Polyamine-mediated ferroptosis amplification acts as a targetable vulnerability in cancer.

Targeting ferroptosis, an iron-dependent form of regulated cell death triggered by the lethal overload of lipid peroxides, in cancer therapy is impeded by our limited understanding of the intersection of tumour's metabolic feature and ferroptosis vulnerability. In the present study, arginine is identified as a ferroptotic promoter using a metabolites library. This effect is mainly achieved through arginine's conversion to polyamines, which exerts their potent ferroptosis-promoting property in an H2O2-dependent manner. Notably, the expression of ornithine decarboxylase 1 (ODC1), the critical enzyme catalysing polyamine synthesis, is significantly activated by the ferroptosis signal--iron overload--through WNT/MYC signalling, as well as the subsequent elevated polyamine synthesis, thus forming a ferroptosis-iron overload-WNT/MYC-ODC1-polyamine-H2O2 positive feedback loop that amplifies ferroptosis. Meanwhile, we notice that ferroptotic cells release enhanced polyamine-containing extracellular vesicles into the microenvironment, thereby further sensitizing neighbouring cells to ferroptosis and accelerating the "spread" of ferroptosis in the tumour region. Besides, polyamine supplementation also sensitizes cancer cells or xenograft tumours to radiotherapy or chemotherapy through inducing ferroptosis. Considering that cancer cells are often characterized by elevated intracellular polyamine pools, our results indicate that polyamine metabolism exposes a targetable vulnerability to ferroptosis and represents an exciting opportunity for therapeutic strategies for cancer.

Transcription factor ZNF263 enhances EGFR-targeted therapeutic response and reduces residual disease in lung adenocarcinoma.

EGF receptor (EGFR) tyrosine kinase inhibitors (TKIs) have achieved clinical success in lung adenocarcinoma (LUAD). However, tumors often show profound but transient initial response and then gain resistance. We identify transcription factor ZNF263 as being significantly decreased in osimertinib-resistant or drug-tolerant persister LUAD cells and clinical residual tumors. ZNF263 overexpression improves the initial response of cells and delays the formation of persister cells with osimertinib treatment. We further show that ZNF263 binds and recruits DNMT1 to the EGFR gene promoter, suppressing EGFR transcription with DNA hypermethylation. ZNF263 interacts with nuclear EGFR, impairing the EGFR-STAT5 interaction to enhance AURKA expression. Overexpressing ZNF263 also makes tumor cells with wild-type EGFR expression or refractory EGFR mutations more susceptible to EGFR inhibition. More importantly, lentivirus or adeno-associated virus (AAV)-mediated ZNF263 overexpression synergistically suppresses tumor growth and regrowth with osimertinib treatment in xenograft animal models. These findings suggest that enhancing ZNF263 may achieve complete response in LUAD with EGFR-targeted therapies.

IL6-STAT3-C/EBPß-IL6 positive feedback loop in tumor-associated macrophages promotes the EMT and metastasis of lung adenocarcinoma.

BACKGROUND: Lung cancer is one of the most common tumors in the world, and metastasis is one of the major causes of tumor-related death in lung cancer patients. Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment (TME) and are frequently associated with tumor metastasis in human cancers. However, the regulatory mechanisms of TAMs in lung cancer metastasis remain unclear. METHODS: Single-cell sequencing analysis of lung cancer and normal tissues from public databases and from 14 patients who underwent surgery at Zhongshan Hospital was performed. In vitro co-culture experiments were performed to evaluate the effects of TAMs on lung cancer migration and invasion. Changes in the expression of IL-6, STAT3, C/EBPΒ, and EMT pathway were verified using RT-qPCR, western blotting, and immunofluorescence. Dual luciferase reporter assays and ChIP were used to reveal potential regulatory sites on the transcription factor sets. In addition, the effects of TAMs on lung cancer progression and metastasis were confirmed by in vivo models. RESULTS: TAM infiltration is associated with tumor progression and poor prognosis. IL-6 secreted by TAMs can activate the JAK2/STAT3 pathway through autocrine secretion, and STAT3 acts as a transcription factor to activate the expression of C/EBPß, which further promotes the transcription and expression of IL-6, forming positive feedback loops for IL6-STAT3-C/EBPß-IL6 in TAMs. IL-6 secreted by TAMs promotes lung cancer progression and metastasis in vivo and in vitro by activating the EMT pathway, which can be attenuated by the use of JAK2/STAT3 pathway inhibitors or IL-6 monoclonal antibodies. CONCLUSIONS: Our data suggest that TAMs promote IL-6 expression by forming an IL6-STAT3-C/EBPß-IL6 positive feedback loop. Released IL-6 can induce the EMT pathway in lung cancer to enhance migration, invasion, and metastasis. The use of IL-6-neutralizing antibody can partially counteract the promotion of LUAD by TAMs. A novel mechanism of macrophage-promoted tumor progression was revealed, and the IL6-STAT3-C/EBPß-IL6 signaling cascade may be a potential therapeutic target against lung cancer.

MAFF confers vulnerability to cisplatin-based and ionizing radiation treatments by modulating ferroptosis and cell cycle progression in lung adenocarcinoma.

AIMS: Lung cancer is the leading cause of cancer mortality and lung adenocarcinoma (LUAD) accounts for more than half of all lung cancer cases. Tumor elimination is mostly hindered by drug resistance and the mechanisms remain to be explored in LUAD. METHODS: CRISPR screens in cell and murine models and single-cell RNA sequencing were conducted, which identified MAF bZIP transcription factor F (MAFF) as a critical factor regulating tumor growth and treatment resistance in LUAD. RNA and ChIP sequencing analyses were performed for transcriptional target expression and specific binding sites of MAFF. Functions of MAFF in inhibiting tumor growth and promoting cisplatin or irradiation efficacy were investigated using cellular and xenograft models. RESULTS: Patients with lung adenocarcinoma and reduced MAFF expression had worse clinical outcomes. MAFF inhibited tumor cell proliferation by regulating the expression of SLC7A11, CDK6, and CDKN2C, promoting ferroptosis and preventing cell cycle progression from G1 to S. MAFF also conferred tumor cells vulnerable to cisplatin-based or ionizing radiation treatments. MAFF reduction was a final event in the acquisition of cisplatin resistance of LUAD cells. The intracellular cAMP/PKA/CREB1 pathway upregulated MAFF in response to cisplatin-based or ionizing radiation treatments. CONCLUSIONS: MAFF suppresses tumor growth, and pharmacological agonists targeting MAFF may improve cisplatin or irradiation therapies for lung adenocarcinoma patients.

Targeting TAM-secreted S100A9 effectively enhances the tumor-suppressive effect of metformin in treating lung adenocarcinoma.

Metformin's effect on tumor treatment was complex, because it significantly reduced cancer cell proliferation in vitro, but made no difference in prognosis in several clinical cohorts. Our transcriptome sequencing results revealed that tumor-associated macrophage (TAM) infiltration significantly increased in active lung adenocarcinoma (LUAD) patients with long-term metformin use. We further identified that the tumor suppressive effect of metformin was more significant in mice after the depletion of macrophages, suggesting that TAMs might play an important role in metformin's effects in LUAD. Combining 10X Genomics single-cell sequencing of tumor samples, transcriptome sequencing of metformin-treated TAMs, and the ChIP-Seq data of the Encode database, we identified and validated that metformin significantly increased the expression and secretion of S100A9 of TAMs through AMPK-CEBP/ß pathway. For the downstream, S100A9 binds to RAGE receptors on the surface of LUAD cells, and then activates the NF-κB pathway to promote EMT and progression of LUAD, counteracting the inhibitory effect of metformin on LUAD cells. In cell-derived xenograft models (CDX) and patient-derived xenograft models (PDX) models, our results showed that neutralizing antibodies targeting TAM-secreted S100A9 effectively enhanced the tumor suppressive effect of metformin in treating LUAD. Our results will enable us to better comprehend the complex role of metformin in LUAD, and advance its clinical application in cancer treatment.

Identification of the relationship between single-cell N6-methyladenosine regulators and the infiltrating immune cells in esophageal carcinoma.

Background: N6-methyladenosine (m6A) RNA methylation plays a crucial role in important genomic processes in a variety of malignancies. However, the characterization of m6A with infiltrating immune cells in the tumor microenvironment (TME) in esophageal squamous carcinoma (ESCC) remains unknown. Methods: The single-cell transcriptome data from five ESCC patients in our hospital were analyzed, and TME clusters associated with prognosis and immune checkpoint genes were investigated. Cell isolation and qPCR were conducted to validate the gene characterization in different cells. Results: According to distinct biological processes and marker genes, macrophages, T cells, and B cells clustered into three to four different subgroups. In addition, we demonstrated that m6A RNA methylation regulators were strongly related to the clinical and biological features of ESCC. Analysis of transcriptome data revealed that m6A-mediated TME cell subsets had high predictive value and showed a close relationship with immune checkpoint genes. The validation results from qPCR demonstrated the characteristics of essential genes. CellChat analysis revealed that RNA from TME cells m6A methylation-associated cell subtypes had substantial and diversified interactions with cancer cells. Further investigation revealed that MIF- (CD74+CXCR4) and MIF- (CD74+CD44) ligand-receptor pairings facilitated communication between m6A-associated subtypes of TME cells and cancer cells. Conclusion: Overall, our study demonstrated for the first time the function of m6A methylation-mediated intercellular communication in the microenvironment of tumors in controlling tumor development and anti-tumor immune regulation in ESCC.

The genomic signature of resistance to platinum-containing neoadjuvant therapy based on single-cell data.

BACKGROUND: Neoadjuvant chemotherapy (NACT) becomes the first-line option for advanced tumors, while patients who are not sensitive to it may not benefit. Therefore, it is important to screen patients suitable for NACT. METHODS: Single-cell data of lung adenocarcinoma (LUAD) and esophageal squamous carcinoma (ESCC) before and after cisplatin-containing (CDDP) NACT and cisplatin IC50 data of tumor cell lines were analyzed to establish a CDDP neoadjuvant chemotherapy score (NCS). Differential analysis, GO, KEGG, GSVA and logistic regression models were performed by R. Survival analysis were applied to public databases. siRNA knockdown in A549, PC9, TE1 cell lines, qRT-PCR, western-blot, cck8 and EdU experiments were used for further verification in vitro. RESULTS: 485 genes were expressed differentially in tumor cells before and after neoadjuvant treatment for LUAD and ESCC. After combining the CDDP-associated genes, 12 genes, CAV2, PHLDA1, DUSP23, VDAC3, DSG2, SPINT2, SPATS2L, IGFBP3, CD9, ALCAM, PRSS23, PERP, were obtained and formed the NCS score. The higher the score, the more sensitive the patients were to CDDP-NACT. The NCS divided LUAD and ESCC into two groups. Based on differentially expressed genes, a model was constructed to predict the high and low NCS. CAV2, PHLDA1, ALCAM, CD9, IGBP3 and VDAC3 were significantly associated with prognosis. Finally, we demonstrated that the knockdown of CAV2, PHLDA1 and VDAC3 in A549, PC9 and TE1 significantly increased the sensitivity to cisplatin. CONCLUSIONS: NCS scores and related predictive models for CDDP-NACT were developed and validated to assist in selecting patients who might benefit from it.

Retinol Saturase Mediates Retinoid Metabolism to Impair a Ferroptosis Defense System in Cancer Cells.

Ferroptosis is an iron-dependent form of regulated cell death induced by the lethal overload of lipid peroxides in cellular membranes. In recent years, modulating ferroptosis has gained attention as a potential therapeutic approach for tumor suppression. In the current study, retinol saturase (RETSAT) was identified as a significant ferroptosis mediator using a publicly accessible CRISPR/Cas9 screening dataset. RETSAT depletion protected tumor cells from lipid peroxidation and subsequent cell death triggered by various ferroptosis inducers. Furthermore, exogenous supplementation with retinoids, including retinol (the substrate of RETSAT) and its derivatives retinal and retinoic acid, also suppressed ferroptosis, whereas the product of RETSAT, 13, 14-dihydroretinol, failed to do so. As effective radical-trapping antioxidant, retinoids protected the lipid membrane from autoxidation and subsequent fragmentation, thus terminating the cascade of ferroptosis. Pseudotargeted lipidomic analysis identified an association between retinoid regulation of ferroptosis and lipid metabolism. Retinoic acid, but not 13, 14-dihydroretinoic acid, interacted with its nuclear receptor and activated transcription of stearoyl-CoA desaturase, which introduces the first double bond into saturated fatty acid and thus catalyzes the generation of monounsaturated fatty acid, a known ferroptosis suppressor. Therefore, RETSAT promotes ferroptosis by transforming retinol to 13, 14-dihydroretinol, thereby turning a strong anti-ferroptosis regulator into a relatively weak one. SIGNIFICANCE: Retinoids have ferroptosis-protective properties and can be metabolized by RETSAT to promote ferroptosis, suggesting the possibility of targeting retinoid metabolism in cancer as a treatment strategy to trigger ferroptosis.

Lobe-Specific Lymph Node Dissection May be Feasible for Clinical N0 Solid-Predominant Part-Solid Lung Adenocarcinoma With Solid Component Diameter ≤ 2 cm.

BACKGROUND: Lymph node (LN) involvement was not rare in patients with radiological solid-predominant part-solid nodules (PSNs). The lymph node dissection (LND) strategy remained unclear. MATERIALS AND METHODS: Six hundred seventy-two patients with clinical N0 solid-predominant PSNs (0.5 < consolidation-to-tumor ratio < 1) receiving systematic LND (development cohort, n = 598) or limited LND (validation cohort A, n = 74) at 2 Chinese institutions from 2008 to 2016 were collected. The development cohort was utilized to investigate the incidence and pattern of LN metastasis. Lobe-specific LN metastasis pattern was defined as superior mediastinal LN involvement from upper-lobe tumor or inferior mediastinal LN involvement from lower-lobe tumor. To further validate the LN metastasis pattern observed in the development cohort, validation cohort B consisting of 7273 patients with primary lung adenocarcinomas who received surgery from 2016 to 2021 was identified. The clinical outcomes between the development cohort and validation cohort A were compared in order to assess the feasibility of limited LND. RESULTS: LN involvement rate for solid-predominant PSNs was 10.0%. Larger solid component diameter (P = .005) was independently associated with increased risk of LN involvement. In upper/lower lobes solid-predominant PSNs with solid component diameter ≤ 2 cm, a lobe-specific LN involvement pattern was identified. Further validation indicated that the observed mediastinal LN involvement pattern was generalizable, and the oncologic outcomes did not vary by the extent of LND in solid-predominant PSNs with solid component diameter ≤ 2 cm. CONCLUSION: Lobe-specific LND might be feasible for solid-predominant PSNs with solid component diameter ≤ 2 cm. For other solid-predominant PSNs, systematic LND should be recommended.

Dissecting the single-cell transcriptome network of macrophage and identifies a signature to predict prognosis in lung adenocarcinoma.

PURPOSE: The tumor immune microenvironment (TME) plays a vital role in tumorigenesis, progression, and treatment. Macrophages, as an important component of the tumor microenvironment, play an essential role in antitumor immunity and TME remodeling. In this study, we aimed to explore the different functions of different origins macrophages in TME and their value as potential predictive markers of prognosis and treatment. METHODS: We performed single-cell analysis using 21 lung adenocarcinoma (LUAD), 12 normal, and four peripheral blood samples from our data and public databases. A prognostic prediction model was then constructed using 502 TCGA patients and explored the potential factors affecting prognosis. The model was validated using data from 4 different GEO datasets with 544 patients after integration. RESULTS: According to the source of macrophages, we classified macrophages into alveolar macrophages (AMs) and interstitial macrophages (IMs). AMs mainly infiltrated in normal lung tissue and expressed proliferative, antigen-presenting, scavenger receptors genes, while IMs occupied the majority in TME and expressed anti-inflammatory, lipid metabolism-related genes. Trajectory analysis revealed that AMs rely on self-renew, whereas IMs originated from monocytes in the blood. Cell-to-cell communication showed that AMs interacted mainly with T cells through the MHC I/II signaling pathway, while IMs mostly interacted with tumor-associated fibrocytes and tumor cells. We then constructed a risk model based on macrophage infiltration and showed an excellent predictive power. We further revealed the possible reasons for its potential prognosis prediction by differential genes, immune cell infiltration, and mutational differences. CONCLUSION: In conclusion, we investigated the composition, expression differences, and phenotypic changes of macrophages from different origins in lung adenocarcinoma. In addition, we developed a prognostic prediction model based on different macrophage subtype infiltration, which can be used as a valid prognostic biomarker. New insights were provided into the role of macrophages in the prognosis and potential treatment of LUAD patients.

HNF4G increases cisplatin resistance in lung adenocarcinoma via the MAPK6/Akt pathway.

Background: Lung adenocarcinoma is one of the most common tumors, and cisplatin is frequently used in treating lung adenocarcinoma patients. This study aimed to look into the roles and mechanisms of HNF4G in cisplatin resistance of lung adenocarcinoma. Materials & Methods: Cisplatin resistance and gene expression data of 542 cell lines from the CTRP and CCLE databases were analyzed. HNF4G expression was detected in the lung adenocarcinoma cell lines after treatment with various concentrations of cisplatin. Cisplatin sensitivity curves were detected in cells that overexpressed or knocked down HNF4G. The ChIP-Seq data were then analyzed to identify the targets of HNF4G involved in cisplatin resistance. Expression and phosphorylation of the MAPK6/Akt pathway were detected after HNF4G was overexpressed or knocked down. Finally, ChIP-qPCR and dual-luciferase assays were used to investigate the regulation of HNF4G on MAPK6. Results: In cell lines, high expression of HNF4G was significantly positively correlated with cisplatin resistance, and lung adenocarcinoma patients who had high HNF4G expression had a poor prognosis. Cisplatin treatment increased HNF4G expression, and overexpression of HNF4G significantly increased the resistance to cisplatin in A549 and HCC827 cells, whereas knockdown of HNF4G had the opposite effect. HNF4G overexpression increased MAPK6 expression and activated the MAPK6/Akt pathway, while an Akt inhibitor reduced the effects of HNF4G on cisplatin resistance. HNF4G bound to the MAPK6 promoter region, promoting MAPK6 expression, according to ChIP-qPCR and luciferase assays. Conclusion: By binding to the MAPK6 promoter region, HNF4G promotes MAPK6 expression and subsequent Akt phosphorylation, resulting in resistance to cisplatin in lung adenocarcinoma.

The comparison of Lobe-Specific or Systematic Mediastinal Lymph Node Dissection for Early-Stage Lung Adenocarcinoma With Consolidation Tumor Ratio Over 0.5.

INTRODUCTION: Surgery is the most effective treatment for early-stage lung cancer. This study will propose a personalized plan for mediastinal lymph node dissection in early-stage lung adenocarcinoma to reduce the risk of surgery and improve the quality of life. METHODS: This study retrospectively analyzed the patients underwent lobectomy and lymph node dissection in the Department of Thoracic Surgery, Zhongshan Hospital, Fudan University. Clinical stage I lung adenocarcinoma patients with solid component ratio (CTR) between 0.5 and 1 were included. Patients were divided into systematic (S-MLND) and lobe-specific (L-MLND) mediastinal lymph node dissection groups. The days of hospitalization, the presence or absence of complications, the recurrence-free survival rate, and the overall survival rate were calculated to evaluate the postoperative quality and operation risk of the patients. RESULTS: 210 patients (138 L-MLND and 72 S-MLND) were included. 2 lymph node metastases appeared in the S-MLND group while none in the L-MLND group (P = .049). No differences were shown in age, tumor site, size, solid component, degree of tumor invasion, and stage. The proportion of patients with severe postoperative cough and the length of hospital stay in the L-MLND group decreased. The 5-year OS of the entire cohort was 98.1%, 98.6% in L-MLND, compared with 97.2% in S-MLND; RFS was 94.8%, 95.7% in L-MLND, compared with 93.0% in S-MLND. CONCLUSION: For cIA lung adenocarcinoma, according to the Thin-slice CT within 1 month before the operation, if the main lesion was less than 3 cm and CTR over 0.5, L-MLND is as effective as S-MLND.

Identification and validation of the mitochondrial function related hub genes by unsupervised machine learning and multi-omics analyses in lung adenocarcinoma.

Background: The mitochondrion and its associated genes were heavily implicated in developing and therapy tumors as the primary cellular organelle in charge of metabolic reprogramming and ferroptosis. Our work focuses on discovering new potential targets while analyzing the multi-omics data of mitochondria-related genes in lung adenocarcinoma (LUAD). Methods: The Cancer Genome Atlas (TCGA) database provided multi-omics data for LUAD patients. Based on the expression profile of the genes associated with mitochondria, the patients were grouped by the unsupervised clustering method. R was used to explore the differential expressed protein-code gene, miRNA, and lncRNA, as well as their enriched functions and ceRNA networks. Additionally, the discrepancy between immune infiltration and genetic variation was comprehensively characterized. Our clinical samples and in vitro experiments investigated the hub gene determined by LASSO and batch analysis. Results: Two clusters are distinguished using unsupervised consensus clustering based on mitochondrial heterogeneity. The integrated analysis emphasized that patients in cluster B had a worse prognosis, higher mutation frequencies, and less immune cell infiltration. The hub genes DARS2 and COX5B are identified by further analysis using LASSO penalization. In vitro experiments indicated that DARS2 and COX5B knockdown inhibited tumor cell proliferation. The specimen of our hospital cohort conducted the immunohistochemistry analysis and validated that DARS2 and COX5B's expression was significantly higher in the tumor than in adjacent normal tissue and correlated to LUAD patients' prognosis. Conclusion: Our observations implied that LUAD patients' tumors had distinct mitochondrial function heterogeneity with different clinical and molecular characteristics. DARS2 and COX5B might be critical genes involved in mitochondrial alterations and potential therapeutic targets.

FSCN1 induced PTPRF-dependent tumor microenvironment inflammatory reprogramming promotes lung adenocarcinoma progression via regulating macrophagic glycolysis.

PURPOSE: Macrophages (MΦs) play a dual role in the promotion and suppression of lung adenocarcinoma (LUAD), the function of which is influenced by the metabolic status. The role of protein tyrosine phosphatase receptor type F (PTPRF) in cancer has not been elucidated, and its role in MΦs remains to be seen. METHODS: The Seahorse XFe 96 Cell Flow Analyzer detected glucose metabolism in tumor cells and macrophages. The expressions of FSCN1, M-CSF, IL4, PTPRF and IGF1 in macrophages were detected by Western blotting and qRT-PCR. Binding of FSCN1 and IGF1R was detected by co-immunoprecipitation. The tumor status in animals was observed using the IVIS Lumina III imaging system. RESULTS: We found that Fascin Actin-Bundling Protein 1 (FSCN1) activates the PI3K-AKT and JAK-STAT signaling pathways in LUAD cells via binding to IGF-1R, thereby promoting the secretion of cytokines such as IL4 and M-CSF. IL4 and M-CSF promote the expression of PTPRF in MΦs, leading to M2 polarization of MΦs by increasing glucose intake and lactate production. In return, M2-type MΦs act on LUAD cells by secreting cytokines such as IGF-1, CCL2, and IL10, which ultimately promote tumor progression. In vivo experiments proved that the knockdown of FSCN1 in A549 cells and PTPRF in MΦs greatly reduced LUAD proliferative and metastatic capacity, which was consistent with the in vitro findings. CONCLUSIONS: This study investigated the reprogramming effects of FSCN1 and PTPRF on inflammatory cytokines in the LUAD microenvironment, revealing potential mechanisms by which FSCN1 and PTPRF promote tumor progression and providing a new experimental basis for LUAD treatment.

Weighted Correlation Network Analysis of Cancer Stem Cell-Related Prognostic Biomarkers in Esophageal Squamous Cell Carcinoma.

Background: The role of cancer stem cells in esophageal squamous cell carcinoma (ESCC) remains unclear. Methods: The mRNA stemness index (mRNAsi) of 179 ESCC patients (GSE53625) was calculated using a machine learning algorithm based on their mRNA expression. Stemness-related genes were identified by weighted correlation network analysis (WGCNA) and LASSO regression, whose associations with mutation status, immune cell infiltrations, and potential compounds were also analyzed. The role of these genes in proliferation and their expressions was assessed in ESCC cell lines and 112 samples from our center. Results: The ESCC samples had significantly higher mRNAsi than the normal tissues. Patients with high mRNAsi exhibited higher worse OS. Seven stemness-related genes were identified by WGCNA and LASSO regression, based on which a risk-predicted score model was constructed. Among them, CST1, CILP, PITX2, F2RL2, and RIOX1 were favorable for OS, which were adverse for DPP4 and ZFHX4 in the GSE53625 dataset. However, RIOX1 was unfavorable for OS in patients from our center. In vitro assays showed that CST1, CILP, PITX2, F2RL2, and RIOX1 were pro-proliferated, which were opposite for DDP4 and ZFHX4. In addition, SMARCA4, NOTCH3, DNAH5, and KALRN were more mutated in the low-score group. The low-score group had significantly more memory B cells, monocytes, activated NK cells, and Tregs and less macrophages M2, resting mast cells, and resting dendritic cells. Conclusions: Seven stemness-related genes are significantly related to the prognosis, gene mutations, and immune cell infiltration of ESCC. Some potential anticancer compounds may be favorable for OS.

miR-6077 promotes cisplatin/pemetrexed resistance in lung adenocarcinoma via CDKN1A/cell cycle arrest and KEAP1/ferroptosis pathways.

Lung adenocarcinoma (LUAD) is one of the most common malignancies worldwide. Combination chemotherapy with cisplatin (CDDP) plus pemetrexed (PEM) remains the predominant therapeutic regimen; however, chemoresistance greatly limits its curative potential. Here, through CRISPR-Cas9 screening, we identified miR-6077 as a key driver of CDDP/PEM resistance in LUAD. Functional experiments verified that ectopic overexpression of miR-6077 desensitized LUAD cells to CDDP/PEM in both cell lines and patient-derived xenograft models. Through RNA sequencing in cells and single-cell sequencing of samples from patients with CDDP/PEM treatments, we observed CDDP/PEM-induced upregulation of CDKN1A and KEAP1, which in turn activated cell-cycle arrest and ferroptosis, respectively, thus leading to cell death. Through miRNA pull-down, we identified and validated that miR-6077 targets CDKN1A and KEAP1. Furthermore, we demonstrated that miR-6077 protects LUAD cells from cell death induced by CDDP/PEM via CDKN1A-CDK1-mediated cell-cycle arrest and KEAP1-NRF2-SLC7A11/NQO1-mediated ferroptosis, thus resulting in chemoresistance in multiple LUAD cells both in vitro and in vivo. Moreover, we found that GMDS-AS1 and LINC01128 sensitized LUAD cells to CDDP/PEM by sponging miR-6077. Collectively, these results imply the critical role of miR-6077 in LUAD's sensitivity to CDDP/PEM, thus providing a novel therapeutic strategy for overcoming chemoresistance in clinical practice.

Multi-omics analysis identifies distinct subtypes with clinical relevance in lung adenocarcinoma harboring KEAP1/NFE2L2.

Backgrounds: Lung adenocarcinoma is one of the most common malignant tumors, in which KEAP1-NFE2L2 pathway is altered frequently. The biological features and intrinsic heterogeneities of KEAP1/NFE2L2-mutant lung adenocarcinoma remain unclear. Methods: Multiplatform data from The Cancer Genome Atlas (TCGA) were acquired to identify two subtypes of lung adenocarcinoma harboring KEAP1/NFE2L2 mutations. Bioinformatic analyses, including immune microenvironment, methylation level and mutational signature, were performed to characterize the intrinsic heterogeneities. Meanwhile, initial results were validated by using in silico assessment of common lung adenocarcinoma cell lines, which revealed consistent features of mutant subtypes. Furthermore, drug sensitivity screening was conducted based on public datasets. Results: Two mutant subtypes (P1 and P2) of 89 patients were identified in TCGA. P2 patients had significantly higher levels of smoking and worse survival compared with P1 patients. The P2 subset was characterized by active immune microenvironment and more smoking-induced genomic alterations with respect to methylation and somatic mutations. Validations of the corresponding features in 20 mutant cell lines were achieved. Several compounds which were sensitive to mutant subtypes of lung adenocarcinoma were identified, such as inhibitors of PI3K/Akt and IGF1R signaling pathways. Conclusions: KEAP1/NFE2L2-mutant lung adenocarcinoma showed potential heterogeneities. The intrinsic heterogeneities of KEAP1/NFE2L2 were associated with immune microenvironment and smoking-related genomic aberrations.