Immune Infiltration In Lung Adenocarcinoma Research Articles

Retraction Note: Lactate dehydrogenase D serves as a novel biomarker for prognosis and immune infiltration in lung adenocarcinoma

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1186/s12885-023-11221-6.

SASS6 promotes tumor proliferation and is associated with TP53 and immune infiltration in lung adenocarcinoma

The most common type of non-small cell lung cancer is lung adenocarcinoma (LUAD), which is characterized by high morbidity and poor survival. Up-regulation of SASS6 expression can lead to the progression of various malignant tumors. However, there are no relevant studies on the role of SASS6 in LUAD. SASS6 was highly expressed in most tumors, reflecting a good diagnostic value, and its overexpression in LUAD indicated discouraging overall prognosis. Functional enrichment analysis suggested that SASS6 was associated with cell cycle in LUAD. In addition, patients with high SASS6 expression had worse immune infiltration, but higher TMB and immune checkpoint, and higher sensitivity to multiple targeted drugs such as osimertinib. Cell experiments confirmed that knockdown of SASS6 could inhibit the viability of tumor cells.SASS6 has important value in the diagnosis of cancer. In particular, SASS6 is a crucial factor in the progression of LUAD, and has important clinical value, especially in the diagnosis, prognosis and treatment

Construction of a disulfidptosis-associated lncRNAs risk model to predict prognosis and immuno-infiltration analysis of lung adenocarcinoma

Objective: To develop a risk model based on LncRNAs associated with disulfidptosis to forecast the prognosis and assess immune infiltration of Lung adenocarcinoma (LUAD). Methods: This study employed a bioinformatics approach. The study was conducted from March 29, 2023 and concluded on July 1, 2023 at Guangzhou University of Chinese Medicine, Guangzhou, China. Transcriptomic data specific to LUAD were collected from TCGA database. Disulfidptosis-related LncRNAs were preliminarily screened using co-expression analysis, followed by screening using Lasso regression and Cox regression to identify LncRNAs. Subsequently, prognostic prediction models were constructed. To assess the model, survival analysis, subject operating characteristic curves, and calibration curves were employed. To evaluate the tumor microenvironment, the “estimate” package was used, while the “ggpubr” package was utilized to visualize the variations. Additionally, we employed CIBERSORT to examine immune cell infiltration abundance. Results: A prognostic prediction model was constructed using five LncRNAs. The high-risk group displayed a shorter overall survival and progression-free survival (P<0.05). The concordance index was calculated as 0.704 (95% CI: 0.654-0.754). GSEA analysis reveals that high risk group is associated with the cell cycle pathway and steroid hormone biosynthesis pathway, while the low-risk group is associated with hematopoietic cell pathway and allograft rejection pathway. Immune cell infiltration analysis indicated associations between the prognostic model and activated T cells CD4 memory, T cells CD8, etc. Conclusions: The risk model of Disulfidptosis-related LncRNAs can predict the prognosis of LUAD and evaluate the immune infiltration, providing a new direction for the treatment of LUAD. doi: https://doi.org/10.12669/pjms.40.10.9025 How to cite this: Liu J, Nie H, Du W, Song W. Construction of a disulfidptosis-associated lncRNAs risk model to predict prognosis and immuno-infiltration analysis of lung adenocarcinoma. Pak J Med Sci. 2024;40(10):2368-2372. doi: https://doi.org/10.12669/pjms.40.10.9025 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

MEF2C is a Potential Prognostic Biomarker and is Correlated with Immune Infiltrates in Lung Adenocarcinoma.

The role of Myocyte Enhancer Factor 2 C (MEF2C) in lung adenocarcinoma (LUAD) is unclear. To address this gap in knowledge, we employed bioinformatics analysis and experimental validation in this study. This study investigated MEF2C expression across a spectrum of cancers, with a specific focus on lung adenocarcinoma (LUAD), utilizing Cancer Genome Atlas (TCGA) data to assess its potential as a diagnostic marker. The study also investigated correlations between MEF2C expression and clinical traits and prognostic indicators of LUAD. Additionally, this study also delved into the regulatory mechanisms of MEF2C, examining its connections to immune system interactions, immune checkpoint genes, tumor mutational burden (TMB), and the sensitivity of LUAD to various drugs. Through single-cell sequencing of LUAD cells and genetic variation of MEF2C in LUAD, we explored the expression of MEF2C in cell lines and verified it by quantitative real-time PCR (qRT-PCR). MEF2C exhibited aberrant expression in both pan-cancer and LUAD. In individuals with LUAD, diminished levels of MEF2C expression were notably linked to the effectiveness of primary therapy outcome (p = 0.025), gender (p < 0.001), and the subdivision of anatomic neoplasms 2 (p = 0.011). A decline in MEF2C levels was also found to be significantly related to reduced overall survival (OS) in LUAD patients (p = 0.026). The presence of MEF2C was recognized as a standalone factor predictive of prognosis in LUAD (p = 0.029). MEF2C was found to be involved in multiple biological pathways, such as those involving cell adhesion molecules. Additionally, its expression was correlated with the extent of immune cell presence, the activity of immune checkpoint genes, and TMB in LUAD. Notably, an inverse relationship was observed between MEF2C expression and the sensitivity to several agents, including Topotecan, Irinotecan, Panobinostat, Nilotinib, and Tp38-279, within the context of LUAD. Furthermore, MEF2C was found to be significantly negatively regulated in LUAD cell lines. The results imply that MEF2C could be a valuable indicator for predicting outcomes and a possible target for immunotherapy for LUAD patients.

Disulfidptosis-related gene SLC7A11 predicts prognosis and indicates tumor immune infiltration in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is closely associated with factors such as smoking and metabolic disorders. A unique form of cell death known as disulfidptosis, which is regulated by genes like SLC7A11, has emerged as an area of interest; however, its effect on the immune microenvironment in the context of cancer remains largely unexplored. The aim of this study was to analyze the immunoregulatory role of disulfidptosis-related genes in LUAD to unveil and underscore their significance in the process of immune regulation. This study examined the role of disulfidptosis-related genes in LUAD using data from The Cancer Genome Atlas (TCGA) with a particular focus on immune infiltration and the function of SLC7A11. The research employed a clustering analysis, survival analysis, and immune function assessment, integrating both bulk and single-cell RNA sequencing data, to gain a comprehensive understanding of disulfidptosis in LUAD. The analysis revealed three distinct LUAD clusters, each characterized by different survival rates and patterns of immune cell infiltration. Notably, high expression levels of SLC7A11 were associated with a poor prognosis and mechanisms of immune evasion. High SLC7A11 expression is correlated with a poor prognosis and immune evasion in LUAD. These results underscore the significant role of SLC7A11 in the progression of disulfidptosis and LUAD. This study sheds new light on the role of disulfidptosis in LUAD, particularly highlighting the immunoregulatory effects of SLC7A11. The findings suggest that targeting SLC7A11 could lead to the development of novel therapeutic strategies aimed at enhancing the response to immunotherapy in LUAD patients. To substantiate these results, further experimental validation is needed.

RPL22L1 is a novel biomarker for prognosis and immune infiltration in lung adenocarcinoma, promoting the growth and metastasis of LUAD cells by inhibiting the MDM2/P53 signaling pathway.

The ribosomal protein L22-like1 (RPL22L1) is a constituent of the 60 S ribosomal subunit whose function in lung adenocarcinoma (LUAD) remains ambiguous. This study aims to elucidate the role of RPL22L1 in LUAD through a thorough analysis and experimental validation. Our findings indicate that RPL22L1 exhibits abnormal expression patterns in various cancer types, including LUAD. Moreover, a statistically significant association was observed between elevated levels of RPL22L1 expression in LUAD patients and several clinical parameters, such as pathological stage (p = 0.0083) and gender (p = 0.0038). The high expression of RPL22L1 in LUAD demonstrated a significant association with poorer overall survival (OS) (p = 0.005), progression-free survival (PFS) (p = 0.027), and disease-specific survival (p = 0.015). The expression of RPL22L1 in LUAD (p = 0.005) was identified as an independent prognostic factor. Additionally, RPL22L1 expression in LUAD was found to be correlated with immune infiltration, immune checkpoint genes, TMB/MSI, and mRNAsi. Notably, the expression of RPL22L1 exhibited significant negative correlations with 1-BET-762, Trametinib, and WZ3105 in LUAD. The RPL22L1 gene exhibited up-regulation in multiple individual cells of LUAD, leading to a comparatively shorter PFS in the RPL22L1 variant group as opposed to the RPL22L1 variant-free group in LUAD. Significantly increased expression of RPL22L1 was noted in LUAD cell lines, where it was found to enhance the growth and metastasis of LUAD cells by suppressing the MDM2/P53 signaling pathway. Therefore, RPL22L1 may serve as a promising prognostic biomarker and therapeutic target for patients with LUAD.

Comprehensive Analysis and Experimental Validation of TLL2 as a Potential New Prognostic Biomarker Associated with Immune Infiltration in Lung Adenocarcinoma.

The precise function of Tolloid Like 2 (TLL2) remains uncertain within the context of Lung Adenocarcinoma (LUAD). The primary objective of this investigation was to conduct a thorough analysis. To assess its diagnostic utility, data from The Cancer Genome Atlas (TCGA) database were used to assess TLL2 expression in pan-cancer and LUAD. The study has also investigated the correlation between TLL2 expression levels and LUAD symptoms and prognosis. Furthermore, the study has explored possible regulatory networks involving TLL2, including its association with immune infiltration, tumor stemness index (mRNAsi), and drug sensitivity in LUAD. We have explored TLL2 expression in single-cell sequencing of LUAD and the genomic variation and clinical significance of TLL2 in LUAD. The expression of TLL2 has been validated in GSE87340 and cell lines by quantitative Real-time PCR (qRT-PCR). An abnormal expression of TLL2 has been found in pan-cancer and LUAD. In LUAD patients, elevated levels of TLL2 were significantly related to the T stage (p = 0.046) and the pathological stage (p = 0.016). The expression of TLL2 in patients with LUAD was significantly associated with poorer Overall Survival (OS) (p < 0.001). The expression of TLL2 was determined to be an independent predictor of poorer OS (p = 0.042). TLL2 was associated with ribosome, neuroactive ligand-receptor interaction, allograft rejection, ECM receptor interaction, asthma, porphyrin and chlorophyll metabolism, focal adhesion, pentose and glucuronate inter-conversions, and ascorbate and aldarate metabolism. The expression of TLL2 in LUAD was correlated with immune infiltration and mRNAsi. The expression of TLL2 was significantly and negatively correlated with TAK-715, XMD13-2, STF-62247, OSI-930, and EHT-1864 in LUAD. The TLL2 gene was up- -regulated in multiple individual LUAD cells. LUAD patients with altered TLL2 had a shorter PFS as opposed to those with unaltered TLL2. The expression of TLL2 was significantly increased in LUAD cells. For patients with LUAD, TLL2 may serve as an immunotherapeutic target and a useful prognosis biomarker.

PLCG2, A Regulator of Lung Adenocarcinoma Proliferation and Migration Associated with Immune Infiltration.

Results from the TCGA database showed that phosphatidylinositol-specific phospholipase Cγ2 (PLCG2) expression level in Lung Adenocarcinoma (LUAD) was notably decreased compared to adjacent tissues, so we unveiled its role of LUAD. This study aims to explore the expression and clinical significance of Phosphatidyl-inositol-specific phospholipase Cγ2 (PLCG2) in lung adenocarcinoma (LUAD) cells and its role in cell proliferation and metastasis. Differential PLCG2 mRNA and protein levels between LUAD tissues and adjacent tissues were analyzed from the TCGA database, TIMER, and UALCAN database. Differentially expressed genes were screened for patients in the high and low PLCG2 mRNA expression groups by the R package as well as GSEA. The expression level of PLCG2 in LUAD cells was detected using qRT-PCR and CCK8, clone formation, Transwell, and Western blot assays. PLCG2 was lowly expressed in LUAD and did not significantly correlate with the prognosis of LUAD. PLCG2 expression levels varied significantly in terms of patients' gender, age, T, N, and pathological stage. GO/KEGG enrichment analysis showed that co-expression of PLCG2 was mainly associated with the immune response- regulating cell-surface receptors, and so on. GSEA analysis showed enrichment pathways of PLCG2-related differential gees were primarily associated with the olfactory transduction pathway, ribosome, etc. R software analysis revealed a significant correlation between PLCG2 expression and six types of immune-infiltrat-ing cells, positively correlated with immune checkpoint-related genes and negatively regulated by tumor mutational load. Overexpressing PLCG2 showed reduced LUAD cell proliferation, clone formation, cell migration and invasion, and epithelial-mesenchymal transition-associated proteins, compared with the control group. PLCG2 is lowly expressed in LUAD tissues and is involved in immune infiltration of LUAD, inhibiting LUAD cell proliferation and metastasis.

MiR-137 mediated high expression of TIGD1 promotes migration, invasion, and suppresses apoptosis of lung adenocarcinoma

ObjectivesTigger transposable element-derived 1 (TIGD1) expression and its underlying functions and regulatory mechanisms in lung adenocarcinoma (LUAD) remain unknown. Therefore, we intended to explore the expression, potential functions, and regulatory mechanisms of TIGD1 in LUAD. Materials and methodsTIGD1 expression in LUAD tissues was determined by immunohistochemistry analysis of a tissue microarray. Functional experiments were conducted to determine how TIGD1 affects LUAD tumorigenesis and metastasis. The molecular mechanisms by which TIGD1 induces LUAD progression were determined. ResultsTIGD1 was upregulated in LUAD tissues and was related to lymph node metastases. TIGD1 knockdown suppressed LUAD cell proliferation, migration, and invasion, while promoted cell apoptosis. Furthermore, decreased metastatic nodules were observed in the TIGD1 knockdown mouse metastasis model. Moreover, microarray analysis was performed to determine the potential downstream genes of TIGD1 in LUAD. Hallmark pathway analysis revealed that the downstream genes of TIGD1 were involved in epithelial-mesenchymal transition (EMT). Western blotting confirmed that vimentin and TWIST was downregulated in TIGD1 knockdown cells, while E-cadherin was upregulated. Ingenuity pathway and hallmark pathway analyses revealed that TIGD1 regulated the interleukin-6 signaling pathway and related gene members. Western blotting, quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay indicated that downregulation of TIGD1 decreased interleukin-6 and CXCL1 expression. TIGD1 expression was negatively correlated with immune infiltration in LUAD. The upstream microRNA of TIGD1 was predicted, and subsequent luciferase reporter gene experiments confirmed the interactions between miR-137 and TIGD1. The expression of miR-137 was significantly downregulated in LUAD tissues and miR-137 suppressed the proliferation, migration, and invasion of LUAD cells, partially through negatively regulating the expression of TIGD1. ConclusionOur findings suggest that TIGD1, which was regulated by miR-137, contributed to LUAD progression by promoting cell proliferation, migration, invasion, and EMT and suppressing cell apoptosis.

Circ_BBS9 as an early diagnostic biomarker for lung adenocarcinoma: direct interaction with IFIT3 in the modulation of tumor immune microenvironment.

Introduction: Circular RNAs (circRNAs) have been identified as significant contributors to the development and advancement of cancer. The objective of this study was to examine the expression and clinical implications of circRNA circ_BBS9 in lung adenocarcinoma (LUAD), as well as its potential modes of action. The expression of Circ_BBS9 was examined in tissues and cell lines of LUAD through the utilization of microarray profiling, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis. In this study, we assessed the impact of circ_BBS9 on the proliferation of LUAD cells, as well as its influence on ferroptosis and tumor formation. To analyze these effects, we employed CCK-8 assays and ferroptosis assays. The identification of proteins that interact with Circ_BBS9 was achieved through the utilization of RNA pull-down and mass spectrometry techniques. A putative regulatory network comprising circ_BBS9, miR-7150, and IFIT3 was established using bioinformatics study. The investigation also encompassed the examination of the correlation between the expression of IFIT3 and the invasion of immune cells. Circ_BBS9 was significantly downregulated in LUAD tissues and cell lines. Low circ_BBS9 expression correlated with poor prognosis. Functional experiments showed that circ_BBS9 overexpression inhibited LUAD cell proliferation and promoted ferroptosis in vitro and suppressed tumor growth in vivo. Mechanistically, circ_BBS9 was found to directly interact with IFIT3 and regulate its expression by acting as a sponge for miR-7150. Additionally, IFIT3 expression correlated positively with immune infiltration in LUAD. Circ_BBS9 has been identified as a tumor suppressor in lung adenocarcinoma (LUAD) and holds promise as a diagnostic biomarker. The potential mechanism of action involves the modulation of ferroptosis and the immunological microenvironment through direct interaction with IFIT3 and competitive binding to miR-7150. The aforementioned findings offer new perspectives on the pathophysiology of LUAD and highlight circ_BBS9 as a potentially valuable target for therapeutic interventions.

HES6 Mediates Oxidative Phosphorylation Pathway to Promote Immune Infiltration of CD8 + T Cells in Lung Adenocarcinoma.

Tumor immunotherapy has recently gained popularity as a cancer treatment strategy. The molecular mechanism controlling immune infiltration in lung adenocarcinoma (LUAD) cells, however, is not well characterized. Investigating the immune infiltration modulation mechanism in LUAD is crucial. LUAD patient samples were collected, and HES6 expression and immune infiltration level of CD8 + T cells in patient tissues were analyzed. Bioinformatics was utilized to identify binding relationship between E2F1 and HES6, and enrichment pathway of HES6. The binding of E2F1 to HES6 was verified using dual-luciferase and ChIP experiments. HES6 and E2F1 expression in LUAD cells was detected. LUAD cells were co-cultured with CD8 + T cells, and the CD8 + T cell killing level, IFN-γ secretion, and CD8 + T-cell chemotaxis level were measured. Expression of key genes involved in oxidative phosphorylation was detected, and the oxygen consumption rate of LUAD cells was assessed. A mouse model was constructed to assay Ki67 expression and apoptosis in tumor tissue. High expression of HES6 promoted CD8 + T-cell infiltration and enhanced T-cell killing ability through oxidative phosphorylation. Further bioinformatics analysis, molecular experiments, and cell experiments verified that E2F1 negatively regulated HES6 by oxidative phosphorylation, which suppressed CD8 + T-cell immune infiltration. In addition, in vivo assays illustrated that silencing HES6 repressed tumor cell immune evasion. E2F1 inhibited HES6 transcription, thereby mediating oxidative phosphorylation to suppress immune infiltration of CD8 + T cells in LUAD. The biological functions and signaling pathways of these genes were analyzed, which may help to understand the possible mechanisms regulating immune infiltration in LUAD.

Effect of ZIC2 on immune infiltration and ceRNA axis regulation in lung adenocarcinoma via bioinformatics and experimental studies

ObjectiveThis study aimed to conclude the effect and mechanism of ZIC2 on immune infiltration in lung adenocarcinoma (LUAD). MethodsExpression of ZIC2 in several kinds of normal tissues of TCGA data was analyzed and its correlation with the baseline characteristic of LUAD patients were analyzed. The immune infiltration analysis of LUAD patients was performed by CIBERSORT algorithm. The correlation analysis between ZIC2 and immune cell composition was performed. Additionally, the potential upstream regulatory mechanisms of ZIC2 were predicted to identify the possible miRNAs and lncRNAs that regulated ZIC2 in LUAD. In vitro and in vivo experiments were also conducted to confirm the potential effect of ZIC2 on cell proliferation and invasion ability of LUAD cells. ResultsZIC2 expression was decreased in various normal tissues, but increased in multiple tumors, including LUAD, and correlated with the prognosis of LUAD patients. Enrichment by GO and KEGG suggested the possible association of ZIC2 with cell cycle and p53 signal pathway. ZIC2 expression was significantly correlated with T cells CD4 memory resting, Macrophages M1, and plasma cells, indicating that dysregulated ZIC2 expression in LUAD may directly influence immune infiltration. ZIC2 might be regulated by several different lncRNA-mediated ceRNA mechanisms. In vitro experiments validated the promotive effect of ZIC2 on cell viability and invasion ability of LUAD cells. In vivo experiments validated ZIC2 can accelerate tumor growth in nude mouse. ConclusionZIC2 regulated by different lncRNA-mediated ceRNA mechanisms may play a critical regulatory role in LUAD through mediating the composition of immune cells in tumor microenvironment.

Downregulation of DIP2B as a prognostic marker inhibited cancer proliferation and migration and was associated with immune infiltration in lung adenocarcinoma via CCND1 and MMP2

BackgroundDIP2B is related to cancer progression. This study investigated the roles and pathways of DIP2B in lung adenocarcinoma (LUAD). MethodsDIP2B expression and the relationship between survival time of cancer patients and DIP2B expression were analyzed. The relationship between DIP2B expression and survival time in LUAD patients was evaluated by a meta-analysis. Cox and survival analyses were used to evaluate the prognostic factors and construct a prognostic nomogram. The mechanisms and effects of DIP2B and the relationship between DIP2B expression and the immune microenvironment were investigated using bioinformatics, CCK-8, western blotting, and transwell experiments. ResultsDIP2B was overexpressed in LUAD tissues. DIP2B overexpression was associated with shorter prognosis and was an unfavorable risk factor for prognosis in LUAD patients. DIP2B co-expressed genes were involved in cell division, DNA repair, cell cycle, and others. Inhibition of DIP2B expression could downregulate the proliferation, migration, and invasion of LUAD A549 and H1299 cells, which was related to the decrease in CCND1 and MMP2 protein expression. BRCA1 overexpression was associated with short prognosis, and the nomogram formed by DIP2B and BRCA1 was associated with a poor prognosis in LUAD patients. DIP2B expression correlated with immune cells (such as CD8 T cells, Tcm, and iDCs) and cell markers. ConclusionDIP2B is a potential biomarker of poor prognosis and the immune microenvironment in LUAD. Inhibition of DIP2B expression downregulated cancer cell proliferation, migration, and invasion, which might be related to the decrease in CCND1 and MMP2 protein expression. DIP2B-related nomograms might be useful tools for predicting the prognosis of LUAD patients.

DEPDC1B is a Novel Direct Target of B-Myb and Contributes to Malignant Progression and Immune Infiltration in Lung Adenocarcinoma.

Lung cancer is the primary cause of cancer-related deaths, with one of the highest incidence and mortality rates of all malignant tumors. Dysregulated expression of DEPDC1B has been reported to occur in various tumor types. However, the functional implications of this alteration in lung adenocarcinoma (LUAD) and the underlying molecular mechanism remains unclear. In this study, we investigated the role and clinical significance of DEPDC1B in LUAD. The expression of DEPDC1B in LUAD and its relationship with prognosis were systematically evaluated in several publically available datasets. The effects of DEPDC1B knockdown on the proliferation and motility of LUAD cells were assessed using the JULI Stage Real-time Cell History Recorder, while the effect of knockdown on the cell cycle was studied by flow cytometry. Furthermore, RNA-Sequencing (RNA-Seq) analysis was conducted to identify the downstream target genes and pathways regulated by DEPDC1B. Correlations between the expression of DEPDC1B and immune cell infiltration, immunotherapy resistance, and chemoresistance were also examined. Additionally, molecular biological methods were used to explore the regulatory mechanism of B-Myb on DEPDC1B expression. DEPDC1B was found to be upregulated in LUAD patients and this was associated with poor clinical outcomes. Knockdown of DEPDC1B inhibited cell growth, migration and motility, as well as cell cycle progression. Knockdown also resulted in the down-regulation of several downstream genes, including NID1, FN1, and EGFR, as well as the inactivation of multiple critical pathways, such as the ERK and PI3K-AKT pathways. Analysis of the tumor immuno-environment in LUAD revealed that high DEPDC1B expression was associated with an abundance of activated CD4+ memory T cells, M0 macrophages, M1 macrophages, and CD8+ T cells. Moreover, these tumors responded poorly to immunotherapy. Analysis of chemo-drug sensitivity showed that LUADs with high DEPDC1B expression were more responsive to frontline chemotherapeutic drugs such as Vinorelbine, Cisplatin, and Etoposide. Additionally, mechanistic investigations revealed that DEPDC1B is a direct target gene of B-Myb, and that its knockdown attenuated the proliferation and motility effects of B-Myb. In summary, our findings indicate that DEPDC1B is a critical regulator during the malignant progression of LUAD. DEPDC1B could therefore be a promising prognostic marker and therapeutic target in LUAD diagnosis and treatment.

Identification of immune-associated biomarker for predicting lung adenocarcinoma: bioinformatics analysis and experiment verification of PTK6

BackgroundAbnormal expression of protein tyrosine kinase 6 (PTK6) has been proven to be involved in the development of gynecological tumors. However, its immune-related carcinogenic mechanism in other tumors remains unclear.ObjectiveThe aim of this study was to identify PTK6 as a novel prognostic biomarker in pan-cancer, especially in lung adenocarcinoma (LUAD), which is correlated with immune infiltration, and to clarify its clinicopathological and prognostic significance.MethodsThe prognostic value and immune relevance of PTK6 were investigated by using bio-informatics in this study. PTK6 expression was validated in vitro experiments (lung cancer cell lines PC9, NCI-H1975, and HCC827; human normal lung epithelial cells BEAS-2B). Western blot (WB) revealed the PTK6 protein expression in lung cancer cell lines. PTK6 expression was inhibited by Tilfrinib. Colony formation and the Cell Counting Kit-8 (CCK-8) assay were used to detect cell proliferation. The wound healing and trans-well were performed to analyze the cell migration capacity. Then flow cytometry was conducted to evaluate the cell apoptosis. Eventually, the relationship between PTK6 and immune checkpoints was examined. WB was used to estimate the PD-L1 expression at different Tilfrinib doses.ResultsPTK6 was an independent predictive factor for LUAD and was substantially expressed in LUAD. Pathological stage was significantly correlated with increased PTK6 expression. In accordance with survival analysis, poor survival rate in LUAD was associated with a high expression level of PTK6. Functional enrichment of the cell cycle and TGF-β signaling pathway was demonstrated by KEGG and GSEA analysis. Moreover, PTK6 expression considerably associated with immune infiltration in LUAD, as determined by immune analysis. Thus, the result of vitro experiments indicated that cell proliferation and migration were inhibited by the elimination of PTK6. Additionally, PTK6 suppression induced cell apoptosis. Obviously, PD-L1 protein expression level up-regulated while PTK6 was suppressed.ConclusionPTK6 has predictive value for LUAD prognosis, and could up regulated PD-L1.

Role of Radiation-related Lung Function Genes in Prognosis and Immune Infiltration of Lung Adenocarcinoma.

Lung adenocarcinoma (LUAD) is a common malignant tumor with no obvious clinical symptoms in its early stages. Patients can be divided into radiotherapysensitive groups (RS) and radiotherapy-resistant groups (RR) due to their varying conditions. The therapeutic effect of radiotherapy is quite different between the two groups. Therefore, this paper explores the role of radiation-related lung function genes in LUAD and its immune landscape. Firstly, we divided LUAD samples from the TCGA cohort into RS and RR groups and analyzed differential expression to obtain differentially expressed genes (DEGs). Then, DEGs and patients' grouping information were input into the weighted co-expression network, and the genes in the radiotherapy-related modules were identified. Furthermore, after the intersection of DEGs and lung function-related genes, the prognosis-related genes were obtained through univariate Cox and Lasso-Cox analyses, respectively, and the risk model was constructed. Finally, the differences in prognosis and immunity of the samples in the risk model were explored. Additionally, we also performed a qPCR experiment on lung function-related genes. In this paper, radiation-related genes of LUAD were identified through a series of bioinformatics analyses. By conducting enrichment analysis on these genes, several pathways related to LUAD radiation were identified, and DEGs associated with significant prognosis were determined. Furthermore, a radiation-related risk model of LUAD was developed. All samples were divided into high-risk and low-risk groups based on the risk score, and the differences in immune cell infiltration abundance and immune function between these groups were evaluated. The qPCR experimental results demonstrated a significant difference in the expression of genes related to lung function. The prognosis-related genes identified in this paper and the risk model created can serve as a reference for diagnosing and treating LUAD.

Identification and Verification of Metabolism-related Immunotherapy Features and Prognosis in Lung Adenocarcinoma.

Lung cancer is a frequent malignancy with a poor prognosis. Extensive metabolic alterations are involved in carcinogenesis and could, therefore, serve as a reliable prognostic phenotype. Our study aimed to develop a prognosis signature and explore the relationship between metabolic characteristic-related signature and immune infiltration in lung adenocarcinoma (LUAD). TCGA-LUAD and GSE31210 datasets were used as a training set and a validation set, respectively. A total of 513 LUAD samples collected from The Cancer Genome Atlas database (TCGA-LUAD) were used as a training dataset. Molecular subtypes were classified by consensus clustering, and prognostic genes related to metabolism were analyzed based on Differentially Expressed Genes (DEGs), Protein-Protein Interaction (PPI) network, the univariate/multivariate- and Lasso- Cox regression analysis. Two molecular subtypes with significant survival differences were divided by the metabolism gene sets. The DEGs between the two subtypes were identified by integrated analysis and then used to develop an 8-gene signature (TTK, TOP2A, KIF15, DLGAP5, PLK1, PTTG1, ECT2, and ANLN) for predicting LUAD prognosis. Overexpression of the 8 genes was significantly correlated with worse prognostic outcomes. RiskScore was an independent factor that could divide LUAD patients into low- and high-risk groups. Specifically, high-risk patients had poorer prognoses and higher immune escape. The Receiver Operating Characteristic (ROC) curve showed strong performance of the RiskScore model in estimating 1-, 3- and 5-year survival in both training and validation sets. Finally, an optimized nomogram model was developed and contributed the most to the prognostic prediction in LUAD. The current model could help effectively identify high-risk patients and suggest the most effective drug and treatment candidates for patients with LUAD.

Potential association of HSPD1 with dysregulations in ribosome biogenesis and immune cell infiltration in lung adenocarcinoma: An integrated bioinformatic approach.

Lung adenocarcinoma (LUAD) is a major histological subtype of lung cancer with a high mortality rate worldwide. Heat shock protein family D member 1 (HSPD1, also known as HSP60) is reported to be increased in tumor tissues of lung cancer patients compared with healthy control tissues. We aimed to investigate the roles of HSPD1 in prognosis, carcinogenesis, and immune infiltration in LUAD using an integrative bioinformatic analysis. HSPD1 expression in LUAD was investigated in several transcriptome-based and protein databases. Survival analysis was performed using the KM plotter and OSluca databases, while prognostic significance was independently confirmed through univariate and multivariate analyses. Integrative gene interaction network and enrichment analyses of HSPD1-correlated genes were performed to investigate the roles of HSPD1 in LUAD carcinogenesis. TIMER and TISIDB were used to analyze correlation between HSPD1 expression and immune cell infiltration. The mRNA and protein expressions of HSPD1 were higher in LUAD compared with normal tissues. High HSPD1 expression was associated with male gender and LUAD with advanced stages. High HSPD1 expression was an independent prognostic factor associated with poor survival in LUAD patients. HSPD1-correlated genes with prognostic impact were mainly involved in aberrant ribosome biogenesis, while LUAD patients with high HSPD1 expression had low tumor infiltrations of activated and immature B cells and CD4+ T cells. HSPD1 may play a role in the regulation of ribosome biogenesis and B cell-mediated immunity in LUAD. It could serve as a predictive biomarker for prognosis and immunotherapy response in LUAD.

CCND2 is a prognostic biomarker and correlates with immune infiltration in lung adenocarcinoma.

CCND2 expression influences the growth and proliferation of cancer cells and plays a crucial role in immune response of tumor. However, few studies focused on the correlation between CCND2 and lung adenocarcinoma (LUAD) in terms of prognosis and tumor immune infiltration. Original LUAD case data were screened from The Cancer Genome Atlas (TCGA) database. Using R software, we analyzed differently expressed CCND2 between LUAD and adjacent normal tissues. Kaplan-Meier analysis was conducted to determine the relationship between CCND2 expression and the overall survival of LUAD patients, and Cox regression analysis was performed to identify the independently prognostic risk factors for LUAD. Using TIMER (Tumor Immune Estimation Resource) and CIBERSORTx (Cell-type Identification by Estimating Relative Subsets of known RNA Transcripts) databases, the connection between CCND2 expression and LUAD immune infiltration was investigated. The level of CCND2 was significantly lower in LUAD than in adjacent normal tissues [adjusted P<0.05 and log2 fold change (FC) =-1.33]. LUAD patients who expressed lower CCND2 had a shorter overall survival (P=0.046) and CCND2 was an independently prognostic risk factor for LUAD [hazard ratio (HR): 0.77, P=0.049]. In LUAD patients, CCND2 expression was positively associated with the levels of B cells (r=0.159, P=4.00e-04), CD8+ T cells (r=0.287, P=7.88e-11), CD4+ T cells (r=0.301, P=8.14e-12), macrophages (r=0.128, P=4.57e-03), neutrophils (r=0.373, P=1.07e-17), and myeloid dendritic cells (r=0.284, P=1.43e-10). The levels of B cells and macrophages had significantly association with the overall survival of LUAD patients. CIBERSORTx showed that the proportions of naive B cells, resting dendritic cells, and macrophages M1 were higher in the low CCND2 expression group (P<0.05); whereas macrophages M1, activated natural killer (NK) cells, and resting CD4+ memory cells were lower (P<0.05). CCND2 can be exploited as a novel prognostic biomarker involved in immune infiltration of LUAD, hence providing new preventative and therapeutic options for LUAD.

A novel disulfidptosis-related prognostic gene signature and experimental validation identify ACTN4 as a novel therapeutic target in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is a prevalent form of malignancy globally. Disulfidptosis is novel programmed cell death pathway based on disulfide proteins, may have a positive impact on the development of LUAD treatment strategies. To investigate the impact of disulfidptosis-related genes (DRGs) on the prognosis of LUAD, developed a risk model to facilitate the diagnosis and prognostication of patients. We also explored ACTN4 (DRGs) as a new therapeutic biomarker for LUAD. We investigated the expression patterns of DRGs in both LUAD and noncancerous tissues. To assess the prognostic value of the DRGs, we developed risk models through univariate Cox analysis and lasso regression. The expression and function of ACTN4 was evaluated by qRT-PCR, immunohistochemistry and in vitro experiments. The TIMER examined the association between ACTN4 expression and immune infiltration in LUAD. Ten differentially expressed DRGs were identified. And ACTN4 was identified as potential risk factors through univariate Cox regression analysis (P< 0.05). ACTN4 expression and riskscore were used to construct a risk model to predict overall survival in LUAD, and high-risk demonstrated a significantly higher mortality rate compared to the low-risk cohort. qRT-PCR and immunohistochemistry assays indicated ACTN4 was upregulated in LUAD, and the upregulation was associated with clinicopathologic features. In vitro experiments showed the knockdown of ACTN4 expression inhibited the proliferation in LUAD cells. The TIMER analysis demonstrated a correlation between the expression of ACTN4 and the infiltration of diverse immune cells. Elevated ACTN4 expression was associated with a reduction in memory B cell count. Additionally, the ACTN4 expression was associated with m6A modification genes. Our study introduced a prognostic model based on DRGs, which could forecast the prognosis of patients with LUAD. The biomarker ACTN4 exhibits promise for the diagnosis and management of LUAD, given its correlation with tumor immune infiltration and m6A modification.