Lung Adenocarcinoma Cell Line Research Articles

Identification of a transcription factor‑cyclin family genes network in lung adenocarcinoma through bioinformatics analysis and validation through RT‑qPCR.

Lung adenocarcinoma (LUAD) is the predominant pathological subtype of lung cancer, which is the most prevalent and lethal malignancy worldwide. Cyclins have been reported to regulate the physiology of various types of tumors by controlling cell cycle progression. However, the key roles and regulatory networks associated with the majority of the cyclin family members in LUAD remain unclear. In total, 556 differentially expressed genes were screened from the GSE33532, GSE40791 and GSE19188 mRNA microarray datasets by R software. Subsequently, protein-protein interaction network containing 499 nodes and 4,311 edges, in addition to a significant module containing 76 nodes and 2,631 edges, were extracted through the MCODE plug-in of Cytoscape. A total of four cyclin family genes [cyclin (CCNA2, CCNB1, CCNB2 and CCNE2] were then found in this module. Further co-expression analysis and associated gene prediction revealed forkhead box M1 (FOXM1), the common transcription factor of CCNB2, CCNB1 and CCNA2. In addition, using GEPIA database, it was found that the high expression of these four genes were simultaneously associated with poorer prognosis in patients with LUAD. Experimentally, it was proved that these four hub genes were highly expressed in LUAD cell lines (Beas-2B and H1299) and LUAD tissues through qPCR, western blot analysis and immunohistochemical studies. The diagnostic value of these 4 hub genes in LUAD was analyzed by logistic regression, CCNA2 was deleted, following which a nomogram diagnostic model was constructed accordingly. The area under the curve values of CCNB1, CCNB2 and FOXM1 diagnostic models were calculated to be 0.92, 0.91 and 0.96 in the training set (Combined dataset of GSE33532, GSE40791 and GSE19188) and two validation sets (GSE10072 and GSE75037), respectively. To conclude, data from the present study suggested that the FOXM1/cyclin (CCNA2, CCNB1 and/or CCNB2) axis may serve a regulatory role in the development and prognosis of LUAD. Specifically, CCNB1, CCNB2 and FOXM1 have potential as diagnostic markers and/or therapeutic targets for LUAD treatment.

SMEK1 promotes lung adenocarcinoma proliferation and invasion by activating Wnt/β-catenin signaling pathway.

SMEK1, also known as PP4R3α, the regulatory subunit 3α of serine and threonine phosphatase PP4, participates in diversely critical biological processes such as the integration of centromere, deacetylation of histones, asymmetric divisions of neuroblast, and other crucial cellular activities. SMEK1 was formerly reported to play a part in carcinogenesis. This study aims to reveal the role of SMEK1 in lung adenocarcinoma and the underlying molecular mechanism. Using immunohistochemical (IHC) staining, the protein level of SMEK1 in lung adenocarcinoma and adjacent non-tumor tissue was detected. The functional role of SMEK1 in cell proliferation and invasion was explored using cell counting kit-8 and Transwell assay, respectively. Xenograft tumor experiment was used to investigate the effect of SMEK1 on tumor growth in vivo. The alteration of Wnt/β-catenin signaling pathway was detected by Western blotting, quantitative PCR, and dual-luciferase reporter assays. SMEK1 was highly expressed at the protein level in lung adenocarcinoma compared to the adjacent non-tumor tissue. In vitro, suppression of SMEK1 significantly decreased the proliferation, migration, and invasion of lung adenocarcinoma cell lines, while overexpression of SMEK1 enhanced above abilities. The xenograft model demonstrated that down-regulation of SMEK1 significantly inhibited tumor growth in vivo. In addition, we found that SMEK1 could positively regulate Wnt/β-catenin signaling in lung adenocarcinoma cell lines. SMEK1 exerts a cancer-promoting effect in lung adenocarcinoma by activating Wnt/β-catenin signaling.

Classification and characterization of alternative promoters in 26 lung adenocarcinoma cell lines.

Genome-wide landscape of alternative promoter use remains unknown. We determined expression profiles of promoters in 26 lung adenocarcinoma cell lines using the transcriptional start site-sequencing data and proposed an index 'canonical promoter usage' to quantify the diversity of alternative promoter usage. Transcriptional start site-sequencing and other datasets were obtained from the DataBase of Transcriptional Start Sites. Transcriptional start site-sequencing read clusters were mapped onto RefGene to determine the promoters. Commonly used promoters were designated as canonical promoters. The sequence logos, CpG islands, DNA methylation and histone modifications of canonical and non-canonical promoters were examined. Canonical promoter usage was calculated by dividing 'read counts of a canonical promoter' by 'read counts of all the units of promoters' on each gene. The expressed genes were subjected to hierarchical clustering according to their canonical promoter usage. Among 104 455 promoters for 14 297 genes, 8659 canonical and 68 197 non-canonical promoters were identified. Corresponding to higher expression, canonical promoters showed core promoter sequences, higher CpG island positivity, less DNA methylation and higher transcription-promoting histone modifications. Gene ontology enrichment analysis revealed that the clusters with lower canonical promoter usage were related to signalling pathways, whereas clusters of tightly regulated genes with higher canonical promoter usage were related to housekeeping genes. Canonical promoters were regulated by conventional transcriptional machinery, while non-canonical promoters would be targets of 'leaky' expression. Further investigation is warranted to analyse the correlation between alternative promoter usage and biological characteristics contributing to carcinogenesis.

Abstract A003: Enhancer amplification defines lineage addiction in human lung adenocarcinoma

Abstract Lung cancer is the most common cause of death from cancer worldwide, and lung adenocarcinoma (LUAD) is the most common subtype of lung cancer. NKX2-1 (also known as TTF-1, TITF-1) is a lineage defining transcription factor throughout normal lung development. In LUAD, NKX2-1 is a highly specific and sensitive marker for 85-90% of both primary and metastatic LUADs. We and others identified NKX2-1 as the most significantly amplified gene in LUAD. NKX2-1 is amplified as the earliest stages of LUAD development, and NKX2-1 amplification is a truncal event in multi-region LUAD evolution. Despite strong evidence for an oncogenic role for NKX2-1, little is known about the mechanisms of NKX2-1 activation, or how its oncogenic regulation drives LUAD. Here, we identify recurrent focal amplification targeting a super-enhancer (SE) of NKX2-1 as a driving event in LUAD. Using epigenomic data from LUAD cell lines and primary samples, we identify this region as a lineage super-enhancer that is specifically active in NKX2-1(+) cell lines and patients. Notably, this region is co-amplified with NKX2-1 in 95.9% (143/149) of NKX2-1-amplified samples, suggesting this region is a hallmark of NKX2-1 activation, through focal or co-amplification with NKX2-1. Using endogenous ChIP-seq and exogenous luciferase assays, we show the enhancer activity of the NKX2-1 SE is comprised of three constituent enhancers, and map the transcriptional activity of the strongest enhancer to individual binding motifs for AP-1 and ETS. Using CRISPR inhibition (CRISPRi) and CRISPR activation (CRISPRa) in LUAD cell lines expressing high or low levels of NKX2-1, we show that activity of the NKX2-1 SE defines endogenous NKX2-1 expression. Using genome-wide shRNA and CRISPR screens, we identify a NKX2-1 dependency in NKX2-1 positive LUAD cell lines, and validate this dependency in clonogenic and proliferation assays. Using RNA sequencing (RNA-seq), we find that NKX2-1 knockdown activates an epithelial-mesenchymal transition (EMT) gene signature and downregulates an alveolar differentiation signature, including critical markers of LUAD differentiation, such as NAPSA, LMO3, and SLC34A2. Using a global clustering approach to CCLE RNA-seq of LUAD cell lines, we find that NKX2-1(+) LUAD cell lines cluster apart from NKX2-1(–), and that NKX2-1 knockdown regulates the majority (57/97) of genes that distinguish NKX2-1(+) LUADs. Similarly, we find that global clustering of H3K27ac ChIP-seq in LUAD cell lines separates NKX2-1(+) cells, and identify enhancers that are uniquely active NKX2-1(+) LUAD cell lines. We find these enhancers are bound and activated by NKX2-1, regulating genes we identified above such as NAPSA and LMO3. Our data demonstrates that enhancer amplification is a hallmark of oncogenic NKX2-1 activation in LUAD, through which NKX2-1 drives a lineage addicted state and oncogenic cell proliferation. This suggests that NKX2-1 is a critical defining oncogene for LUAD, and that targeting of NKX2-1 or its enhancer may suppress LUAD. Citation Format: John L. Pulice, Matthew Meyerson. Enhancer amplification defines lineage addiction in human lung adenocarcinoma. [abstract]. In: Proceedings of the AACR Special Conference: Cancer Epigenomics; 2022 Oct 6-8; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_2):Abstract nr A003.

Exploration of Chemopreventive Potential of Linalool in Targeting Lung Cancer Biomarkers.

Phytochemicals are used to treat lung cancer in contemporary and traditional medicine. The limitations of known chemotherapeutic drugs such as non-specificity, resistance, and toxicity restrict their use for lung cancer treatment. Therefore, the search for target-specific novel entities is required continuously. Linalool, a monoterpene alcohol that possesses antiviral, anti-inflammatory, and antibacterial properties, is present in sweet basil, laurel, jasmine, rosewood, and lavender. Previous reports revealed its anticancer potential against colon, breast, and liver cancer. In this study, linalool's efficacy in targeting biomarkers associated with different lung cancer stages has been investigated. The in silico molecular docking analysis was used to explore drug-receptor interaction, and further, linalools cytotoxicity potential was evaluated on lung adenocarcinoma cell line (A549). The toxicity profiling of linalool was done by ADMET analysis. In the results, Linalool revealed an excellent binding affinity with the selected targets. It showed the highest interaction with BRAF with the binding energy of -5.6 kcal/mol. Furthermore, it successfully interacts within the binding pocket of BRAF, similar to its inhibitor (Sorafenib). In MTT analysis, linalool significantly reduces the percent viability IC30 474.94 ± 43.12, 379.33 ± 49.5, and 183.77 ± 66.7 μM in A549 cell lines for 24, 48, and 72 h, respectively. These results concluded that linalool possesses chemopreventive potential against lung cancer by interacting or modulating selected biomarkers associated with a lung cancer diagnosis, progression, and proliferation.

Decreased Expression of a Novel lncRNA FAM181A-AS1 is Associated with Poor Prognosis and Immune Infiltration in Lung Adenocarcinoma.

There is no clear information regarding the role of FAM181A antisense RNA 1 (FAM181A-AS1) in lung adenocarcinoma (LUAD). We explored the relationship between FAM181A-AS1 and LUAD using bioinformatics analysis and experimental validation in this study. Statistics and databases were used to evaluate the relationship between clinical features in LUAD patients and FAM181A-AS1 expression, prognostic factors, regulation network, and immune infiltration of FAM181A-AS1 in function. LUAD cell lines were tested for FAM181A-AS1 expression using qRT-PCR. FAM181A-AS1 showed significantly low expression in LUAD patients. Low FAM181A-AS1 expression predicted a poorer overall survival (OS) (HR: 0.66; 95% CI: 0.49-0.88; P=0.005) and disease specific survival (DSS) (HR: 0.64; 95% CI: 0.44-0.92; P=0.017) of LUAD patients. There was also an independent correlation between low FAM181A-AS1 expression (HR: 0.547; 95% CI: 0.350-0.857; P=0.008) and OS in LUAD patients. The FAM181A-AS1 high-expression phenotype was differentially enriched for M phase, cellular senescence, cell cycle checkpoints, chromatin modifying enzymes, ESR-mediated signaling, DNA repair, G2/M checkpoints, HCMV infection, and DNA double-strand break repair. A correlation was found between the expression of FAM181A-AS1 and immune infiltrating cells. A significant decrease in FAM181A-AS1 expression was observed in LUAD cell lines compared to Beas-2B. There was a significant association between low FAM181A-AS1 expression in LUAD patients and poor survival and immune infiltration. The FAM181A-AS1 gene may provide a useful biomarker for LUAD prognosis and immunotherapy response.

Correlation between oncogene integrator complex subunit 7 and a poor prognosis in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is one of the most common types of cancer worldwide with high incidence and mortality rates. The integrator complex subunit 7 (INTS7) encodes a subunit of the integrator complex that mediates small-nuclear ribonucleic acid (RNA) processing and has been shown to be associated with RNA polymerase II. However, the clinical significance of INTS7 in LUAD is still not clear and needs to be investigated. The single-cell sequencing of a publicly available data set was conducted to compare the expression levels and percentages of INTS7 in lung malignant cells at different classifications and stages. Further, 33 cancer types from The Cancer Genome Atlas (TCGA) database were analyzed, protein-protein interaction (PPI) networks were constructed, and functional annotations were undertaken for the INTS7 gene. INTS7 small-interfering RNAs were transfected into LUAD cell lines, and cell biological behaviors, such as migration, invasion, apoptosis and proliferation capacity, were then examined. We found that the expression of INTS7 was significantly more upregulated in the LUAD tissues than the adjacent normal tissues. Increased INTS7 messenger RNA expression was correlated with TNM (tumor node metastasis classification) stage and gender in LUAD patients. Further, the Kaplan-Meier survival analysis indicated that LUAD patients with high INTS7 expression levels had a worse prognosis than those with low INTS7 expression levels. Finally, we found that silencing INTS7 inhibited LUAD cell viability and invasion in vitro. These results suggest that INTS7 can be used as a potential therapy target and prognostic marker for LUAD. Further, INTS7 may aggravate migration and invasion, induce the proliferation, and attenuate the apoptosis capacity of cells in LUAD.

MiR-202-3p inhibits the proliferation and metastasis of lung adenocarcinoma cells by targeting RRM2.

Lung adenocarcinoma (LUAD) is the most common type of lung cancer, and its pathogenesis is still unclear. The present study aimed to investigate the role of miR-202-3p and its downstream target gene, ribonucleotide reductase regulatory subunit M2 (RRM2), in the occurrence and development of LUAD and elucidate the correlation between RRM2 and the clinicopathological stage and prognosis of LUAD. The expression of miR-202-3p was analyzed using the CancerMIRNome database and quantitative polymerase chain reaction (qPCR). The effects of miR-202-3p and RRM2 on the proliferation, migration, and invasion of A549 cells were analyzed. A dual luciferase reporter assay was used to verify the targeting of miR-202-3p and RRM2. Additionally, the correlation between RRM2 expression and clinicopathology was analyzed. (I) MiR-202-3p was lowly expressed in LUAD and the LUAD cell lines. qPCR confirmed that microRNA (miRNA) transfection was effective and sufficient for subsequent experiments. (II) MiR-202-3p inhibited the proliferation, invasion, and migration of LUAD cells. (III) There was a targeting relationship between miR-202-3p and RRM2, and miR-202-3p affected the expression of the RRM2 protein. RRM2 was highly expressed in lung cancer tissue. (IV) RRM2 was associated with the clinicopathological staging of lung cancer. The prognosis of patients with low RRM2 expression was better, and the prognostic sensitivity of RRM2 to lung cancer was high. RRM2 may exert its effects via the Notch pathway. (V) Si-RRM2 inhibited the expression of the RRM2 protein. RRM2 promoted the proliferation, migration, and invasion of LUAD cells. A miR-202-3p inhibitor restored the inhibitory effect of si-RRM2 on LUAD cells. MiR-202-3p was lowly expressed in lung cancer tissue. MiR-202-3p overexpression inhibited the proliferation and metastasis of lung cancer cells. RRM2 was highly expressed in lung cancer tissue and promoted the proliferation and metastasis of lung cancer cells. MiR-202-3p targeted and inhibited RRM2, thereby reducing the proliferation and metastasis of LUAD cells. LUAD patients with low RRM2 expression had a better prognosis, and the expression level of RRM2 was correlated with the clinical characteristics of lung cancer patients.

The roles of CPSF6 in proliferation, apoptosis and tumorigenicity of lung adenocarcinoma.

Cleavage and polyadenylation specific factor 6 (CPSF6), a member of serine/arginine-rich protein family, is implicated in HIV-1-infection and replication. Overexpression of CPSF6 predicts poor prognostic outcomes of breast cancer. However, the expression and possible function of CPSF6 in lung adenocarcinoma (LUAD) still needs to be explored. Here, we found that CPSF6 is significantly higher expressed in tumor tissues than normal tissues in multiple cancer types. Besides, CPSF6 plays a significant risky role in LUAD that is associated with overall survival (HR=1.337, P=0.051) and disease-specific survival (HR=1.4739, P=0.042). CPSF6 mRNA was up-regulated in LUAD tissues by analyzing publicly available datasets from Gene Expression Omnibus (GEO). Further survival analysis on The Cancer Genome Atlas (TCGA) dataset suggested a close correlation between CPSF6 expression and overall survival, and disease-free survival of LUAD patients. Inhibition of CPSF6 expression by lentivirus-mediated RNA interference (RNAi) in two LUAD cell lines (A549 and NCH-H1299) caused a significant reduction in cell proliferation, colony formation and a notable induction in apoptotic rate. CPSF6 knockdown in xenograft tumors inhibited LUAD cell growth in vivo. Moreover, we identified differentially expressed genes with CPSF6 inhibition by Microarray analysis, and pathway analyses revealed that CPSF6 knockdown resulted in the dysregulation of the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway. Collectively, our results are the first to demonstrate that CPSF6 functions as an oncoprotein by regulating cancer-related pathways in LUAD.

Study of Drug Resistance in Chemotherapy Induced by Extracellular Vesicles on a Microchip.

Drug resistance in chemotherapy has been greatly challenging for cancer treatment. Research has revealed that extracellular vesicles (EVs) secreted by drug-resistant cells could induce chemoresistance in susceptible cells. However, there are few ways to give direct evidence of it. Herein, we have proposed a microchip-based system to study the drug resistance of a wild-type human lung adenocarcinoma cell line (A549/WT) induced by EVs derived from A549/DDP cells that are resistant to cisplatin (DDP) inherently. EVs derived from A549/DDP were proved to be the crucial factor that enhanced the resistance of A549/WT to DDP through live and dead cell staining, cell viability testing, and immunofluorescence of P-glycoprotein in the off-chip assay. Then, it was further validated that drug resistance of A549/WT cells to DDP significantly increased after being cocultured with A549/DDP cells within 96 h in the on-chip assay. These findings proved that the change of A549/WT drug resistance was caused by intercellular interaction, which was mainly mediated by EVs. In addition, we successfully reversed the EV-induced drug resistance of A549/WT cells by combining DDP and metformin, a hypoglycemic drug with low cytotoxicity when used alone. This microchip system provides a novel tool that has great potential for the investigation of cell interaction, drug resistance, and the tumor microenvironment in fundamental and clinical medicine.

Chemical Profiling, Antiproliferative and Antimigratory Capacity of Haberlea rhodopensis Extracts in an In Vitro Platform of Various Human Cancer Cell Lines.

Haberlea rhodopensis is a Balkan endemic plant that belongs to the Gesneriaceae family, and is believed to have medicinal use and health-promoting properties. This study aimed to (i) prepare aqueous (HAE) and ethanolic (HEE) extracts from the leaves of H. rhodopensis from in vitro propagated plants, (ii) screen for their potential antiproliferative and antimigratory activities, and (iii) chemically characterize both HAE and HEE by identifying compounds which may contribute to their observed bioactivity thereby further supporting their potential use in biomedical applications. The antiproliferative activity of both extracts was assessed against six human cancer cell lines by employing the sulforhodamine-B (SRB) assay. HEE was found to be more potent in inhibiting cancer cell growth as compared to HAE. Therefore, HEE's antimigratory effects were further studied in hepatocellular carcinoma (HepG2) and non-small cell lung adenocarcinoma (A459) cell lines as they were among the most sensitive ones to its antiproliferative activity. HEE was found to exert significant antimigratory concentration-dependent effects in both cell lines assessed with the wound healing assay. Chemical characterization by UPLC-MS/MS analysis identified that HEE contains higher levels of flavonoids, phenolic compounds, pigments (chlorophyll-/-b, lycopene, and β-carotene), monoterpenoids, and condensed tannins compared to HAE, while HAE, contains higher levels of soluble protein and sugars. Furthermore, HEE demonstrated remarkable antioxidant activity evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH●), 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS●+) and ferric reducing/antioxidant power (FRAP) assays. We have obtained comprehensive results highlighting the potential of HEE as a source of bioactive compounds with anticancer properties. Future studies should aim at identifying the chemical constituents responsible for the bioactivities observed, and focus on investigating HEE's effects, in in vivo preclinical cancer models.

Galectin-1 knockdown inhibits proliferation, migration, invasion and promotes apoptosis of lung adenocarcinoma cells in vitro

To investigate the effect of galectin-1 on biological behaviors of lung adenocarcinoma cells and the underlying mechanism. The expression levels of galectin-1 mRNA were detected in 8 pairs of lung adenocarcinoma tissues and adjacent normal tissues and in lung adenocarcinoma cell lines A549 and H1299 and normal bronchial epithelial cell line BEAS-2b using qRT-PCR. The effect of galectin-1 knockdown by RNA interference on the proliferation, invasion and migration abilities and apoptosis of lung adenocarcinoma cells were examined using CCK8 assay, Transwell assay, scratch assay and flow cytometry. Western blotting was performed to detect the expressions of apoptosis-related proteins BAX, BCL-2, and caspase-3 and the proteins involved in the AKT and ERK pathways. The mRNA expression of galectin-1 was significantly increased in lung cancer tissues and lung adenocarcinoma cell lines (P < 0.05). In lung adenocarcinoma cells, galectin-1 knockdown significantly inhibited cell proliferation, migration and invasion and obviously increased cell apoptosis rate (P < 0.05), causing also significant reduction of the phosphorylation level of ERK signaling pathway (P < 0.05). Galectin-1 knockdown inhibits proliferation, migration, and invasion and promotes apoptosis of lung adenocarcinoma cells, and this effect is mediated probably by inhibition of the phosphorylation levels of the ERK pathway.

HEY1-mediated cisplatin resistance in lung adenocarcinoma via epithelial-mesenchymal transition.

Lung cancer is one of the most common malignancies and the leading cause of cancer-related death in the world. In patients with advanced lung adenocarcinoma who are negative for driver gene mutations, platinum-based chemotherapy represented by cisplatin remain the standard of care. Therefore, studying the mechanism behind inevitable cisplatin resistance in lung adenocarcinoma is still important. In this study, the potentially related differential expression gene for cisplatin resistance in lung adenocarcinoma was screened in the GEO database. The expression level of HEY1 in cell lines of lung adenocarcinoma was detected and HEY1 expression was up-regulated in cisplatin-resistant lung adenocarcinoma tissues and cell lines A549/DDP. Patients with high HEY1 expression have poor prognosis after cisplatin therapy. Gain and loss function assays uncovered that HEY1 could regulate the cisplatin sensitivity of NSCLC cells. In vivo experiments have confirmed that silence of HEY1 expression can induce cisplatin resistance, and epithelial-mesenchymal transition (EMT) changes occur during this process. Mechanically, HEY1 silencing significantly up-regulated E-cadherin expression and down-regulated Vimentin in A549/DDP cells. While up-regulation of HEY1 resulted in down-regulation of E-cadherin and up-regulation of Vimentin in A549 cells. Immunohistochemical experiments confirmed that E-cadherin was significantly decreased, and Vimentin expression was significantly up-regulated in cisplatin-resistant lung adenocarcinoma tissues. HEY1 can mediate the occurrence of cisplatin-acquired resistance in lung adenocarcinoma, and the possible mechanism is to regulate the EMT. The results of this study can provide a new direction and target for clinical research on the reversal of cisplatin resistance in lung adenocarcinoma.

High expression levels of FANCI correlate with worse prognosis and promote tumor growth of lung adenocarcinoma partly via suppression of M1 macrophages

FANCI, a member of the Fanconi anemia (FA) complementation group, normally associates with FANCD2 to play an important role in ribosome biogenesis and DNA repair. However, the correlation of FANCI with prognostic value and the molecular mechanism in patients with lung adenocarcinoma (LUAD) remains unclear. In the present study, bioinformatics analysis was performed on LUAD data from TCGA and GEO databases, and further confirmed by in vitro experiments. We found that a high level of FANCI was significantly correlated with a worse survival probability in patients with LUAD. Moreover, the results from in vitro experiments revealed high levels of FANCI in LUAD specimens and cell lines. Knockdown of FANCI expression in A549 and H460 cells significantly inhibited cell viability and clone formation of LUAD cells in vitro and in vivo. Furthermore, high FANCI levels were negatively correlated with a variety of tumor-infiltrating immune cells. Importantly, the overexpression of FANCI significantly inhibited the activation of M1 macrophages. All the data demonstrated that FANCI was a useful prognostic biomarker in patients with LUAD, and knockdown of FANCI inhibited tumor growth of LUAD cells in vitro and in vivo, partly by suppressing the activation of M1 macrophages.

PRRX2 predicts poor survival prognosis, and promotes malignant phenotype of lung adenocarcinoma via transcriptional activates PSMD1

Introduction: Paired-related homeobox transcription factor 2 (PRRX2) has been proved involves in the pathogenesis of tumors, but the role of PRRX2 in lung adenocarcinoma (LUAD) is basically not clear. Materials and Methods: LUAD datasets were obtained from Gene Expression Omnibus datasets. Functional enrichment analyses were performed based on R language. Several online analysis tools were used for PRRX2 expression, survival curves, and immune cell infiltration analyses. CCK-8, flow cytometry assays were used to detect the cell proliferation and apoptosis. Dual luciferase reporter system and chromatin immunoprecipitation were used to explore the interaction of PRRX2 and Proteasome 26S subunit, non-ATPases 1 (PSMD1). Xenograft in nude mice was used to assess the function of PRRX2 regulation in vivo. Results and Discussion: Bioinformatics analyses found that PRRX2 was highly expressed in LUAD tissues and the high PRRX2 expression had a poor prognostic value. PRRX2 was highly expressed in LUAD clinical samples and cell lines. PRRX2 acted as a positive regulator of cell proliferation and a negative regulator of apoptosis. PRRX2 could bind with the PSMD1 promoter and regulate PSMD1 expression, thereby affected LUAD cells' malignant phenotype. Result of xenografts in nude mice confirmed that PRRX2 promotes LUAD tumor growth in vivo. Summary, our study results reveal the crucial roles for PRRX2 in the proliferation and apoptosis of LUAD progression and suggest that PRRX2 may regulate PSMD1 expression by combining with the PSMD1 promoter, thereby participating in the malignant behavior of LUAD.

Glycoprotein M6A Suppresses Lung Adenocarcinoma Progression via Inhibition of the PI3K/AKT Pathway.

Lung adenocarcinoma is the most common subtype of lung cancer and has high morbidity and mortality. Glycoprotein M6A (GPM6A) is a neuronal membrane glycoprotein reported to be related with cancer. However, studies on GPM6A in lung adenocarcinoma are rare. This study aimed to investigate the role of GPM6A in lung adenocarcinoma and its potential mechanism. GPM6A mRNA expression was analysed in 33 types of cancers using The Cancer Genome Atlas (TCGA) datasets. It was compared among normal lung tissues, lung adenocarcinoma tissues, and adjacent tissues using the Oncomine database. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to detect GPM6A expression in human lung adenocarcinoma cell lines (A549 and H1299) and normal pulmonary epithelial cells (BEAS-2B). When GPM6A was inhibited, cell proliferative capacity was detected by Cell Counting Kit 8 (CCK8), EdU, and colony formation assays. Cell migration ability was detected by wound healing and transwell assays. The expression of epithelial-mesenchymal transition (EMT) markers was detected by Western blotting (WB) and RT-qPCR. When GPM6A was overexpressed, cell proliferation and migration were detected again. Ten nude mice were subcutaneously injected with cells overexpressing GPM6A or empty vector, and the tumor size was recorded on day 14 and then measured every 3 days thereafter. The final tumor weight was measured on day 36. Furthermore, the expressions of phosphoinositide 3-kinase (PI3K), phosphorylated PI3K, AKT, and phosphorylated AKT were detected by WB. Results showed that GPM6A mRNA expression decreased in 15 types of tumors in TCGA dataset. GPM6A expression was lower in lung adenocarcinoma than in normal lung tissues or adjacent tissues in the Oncomine dataset. Similar results were found in lung adenocarcinoma cells. The function study showed that GPM6A downregulation enhanced the proliferation, migration, and EMT of lung adenocarcinoma cells, while GPM6A upregulation inhibited their development. The xenograft results suggested that GPM6A upregulation delayed tumor growth and reduced tumor weight. Moreover, WB showed that GPM6A knockdown activated the PI3K/AKT pathway, while GPM6A upregulation inhibited the activation of the PI3K/AKT pathway. In conclusion, GPM6A suppresses lung adenocarcinoma progression via inhibition of the PI3K/AKT pathway. Thus, GPM6A could be a possible treatment target for lung cancer therapy.

Capsaicin inhibits proliferation and induces apoptosis in human lung adenocarcinoma A549 cell line

Capsaicin is the main component of many hot peppers, exerts anticancer effects on various cancer cells by inducing apoptotic pathways. In addition, the ineffectiveness of this apoptotic effect of capsaicin on healthy cells provides a wide-ranging use of capsaicin. In recent years, many studies have been carried out to determine the safety of capsaicin use in lung cancer, which is a common cancer type worldwide with high mortality rates. In the present study anticancer effects of capsaicin were studied on A549 human lung adenocarcinoma cell line. Also, citotoxicity of this compound was studied on L929 mouse embryonic fibroblast cell line. Various concentration of capsaicin (3.90625-500 μM) effectively decreased cell viability in A549 cell line in a dose-dependent manner. Also, this antiproliferative effect of capsaicin was selective compared to L929 cell line. On the other hand, apoptosis inducing effects of capsaicin were studied by Annexin V-FITC and Caspase 3 assays by using IC50 and IC50/2 concentrations on A549 cell by flow cytometric methods. Our results revealed that the anticancer effects induced by capsaicin on A549 cell line involved apoptosis by inducing Caspase 3 pathway.

A multivalent activatable aptamer probe with ultralow background signal and high sensitivity for diagnosis of lung adenocarcinoma

Lung adenocarcinoma is the most common subtype of lung cancer. Developing a simple, rapid, and sensitive method for the detection of lung adenocarcinoma is helpful to reduce the clinical workload and facilitate clinical treatment. To detect lung adenocarcinoma cells, this study designed a multivalent activatable aptamer probe (multi-AP) using S1 aptamer that can specifically recognize A549 cells (a lung adenocarcinoma cell line). Firstly, the monovalent activatable aptamer probe (mono-AP) was designed by strand-displacement strategy and fluorescent resonance energy transfer (FRET). The multi-AP was constructed by mono-AP assembled on the nucleic acid scaffold obtained by hybridization chain reaction (HCR). The presence of the target cell activated the multi-AP, the complementary strand was released, and the fluorescence detection signal was reported based on the FRET. The multi-AP has good specificity and sensitivity for detecting A549 in different matrices and greatly reduces the background signal with the lowest detection limit of 6 cells/200 μL. Furthermore, the multi-AP could directly detect the lung adenocarcinoma cells in cytology specimens, indicating a good potential of the multi-AP in clinical cytology specimens for rapid diagnosis, such as rapid on-site cytological evaluation. Besides, the multi-AP was further modified with biotin (bio-multi-AP) and used to detect clinical cytology cell blocks, implying the value of bio-multi-AP in immunocytochemistry for accurate diagnosis of lung adenocarcinoma.

Comparison of EMT-Related and Multi-Drug Resistant Gene Expression, Extracellular Matrix Production, and Drug Sensitivity in NSCLC Spheroids Generated by Scaffold-Free and Scaffold-Based Methods.

Multicellular 3D tumor models are becoming a powerful tool for testing of novel drug products and personalized anticancer therapy. Tumor spheroids, a commonly used 3D multicellular tumor model, more closely reproduce the tumor microenvironment than conventional 2D cell cultures. It should be noted that spheroids can be produced using different techniques, which can be subdivided into scaffold-free (SF) and scaffold-based (SB) methods. However, it remains unclear, to what extent spheroid properties depend on the method of their generation. In this study, we aimed to carry out a head-to-head comparison of drug sensitivity and molecular expression profile in SF and SB spheroids along with a monolayer (2D) cell culture. Here, we produced non-small cell lung cancer (NSCLC) spheroids based on human lung adenocarcinoma cell line A549. Drug sensitivity analysis of the tested cell cultures to five different chemotherapeutics resulted in IC50 (A549-SB) > IC50 (A549-SF) > IC50 (A549-2D) trend. It was found that SF and SB A549 spheroids displayed elevated expression levels of epithelial-to-mesenchymal transition (EMT) markers and proteins associated with drug resistance compared with the monolayer A549 cell culture. Enhanced drug resistance of A549-SB spheroids can be a result of larger diameters and elevated deposition of extracellular matrix (ECM) that impairs drug penetration into spheroids. Thus, the choice of the spheroid production method can influence the properties of the generated 3D cell culture and their drug resistance. This fact should be considered for correct interpretation of drug testing results.

A Novel Preservation Method of Improving DNA Stability for Liquid-Based Cytology Specimens Using a Lung Adenocarcinoma Cell Line

A Novel Preservation Method of Improving DNA Stability for Liquid-Based Cytology Specimens Using a Lung Adenocarcinoma Cell Line