validated spatially using the novel GeoMx™ Digital Spatial Profiler (DSP) Technology. Additionally, Immune cell profiles and expression of drug targets were validated by multiplex immunohistochemistry. We found a more active immune response in BM-LUAD as compared to BCBM. In the BM-LUAD, 138 genes were upregulated as compared to BCBM (adj. p ≤ 0.05). Conversely, in BCBM 28 genes were upregulated (adj. p ≤ 0.05). Additionally, genes related to CD45 + cells, T cells, and cytotoxic T cells showed to be expressed higher in BM-LUAD compared to BCBM (adj. p = 0.01, adj. p = 0.023, adj. p = 0.023, respectively). The spatial quantification of the immune cells using the GeoMx DSP technique revealed the significantly higher quantification of CD14 and CD163 in tumor regions of BM-LUAD as compared to BCBM. Importantly, the immune checkpoint VISTA and IDO1 were identified as highly expressed in the BM-LUAD. Multiplex immunohistochemistry confirmed the finding and showed that VISTA is expressed mainly in BM-LUAD tumor cells, CD3 + cells, and to fewer levels in some microglial cells in BM-LUAD. This is the first report on differences in the brain immune response between metastatic tumors of different lineages. We found a far more extensive infiltration of immune cells in BM-LUAD as compared to BCBM. In addition, we found higher expression of VISTA and IDO1 in BM-LUAD. Taken together, targeted immune therapy should be considered to treat patients with BM-LUAD.