Lung adenocarcinoma: from molecular basis to genome-guided therapy and immunotherapy

Predictive value of spectral computed tomography parameters for EGFR gene mutation in non-small-cell lung cancer

AIM

To explore the predictive value of morphological signs and quantitative parameters from spectral CT for EGFR gene mutations in intermediate and advanced non-small-cell lung cancer (NSCLC).

MATERIALS AND METHODS

This retrospective observational study included patients with intermediate or advanced NSCLC at Xinjiang Medical University Affiliated Tumor Hospital between January 2017 and December 2019. The patients were divided into the EGFR gene mutation-positive and -negative groups.

RESULTS

Seventy-nine patients aged 60.75 ± 9.66 years old were included: 32 were EGFR mutation-positive, and 47 were negative. There were significant differences in pathological stage (P<0.001), tumor diameter (P=0.019), lobulation sign, intrapulmonary metastasis, mediastinal lymph node metastasis, distant metastasis (P<0.001), bone metastasis (P<0.001), arterial phase normalized iodine concentration (NIC) (P=0.001), venous phase NIC (P=0.001), slope of the energy spectrum curve (λ) (P<0.001), and CT value at 70 keV in arterial phase (P=0.004) and venous phase (P=0.003) between the EGFR mutation-positive and -negative patients. The multivariable logistic regression analysis showed that intrapulmonary metastasis, distant metastasis, venous phase NIC, venous phase λ, and pathological stage were independent factors predicting EGFR gene mutations, with high diagnostic power (AUC = 0.975, 91.5% sensitivity, and 90.6% specificity).

CONCLUSION

The pathological stage and the spectral CT parameters of intrapulmonary metastasis, distant metastasis, venous phase NIC, and venous phase λ might pre-operatively predict EGFR gene mutations in intermediate and advanced NSCLC.

Comprehensive analysis of lung adenocarcinoma: Unveiling differential gene expression, survival-linked genes, subtype stratification, and immune landscape implications

This study offers a detailed exploration of lung adenocarcinoma (LUAD), addressing its heterogeneity and treatment challenges through a multi-faceted analysis that includes gene expression, genetic subtyping, pathway analysis, immune assessment, and drug sensitivity. It identifies 165 genes with significant expression differences and 46 genes associated with survival, revealing insights into oxidative stress and autophagy. LUAD samples were divided into three subtypes using consensus clustering on these 46 genes, with distinct survival outcomes. Gene Set Enrichment Analysis (GSEA) on HALLMARK gene sets indicated pathway variations with survival implications. The immune landscape, analyzed using the CIBERSORT algorithm, showed different immune cell distributions across subtypes, with the first subtype exhibiting a better immune environment and survival prospects. Advanced machine learning techniques developed a risk model from a set of four genes, effectively categorizing patients into high and low-risk groups, validated through external datasets and analyses. This model linked lower risk scores to better clinical stages, with a higher mutation rate and potential immunotherapy benefits observed in the high-risk group. Drug sensitivity assessments highlighted varied treatment responses between risk groups, suggesting avenues for personalized therapy. This comprehensive analysis enhances the understanding of LUAD's molecular and clinical nuances, offering valuable insights for tailored treatment approaches.

Arsenic trioxide suppresses lung adenocarcinoma stem cell stemness by inhibiting m6A modification to promote ferroptosis

Arsenic trioxide (ATO) is well known for its inhibitory effects on cancer progression, including lung adenocarcinoma (LUAD), but the molecular mechanism remains elusive. This study aimed to investigate the roles of ATO in regulating LUAD stem cells (LASCs) and the underlying mechanisms. To induce LASCs, cells cultured in an F12 medium, containing B27, epidermal growth factor, and basic fibroblast growth factor, induced LASCs. LASCs stemness was assessed through tumor sphere formation assay, and percentages of CD133+ cells were detected by flow cytometry. The Cell Counting Kit-8 method was used to assess LASCs viability, while reactive oxygen species (ROS) and iron ion levels were quantitated by fluorescence microscopy and spectrophotometry, respectively, and total m6A levels were measured by dot blot. Additionally, LASCs mitochondrial alterations were analyzed via transmission electron microscopy. Finally, the tumorigenicity of LASCs was assessed using a cancer cell line-based xenograft model. Tumor sphere formation and CD133 expression were used to validate the successful induction of LASCs from A549 and NCI-H1975 cells. ATO significantly inhibited proliferation, reduced ZC3H13 expression and total m6A modification levels, and increased ROS and iron ion content, but repressed sphere formation and CD133 expression in LASCs. ZC3H13 overexpression or ferrostatin-1 treatment abrogated LASCs stemness inhibition caused by ATO treatment, and interference with ZC3H13 inhibited LASCs stemness. Furthermore, the promotion of LASCs ferroptosis by ATO was effectively mitigated by ZC3H13 overexpression, while interference with ZC3H13 further promoted ferroptosis. Moreover, si-ZC3H13 promoted ferroptosis and impaired stemness in LASCs, which ferrostatin-1 abrogated. Finally, ZC3H13 overexpression alleviated the inhibitory effects of ATO on LASCs tumorigenicity. Taken together, ATO treatment substantially impaired the stemness of LUAD stem cells by promoting the ferroptosis program, which was mediated by its ZC3H13 gene expression inhibition to suppress m6A medication.

Integrin β4 Regulates Cell Migration of Lung Adenocarcinoma Through FAK Signaling

The role of the integrin family in malignancy has received increasing attention. Many studies have confirmed that ITGB4 could activate multiple signal pathways and promote cell migration in various cancers. However, the regulatory role of integrin β4 (ITGB4) in lung adenocarcinoma (LUAD) is still unclear. Examination of the expression or survival analysis of ITGB4 in cells, pathological samples, and bioinformatics lung adenocarcinoma databases showed ITGB4 was highly expressed in LUAD and significantly associated with poor prognosis. Small interfering RNA and plasmids were performed to investigate the effect of changes in ITGB4 expression on lung adenocarcinoma. Focal adhesion kinase (FAK) inhibitor defactinib was used to further explore the molecular mechanism of ITGB4. The results showed depletion of ITGB4 inhibited migration and activation of FAK signaling pathways in lung adenocarcinoma cells. Moreover, increased ITGB4 expression activated FAK signaling and promoted cell migration, which can be reversed by defactinib. In addition, ITGB4 could interact with FAK in lung adenocarcinoma cells. ITGB4 may promote cell migration of lung adenocarcinoma through FAK signaling pathway and has the potential to be a biomarker for lung adenocarcinoma.

Alveolar type I cells can give rise to KRAS-induced lung adenocarcinoma

Lung adenocarcinoma (LUAD) is the most prevalent subtype of lung cancer and presents clinically with a high degree of biological heterogeneity and distinct clinical outcomes. The current paradigm of LUAD etiology posits alveolar epithelial type II (AT2) cells as the primary cell of origin, while the role of AT1 cells in LUAD oncogenesis remains unknown. Here, we examine oncogenic transformation in mouse Gram-domain containing 2 (Gramd2)+ AT1 cells via oncogenic KRASG12D. Activation of KRASG12D in AT1 cells induces multifocal LUAD, primarily of papillary histology. Furthermore, KRT8+ intermediate cell states were observed in both AT2- and AT1-derived LUAD, but SCGB3A2+, another intermediate cell marker, was primarily associated with AT1 cells, suggesting different mechanisms of tumor evolution. Collectively, our study reveals that Gramd2+ AT1 cells can serve as a cell of origin for LUAD and suggests that distinct subtypes of LUAD based on cell of origin be considered in the development of therapeutics.

Construction of a prognostic model for lung adenocarcinoma based on heat shock protein-related genes and immune analysis

Lung adenocarcinoma (LUAD) represents a prevalent form of cancer, with low early diagnosis rates and high mortality rates, posing a global health challenge. Heat shock proteins (HSPs) assume a crucial role within the tumor immune microenvironment (TME) of LUAD. Here, a collection of 97 HSP-related genes (HSPGs) was assembled based on prior literature reports, of which 36 HSPGs were differentially expressed in LUAD. In The Cancer Genome Atlas (TCGA) cohort, we constructed a prognostic model for risk stratification and prognosis prediction by integrating 13 HSPGs. In addition, the prognostic significance and predictive efficacy of the HSP-related riskscore were examined and validated in the Gene Expression Omnibus (GEO) cohort. To facilitate the clinical use of this riskscore, we also established a nomogram scale by verifying its effectiveness through different methods. In light of these outcomes, we concluded a significant correlation between HSPs and TME in LUAD, and the riskscore can be a reliable prognostic indicator. Furthermore, this study evaluated the differences in immunophenoscore, tumor immune dysfunction and exclusion score, and sensitivity to several common chemotherapy drugs among LUAD individuals in different risk groups, which may aid in clinical decision-making for immune therapy and chemotherapy in LUAD individuals.

Inhibition of HSP90 in Driver Oncogene-Defined Lung Adenocarcinoma Cell Lines: Key Proteins Underpinning Therapeutic Efficacy

The use of 90 kDa heat shock protein (HSP90) inhibition as a therapy in lung adenocarcinoma remains limited due to moderate drug efficacy, the emergence of drug resistance, and early tumor recurrence. The main objective of this research is to maximize treatment efficacy in lung adenocarcinoma by identifying key proteins underlying HSP90 inhibition according to molecular background, and to search for potential biomarkers of response to this therapeutic strategy. Inhibition of the HSP90 chaperone was evaluated in different lung adenocarcinoma cell lines representing the most relevant molecular alterations (EGFR mutations, KRAS mutations, or EML4-ALK translocation) and wild-type genes found in each tumor subtype. The proteomic technique iTRAQ was used to identify proteomic profiles and determine which biological pathways are involved in the response to HSP90 inhibition in lung adenocarcinoma. We corroborated the greater efficacy of HSP90 inhibition in EGFR mutated or EML4-ALK translocated cell lines. We identified proteins specifically and significantly deregulated after HSP90 inhibition for each molecular alteration. Two proteins, ADI1 and RRP1, showed independently deregulated molecular patterns. Functional annotation of the altered proteins suggested that apoptosis was the only pathway affected by HSP90 inhibition across all molecular subgroups. The expression of ADI1 and RRP1 could be used to monitor the correct inhibition of HSP90 in lung adenocarcinoma. In addition, proteins such as ASS1, ITCH, or UBE2L3 involved in pathways related to the inhibition of a particular molecular background could be used as potential response biomarkers, thereby improving the efficacy of this therapeutic approach to combat lung adenocarcinoma.

MLK4 promotes glucose metabolism in lung adenocarcinoma through CREB-mediated activation of phosphoenolpyruvate carboxykinase and is regulated by KLF5

MLK4, a member of the mitogen-activated protein kinase kinase kinase (MAP3K) family, has been implicated in cancer progression. However, its role in lung adenocarcinoma has not been characterized. Here, we showed that MLK4 was overexpressed in a significant subset of lung adenocarcinoma, associated with a worse prognosis, and exerted an oncogenic function in vitro and in vivo. Bioinformatics analyses of clinical datasets identified phosphoenolpyruvate carboxykinase 1 (PCK1) as a novel target of MLK4. We validated that MLK4 regulated PCK1 expression at transcriptional level, by phosphorylating the transcription factor CREB, which in turn mediated PCK1 expression. We further demonstrated that PCK1 is an oncogenic factor in lung adenocarcinoma. Given the importance of PCK1 in the regulation of cellular metabolism, we next deciphered the metabolic effects of MLK4. Metabolic and mass spectrometry analyses showed that MLK4 knockdown led to significant reduction of glycolysis and decreased levels of glycolytic pathway metabolites including phosphoenolpyruvate and lactate. Finally, the promoter analysis of MLK4 unravelled a binding site of transcription factor KLF5, which in turn, positively regulated MLK4 expression in lung adenocarcinoma. In summary, we have revealed a KLF5-MLK4-PCK1 signalling pathway involved in lung tumorigenesis and established an unusual link between MAP3K signalling and cancer metabolism.

Imaging of lung cancer

Lung cancer is the leading cause of cancer-related mortality globally. Imaging is essential in the screening, diagnosis, staging, response assessment, and surveillance of patients with lung cancer. Subtypes of lung cancer can have distinguishing imaging appearances. The most frequently used imaging modalities include chest radiography, computed tomography, magnetic resonance imaging, and positron emission tomography. Artificial intelligence algorithms and radiomics are emerging technologies with potential applications in lung cancer imaging.

Systematically analyzed molecular characteristics of lung adenocarcinoma using metabolism-related genes classification

High heterogeneity of lung adenocarcinoma (LUAD) is a major clinical challenge. This study aims to characterize the molecular features of LUAD through classification based on metabolism-related genes. A total of 500 LUAD samples from The Cancer Genome Atlas (TCGA) and 612 from Gene Expression Omnibus (GEO) were integrated with 2,753 metabolism-related genes to determine the molecular classification. Systematic bioinformatics analysis was used to conduct correlation analysis between metabolism-related classification and molecular characteristics of LUAD. LUAD patients were divided into three molecular clusters (C1-C3). Survival analysis revealed that C1 and C2 showed good and poor prognoses, respectively. Associational analysis of classification and molecular characteristics revealed that C1 was associated with low pathological stage, metabolic pathways, high metabolic process, active immune process and checkpoint, sensitive drug response, as well as a low genetic mutation. Nevertheless, C2 was associated with high pathological stage, carcinogenic pathways, low metabolic process, inactive immune signatures, resistant drug response, and frequent genetic mutation. Eventually, a classifier with 60 metabolic genes was constructed, confirming the robustness of molecular classification on LUAD. Our findings promote the understanding of LUAD molecular characteristics, and the research data may be used for providing information be helpful for clinical diagnosis and treatment.

The DDR-related gene signature with cell cycle checkpoint function predicts prognosis, immune activity, and chemoradiotherapy response in lung adenocarcinoma

BACKGROUND

As a DNA surveillance mechanism, cell cycle checkpoint has recently been discovered to be closely associated with lung adenocarcinoma (LUAD) prognosis. It is also an essential link in the process of DNA damage repair (DDR) that confers resistance to radiotherapy. Whether genes that have both functions play a more crucial role in LUAD prognosis remains unclear.

METHODS

In this study, DDR-related genes with cell cycle checkpoint function (DCGs) were selected to investigate their effects on the prognosis of LUAD. The TCGA-LUAD cohort and two GEO external validation cohorts (GSE31210 and GSE42171) were performed to construct a prognosis model based on the least absolute shrinkage and selection operator (LASSO) regression. Patients were divided into high-risk and low-risk groups based on the model. Subsequently, the multivariate COX regression was used to construct a prognostic nomogram. The ssGSEA, CIBERSORT algorithm, TIMER tool, CMap database, and IC50 of chemotherapeutic agents were used to analyze immune activity and responsiveness to chemoradiotherapy.

RESULTS

4 DCGs were selected as prognostic signatures, and patients in the high-risk group had a lower overall survival (OS). The lower infiltration levels of immune cells and the higher expression levels of immune checkpoints appeared in the high-risk group. The damage repair pathways were upregulated, and chemotherapeutic agent sensitivity was poor in the high-risk group.

CONCLUSIONS

The 4-DCGs signature prognosis model we constructed could predict the survival rate, immune activity, and chemoradiotherapy responsiveness of LUAD patients.

Immune Subtypes in LUAD Identify Novel Tumor Microenvironment Profiles With Prognostic and Therapeutic Implications

The six transcriptomic immune subtypes (ISs) (C1 - C6) were reported to have complex and different interplay between TME and cancer cells in TCGA (The Cancer Genome Atlas) pan-cancer cohort. Our study specifically explored how the consequence of interplay determines the prognosis and the response to therapy in LUAD cohorts. Clinical and molecular information of LUAD patients were from TCGA and Gene Expression Omnibus (GEO). The immune cell populations and gene/pathway enrichment analysis were performed to explore the molecular differences among the C3 IS and other ISs in the LUAD population. The proportion of C3 inflammatory IS was identified as the most common IS in both TCGA (N = 457) and GEO (N = 901) cohorts. The C3 IS was also found to be the most accurate prognostic subtype, which was associated with significantly longer OS (p <0.001) and DFS (p <0.001). The C3 IS presented higher levels of CD8 T, M1 macrophage, and myeloid dendritic cells, while lower levels of M2 macrophages and cancer-associated fibroblast cells. Moreover, the C3 subtype was enriched in the antigen process and presenting, interferon-gamma response, T cell receptor signaling, and natural killer cell-mediated cytotoxicity pathways than C1/C2. In contrast, the C1/C2 presented greater activation of pathways related to the cell cycles, DNA repair, and p53 signaling pathways. The immune-related C3 IS had a great ability to stratify the prognosis of LUAD, providing clues for further pathogenic research. This classification might help direct precision medicine screenings of LUAD patients, thus possibly improving their prognoses.

CD8+ T Cell-Associated Gene Signature Correlates With Prognosis Risk and Immunotherapy Response in Patients With Lung Adenocarcinoma

The presence of infiltrating CD8⁺ T lymphocytes in the tumor microenvironment of lung adenocarcinoma (LUAD) is correlated with improved patient prognosis, but underlying regulatory mechanisms remain unknown. To identify biomarkers to improve early diagnosis and treatment of LUAD, we downloaded 13 immune cell line-associated datasets from the GEO database. We identified CD8⁺ T cell-associated genes via weighted correlation network analysis. We constructed molecular subtypes based on CD8⁺ T cell-associated genes and constructed a multi-gene signature. We identified 252 CD8⁺ T cell-associated genes significantly enriched in immune function-related pathways and two molecular subtypes of LUAD (immune cluster 1 [IC1] and IC2) using our CD8⁺ T cell-associated gene signature. Patients with the IC2 subtype had a higher tumor mutation burden and lower immune infiltration scores, whereas those with the IC1 subtype were more sensitive to immune checkpoint inhibitors. Prioritizing the top candidate genes to construct a 10-gene signature, we validated our model using independent GSE and TCGA datasets to confirm its robustness and stable prognostic ability. Our risk model demonstrated good predictive efficacy using the Imvigor210 immunotherapy dataset. Thus, we established a novel and robust CD8⁺ T cell-associated gene signature, which could help assess prognostic risk and immunotherapy response in LUAD patients.

CircMMD_007 promotes oncogenic effects in the progression of lung adenocarcinoma through microRNA-197-3p/protein tyrosine phosphatase non-receptor type 9 axis

Circular RNAs play important roles in cancer biology. In this research, we explored the underlying function and mechanism of cirMMD_007 in lung adenocarcinoma (LC). Clinical lung adenocarcinoma samples were obtained from surgery. Bioinformatic databases were used to predict miRNAs that can potentially target circRNAs and miRNA target genes. hsa_circMMD_007, miR-197-3p, and PTPN9 mRNA expressions were investigated by qRT-PCR. Protein expressions were examined using Western blot. The proliferation abilities were assessed by Cell Counting Kit-8 assays. Wound healing cell migration assay was applied to evaluate cell migration ability. Luciferase reporter assay and rescue experiments were then performed to elucidate the underlying mechanism. We found that the expression of circMMD_007 was abnormally increased in LC. The expression of circMMD_007 was higher in advanced stages. Knockout of circMMD_007 hindered the tumorigenesis of LC in vivo and in vitro. circMMD_007 could negatively regulate the expression of miR-197-3p. PTPN9 behaved to be a molecular target of miR-197-3p. In summary, this research demonstrated that circular RNA circMMD_007 could promote the oncogenic effects in the progression of LC through miR-197-3p/PTPN9 axis.

Identification of a Four-Gene Signature Associated with the Prognosis Prediction of Lung Adenocarcinoma Based on Integrated Bioinformatics Analysis

Lung adenocarcinoma (LUAD) is often diagnosed at an advanced stage, so it is necessary to identify potential biomarkers for the early diagnosis and prognosis of LUAD. In our study, a gene co-expression network was constructed using weighted gene co-expression network analysis (WGCNA) in order to obtain the key modules and genes correlated with LUAD prognosis. Four hub genes (HLF, CHRDL1, SELENBP1, and TMEM163) were screened out using least absolute shrinkage and selection operator (LASSO)–Cox regression analysis; then, a prognostic model was established for predicting overall survival (OS) based on these four hub genes..Furthermore, the prognostic values of this four-gene signature were verified in four validation sets (GSE26939, GSE31210, GSE72094, and TCGA-LUAD) as well as in the GEPIA database. To assess the prognostic values of hub genes, receiver operating characteristic (ROC) curves were constructed and a nomogram was created. We found that a higher expression of four hub genes was associated with a lower risk of patient death. In a training set, it was demonstrated that this four-gene signature was a better prognostic factor than clinical factors such as age and stage of disease. Moreover, our results revealed that these four genes were suppressor factors of LUAD and that their high expression was associated with a lower risk of death. In summary, we demonstrated that this four-gene signature could be a potential prognostic factor for LUAD patients. These findings provide a theoretical basis for exploring potential biomarkers for LUAD prognosis prediction in the future.

Identification and Validation of a Novel Six-lncRNA-Based Prognostic Model for Lung Adenocarcinoma

Objective

This study was conducted in order to establish a long non-coding RNA (lncRNA)-based model for predicting overall survival (OS) in patients with lung adenocarcinoma (LUAD).

Methods

Original RNA-seq data of LUAD samples were extracted from The Cancer Genome Atlas (TCGA) database. Univariate Cox survival analysis was performed to select lncRNAs associated with OS. The least absolute shrinkage and selection operator (LASSO) regression analysis and multivariate Cox analysis were performed for building an OS-associated lncRNA prognostic model. Moreover, receiver operating characteristic (ROC) curves were generated to assess predictive values of the hub lncRNAs. Consequently, qRT-PCR was conducted to validate its prognostic value. The potential roles of these lncRNAs in immunotherapy and anti-angiogenic therapy were also investigated.

Results

The lncRNA-associated risk score of OS (LARSO) was established based on the LASSO coefficient of six individual lncRNAs, including CTD-2124B20.2, CTD-2168K21.1, DEPDC1-AS1, RP1-290I10.3, RP11-454K7.3, and RP11-95M5.1. Kaplan–Meier analysis revealed that LUAD patients with higher LARSO values had a shorter OS. Furthermore, a new risk score (NRS), including LARSO, stage, and N stage, could better predict the prognosis of LUAD patients compared with LARSO alone. Evaluation of the prognostic model in our cohort demonstrated that patients with higher scores had a worse prognosis. In addition, correlation analysis between these six lncRNAs and immune checkpoints or anti-angiogenic targets suggested that LUAD patients with high LARSO might not be sensitive to immunotherapy or anti-angiogenic therapy.

Conclusions

This robust six-lncRNA prognostic signature may be used as a novel and powerful prognostic biomarker for lung adenocarcinoma.

Transbronchial needle aspiration with endobronchial ultrasonography and ultrathin bronchoscopy for peripheral pulmonary lesions

BACKGROUND

Although the efficacy of lung cancer treatment has improved, it is dependent on a reliable diagnosis via bronchoscopy. Transbronchial biopsy using ultrathin bronchoscopy can help detect small peripheral pulmonary lesions (PPLs), with a high diagnostic yield. However, the diagnosis rate using forceps biopsy when the radial endobronchial ultrasonography (rEBUS) probe is adjacent to a lesion tends to be low. Transbronchial needle aspiration (TBNA) may improve the diagnostic yield from adjacent lesions. Recently, PeriView FLEX, a new TBNA needle that can be inserted into ultrathin bronchoscopes, has become available. We examined whether TBNA with PeriView FLEX and forceps biopsy improved adjacent lesion diagnosis when using ultrathin bronchoscopes.

METHODS

We retrospectively examined 51 consecutive patients who underwent TBNA and forceps biopsy using ultrathin bronchoscopes under rEBUS for small PPLs at the Hakodate Goryoukaku Hospital between November 2019 and August 2020. The histological diagnosis rate using TBNA and forceps biopsy, TBNA alone, or forceps biopsy alone was compared between cases where the rEBUS probe was "Within" and "Adjacent To" the lesions.

RESULTS

The diagnosis rate using TBNA and forceps biopsy was 86.3% (95.7% vs. 78.6%; p = 0.08) for all lesions (Within cases vs. Adjacent To cases). The corresponding rate using TBNA alone was 68.6% (69.6% vs. 67.9%; p = 0.57), and that using forceps biopsy alone was 72.5% (91.3% vs. 57.1%; p = 0.0067).

CONCLUSIONS

Forceps biopsy with TBNA during ultrathin bronchoscopy for small PPLs improved the diagnostic yield when lesions were adjacent to the rEBUS probe.

Fe3O4 magnetic nanoparticle-enhanced radiotherapy for lung adenocarcinoma via delivery of siBIRC5 and AS-ODN

Background

Radiotherapy is the mainstay treatment for lung adenocarcinoma, yet remains highly susceptible to resistance. Fe₃O₄ magnetic nanoparticles (MNPs) possess the ability to induce biological therapeutic effects. Herein, the current study set out to explore the effects of Fe₃O₄ MNPs on radiosensitivity of lung adenocarcinoma cells.

Methods

Fe₃O₄ MNPs loaded with both negatively-charged small interfering RNA against baculoviral IAP repeat containing 5 (siBIRC5) and oligodeoxynucleotide antisense (AS-ODN) to generate co-delivery NPs, followed by evaluation. Gel retardation assay was further performed to determine the binding ability of Fe₃O₄ MNPs to AS-ODN/siBIRC5. The radiosensitizing effect of NPs on lung adenocarcinoma cells was determined in the absence or the presence of NPs or radiotherapy. A549 and H460 tumor-bearing mice were established, where tumor tissues were subjected to immunohistochemistry.

Results

NPs were successfully prepared and characterized. BIRC5 expression levels were augmented in tissues of lung cancer patients. Fe₃O₄ MNPs enhanced the uptake of siBIRC5 and AS-ODN by lung adenocarcinoma cells. The presence of NPs under magnetic field reduced the BIRC5 expression and elevated the DR5 expression in lung adenocarcinoma cells. Lung adenocarcinoma cells treated with NPs exhibited inhibited tumor cell migration and increased DNA damage. After magnetic field treatment, tumors were better suppressed in the tumor-bearing mice treated with NPs, followed by radiotherapy.

Conclusion

Findings obtained in our study indicated that Fe₃O₄ MNPs-targeted delivery of siBIRC5 and AS-ODN enhances radiosensitivity, providing an innovative solution for the current clinically existing lung adenocarcinoma patients with radiotherapy resistance with a low risk of toxicity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02971-7.

De Novo Nano-Erythrocyte Structurally Braced by Biomimetic Au(I)-peptide Skeleton for MDM2/MDMX Predation toward Augmented Pulmonary Adenocarcinoma Immunotherapy

In nature, cells rely on a structural framework called the "cytoskeleton" to maintain their shape and polarity. Based on this, herein a new class of cell-mimicking nanomedicine using bionic skeletons constituted by the oligomeric Au(I)-peptide complex is developed. The peptide function of degrading pathological MDM2 and MDMX is used to synthesize an oligomeric Au(I)-PMIV precursor capable of self-assembling into a clustered spherical bionic skeleton. Through coating by erythrocyte membrane, an erythrocyte-mimicking nano-cell (Nery-PMIV) is developed with depressed macrophage uptakes, increased colloidal stability, and prolonged blood circulation. Nery-PMIV potently restores p53 and p73 in vitro and in vivo by degrading MDM2/MDMX. More importantly, Nery-PMIV effectively augments antitumor immunity elicited by anti-PD1 therapy in a murine orthotopic allograft model for LUAD and a humanized patient-derived xenograft (PDX) mouse model for LUAD, while maintaining a favorable safety profile. Taken together, this work not only presents evidence showing that MDM2/MDMX degradation is a potentially viable therapeutic paradigm to synergize anti-PD1 immunotherapy toward LUAD carrying wild-type p53; it also suggests that cell-mimicking nanoparticles with applicable bionic skeletons hold tremendous promise in offering new therapies to revolutionize nanomedicine in the treatment of a myriad of human diseases.

EGFR and KRAS Mutations in Lung Parenchyma of Subjects With EGFR/KRAS Wild-Type Lung Adenocarcinoma

The acquisition of driver mutations in non-tumoral cells appears to be very important during the carcinogenesis of adenocarcinoma (ADC). Recent studies suggest that cancer-related mutations may not necessarily be present only in malignant cells, but also in histologically “healthy cells”.

Objective: to demonstrate the presence of EGFR or KRAS mutations in non-tumoral lung cells in subjects with ADC and negative mutational status.

Results: mutations in EGFR or KRAS oncogenes were identified in the normal lung in 9.7% of the subjects. Exon 21 substitution L858R in EGFR was detected in two cases while the exon 19 deletion E746-A750 in the EGFR, the G12C and G12D substitutions in the KRAS were detected once. One patient presented three different mutations in the normal lung parenchyma (EGFR_L858R, KRAS_G12C and KRAS_G12D). The negative-mutation status of the tumor and the mutations detected in the “normal lung” were confirmed using highly sensitive and specific TaqMan PCR (CAST-PCR). No differences were found in terms of progression, progression-free survival or overall survival during the 18 months follow-up.

Conclusions: These results confirm the presence of driver mutations in the histologically normal lung parenchyma cells in the absence of mutations coexisting with the primary tumor.

Identification of CXCL13/CXCR5 axis's crucial and complex effect in human lung adenocarcinoma

Immune escape and low response to immunotherapy are crucial challenges in present lung cancer treatment. In this study, we constructed a new immune-related classifier based on CXCL13/CXCR5, an important tumor microenvironment component and strongly related with the formation of tertiary lymphoid structures (TLSs) in tumor microenvironment. With the classifier, we divided patients into two main clusters and each cluster was further divided into subcluster (A1, A2, B1, B2, B3). In the later analysis, we noticed that patients in subcluster B3 had a distinct advantage over patients in A1 in survival time and immune infiltration, suggesting a more favorable response to immunotherapy. Moreover, we demonstrated the genetic and epigenetic regulation related to the subclusters and recovered four key differentially expressed genes (ERBB4, GRIN2A, IL2RA, CCND2). With several experiments, we verified the unique role of CCND2 in tumor metastasis and T cell apoptosis. Overexpressing CCND2 could significantly impair cancer cell abilities of migration and invasion and downregulate PD-1/PD-L1 signaling, which may be the cause of T cell apoptosis reduction. In the end, we constructed a regression risk model that could successfully predict ICI response. To sum up, our study established new stratification models that can successfully predict patient survival and response to ICI. And using integrative analysis of multi-omics data, four key DEGs were noticed, and CCND2, one of the four genes, was identified as a potential treatment target because of its effect in tumor metastasis and T cell apoptosis.

CYP4B1 is a prognostic biomarker and potential therapeutic target in lung adenocarcinoma

CYP4B1 belongs to the mammalian CYP4 enzyme family and is predominantly expressed in the lungs of humans. It is responsible for the oxidative metabolism of a wide range of endogenous compounds and xenobiotics. In this study, using data from The Cancer Genome Atlas (TCGA) project and the Gene Expression Omnibus (GEO) database, a secondary analysis was performed to explore the expression profile of CYP4B1, as well as its prognostic value in patients with lung adenocarcinoma (LUAD). Based on the obtained results, a significantly decreased CYP4B1 expression was discovered in patients with LUAD when compared with their normal counterparts (p<0.05), and was linked to age younger than 65 years (p = 0.0041), history of pharmaceutical (p = 0.0127) and radiation (p = 0.0340) therapy, mutations in KRAS/EGFR/ALK (p = 0.0239), and living status of dead (p = 0.0026). Survival analysis indicated that the low CYP4B1 expression was an independent prognostic indicator of shorter survival in terms of overall survival (OS) and recurrence-free survival (RFS) in patients with LUAD. The copy number alterations (CNAs) and sites of cg23440155 and cg23414387 hypermethylation might contribute to the decreased CYP4B1 expression. Gene set enrichment analysis (GSEA) suggested that CYP4B1 might act as an oncogene in LUAD by preventing biological metabolism pathways of exogenous and endogenous compounds and enhancing DNA replication and cell cycle activities. In conclusion, CYP4B1 expression may serve as a valuable independent prognostic biomarker and a potential therapeutic target in patients with LUAD.

Real-World Utilization of Biomarker Testing for Patients with Advanced Non-Small Cell Lung Cancer in a Tertiary Referral Center and Referring Hospitals

The continued introduction of biomarkers and innovative testing methods makes already complex diagnosis in patients with stage IV non-small-cell lung cancer (NSCLC) even more complex. This study primarily analyzed variations in biomarker testing in clinical practice in patients referred to a comprehensive cancer center in the Netherlands. The secondary aim was to compare the cost of biomarker testing with the cost of whole-genome sequencing. The cohort included 102 stage IV NSCLC patients who received biomarker testing in 2017 or 2018 at the comprehensive cancer center. The complete biomarker testing history of the cohort was identified using linked data from the comprehensive cancer center and the nationwide network and registry of histopathology and cytopathology in the Netherlands. Unique biomarker-test combinations, costs, turnaround times, and test utilization were examined. The results indicate substantial variation in test utilization and sequences. The mean cost per patient of biomarker testing was 2259.92 ± 1217.10 USD, or 1881.23 ± 1013.15 EUR. Targeted gene panels were most frequently conducted, followed by IHC analysis for programmed cell death protein ligand 1. Typically, the most common biomarkers were assessed within the first tests, and emerging biomarkers were tested further down the test sequence. At the cost of current biomarker testing, replacing current testing with whole-genome sequencing would have led to cost-savings in only two patients (2%).

Sedation with fentanyl and midazolam without oropharyngeal anesthesia compared with sedation with pethidine and midazolam with oropharyngeal anesthesia in ultrathin bronchoscopy for peripheral lung lesions

BACKGROUND

In advanced lung cancer, precision medicine requires repeated biopsies via bronchoscopy at therapy change. Since bronchoscopies are often stressful for patients, sedation using both fentanyl and midazolam is recommended in Europe and America. In Japan, bronchoscopies are generally orally performed under midazolam and oropharyngeal anesthesia. Nasal intubation creates a physiological route to the trachea, causing less irritation to the pharynx than intubation via the oral cavity; however, the necessity of oropharyngeal anesthesia remains unclear. We aimed to compare the safety, patient discomfort, and diagnostic rates for oropharyngeal anesthesia and sedation with pethidine and midazolam (Group A) and sedation with midazolam and fentanyl without oropharyngeal anesthesia (Group B) for ultrathin bronchoscopy of peripheral pulmonary lesions (PPLs) via nasal intubation.

METHODS

We retrospectively reviewed 74 consecutive potential lung cancer patients who underwent ultrathin bronchoscopies at the Hakodate Goryoukaku Hospital between July 2019 and June 2020. We reviewed the following: diagnostic rates; cumulative doses of lidocaine, midazolam, and fentanyl; hemodynamic changes; procedural complications in both groups. Pharyngeal anesthesia in group A was administered by spraying 2% (w/v) lidocaine into the pharynx. The chi-squared test was used for statistical analyses.

RESULTS

There were no significant changes in hemodynamic parameters and complications. The mean level of discomfort for bronchoscopic examinations was significantly lower in Group B (2.39 vs. 1.64; P = 0.014), with no significant inter-group difference in the diagnostic yields for PPLs (63.0% vs. 71.4%; P = 0.46).

CONCLUSIONS

Our findings indicate the advantages of sedation with fentanyl and midazolam without oropharyngeal anesthesia for ultrathin bronchoscopy through nasal intubation.

Serum microRNA expression profiling revealing potential diagnostic biomarkers for lung adenocarcinoma

Background

Recent studies have demonstrated that microRNAs (miRNAs) in the blood circulation can serve as promising diagnostic markers for cancers. This four-stage study aimed at finding serum miRNAs as potential biomarkers for lung adenocarcinoma (LA) diagnosis.

Methods

The study was carried out between 2016 and 2017. The Exiqon miRNA qPCR panel (3 LA vs. 1 normal control [NC] pooled serum samples) was used for initial screening to acquire miRNA profiles. Thirty-five dysregulated miRNAs were further evaluated in the training (24 LA vs. 24 NCs) and testing stages (110 LA vs. 110 NCs) using quantitative real-time polymerase chain reaction assays.

Results

Four serum miRNAs (miR-133a-3p, miR-584-5p, miR-10b-5p, and miR-221-3p) were significantly overexpressed in LA patients compared with NCs. The diagnostic value of the four-miRNA panel was validated by an external cohort (36 LA vs. 36 NCs). The areas under the receiver operating characteristic curve of the four-miRNA panel in the training, testing, and external validation stages were 0.734, 0.803, and 0.894 respectively. Meanwhile, the expression level of miR-221-3p was much higher in LA tumor samples than that in the adjacent normal tissues (19 LA vs. 19 NCs). The expression level of miR-10b-5p was also elevated in the serum-derived exosomes samples (18 LA vs. 18 NCs). The expression of miR-133a-3p, miR-584-5p, and miR-10b-5p was significantly elevated in LA patients with epidermal growth factor receptor mutation compared with NCs.

Conclusion

The study established a four-miRNA signature in serum that could improve the diagnostic capability of LA.

A gene-based survival score for lung adenocarcinoma by multiple transcriptional datasets analysis

Background

Lung adenocarcinoma (LUAD) remains a crucial factor endangering human health. Gene-based clinical predictions could be of great help for cancer intervention strategies. Here, we tried to build a gene-based survival score (SS) for LUAD via analyzing multiple transcriptional datasets.

Methods

We first acquired differentially expressed genes between tumors and normal tissues from intersections of four LUAD datasets. Next, survival-related genes were preliminarily unscrambled by univariate Cox regression and further filtrated by LASSO regression. Then, we applied PCA to establish a comprehensive SS based on survival-related genes. Subsequently, we applied four independent LUAD datasets to evaluate prognostic prediction of SS. Moreover, we explored associations between SS and clinicopathological features. Furthermore, we assessed independent predictive value of SS by multivariate Cox analysis and then built prognostic models based on clinical stage and SS. Finally, we performed pathway enrichments analysis and investigated immune checkpoints expression underlying SS in four datasets.

Results

We established a 13 gene-based SS, which could precisely predict OS and PFS of LUAD. Close relations were elicited between SS and canonical malignant indictors. Furthermore, SS could serve as an independent risk factor for OS and PFS. Besides, the predictive efficacies of prognostic models were also reasonable (C-indexes: OS, 0.7; PFS, 0.7). Finally, we demonstrated enhanced cell proliferation and immune escape might account for high clinical risk of SS.

Conclusions

We built a 13 gene-based SS for prognostic prediction of LUAD, which exhibited wide applicability and could contribute to LUAD management.

Identification of Mutations Related to Cisplatin-Resistance and Prognosis of Patients With Lung Adenocarcinoma

Background: Lung adenocarcinoma (LUAD) is the most common histologic type of non-small cell lung cancer (NSCLC; approximately 60%), and platinum-based chemotherapy is the cornerstone of the treatment for patients with LUAD. However, a considerable number of patients experience tumor recurrence after developing cisplatin (cis-diamminedichloroplatinum(II) or CDDP) resistance. Therefore, it is particularly important to screen primary CDDP-resistant LUAD patient populations, which can maximize the clinical benefits for these patients. Methods: Data for 61 LUAD cell lines were downloaded from the Genomics of Drug Sensitivity in Cancer (GDSC) database to screen for mutations related to CDDP susceptibility, and we conducted whole-exome sequencing (WES) of tumors from 45 LUAD patients from Zhujiang Hospital of Southern Medical University. Subsequently, the clinical prognostic value of these mutations was verified by using The Cancer Genome Atlas (TCGA)-LUAD cohort and our cohort (n = 45). Results: Based on drug sensitivity data for the GDSC-LUAD cell lines and survival analysis of the cohorts TCGA-LUAD and Local-LUAD, we found only one gene (GREB1) with mutations related to decreased CDDP sensitivity as well as worse overall survival (OS) and progression-free survival (PFS) [OS: log-rank p = 0.038, hazard ratio (HR; 95% confidence interval (95% CI)): 2.19 (0.73-6.55); PFS: log-rank p = 0.001; HR: 4.65, 95% CI: 1.18-18.37]. The GREB1-mutant (GREB1-MT) group had a higher frequency of gene mutations. Additionally, gene set enrichment analysis (GSEA) and single-sample GSEA (ssGSEA) suggested reduced accumulation of intracellular drugs in the GREB1-MT group, in addition to increased drug efflux and enhanced DNA damage repair and intracellular detoxification. Conclusion: This study found that GREB1 mutations may mediate the primary resistance and clinical prognosis of LUAD patients undergoing treatment with CDDP. Further functional analysis showed that GREB1 mutations are related to the known mechanism of CDDP resistance. These results suggest that GREB1 mutations are potential biomarkers for screening of CDDP resistance among LUAD patients.

[Mechanism and Research Progress of Microbiome in the Development of Lung Cancer]

肺癌是我国最常见的、预后较差的恶性肿瘤之一，大多数患者确诊时即为晚期。有研究表明肺癌患者的微生态特征有别于健康人群，呼吸道的微生物可以通过多种机制影响肺癌的发生发展。近年来微生物组学与疾病相关性研究已成为继人类基因组计划又一研究热点，然而目前有关肺癌与呼吸道微生物组特征的研究相对较少，因此，需要更深入地探讨肺癌与微生物菌群间的潜在联系，通过研究呼吸道微生物在肺癌发生发展中的作用机制，以期在为肺癌的临床诊治、预后评估提供更明确的科学依据。本文对目前关于微生物菌群与肺癌相关研究进行综述，并为临床上诊断与治疗肺癌提供新的思路。

A ten-gene signature-based risk assessment model predicts the prognosis of lung adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is a major cause of cancer death. Therefore, identifying potential prognostic risk factors is critical to improve the survival of patients with LUAD.

Methods

Here, relevant datasets were downloaded from TCGA and GEO databases to screen the differentially expressed genes (DEGs). Univariate Cox analysis, LASSO regression analysis and multivariate Cox analysis were conducted on the DEGs combined with TCGA clinical data, and finally a risk assessment model based on 10 feature genes was constructed.

Results

The prognosis of patients was evaluated after the patients were grouped based on the median risk score and the results showed that the survival time of patients in the high-risk group was significantly shorter than that in the low-risk group. ROC analysis showed that the AUC values of the 1, 3, 5-year survival were 0.753, 0.724, and 0.73, respectively, indicating that the model was precise in predicting the prognosis, which was also verified in the external dataset GSE72094. In addition, a significant correlation was found between the risk score and the clinical stages of LUAD, that is, a later stage always corresponded to a higher risk score. Then, we performed survival analysis on the 10 feature genes independently in the TCGA-LUAD dataset through the GEPIA database, finding that the high expression of 6 genes (COL5A2, PLEK2, BAIAP2L2, S100P, ZIC2, SFXN1) was associated with the poor prognosis of LUAD patients.

Conclusion

To sum, this study established a 10-gene risk assessment model and further evaluated its value in predicting LUAD prognosis, which provided a new method for the prognosis prediction of LUAD.

Gene expression-based clinical predictions in lung adenocarcinoma

Mining disease-related genes contributes momentously to handling lung adenocarcinoma (LUAD). But genetic complexity and tumor heterogeneity severely get in the way. Fortunately, new light has been shed by dramatic progress of bioinformatic technology in the past decades. In this research, we investigated relationships between gene expression and clinical features of LUAD via integrative bioinformatic analysis. First, we applied limma and DESeq2 packages to analyze differentially expressed genes (DEGs) of LUAD from GEO database and TCGA project (tumor tissues versus normal tissues), and acquired 180 down-regulated DEGs and 52 up-regulated DEGs. Then, we investigated genetic and biological assignment of theses DEGs by Bioconductor packages and STRING database. We found these DEGs were distributed dispersedly among chromosomes, enriched observably in extracellular matrix-related processes, and weighted hierarchically in interaction network. Finally, we established DEGs-based statistical models for evaluating TNM stage and survival status of LUAD. And these models (logistic regression models for TNM parameter and Cox regression models for survival probability) all possessed fine predictive efficacy (C-indexes: T, 0.740; N, 0.687; M, 0.823; overall survival, 0.678; progression-free survival, 0.611). In summary, we have successfully established gene expression-based models for assessing clinical characteristics of LUAD, which will assist its pathogenesis investigation and clinical intervention.

Silencing of long non-coding RNA SOX21-AS1 inhibits lung adenocarcinoma invasion and migration by impairing TSPAN8 via transcription factor GATA6

Here, we revealed the novel role of long non-coding RNAs (lncRNAs) SOX21 antisense RNA 1 (SOX21-AS1)/TSPAN8/GATA6 in progression of lung adenocarcinoma. SOX21-AS1 expression was quantified in lung adenocarcinoma tissues and cells by RT-qPCR. Then, gain- and loss-of-function experiments were conducted in lung adenocarcinoma cells. Expression of GATA6, TSPAN8 and extracellular signal-regulated kinase (ERK) signaling pathway-related genes was determined in lung adenocarcinoma cells by western blot analysis. The interaction and relationship among SOX21-AS1, GATA6 and TSPAN8 were predicted and verified respectively by RNA pull down, RIP, ChIP, and dual-luciferase reporter assays. Next, lung adenocarcinoma cell proliferation, colony formation, invasion and migration were assessed by 5-ethynyl-2'-deoxyuridine staining, colony formation assay and Transwell assay. Xenograft tumors were established in nude mice and the tumor growth was observed and recorded. SOX21-AS1 was observed to be highly expressed in lung adenocarcinoma tissues. The overexpression of SOX21-AS1, GATA6 or TSPAN8 obviously enhanced cell biological functions in lung adenocarcinoma. Meanwhile, SOX21-AS1 interacted with GATA6 which bound to TSPAN8 promoter and promoted TSPAN8 expression, which further enhanced cell colony formation, proliferation and invasion, and also activated ERK signaling pathway. Silencing of SOX21-AS1 and inhibiting its binding to GATA6 downregulate TSPAN8 and thereby exert anti-oncogenic effects in lung adenocarcinoma.

Pulmonary enteric adenocarcinoma: a literature review

Pulmonary enteric adenocarcinoma (PEAC) is an extremely rare type of non-small cell lung cancer (NSCLC) with a histologic pattern that mimics metastatic colorectal cancer (MCC). The main clinical symptoms in PEAC patients are dyspnoea, coughing, hemoptysis, and chest and back pain. The first article about PEAC appeared in 1991 in the form of a case report. As a variant of invasive lung carcinoma, only a small number of case reports and clinical research studies have been carried out, and the only one guidance on diagnosis and treatment is the WHO Tumor Classification book. It is important for doctors to distinguish PEAC from MCC to extend survival time and improve the quality of life. We reviewed the existing literature regarding the diagnosis, treatment, and prognosis of PEAC to provide some valuable clinical references.

Support Vector Machine for Lung Adenocarcinoma Staging Through Variant Pathways

Lung adenocarcinoma (LUAD) is one of the most common malignant tumors. How to effectively diagnose LUAD at an early stage and make an accurate judgement of the occurrence and progression of LUAD are still the focus of current research. Support vector machine (SVM) is one of the most effective methods for diagnosing LUAD of different stages. The study aimed to explore the dynamic change of differentially expressed genes (DEGs) in different stages of LUAD, and to assess the risk of LUAD through DEGs enriched pathways and establish a diagnostic model based on SVM method. Based on TMN stages and gene expression profiles of 517 samples in TCGA-LUAD database, coefficient of variation (CV) combined with one-way analysis of variance (ANOVA) were used to screen out feature genes in different TMN stages after data standardization. Unsupervised clustering analysis was conducted on samples and feature genes. The feature genes were analyzed by Pearson correlation coefficient to construct a co-expression network. Fisher exact test was conducted to verify the most enriched pathways, and the variation of each pathway in different stages was analyzed. SVM networks were trained and ROC curves were drawn based on the predicted results so as to evaluate the predictive effectiveness of the SVM model. Unsupervised hierarchical clustering analysis results showed that almost all the samples in stage III/IV were clustered together, while samples in stage I/II were clustered together. The correlation of feature genes in different stages was different. In addition, with the increase of malignant degree of lung cancer, the average shortest path of the network gradually increased, while the closeness centrality gradually decreased. Finally, four feature pathways that could distinguish different stages of LUAD were obtained and the ability was tested by the SVM model with an accuracy of 91%. Functional level differences were quantified based on the expression of feature genes in lung cancer patients of different stages, so as to help the diagnosis and prediction of lung cancer. The accuracy of our model in differentiating between stage I/II and stage III/IV could reach 91%.

Epididymal protein 3A is upregulated and promotes cell proliferation in non-small cell lung cancer

Lung cancer is one of the most common cancer types and a major contributor to cancer-associated mortalities worldwide. The aim of the present study was to investigate the function of the epididymal protein 3A (EDDM3A) in non-small cell lung cancer (NSCLC). Data from patients with NSCLC were retrieved from The Cancer Genome Atlas and analyzed, and the differences in EDDM3A expression level between 30 NSCLC tissues and matched adjacent non-tumor tissues (>5 cm) were assessed via tissue microarray analysis. It was revealed that, compared with adjacent non-tumor tissues, EDDM3A expression was significantly increased in NSCLC tissues (P=4.19×10⁻²). To knock down EDDM3A expression in a human NSCLC cell line, lentivirus-mediated short hairpin RNAs (shRNAs) were used, and the knockdown efficiency was assessed via reverse transcription-quantitative PCR and western blotting. Moreover, cell proliferation was evaluated with an MTT assay and Celigo imaging cytometry. In addition, cell apoptosis was detected by Annexin V staining. It was demonstrated that knockdown of EDDM3A inhibited the proliferation of A549 cells. Furthermore, compared with the control group, the apoptotic rate of the EDDM3A-shRNA group was significantly higher. Collectively, the present results indicate the potential role of EDDM3A in NSCL and suggest that EDDM3A may represent a potent therapeutic target for treating patients with NSCLC.

Comparison of ultrathin bronchoscopy with conventional bronchoscopy for the diagnosis of peripheral lung lesions without virtual bronchial navigation

BACKGROUND

For the precise management of advanced lung cancers, bronchoscopy with a high diagnostic yield and abundant tumor specimens are required. In recent years, new devices and techniques have been rapidly developed, including the endobronchial ultrasound (EBUS) using a guide sheath, virtual bronchoscopic navigation (VBN), and ultra-thin bronchoscope (UTB), for the diagnosis of peripheral pulmonary lesions (PPLs). These techniques increase the diagnostic yield for PPL, thus requiring fewer biopsy specimens. VBN is generally not available at the city hospitals in Japan. In this study, using fluoroscopy without VBN, we studied whether the histologic diagnostic yield of radial EBUS for PPLs would be higher using a UTB (without guide sheath) or conventional bronchoscope (CB) (with guide sheath).

METHODS

We retrospectively reviewed consecutive patients with suspected lung cancer who underwent bronchoscopy at the Hakodate Goryoukaku Hospital from April 2017 to March 2019. We analyzed 168 patients-102 using UTB and 66 using CB.

RESULTS

The diagnostic yields for PPL were significantly higher in the UTB group than in the CB group (74.5% vs. 59.1%; P = 0.04). The median examination time was significantly longer in the UTB group than in the CB group (24 vs. 20 min; P = 0.01). There were no statistically significant differences in the complication rate between the UTB and CB groups (3.9% vs. 3.0%; P = 0.69).

CONCLUSIONS

UTB had a significantly higher tissue diagnostic yield than CB, without the use of VBN.

Intratumor Heterogeneity in Early Lung Adenocarcinoma

Lung cancer is one of the deadliest diseases in the world and is the leading cause of cancer-related deaths. Among the histological types, adenocarcinoma is the most common, and it is characterized by a high degree of heterogeneity at many levels including clinical, behavioral, cellular and molecular. While most lung cancers are known for their aggressive behavior, up to 18.5% of lung cancers detected by CT screening are indolent and put patients at risk for overdiagnosis and overtreatment. The cellular and molecular underpinnings of tumor behavior remain largely unknown. In the recent years, the study of intratumor heterogeneity has become an attractive strategy to understand tumor progression. This review will summarize some of the current known determinants of lung adenocarcinoma behavior and discuss recent efforts to dissect its intratumor heterogeneity.

A new immune signature for survival prediction and immune checkpoint molecules in lung adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is the most frequent subtype of lung cancer. The prognostic signature could be reliable to stratify LUAD patients according to risk, which helps the management of the systematic treatments. In this study, a systematic and reliable immune signature was performed to estimate the prognostic stratification in LUAD.

Methods

The profiles of immune-related genes for patients with LUAD were used as one TCGA training set: n = 494, other validation set 1: n = 226 and validation set 2: n = 398. Univariate Cox survival analysis was used to identify the candidate immune-related genes from each cohort. Then, the immune signature was developed and validated in the training and validation sets.

Results

In this study, functional analysis showed that immune-related genes involved in immune regulation and MAPK signaling pathway. A prognostic signature based on 10 immune-related genes was established in the training set and patients were divided into high-risk and low-risk groups. Our 10 immune-related gene signature was significantly related to worse survival, especially during early-stage tumors. Further stratification analyses revealed that this 10 immune-related gene signature was still an effective tool for predicting prognosis in smoking or nonsmoking patients, patients with KRAS mutation or KRAS wild-type, and patients with EGFR mutation or EGFR wild-type. Our signature was negatively correlated with B cell, CD4+ T cell, CD8+ T cell, neutrophil, dendritic cell (DC), and macrophage immune infiltration, and immune checkpoint molecules PD-1 and CTLA-4 (P < 0.05).

Conclusions

These findings suggested that our signature was a promising biomarker for prognosis prediction and can facilitate the management of immunotherapy in LUAD.

CCR9 Promotes Migration and Invasion of Lung Adenocarcinoma Cancer Stem Cells

Aim: CC chemokine receptor 9 (CCR9) interacts with its exclusive ligand CCL25, resulting in promoting tumor progression and metastasis. However, the effect and mechanisms of CCR9 on lung adenocarcinoma distant metastasis remain largely unknown. To preliminary clarify the underlying mechanisms, we investigate the correlation between CCR9 and ALDH1A1⁺cancer stem cells (CSCs), as well as the effect of CCR9 on the migration and invasion of CSCs. Methods: Immunohistochemistry was performed to detect the expression of CCR9 in lung adenocarcinoma tissues. The correlations of CCR9 with distant metastasis and overall survival were investigated. Serial paraffin-embedded tissue blocks were used to detect ALDH1A1⁺CSCs expression. The correlations between CCR9 expression and ALDH1A1⁺CSCs were evaluated. We further studied the effect of CCR9/CCL25 on the migration and invasion of CSCs using transwell assays. Results: There were positive correlations between CCR9 expression and distant metastasis, as well as poor overall survival. Patients with high CCR9 expression were more likely to develop distant metastasis and demonstrated poorer overall survival than patients with low CCR9 expression. In addition, there was positive correlation between the expression of CCR9 and ALDH1A1 in the same tumor microenvironment. ALDH^high CSCs demonstrated enhanced expression of CCR9 than ALDH^low cells. Further transwell assays demonstrated that the numbers of CSCs migrated or invaded in response to CCL25 were more than that without CCL25 stimulation. Additional application of anti-CCR9 antibody reversed the CCL25-induced migration and invasion of CSCs. Conclusions: In summary, our study demonstrated that CCR9/CCL25 promoted the migration and invasion of CSCs, which might contribute to distant metastasis and poor overall survival. Our findings provided evidence that CCR9/CCL25 could be used as novel therapeutic targets for lung adenocarcinoma.

[Research Progress of Treg/Th17 in the Treatment of Chronic Obstructive Pulmonary Disease with Lung Cancer]

慢性阻塞性肺疾病（chronic obstructive pulmonary disease, COPD）和肺癌为全球性高发病率、高死亡率疾病，严重增加社会经济负担。烟雾暴露、遗传易感性和慢性炎症等是二者发病的共同易感因素。目前异常炎症免疫反应在两种疾病的发生、发展中均有作用，在免疫应答过程中逐渐产生有利于血管生成和免疫抑制的肿瘤微环境（tumor microenvironment, TME），最终使肿瘤细胞发生免疫逃逸，导致肿瘤形成。本文就COPD合并肺癌的现状以及异常免疫应答尤其是Treg/Th17与其发生、发展关系方面做一个简要综述。

Overexpression of eIF3D in Lung Adenocarcinoma Is a New Independent Prognostic Marker of Poor Survival

The eukaryotic initiation factor 3 (eIF3) is the largest and most complex translation initiation factor in mammalian cells. It consists of 13 subunits and among which several were implicated to have significant prognostic effects on multiple human cancer entities. To examine the expression profiles of eIF3 subunits and determine their prognostic value in patients with lung adenocarcinoma (LUAD), the genomic data, survival data, and related clinical information were obtained from The Cancer Genome Atlas (TCGA) project for a secondary analysis. The results showed that among ten aberrantly expressed eIF3 subunits in tumours compared with adjacent normal counterparts (p < 0.05), only upregulated eIF3D could predict poor overall survival (OS) outcome independent of multiple clinicopathological parameters (HR = 2.043, 95% CI: 1.132-3.689, p = 0.018). Chi-square analysis revealed that the highly expressed eIF3D group had larger ratios of patients with advanced pathological stage (68/40 vs. 184/206, p = 0.0046), residual tumour (13/4 vs. 163/176, p = 0.0257), and targeted molecular therapy (85/65 vs. 138/164, p = 0.0357). In silico analysis demonstrated that the altered expression of eIF3D was at least regulated by both copy number alterations (CNAs) and the hypomethylation of cg14297023 site. In conclusion, high eIF3D expression might serve as a valuable independent prognostic indicator of shorter OS in patients with LUAD.

Multiple-line Chemotherapy and Tyrosine Kinase Inhibitor Treatment in Patients with Advanced Lung Cancer

AIM

To analyse the clinical outcomes of patients with lung cancer treated with first and multiple-line chemotherapy and tyrosine kinase inhibitor (TKI).

PATIENTS & METHODS

The present study included a total of 89 patients of whom lung cancer was histologically confirmed between July 2016 and September 2017. Patients' demographics, chemotherapy/TKI treatment details and clinical outcomes were retrieved. The progression-free survivals (PFS) after first-line and multiple-line treatments were evaluated using Kaplan-Meier analysis with log-rank test. Risk factors for progressive disease (PD) were identified using Cox multivariate regression model.

RESULTS

A total of 50 males and 39 females were enrolled. About 90% of the tumors were histologically classified as adenocarcinoma, and 77/89 cases (86.5%) were at TNM stage IV. The median PFS for the first-line treatment was 6.17 months. After first-line treatment, more favourable PFS was observed in patients who had prior surgery of lung cancer (P = 0.002). Multivariate analysis showed that patients who had received no prior surgical treatment for lung cancer were at higher risk of PD (OR, 4.311; 95% CI, 1.836 to 10.120; P = 0.0008). Besides, in patients with driver mutations, those who received no TKI treatment were under higher risk of PD compared to those who had been treated with TKI (OR, 4.876; 95% CI, 1.877 to 12.666; P = 0.0011). The median PFS for the multiple-line treatment was 24.67 months. After multiple-line treatments, favourable PFS was associated with tumor histological types of adenocarcinoma (P = 0.041), genetic lesions at exon 19 of EGFR (P = 0.001) and fourth-line treatment (P = 0.001). Risk factors for PD after multiple-line treatments were no prior surgery for lung cancer (OR, 3.335; 95% CI, 1.158 to 9.605; P = 0.0256), no TKI use in multiple-line treatment (OR, 10.095; 95% CI, 2.405 to 42.378; P = 0.0016), and being treated by first-line treatment alone (OR, 30.421; 95% CI, 4.813 to 192.269; P = 0.0003).

CONCLUSION

The present study demonstrated the benefits of TKI in patients with advanced lung cancer, providing insights into the refinement of the management strategy.

BATF acts as an oncogene in non-small cell lung cancer

One of the main causes of cancer incidence and mortality worldwide is lung cancer. This study focused on the function of basic leucine zipper ATF-like transcription factor (BATF) in non-small cell lung cancer (NSCLC). Using NSCLC patient data from The Cancer Genome Atlas, the present study demonstrated that BATF expression in NSCLC tissues was significantly higher compared with that in adjacent non-tumor tissues (P=6.56×10⁻⁶). Lentivirus-mediated short hairpin RNA (shRNA) was used to knock down BATF expression in the human A549 NSCLC cell line and assessed by reverse transcription-quantitative PCR and western blotting. Cell proliferation was evaluated by MTT assay and Celigo imaging cytometry. Apoptosis was detected by fluorescence-activated cell sorting and caspase 3/7 activity analysis. The results revealed that knockdown of BATF inhibited the proliferation of A549 cells. Compared with that of the control group, the apoptosis rate of the BATF-shRNA group was significantly higher. In summary, knockdown of BATF inhibited the proliferation of A549 cells and promoted apoptosis. These results provide important information about the underlying mechanism of the pathogenesis of NSCLC.

The Prognostic Values Of Circulating Tumor Cells In Lung Carcinoma: An Analysis On 98 Chinese Patients

Aim

To examine the prognostic values of circulating tumor cells (CTCs) in patients with advanced lung cancer.

Patients and methods

A total of 98 patients with their CTCs enumerated in 2017 was recruited. Data were retrieved from medical records for comparison. Patients’ overall survival (OS) and progression-free survival (PFS) were studied using Kaplan-Meier curve with log rank test.

Results

Seventy-three percent of the patients were male, and nearly half of the patients (44.8%) were smokers. Most tumors were adenocarcinoma (73.4%), and about 60% of the cases were diagnosed at stage IV. Half of the patients showing less than nine CTCs. Patients’ OS were significantly associated with total CTC count (P=0.047), epithelial CTC count (P=0.027), mixed CTC count (P=0.004), and use of adjuvant chemotherapy (P=0.001). For PFS, it was strongly associated with tumor backgrounds (T stage, P=0.002; M stage, P=0.001; TMN stage, P<0.001), cancer biomarkers (CEA, P=0.004; CA125, P=0.004; CA153, P=0.045), and treatment strategy (surgical intervention, P=0.025; first-line chemotherapy, P<0.001).

Conclusion

The present study clearly indicated the significant associations between CTC and overall survival of patients with lung cancer.

KIAA1211 plays an oncogenic role in human non-small cell lung cancer

One of the main causes of cancer disease and death worldwide is lung cancer. Our study focused on the function of KIAA1211 in non-small cell lung cancer (NSCLC). According to the data about NSCLC patients that from the Cancer Genome Atlas (TCGA), we found that KIAA1211 in NSCLC (P=5.06E-06) was significantly higher than the adjacent normal. Lentivirus-mediated short hairpin RNA (shRNA) was used to knockdown BATF expression in the human A549 NSCLC cell line and assessed by RT-qPCR and Western blot. Cell proliferation was evaluated by MTT assay and Celigo imaging cytometry. Cell apoptosis were detected by Annexin V staining. The test results showed that KIAA1211-shRNA A549 and SPC-A-1 cells can inhibit cell proliferation, and the apoptosis rate of KIAA1211-shRNA group was significantly higher than that of the control group. Knockdown of KIAA1211 inhibited NSCLC progression in xenograft tumor model. In conclusion, KIAA1211 could regulate NSCLC cells proliferation and apoptosis in vitro and in vivo. KIAA1211 may serve as a potent target for the treatment of NSCLC.

Cross-disease analysis identified novel common genes for both lung adenocarcinoma and lung squamous cell carcinoma

Lung squamous cell carcinoma (LSCC) exhibits a number of similarities with lung adenocarcinoma (LA) in terms of copy number alterations. However, compared with LA, the range of genetic alterations in LSCC is less understood. In the present study, a large-scale literature-based search of LA-associated genes and LSCC-associated genes was performed to identify the genetic basis in common with these two diseases. For each of the LA-associated genes, a mega-analysis was performed to test its expression variations in LSCC using 11 RNA expression datasets, with significant genes identified using statistical analysis. Subsequently, a functional pathway analysis was performed to identify a possible association between any of the significant genes identified from the mega-analysis and LSCC, followed by a co-expression analysis. A multiple linear regression (MLR) model was employed to investigate the possible influence of sample size, country of origin and study date on gene expression in patients with LSCC. Disease-gene association data analysis identified 1,178 genes involved in LA, 334 in LSCC, with a significant overlap of 187 genes (P<1.02×⁻¹⁶¹). Mega-analysis revealed that three LA-associated genes, such as solute carrier family 2 member 1 (SLC2A1), endothelial PAS domain protein 1 (EPAS1) and cyclin-dependent kinase 4 (CDK4), were significantly associated with LSCC (P<1.60×10⁻⁸), with multiple potential pathways identified by functional pathway analysis, which were further validated by co-expression analysis. The present MLR analysis suggested that the country of origin was a significant factor for the levels of expression of all three genes in patients with LSCC (P<4.0×10⁻³). Collectively, the present results suggested that genes associated with LA should be further investigated for their association with LSCC. In addition, SLC2A1, EPAS1 and CDK4 may be novel risk genes associated with LA and LSCC.

Role of KRAS in regulating normal human airway basal cell differentiation

BACKGROUND

KRAS is a GTPase that activates pathways involved in cell growth, differentiation and survival. In normal cells, KRAS-activity is tightly controlled, but with specific mutations, the KRAS protein is persistently activated, giving cells a growth advantage resulting in cancer. While a great deal of attention has been focused on the role of mutated KRAS as a common driver mutation for lung adenocarcinoma, little is known about the role of KRAS in regulating normal human airway differentiation.

METHODS

To assess the role of KRAS signaling in regulating differentiation of the human airway epithelium, primary human airway basal stem/progenitor cells (BC) from nonsmokers were cultured on air-liquid interface (ALI) cultures to mimic the airway epithelium in vitro. Modulation of KRAS signaling was achieved using siRNA-mediated knockdown of KRAS or lentivirus-mediated over-expression of wild-type KRAS or the constitutively active G12 V mutant. The impact on differentiation was quantified using TaqMan quantitative PCR, immunofluorescent and immunohistochemical staining analysis for cell type specific markers. Finally, the impact of cigarette smoke exposure on KRAS and RAS protein family activity in the airway epithelium was assessed in vitro and in vivo.

RESULTS

siRNA-mediated knockdown of KRAS decreased differentiation of BC into secretory and ciliated cells with a corresponding shift toward squamous cell differentiation. Conversely, activation of KRAS signaling via lentivirus mediated over-expression of the constitutively active G12 V KRAS mutant had the opposite effect, resulting in increased secretory and ciliated cell differentiation and decreased squamous cell differentiation. Exposure of BC to cigarette smoke extract increased KRAS and RAS protein family activation in vitro. Consistent with these observations, airway epithelium brushed from healthy smokers had elevated RAS activation compared to nonsmokers.

CONCLUSIONS

Together, these data suggest that KRAS-dependent signaling plays an important role in regulating the balance of secretory, ciliated and squamous cell differentiation of the human airway epithelium and that cigarette smoking-induced airway epithelial remodeling is mediated in part by abnormal activation of KRAS-dependent signaling mechanisms.