Lung Adenocarcinoma Cell Research Articles

Nicotine promotes M2 macrophage polarization through α5-nAChR/SOX2/CSF-1 axis in lung adenocarcinoma

α5-nicotinic acetylcholine receptor (α5-nAChR) plays a vital part in lung adenocarcinoma (LUAD). However, it is not comprehensively understood that how the α5-nAChR affects LUAD. Through diverse bioinformatics analyses and immunohistochemistry, the expressions of α5-nAChR and SOX2 as well as their relations were dissected. α5-nAChR regulated the differentiation of monocytes into M2 macrophages by targeting the STAT3/SOX2/CSF-1 signaling in the coculture system by western blotting and ChIP. α5-nAChR-mediated macrophage-mediated LUAD cell migration via SOX2/CSF-1 signaling in the cocultured medium. Correlations of α5-nAChR, SOX2 and M2 phenotype tumor-associated macrophages (TAMs) were validated in mouse LUAD models and clinical samples. α5-nAChR expression was connected to SOX2 expression, smoking and bad prognosis of LUAD among clinical samples. Nicotine-induced SOX2 expression was mediated by α5-nAChR via STAT3. Additionally, SOX2-mediated macrophage colony-stimulating factor (CSF-1) expression contributed to LUAD progression in vitro. Furthermore, α5-nAChR expression was strongly linked to pSTAT3, SOX2 and M2 macrophage marker CD206 expression and negatively correlated with M1 macrophage marker CD86 expression in vivo. It is indicated that M2 macrophages are mediated by the new α5-nAChR /SOX2/CSF-1 axis in nicotine-related LUAD, which is a potential therapeutic strategy for cancer.

MiR-195-5p inhibits cisplatin resistance in lung adenocarcinoma by regulating DNA damage via targeting E2F7.

Lung adenocarcinoma (LUAD) emerges as one of the most lethal malignant tumors worldwide. Platinum-based combination chemotherapy remains one of the main methods for patients with advanced LUAD. Due to the resistance, the effect of this chemotherapy was not satisfactory. Therefore, studying the mechanism of cisplatin (DDP) resistance is essential for promoting the effect of this therapeutic strategy. Therefore, this work sought to probe the impact of E2F Transcription Factor 7 (E2F7) on LUAD resistance and the molecular regulatory mechanism. The mRNA expression level of the target gene E2F7 in LUAD was predicted by bioinformatics analysis, and regulatory miRNA upstream of the target gene was identified. The mRNA and protein expression of E2F7 in LUAD cells was detected through quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot, respectively. The expression of miR-195-5p in LUAD cells was measured via qRT-PCR. E2F7 high and low expression groups underwent enrichment analysis by utilizing Gene Set Enrichment Analysis software. The targeting relationship of miR-195-5p and E2F7 was validated by conducting a dual-luciferase reporter assay. The cell viability was tested through cell counting kit-8. The cell cycle was examined by flow cytometry. DNA damage level was determined via Comet assay and Western blot assay. The findings indicated that the mRNA and protein levels of E2F7 were high in LUAD. MiR-195-5p was the regulatory miRNA upstream of E2F7, and lowly expressed in LUAD. The cell experiments suggested that E2F7 advanced the DDP resistance of LUAD cells by repressing DNA damage. Finally, the rescue assay manifested that miR-195-5p overexpression could abate inhibition of E2F7 overexpression on the DNA damage and the DDP sensitivity of LUAD cells. MiR-195-5p raised the DDP sensitivity of LUAD cells by advancing the DNA damage in LUAD cells via inhibition of E2F7.

HIF1A/PCDH7 axis mediates fatty acid synthesis and metabolism to inhibit lung adenocarcinoma anoikis.

Aberrantly expressed PCDH7 participates in the malignant progression of many cancers. PCDH7 has been newly discovered as a risk factor in lung cancer, but its functional study in lung adenocarcinoma (LUAD) has not been conducted yet. This study aimed to investigate the functional role of PCDH7 in LUAD. Bioinformatics analyzed the expression of PCDH7 and HIF1A in LUAD tissues, predicted the binding sites between the two, analyzed the clinicopathological relevance of PCDH7 and examined the pathway enrichment of PCDH7. Expression of PCDH7 and HIF1A in LUAD cells was analyzed by RT-qPCR. A nude mouse transplantation tumor model was constructed to analyze the effect of PCDH7 on tumor growth in vivo. The binding relationship between PCDH7 and HIF1A was confirmed by chromatin immunoprecipitation experiments and the dual-luciferase assay. Cell viability was detected with Cell Counting Kit-8. Triglyceride content and Caspase3 activity were measured using corresponding reagent kits. FASN and ACC1 expression was determined utilizing western blot. PCDH7 was highly expressed in LUAD and correlated with patients' overall survival time and N stage. In vitro and in vivo experiments confirmed that PCDH7 could promote LUAD growth and anoikis resistance. Moreover, overexpression of PCDH7 markedly increased the content of triglycerides in cells and promoted the expression of FASN and ACC1 proteins to inhibit LUAD cell anoikis. Cell rescue experiment confirmed that HIF1A activated PCDH7 to suppress LUAD anoikis by promoting fatty acid (FA) synthesis and metabolism. Our findings demonstrated that the HIF1A/PCDH7 axis suppressed LUAD anoikis by promoting FA synthesis and metabolism. The FA synthesis pathway might be a key pathway regulated by PCDH7 in LUAD anoikis.

ROR1-AS1: A Meaningful Long Noncoding RNA in Oncogenesis.

Long noncoding RNA (lncRNA) is a non-coding RNA with a length of more than 200 nucleotides, involved in multiple regulatory processes in vivo, and is related to the physiology and pathology of human diseases. An increasing number of experimental results suggest that when lncRNA is abnormally expressed, it results in the development of tumors. LncRNAs can be divided into five broad categories: sense, antisense, bidirectional, intronic, and intergenic. Studies have found that some antisense lncRNAs are involved in a variety of human tumorigenesis. The newly identified ROR1-AS1, which functions as an antisense RNA of ROR1, is located in the 1p31.3 region of the human genome. Recent studies have reported that abnormal expression of lncRNA ROR1-AS1 can affect cell growth, proliferation, invasion, and metastasis and increase oncogenesis and tumor spread, indicating lncRNA ROR1-AS1 as a promising target for many tumor biological therapies. In this study, the pathophysiology and molecular mechanism of ROR1-AS1 in various malignancies are discussed by retrieving the related literature. ROR1-AS1 is a cancer-associated lncRNA, and studies have found that it is either over- or underexpressed in multiple malignancies, including liver cancer, colon cancer, osteosarcoma, glioma, cervical cancer, bladder cancer, lung adenocarcinoma, and mantle cell lymphoma. Furthermore, it has been demonstrated that lncRNA ROR1-AS1 participates in proliferation, migration, invasion, and suppression of apoptosis of cancer cells. Furthermore, lncRNA ROR1-AS1 promotes the development of tumors by up-regulating or downregulating ROR1-AS1 conjugates and various pathways and miR-504, miR-4686, miR-670-3p, and miR-375 sponges, etc., suggesting that lncRNA ROR1-AS1 may be used as a marker in tumors or a potential therapeutic target for a variety of tumors.

BCAR1 facilitates the survival of lung adenocarcinoma cells by augmenting the unfolded protein response, autophagy, and the formation of vasculogenic mimicry.

Our objective was to elucidate the pivotal roles of BCAR1 in unfolded protein response (UPR), autophagy and vasculogenic mimicry (VM) formation, processes that essential for the metastasis of lung adenocarcinoma (LUAD) cells. The morphological assessment of endoplasmic reticulum (ER) status and autolysosomes in H1975 and H1299 LUAD cells following BCAR1 knockout (KO) was conducted using transmission electron microscope. The expression of markers and cellular functions related to the UPR, autophagy, and VM formation were examined in LUAD cells tissues. Additionally, proteomic analysis of LUAD cells was performed via mass spectrometry, and the pertinent signaling pathways were analyzed using bioinformatics tools. BCAR1-KO inhibited autophagy and UPR induced triggered starvation in LUAD cells. Cleaved-ATF6a-mediated UPR and subsequent autophagy, enhanced by BCAR1, were confirmed using the UPR stimulator and blocker. High BCAR1 expression, along with elevated UPR and autophagy, predicts poor prognosis in LUAD patients. BCAR1-KO reduced tube formation and VM markers expressions in LUAD cells. Additionally, BCAR1 expression positively correlated with VM formation in BALB/c-nu mice xenografts and LUAD patient tissues. BCAR1 promotes LUAD metastasis by enhancing cancer cell survival in nutrient-poor environments through ATF6-mediated UPR activation and autophagy. As BCAR1 induces VM formation, metastatic lesions eventually colonize. Thus, BCAR1 is a promising anti-metastasis target.

Elevated expression levels of the protein kinase DYRK1B induce mesenchymal features in A549 lung cancer cells

BackgroundThe protein kinase DYRK1B is a negative regulator of cell proliferation but has been found to be overexpressed in diverse human solid cancers. While DYRK1B is recognized to promote cell survival and adaption to stressful conditions, the consequences of elevated DYRK1B levels in cancer cells are largely uncharted.MethodsTo elucidate the role of DYRK1B in cancer cells, we established a A549 lung adenocarcinoma cell model featuring conditional overexpression of DYRK1B. This system was used to characterize the impact of heightened DYRK1B levels on gene expression and to monitor phenotypic and functional changes.ResultsA549 cells with induced overexpression of wild type DYRK1B acquired a mesenchymal cell morphology with diminished cell-cell contacts and a reorganization of the pericellular actin cytoskeleton into stress fibers. This transition was not observed in cells overexpressing a catalytically impaired DYRK1B variant. The phenotypic changes were associated with increased expression of the transcription factors SNAIL and SLUG, which are core regulators of epithelial mesenchymal transition (EMT). Further profiling of DYRK1B-overexpressing cells revealed transcriptional changes that are characteristic for the mesenchymal conversion of epithelial cells, including the upregulation of genes that are related to cancer cell invasion and metastasis. Functionally, DYRK1B overexpression enhanced the migratory capacity of A549 cells in a wound healing assay.ConclusionsThe present data identify DYRK1B as a regulator of phenotypic plasticity in A549 cells. Increased expression of DYRK1B induces mesenchymal traits in A549 lung adenocarcinoma cells.

Characterizing dynamic tumor-immune interactions in lung adenocarcinoma through orthotopic allograft modeling.

The major clinical challenge in lung cancer immunotherapy is drug resistance. Therefore, establishing efficient orthotopic lung cancer mouse models to explore the mechanisms of drug immunotherapy resistance is highly important. In this study, we generated multiple fluorescently labeled lung adenocarcinoma cell lines from agenetically engineered KPZ mice model. Orthotopic transplantation of the primary 1F3 cell line induced a strong immune response, causing many small tumors to disappear, but some tumors evaded the immune attack and eventually formed large tumors. Tumor microenvironment analysis demonstrated that M2 macrophages play key roles in the immune response. Further mechanistic studies revealed that the chemokine CCL7 promoted the infiltration of M2 macrophages to facilitate immune escape, thereby promoting tumor growth in the orthotopic mouse model. Moreover, CCL7 levels were elevated in human lung cancer biopsies and positively correlated with M2 macrophage infiltration, and high CCL7 levels predicted advanced pathological stage and poor survival in lung cancer patients. Overall, we established a visualized and orthotopic mouse model with fluorescently labeled cells to better dissect the tumor microenvironment of lung cancer and define the critical role of CCL7 in promoting M2 macrophage polarization and tumorigenesis, providing new preclinical tools and potential targets for lung cancer immunotherapy.

LNX1-AS2 as a Key Prognostic and Immunotherapy Response Biomarker for Lung Adenocarcinoma.

The role of LNX1 antisense RNA 2 (LNX1-AS2) in lung adenocarcinoma (LUAD) remains unclear. This study aimed to investigate the association between LNX1-AS2 and LUAD by employing bioinformatics analysis and experimental validation. Statistical analysis and database interrogation were utilized to assess correlations among LNX1-AS2 expression, clinical characteristics of LUAD patients, prognostic factors, regulatory networks, and immune infiltration. LNX1-AS2 expression in LUAD cell lines was quantified using quantitative real-time polymerase chain reaction (qRT-PCR). The study found significantly elevated levels of LNX1-AS2 expression in patients with LUAD. Furthermore, elevated LNX1-AS2 expression in LUAD patients did not significantly correlate with gender (p = 0.041) or race (p = 0.049). Importantly, high LNX1-AS2 expression levels were associated with poorer overall survival (OS, p = 0.042) and disease-specific survival (DSS, p = 0.040) in LUAD patients. Additionally, high LNX1-AS2 expression (p = 0.015) was independently correlated with OS in LUAD patients. The phenotype characterized by high LNX1-AS2 expression was also found to be enriched for asthma, allograft rejection, drug metabolism cytochrome P450, metabolism of xenobiotics by cytochrome P450, olfactory transduction, renin-angiotensin system, retinol metabolism, pentose and glucuronate interconversions, and porphyrin and chlorophyll metabolism. A significant correlation was identified between the expression levels of LNX1-AS2 and immune infiltration in the context of LUAD. Elevated expression of LNX1-AS2 was notably detected in LUAD cell lines as opposed to Beas-2B. A noteworthy relationship was established among increased LNX1-AS2 expression in LUAD patients, unfavorable prognosis, and heightened immune infiltration. These findings suggest that the LNX1-AS2 gene could serve as a valuable prognostic indicator for LUAD and a potential predictor of response to immunotherapy.

Comprehensive multi-omics analysis identifies chromatin regulator-related signatures and TFF1 as a therapeutic target in lung adenocarcinoma through a 429-combination machine learning approach

IntroductionLung cancer is a leading cause of cancer-related deaths, with its incidence continuing to rise. Chromatin remodeling, a crucial process in gene expression regulation, plays a significant role in the development and progression of malignant tumors. However, the role of chromatin regulators (CRs) in lung adenocarcinoma (LUAD) remains underexplored.MethodsThis study developed a chromatin regulator-related signature (CRRS) using a 429-combination machine learning approach to predict survival outcomes in LUAD patients. The CRRS model was validated across multiple independent datasets. We also investigated the impact of CRRS on the immune microenvironment, focusing on immune cell infiltration. To identify potential therapeutic targets, TFF1, a chromatin regulator, was knocked down using siRNA in LUAD cells. We assessed its impact through apoptosis analysis, proliferation assays, and in vivo tumor growth studies. Additional validation was performed using Ki67 expression and TUNEL assays.ResultsThe CRRS accurately predicted survival outcomes and was shown to modulate immune cell infiltration in the tumor microenvironment. High-risk patients demonstrated increased activity in cell cycle regulation and DNA repair pathways, along with distinct mutation profiles and immune responses compared to low-risk patients. TFF1 emerged as a key therapeutic target. Knockdown of TFF1 significantly inhibited LUAD cell proliferation, induced apoptosis, and suppressed in vivo tumor growth. Ki67 and TUNEL assays confirmed the role of TFF1 in regulating tumor growth and cell death.DiscussionThese findings highlight the potential of chromatin regulators in prognostic modeling and immune modulation in LUAD. TFF1 was identified as a promising therapeutic target, suggesting that targeting TFF1 could provide new treatment strategies. Further research is warranted to explore its full potential and therapeutic applicability.

The diagnosis value of dual-energy computed tomography (DECT) multi-parameter imaging in lung adenocarcinoma and squamous cell carcinoma.

Lung cancer continues to pose a serious risk to human health. With a high mortality rate, non-small cell lung cancer (NSCLC) is the major type of lung cancer, making up to 85% of all cases of lung cancer. Lung adenocarcinoma (AC), and lung squamous cell carcinoma (SC) are the two primary types of NSCLC. Determining the pathological type of NSCLC is important in establishing the most effective treatment method. Dual-energy computed tomography (DECT) multi-parameter imaging is an imaging technology that provides accurate and reliable disease diagnosis, and its uses are utilized for the combined diagnostic efficacy of AC and SC. The purpose of this study was to investigate the diagnostic value of spectral parameters of DECT in efficacy to AC and SC, and their combined diagnostic efficacy was also analyzed. We conducted a retrospective analysis of clinical and imaging data for 36 patients diagnosed with SC and 35 patients with AC. These patients underwent preoperative DECT chest scans, encompassing both arterial and venous phases, at our hospital from December 2020 to April 2022. The tumor diameter, water concentration (WC), iodine concentration (IC), normalized iodine concentration (NIC), Z effective (Zeff), and slope of the curve (K) in lesions were evaluated during two scanning phases in the two separate pathological types of lung cancers. The differences in parameters between these two types of lung cancers were statistically analyzed. In addition, receiver operating characteristic (ROC) curves were performed for these parameters to distinguish between SC and AC. In a univariate analysis involving 71 lung cancer patients, the results from Zeff, IC, NIC, and K from the AC's arterial and venous phase images were more elevated than those from the SC (P < 0.05). In contrast, the WC results were lower than those from SC (P < 0.05). The area under the ROC curve (AUC) for multi-parameter joint prediction typing was 0.831, with a corresponding sensitivity of 63.9% and specificity of 94.3%. It is possible to distinguish between central SC and AC using the spectrum characteristics of DECT-enhanced scanning (Zeff, IC, NIC, K, WC, and tumor diameter). Diagnostic effectiveness can be greatly improved when multiple variables are included.

VASN promotes the aggressive phenotype in ARID1A-deficient lung adenocarcinoma

Loss of ARID1A has been reported to drive the progression of lung adenocarcinoma, yet the underlying mechanism remains elusive. In this study, we performed secretome analysis to identify the key secreted proteins regulating lung adenocarcinoma progression. We showed that the VASN level was significantly elevated in the conditioned medium from ARID1A-depleted A549 and H1299 cells. Restoration of ARID1A in ARID1A-depleted lung adenocarcinoma cells prevented the upregulation and secretion of VASN. Clinical analysis demonstrated a negative correlation between ARID1A and VASN expression in ARID1A-mutated lung adenocarcinomas. The patients with ARID1A-mutated lung adenocarcinoma had significantly higher concentrations of serum VASN than healthy controls. Moreover, serum VASN concentrations were associated with TNM stage, lymph node metastasis, and overall survival of the patients with ARID1A-mutated lung adenocarcinoma. Functional studies indicated that VASN overexpression potentiated the proliferation, invasion, and tumorigenesis of lung adenocarcinoma cells. Antibody neutralization of VASN suppressed the aggressiveness of ARID1A-depleted lung adenocarcinoma cells both in vitro and in vivo. Addition of recombinant VASN protein promoted the proliferation and invasion of lung adenocarcinoma cells. Additionally, knockdown of Notch1 blocked the aggressive phenotype induced by recombinant VASN protein. In conclusion, our data uncover the role of VASN in mediating the progression of ARID1A-depleted lung adenocarcinoma and highlight VASN as a promising therapeutic target for this disease.

Oxidative phosphorylation related gene COA6 is a novel indicator for the prognosis and immune response in lung adenocarcinoma

Although the initial research focused on glycolysis, mitochondrial oxidative phosphorylation has become a major target of cancer cells. Cytochrome C oxidase assembly factor 6 (COA6) is a conserved assembly factor necessary for complex IV biogenesis. Nevertheless, the clinical predictive value of COA6, especially its correlation with immune cell infiltration in lung adenocarcinoma (LUAD), has not yet been elucidated. COA6 exhibited higher expression levels in LUAD cells and tumor tissues compared to normal tissues. Additionally, heightened COA6 expression was associated with reduced overall survival (OS) and advanced tumor stage. Apart from its role in mitochondrial respiratory processes, COA6 may be involved in the process of antigen binding, immunoglobulin receptor binding. Interestingly, we observed a positive correlation between COA6 expression and tumor mutational burden (TMB), as well as a significant association with decreased immune cell infiltration. COA6 was linked to resistance against gemcitabine and etoposide. We verified that COA6 was highly expressed in LUAD experimentally and cell proliferation was inhibited after COA6 knockdown. Thus, we conclude that the expression of COA6 was correlated with reduced immune cell infiltration. Additionally, COA6 functioned as a biomarker for drug sensitivity and the prognosis of lung adenocarcinoma.

Inhibition of JNK/STAT3/NF-KB pathway-mediated migration and clonal formation of lung adenocarcinoma A549 cells by daphnetin

ABSTRACT Daphnetin, a coumarin derivative isolated from Daphne odorifera, has anti-tumor effects. The MAPK, STAT3, and NF-κB signaling pathways are closely related to the pathogenesis of lung cancer. To investigate the effect of daphnetin on anti-lung adenocarcinoma A549 cells and its mechanism. The anti-tumor effects of daphnetin on the proliferation, clone formation, migration, and invasion of A549 lung adenocarcinoma cells were investigated. The results showed that daphnetin inhibited the proliferation, colony formation, migration, and invasion of A549 cells through the MAPK/STAT3/NF-KB pathway, and mainly inhibited the clonal formation and migration of A549 cells through the JNK pathway. These results provide a new research direction and theoretical basis for the use of daphnetin in the inhibition of lung adenocarcinoma.

Epigenetic Regulation of CXC Chemokine Expression by Environmental Electrophiles Through DNA Methyltransferase Inhibition

Ubiquitously distributed environmental electrophiles covalently modify DNA and proteins, potentially leading to adverse health effects. However, the impacts of specific electrophiles on target proteins and their physiological roles remain largely unknown. In the present study, we focused on DNA methylation, which regulates gene expression and physiological responses. A total of 45 environmental electrophiles were screened for inhibitory effects on the activity of DNA methyltransferase 3B (DNMT3B), a key enzyme in DNA methylation, and four compounds were identified. We focused on 1,2-naphthoquinone (1,2-NQ), an air pollutant whose toxicity has been reported previously. Interestingly, we found that 1,2-NQ modified multiple lysine and histidine residues in DNMT3B, one of which was near the active site in DNMT3B. It was found that 1,2-NQ altered gene expression and evoked inflammatory responses in lung adenocarcinoma cell lines. Furthermore, we found that 1,2-NQ upregulated CXCL8 expression through DNA demethylation of the distal enhancer and promoted cancer cell growth. Our study reveals novel mechanisms of epigenetic regulation by environmental electrophiles through the inhibition of DNMT3B activity and suggests their physiological impact.

BATF-Activated AIM2 Mediates Immune Escape in Lung Adenocarcinoma by Regulating PD-L1

Introduction: Immunotherapy has demonstrated encouraging outcomes in tackling lung adenocarcinoma (LUAD), but immune escape may bring negative impacts. Only a single study has demonstrated the function of AIM2 in LUAD and reported that NF-κB and STAT1 are the chief transcription factors, this study is designed to analyze the role of AIM2 and examine the transcription factor, BATF in LUAD immunotherapy. Methods: Bioinformatics methods to analyze the expression and binding sites of AIM2 and BATF in LUAD, as well as the correlation between AIM2 and PD-L1. Dual-luciferase and chromatin immunoprecipitation assays were used to verify the binding of AIM2 and BATF. qRT-PCR and Western blot assayed expression of AIM2, BATF, and PD-L1 in LUAD. MTT measured cell viability, flow cytometry detected cell apoptosis, cytotoxicity assays measured the toxicity of CD8+ T cells to cancer cells, and enzyme-linked immunosorbent assay measured the expression of related cytokines. Immunohistochemistry detected the protein expression levels of AIM2, BATF, PD-L1, and CD8 in tumor tissue. Results: AIM2 and BATF were both highly expressed in LUAD, and there was a targeted binding relationship. BATF promoted LUAD cell proliferation and inhibited apoptosis by affecting AIM2 expression. The downregulation of AIM2 and PD-L1 expression inhibited PD-L1 and activated CD8+ T cells. The rescue experiment manifested that increased BATF weakened repression of AIM2 silencing on LUAD tumor immune escape in vitro and in vivo. Conclusion: BATF promoted AIM2 expression, upregulated PD-L1, inhibited CD8+ T cell activity, and ultimately led to immune escape in LUAD. Our research uncovered an innovative outlook on the intricate regulation of immune checkpoint molecules and proposed a new approach to target the BATF/AIM2 axis in tumor immunotherapy.

Hsa_circ_0001492 regulates the hsa-miR-145-5p/ovarian carcinoma immunoreactive antigen domain 2 axis to promote the progression of lung adenocarcinoma.

Circular RNA (circRNA) has been proven to be a key regulator in a range of tumor illnesses, such as lung adenocarcinoma (LUAD); however, the regulatory mechanisms of circRNA remain unclear. In this study, circRNA (hsa_circ_0001492) in LUAD was examined for its regulatory and functional potential. qRT-PCR was used to assess the hsa_circ_0001492 level in LUAD. The RNAse R digestion test was employed to isolate hsa_circ_0001492. The primary location of hsa_circ_0001492 enrichment in LUAD cells was identified through a nucleoplasmic separation test. LUAD cell migration, proliferation, and spherogenicity were examined using wound healing, transwell, EdU, and cell spherogenicity assays. The association between miR-145-5p and hsa_circ_0001492/ovarian carcinoma immunoreactive antigen domain 2 (OCIAD2) was validated using a dual luciferase experiment. The interaction between sh-hsa_circ_0001492 and miR-145-5p was confirmed through an RNA pull-down assay. The effects of hsa_circ_0001492, miR-145-5p, and OCIAD2 on LUAD tumor development were examined using xenograft mouse models and immunohistochemistry tests. Results showed a higher amount of hsa_circ_0001492 in LUAD. The cytoplasm of LUAD cells was observed in the area where hsa_circ_0001492 mainly accumulated; hsa_circ_0001492 enhanced LUAD cell migration, proliferation, and sphere-forming ability. MiR-145-5p and OCIAD2 were identified as targets of hsa_circ_0001492 and miR-145-5p, respectively. The level of OCIAD2 was increased by hsa_circ_0001492 through targeted binding to miR-145-5p. In nude mice, tumor growth was inhibited by silencing hsa_circ_0001492, while knockdown of miR-145-5p and overexpression of OCIAD2 promoted the growth of LUAD tumors. In conclusion, hsa_circ_0001492 regulates the hsa-miR-145-5p/OCIAD2 axis to promote the progression of LUAD, and could be a useful target for the diagnosis and treatment of LUAD.

Genetic profile of ferroptosis in non-small cell lung carcinoma and pharmaceutical options for ferroptosis induction.

Lung cancer (LC) is the leading cause of cancer-related deaths and the second most commonly diagnosed malignancy worldwide. Lung adenocarcinoma (LUAD) and lung squamous cell LC (LUSCC) are the most common subtypes of non-small cell LC (NSCLC). Early diagnosis of LC can be challenging due to a lack of biomarkers. The overall survival (OS) of patients with NSCLC is still poor despite the enormous efforts that have been made to develop novel treatments. Understanding fundamental molecular and genetic mechanisms is necessary to develop new therapeutic approaches for NSCLC. A recently identified type of programmed cell death known as ferroptosis is one potential approach. Ferroptosis causes oxidative damage and the death of cancerous cells by peroxidizing unsaturated phospholipids and accumulating reactive oxygen species (ROS) in an iron-dependent manner. Ferroptosis-related gene (FRG) signatures have recently been evaluated for their ability to predict patient OS and prognosis. These analyses show FRGs are involved in cancer progression, and may serve as promising biomarkers for tumor diagnosis and therapy. Moreover, we summarize the current pharmaceutical options of ferroptosis induction and their underlying molecular mechanism in LC. Therefore, this review aims to provide a comprehensive summary of FRG-based prognostic models, their associated metabolic and signaling pathways, and promising therapeutic options for ferroptosis induction in NSCLC.

Identification of a Novel Signature Based on Ferritinophagy-Related Genes to Predict Prognosis in Lung Adenocarcinoma: Focus on AHNAK2

Background: Lung adenocarcinoma (LUAD) accounts for over 40% of all non-small cell lung cancer (NSCLC) cases and continues to be difficult to treat despite advancements in diagnostics and therapies. Ferritinophagy, a newly recognized autophagy process linked to ferroptosis, has been associated with LUAD development. Recent studies have shown a dysregulation of genes related to ferritinophagy in LUAD, indicating its potential as a therapeutic target. Methods: We constructed a predictive model using seven genes associated with ferritinophagy. The model’s accuracy was evaluated across three independent gene expression datasets. We analyzed the biological functions, immune environment, mutations, and drug sensitivities in groups with high and low risk. Utilizing a single-cell sequencing (scRNA-seq) dataset, we confirmed the expression of the model genes and identified a subtype of epithelial cells expressing AHNAK2. We further investigated the impact of the ferritinophagy-related gene AHNAK2 on LUAD cell proliferation, invasion, migration, and ferroptosis in vitro. Results: Our prediction model, comprising seven genes (AHNAK2, ARNTL2, CD27, LTB, SLC15A1, SLC2A1, and SYT1), has shown potential in predicting the prognosis of individuals diagnosed with LUAD. Notably, AHNAK2 impedes ferroptosis, promoting LUAD progression in vitro. Conclusions: Our research suggests that ferritinophagy-associated genes are promising prognostic markers for LUAD and lay the groundwork for further exploration of ferritinophagy’s role in LUAD. Furthermore, we present AHNAK2 as a novel regulator of ferroptosis, which requires further investigation to understand its mechanism.

A-to-I-edited miR-1251-5p restrains tumor growth and metastasis in lung adenocarcinoma through regulating TCF7-mediated Wnt signaling pathway

BackgroundRNA editing from A (adenine nucleotide) to I (hypoxanthine nucleotide) mediated by ADARs has attracted more and more attention as an important post-transcriptional processing method. This research investigates the regulatory mechanism of A-to-I-edited miR-1251-5p in lung adenocarcinoma (LUAD).MethodsRT-qPCR, Western blot, and Immunohistochemistry assays measured miRNA and gene expression. Colony formation, CCK-8, Transwell, Wound-healing, and Animal assays were used to determine MiRNA function. Luciferase reporter assay tested miRNA downstream target.ResultsADAR1 increased the A-to-I editing efficiency of miR-1251-5p in LUAD cells. In comparison to the unedited wild-type form, edited miR-1251-5p exhibits a marked inhibition of tumor growth and metastasis in LUAD. Moreover, knockdown of TCF7 also exhibits tumor inhibitory effect in LUAD development. Mechanically, edited miR-1251-5p inactivates Wnt signaling pathway by inhibiting TCF7, MYC, and CCND1 expression.ConclusionCompared with original miR-1251-5p, edited miR-1251-5p has stronger anti-cancer effect on LUAD development through inactivating Wnt signaling pathway by inhibiting TCF7.

UBE2C promotes LUAD progression by ubiquitin-dependent degradation of p53 to inactivate the p53/p21 signaling pathway

Lung adenocarcinoma (LUAD) is one of the greatest causes of cancer death worldwide. As a novel potential tumor biomarker, ubiquitin-conjugating enzyme E2C (UBE2C) is a critical factor during the onset and development of human cancers. However, the mechanisms of UBE2C in LUAD are not well understood. In this study, increased expression level of UBE2C was observed in LUAD tumor tissues. High LUAD level portended a worse prognosis of LUAD patients. Down-regulation of UBE2C attenuated the cell proliferation and cycle, migration, and invasion. Consistently, the tumorigenic capacity of LUAD cells in nude mice was significantly suppressed by the knockdown of UBE2C. Knockdown of UBE2C inhibited the degradation of p53 protein via an ubiquitin-proteasome pathway, thereby increasing p53 and p21 protein expression. Moreover, the inhibition of LUAD cell malignant phenotypes caused by UBE2C knockdown was attenuated on account of the inactivation of p53/p21 signaling pathway. In conclusion, UBE2C facilitates cell malignant behaviour in LUAD by ubiquitin-dependent degradation of p53 to suppress the p53/p21 signaling pathway. UBE2C is potentially developed as a therapeutic target for patients with LUAD.