Prognostic roles of dysregulated METTL3 protein expression in cancers and potential anticancer value by inhibiting METTL3 function.

BACKGROUND: Many studies have demonstrated the relationship between METTL3 protein expression and clinical outcomes in various cancers and elucidated the mechanism by which METTL3 disrupts the behavior of cancer cells. Here, we attempted to define the prognostic value of METTL3 protein in patients with cancer via systematic analysis and explored the potential effect of inhibiting METTL3 using its specific inhibitor. METHODS: We searched PubMed, Embase, and the Web of Science databases for studies that elucidated the prognostic value of METTL3 protein expression in all cancer types and then calculated the pooled hazard ratios with 95% confidence intervals for the overall survival (OS) of all cancer types and subgroups. Data from The Cancer Genome Atlas dataset were used to study METTL3 mRNA expression in cancers. Further, the effects of a METTL3-specific inhibitor were studied in cancer cells via the colony formation assay, the cell proliferation assay, and apoptosis detection. RESULTS: Meta-analysis of the 33 cohorts in 32 studies (3666 patients in total) revealed that higher METTL3 protein expression indicated poor OS in the majority of cancers. Bioinformatics analysis of METTL3 mRNA expression and cancer prognosis did not show the extremely prominent prognostic value of METTL3 mRNA. Nevertheless, the METTL3-specific inhibitor attenuated cell proliferation and cell cloning formation and promoted apoptosis. CONCLUSIONS: METTL3 protein expression is associated with poor prognosis in most cancer types and could be a biomarker for OS. Further, METTL3 inhibition might be a potential treatment strategy for cancers.

A dual-enzyme-like photosensitive nanozyme for remodeling the tumor immunosuppressive microenvironment to enhance immunotherapy.

In "immune-cold" tumors, the upregulation of immunosuppressive cells and insufficient infiltration of lymphocytes contribute to the resistance against immune therapy. Herein, we have developed a dual-enzyme-like photosensitive nanozyme (PBAF) to remodel the tumor immunosuppressive microenvironment (TIME) and induce the tumor infiltration of cytotoxic T lymphocytes (CTLs). Specifically, PBAF exhibits peroxidase (POD)-like activity and glutathione oxidase (GSHOx)-like activity and can be stimulated by 750 nm laser, promoting oxidative stress at the tumor site. Consequently, this process further leads to the reconstruction of TIME in animal experiments, inducing tumor-associated macrophages (TAMs) toward the immunostimulatory M1 phenotype, eliminating myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs). Simultaneously, PBAF also promotes dendritic cells (DCs) maturation to enhance CTLs infiltration into the tumor. The remodeled TIME and enhanced immune responses by PBAF demonstrate significant post-administration inhibition of recurrence and metastasis in the treatment of malignant tumors.

Diagnostic Value of GDF10 for the Tumorigenesis and Immune Infiltration in Lung Squamous Cell Carcinoma.

OBJECTIVE: Lung squamous cell carcinoma (LUSC) is associated with a low survival rate. Evidence suggests that bone morphogenetic proteins (BMPs) and their receptors (BMPRs) play crucial roles in tumorigenesis and progression. However, a comprehensive analysis of their role in LUSC is lacking. Our study aimed to explore the relationship between BMPs/BMPRs expression levels and the tumorigenesis and prognosis of LUSC. METHODS: The "R/Limma" package was utilized to analyze the differential expression characteristics of BMPs/BMPRs in LUSC, using data from TCGA, GTEx, and GEO databases. Concurrently, the "survminer" packages were employed to investigate their prognostic value and correlation with clinical features in LUSC. The core gene associated with LUSC progression was further explored through weighted gene correlation network analysis (WGCNA). LASSO analysis was conducted to construct a prognostic risk model for LUSC. Clinical specimens were examined by immunohistochemical analysis to confirm the diagnostic value in LUSC. Furthermore, based on the tumor immune estimation resource database and tumor-immune system interaction database, the role of the core gene in the tumor microenvironment of LUSC was explored. RESULTS: GDF10 had a significant correlation only with the pathological T stage of LUSC, and the protein expression level of GDF10 decreased with the tumorigenesis of LUSC. A prognostic risk model was constructed with GDF10 as the core gene and 5 hub genes (HRASLS, HIST1H2BH, FLRT3, CHEK2, and ALPL) for LUSC. GDF10 showed a significant positive correlation with immune cell infiltration and immune checkpoint expression. CONCLUSION: GDF10 might serve as a diagnostic biomarker reflecting the tumorigenesis of LUSC and regulating the tumor immune microenvironment to guide more effective treatment for LUSC.

METTL3 drives NSCLC metastasis by enhancing CYP19A1 translation and oestrogen synthesis.

BACKGROUND: METTL3 plays a significant role as a catalytic enzyme in mediating N6-methyladenosine (m6A) modification, and its importance in tumour progression has been extensively studied in recent years. However, the precise involvement of METTL3 in the regulation of translation in non-small cell lung cancer (NSCLC) remains unclear. RESULTS: Here we discovered by clinical investigation that METTL3 expression is correlated with NSCLC metastasis. Ablation of METTL3 in NSCLC cells inhibits invasion and metastasis in vitro and in vivo. Subsequently, through translatomics data mining and experimental validation, we demonstrated that METTL3 enhances the translation of aromatase (CYP19A1), a key enzyme in oestrogen synthesis, thereby promoting oestrogen production and mediating the invasion and metastasis of NSCLC. Mechanistically, METTL3 interacts with translation initiation factors and binds to CYP19A1 mRNA, thus enhancing the translation efficiency of CYP19A1 in an m6A-dependent manner. Pharmacological inhibition of METTL3 enzymatic activity or translation initiation factor eIF4E abolishes CYP19A1 protein synthesis. CONCLUSIONS: Our findings indicate the crucial role of METTL3-mediated translation regulation in NSCLC and reveal the significance of METTL3/eIF4E/CYP19A1 signaling as a promising therapeutic target for anti-metastatic strategies against NSCLC.

A risk score combining co-expression modules related to myeloid cells and alternative splicing associates with response to PD-1/PD-L1 blockade in non-small cell lung cancer.

Background: Comprehensive analysis of transcriptomic profiles of non-small cell lung cancer (NSCLC) may provide novel evidence for biomarkers associated with response to PD-1/PD-L1 immune checkpoint blockade (ICB). Methods: We utilized weighted gene co-expression network analysis (WGCNA) to analyze transcriptomic data from two NSCLC datasets from Gene Expression Omnibus (GSE135222 and GSE126044) that involved patients received ICB treatment. We evaluated the correlation of co-expression modules with ICB responsiveness and functionally annotated ICB-related modules using pathway enrichment analysis, single-cell RNA sequencing, flow cytometry and alternative splicing analysis. We built a risk score using Lasso-COX regression based on hub genes from ICB-related modules. We investigated the alteration of tumor microenvironment between high- and low- risk groups and the association of the risk score with previously established predictive biomarkers. Results: Our results identified a black with positive correlation and a blue module with negative correlation to ICB responsiveness. The black module was enriched in pathway of T cell activation and antigen processing and presentation, and the genes assigned to it were consistently expressed on myeloid cells. We observed decreased alternative splicing events in samples with high signature scores of the blue module. The Lasso-COX analysis screened out three genes (EVI2B, DHX9, HNRNPM) and constructed a risk score from the hub genes of the two modules. We validated the predictive value of the risk score for poor response to ICB therapy in an in-house NSCLC cohort and a pan-cancer cohort from the KM-plotter database. The low-risk group had more immune-infiltrated microenvironment, with higher frequencies of precursor exhausted CD8+ T cells, tissue-resident CD8+ T cells, plasmacytoid dendritic cells and type 1 conventional dendritic cells, and a lower frequency of terminal exhausted CD8+ T cells, which may explain its superior response to ICB therapy. The significant correlation of the risk score to gene signature of tertiary lymphoid structure also implicated the possible mechanism of this predictive biomarker. Conclusions: Our study identified two co-expression modules related to ICB responsiveness in NSCLC and developed a risk score accordingly, which could potentially serve as a predictive biomarker for ICB response.

Effects and translatomics characteristics of a small-molecule inhibitor of METTL3 against non-small cell lung cancer.

In non-small cell lung cancer (NSCLC), the heterogeneity promotes drug resistance, and the restricted expression of programmed death-ligand 1 (PD-L1) limits the immunotherapy benefits. Based on the mechanisms related to translation regulation and the association with PD-L1 of methyltransferase-like 3 (METTL3), the novel small-molecule inhibitor STM2457 is assumed to be useful for the treatment of NSCLC. We evaluated the efficacy of STM2457 in vivo and in vitro and confirmed the effects of its inhibition on disease progression. Next, we explored the effect of STM2457 on METTL3 and revealed its effects on the inhibition of catalytic activity and upregulation of METTL3 protein expression. Importantly, we described the genome-wide characteristics of multiple omics data acquired from RNA sequencing, ribosome profiling, and methylated RNA immunoprecipitation sequencing data under STM2457 treatment or METTL3 knockout. We also constructed a model for the regulation of the translation of METTL3 and PD-L1. Finally, we found PD-L1 upregulation by STM2457 in vivo and in vitro. In conclusion, STM2457 is a potential novel suppressor based on its inhibitory effect on tumor progression and may be able to overcome the heterogeneity based on its impact on the translatome. Furthermore, it can improve the immunotherapy outcomes based on PD-L1 upregulation in NSCLC.

ERß promoted invadopodia formation-mediated non-small cell lung cancer metastasis via the ICAM1/p-Src/p-Cortactin signaling pathway.

In a previous study, our research group observed that estrogen promotes the metastasis of non-small cell lung cancer (NSCLC) through the estrogen receptor ß (ERß). Invadopodia are key structures involved in tumor metastasis. However, it is unclear whether ERß is involved in the promotion of NSCLC metastasis through invadopodia. In our study, we used scanning electron microscopy to observe the formation of invadopodia following the overexpression of ERß and treatment with E2. In vitro experiments using multiple NSCLC cell lines demonstrated that ERß can increase the formation of invadopodia and cell invasion. Mechanistic studies revealed that ERß can upregulate the expression of ICAM1 by directly binding to estrogen-responsive elements (EREs) located on the ICAM1 promoter, which in turn can enhance the phosphorylation of Src/cortactin. We also confirmed these findings in vivo using an orthotopic lung transplantation mouse model, which validated the results obtained from the in vitro experiments. Finally, we examined the expressions of ERß and ICAM1 using immunohistochemistry in both NSCLC tissue and paired metastatic lymph nodes. The results confirmed that ERß promotes the formation of invadopodia in NSCLC cells through the ICAM1/p-Src/p-Cortactin signaling pathway.

Stearoyl-CoA Desaturases1 Accelerates Non-Small Cell Lung Cancer Metastasis by Promoting Aromatase Expression to Improve Estrogen Synthesis.

Metastases contribute to the low survival rate of non-small cell lung cancer (NSCLC) patients. Targeting lipid metabolism for anticancer therapies is attractive. Accumulative evidence shows that stearoyl-CoA desaturases1 (SCD1), a key enzyme in lipid metabolism, enables tumor metastasis and the underlying mechanism remains unknown. In this study, immunohistochemical staining of 96 clinical specimens showed that the expression of SCD1 was increased in tumor tissues (p < 0.001). SCD1 knockdown reduced the migration and invasion of HCC827 and PC9 cells in transwell and wound healing assays. Aromatase (CYP19A1) knockdown eliminated cell migration and invasion caused by SCD1 overexpression. Western blotting assays demonstrated that CYP19A1, along with ß-catenin protein levels, was reduced in SCD1 knocked-down cells, and estrogen concentration was reduced (p < 0.05) in cell culture medium measured by enzyme-linked immunosorbent assay. SCD1 overexpression preserving ß-catenin protein stability was evaluated by coimmunoprecipitation and Western blotting. The SCD1 inhibitor A939572, and a potential SCD1 inhibitor, grape seed extract (GSE), significantly inhibited cell migration and invasion by blocking SCD1 and its downstream ß-catenin, CYP19A1 expression, and estrogen concentration. In vivo tumor formation assay and a tail vein metastasis model indicated that knockdown of SCD1 blocked tumor growth and metastasis. In conclusion, SCD1 could accelerate metastasis by maintaining the protein stability of ß-catenin and then promoting CYP19A1 transcription to improve estrogen synthesis. SCD1 is expected to be a promised therapeutic target, and its novel inhibitor, GSE, has great therapeutic potential in NSCLC.

The diverse role of RNA methylation in esophageal cancer.

Esophageal cancer is one of the major life-threatening diseases in the world. RNA methylation is the most common post-transcriptional modification and a wide-ranging regulatory system controlling gene expression. Numerous studies have revealed that dysregulation of RNA methylation is critical for cancer development and progression. However, the diverse role of RNA methylation and its regulators in esophageal cancer remains to be elucidated and summarized. In this review, we focus on the regulation of major RNA methylation, including m 6A, m 5C, and m 7G, as well as the expression patterns and clinical implications of its regulators in esophageal cancer. We systematically summarize how these RNA modifications affect the "life cycle" of target RNAs, including mRNA, microRNA, long non-coding RNA, and tRNA. The downstream signaling pathways associated with RNA methylation during the development and treatment of esophageal cancer are also discussed in detail. Further studies on how these modifications function together in the microenvironment of esophageal cancer will draw a clearer picture of the clinical application of novel and specific therapeutic strategies.

A five-gene expression signature of centromeric proteins with prognostic value in lung adenocarcinoma.

Background: Centromere proteins (CENPs) form a large protein family. Sixteen proteins in this family are positioned at the centromere throughout the cell cycle. The overexpression of CENPs is common in many cancers and predicts a poor prognosis. However, a comprehensive analysis of CENPs expression has not been conducted, and their clinical significance in lung adenocarcinoma (LUAD) is unclear. Methods: We investigated the expression differences of the CENP family in LUAD using The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) cohorts. Kaplan-Meier curve survival analysis was performed to assess their independent prognostic values. We then tested 5 clinical LUAD specimens by quantitative real time polymerase chain reaction (qRT-PCR). The risk model was constructed with least absolute shrinkage and selection operator (LASSO). Cox regression analyses were carried out to determine independent prognostic indicators. Weighted gene coexpression network analysis (WGCNA) was employed to define the coexpression networks. Results: The messenger RNA (mRNA) expression of 15 differential CENP proteins was higher in LUAD than in normal lung tissues. Among them, 10 CENP proteins had significant prognostic value. The risk model comprising CENPF, CENPU, CENPM, CENPH, and CENPW showed a significant correlation [hazard ratio (HR) 1.75, 95% confidence interval (CI): 1.3-2.35; P=2e-04]. However, the prognostic accuracy was not strong [1-year survival: area under curve (AUC) 0.63; 3-year survival: AUC 0.62; 5-year survival: AUC 0.6]. The qRT-PCR results showed that the 5 CENPs were upregulated in LUAD tissues compared to in normal lung tissues. A total of 441 hub genes coexpressed with the 5 CENPs were identified. Conclusions: CENPF, CENPU, CENPM, CENPH, and CENPW have prognostic values and may be potential targets for LUAD treatment.

Critical Roles of METTL3 in Translation Regulation of Cancer.

Aberrant translation, a characteristic feature of cancer, is regulated by the complex and sophisticated RNA binding proteins (RBPs) in the canonical translation machinery. N6-methyladenosine (m6A) modifications are the most abundant internal modifications in mRNAs mediated by methyltransferase-like 3 (METTL3). METTL3 is commonly aberrantly expressed in different tumors and affects the mRNA translation of many oncogenes or dysregulated tumor suppressor genes in a variety of ways. In this review, we discuss the critical roles of METTL3 in translation regulation and how METTL3 and m6A reader proteins in collaboration with RBPs within the canonical translation machinery promote aberrant translation in tumorigenesis, providing an overview of recent efforts aiming to 'translate' these results to the clinic.

Identification and validation of DPY30 as a prognostic biomarker and tumor immune microenvironment infiltration characterization in esophageal cancer.

Esophageal cancer (ESCA) is a lethal malignancy and is associated with the alterations of various genes and epigenetic modifications. The protein dpy-30 homolog (DPY30) is a core member of histone H3K4 methylation catalase and its dysfunction is associated with the occurrence and development of cancer. Therefore, the present study investigated the role of DPY30 in ESCA and evaluated the association between the expression of DPY30, the clinicopathological characteristics of ESCA and the tumor immune microenvironment. It conducted a comprehensive analysis of DPY30 in patients with ESCA using The Cancer Genome Atlas (TCGA) database and clinical tissue microarray specimens of ESCA. Immunohistochemistry was performed to assess the expression levels of DPY30 in tissues. Receiver operating curve analysis, Kaplan-Meier survival analysis and Cox regression analysis were performed to identify the diagnostic and prognostic value of DPY30. Gene Set Enrichment Analysis, protein-protein interaction network and Estimation of Stromal and Immune cells in Malignant Tumor tissues using the Expression data were used to screen DPY30-associated genes and evaluate the immune score of the TCGA samples. The results demonstrated that the expression of mRNA and protein levels of DPY30 were significantly upregulated in tumor tissues compared with normal tissue samples. The expression of DPY30 was closely associated with the poor prognosis of patients with ESCA. The present study also found that DPY30 expression and the pathological characteristics of ESCA were significantly correlated. Additionally, the expression of DPY30 demonstrated a significant positive correlation with various immune cells infiltration. The results suggested that DPY30 might influence tumor immune infiltration. In conclusion, the findings suggested that DPY30 might be a potential prognostic biomarker and an immunotherapeutic target in ESCA.

Enhanced anti-breast cancer efficacy of co-delivery liposomes of docetaxel and curcumin.

The successful treatment of breast cancer is hampered by toxicity to normal cells, impaired drug accumulation at the tumor site, and multidrug resistance. We designed a novel multifunctional liposome, CUR-DTX-L, to co-deliver curcumin (CUR) and the chemotherapeutic drug docetaxel (DTX) for the treatment of breast cancer in order to address multidrug resistance (MDR) and the low efficacy of chemotherapy. The mean particle size, polydispersity index, zeta potential, and encapsulation efficiency of CUR-DTX-L were 208.53 ± 6.82 nm, 0.055 ± 0.001, -23.1 ± 2.1 mV, and 98.32 ± 2.37%, respectively. An in vitro release study and CCK-8 assays showed that CUR-DTX-L has better sustained release effects and antitumor efficacy than free drugs, the antitumor efficacy was verified by MCF-7 tumor-bearing mice, the CUR-DTX-L showed better antitumor efficacy than other groups, and the in vivo pharmacokinetic study indicated that the plasma concentration-time curve, mean residence time, and biological half-life time of CUR-DTX-L were significantly increased compared with free drugs, suggesting that it is a promising drug delivery system for the synergistic treatment of breast cancer.

The Prognostic Value of Bone Morphogenetic Proteins and Their Receptors in Lung Adenocarcinoma.

BACKGROUND: Bone morphogenetic proteins (BMPs) regulate tumor progression via binding to their receptors (BMPRs). However, the expression and clinical significance of BMPs/BMPRs in lung adenocarcinoma remain unclear due to a lack of systematic studies. METHODS: This study screened differentially expressed BMPs/BMPRs (deBMPs/BMPRs) in a training dataset combining TCGA-LUAD and GTEx-LUNG and verified them in four GEO datasets. Their prognostic value was evaluated via univariate and multivariate Cox regression analyses. LASSO was performed to construct an initial risk model. Subsequently, after weighted gene co-expression network analysis (WGCNA), differential expression analysis, and univariate Cox regression analysis, hub genes co-expressed with differentially expressed BMPs/BMPRs were filtered out to improve the risk model and explore potential mechanisms. The improved risk model was re-established via LASSO combining hub genes with differentially expressed BMPs/BMPRs as the core. In the testing cohort including 93 lung adenocarcinoma patients, immunohistochemistry (IHC) was performed to verify BMP5 protein expression and its association with prognosis. RESULTS: BMP2, BMP5, BMP6, GDF10, and ACVRL1 were verified as downregulated in lung adenocarcinoma. Survival analysis identified BMP5 as an independent protective prognostic factor. We also found that BMP5 was significantly correlated with EGFR expression and mutations, suggesting that BMP5 may play a role in targeted therapy. The initial risk model containing only BMP5 showed a significant correlation (HR: 1.71, 95% CI: 1.28-2.28, p: 3e-04) but low prognostic accuracy (AUC of 1-year survival: 0.6, 3-year survival: 0.6, 5-year survival: 0.63). Seventy-nine hub genes co-expressed with BMP5 were identified, and their functions were enriched in cell migration and tumor metastasis. The re-established risk model showed greater prognostic correlation (HR: 2.58, 95% CI: 1.92-3.46, p: 0) and value (AUC of 1-year survival: 0.72, 3-year survival: 0.69, and 5-year survival: 0.68). IHC results revealed that BMP5 protein was also downregulated in lung adenocarcinoma and higher expression was markedly associated with better prognosis (HR: 0.44, 95% CI: 0.23-0.85, p: 0.0145). CONCLUSION: BMP5 is a potential crucial target for lung adenocarcinoma treatment based on significant differential expression and superior prognostic value.

Upregulation of estrogen receptor beta protein but not mRNA predicts poor prognosis and may be associated with enhanced translation in non-small cell lung cancer: a systematic review and meta-analysis.

BACKGROUND: An increasing number of original studies suggest that estrogen receptor beta (ERß) expression may be related to non-small cell lung cancer (NSCLC) prognosis; however, the evidence remains inconclusive and conflicting. We aimed to systematically evaluate the expression and prognostic value of ERß in NSCLC, and to explain the inconsistency between ERß protein and mRNA level. METHODS: PubMed, Embase, and Web of Science databases were searched for studies (published before October 6, 2020) reporting the prognostic value of ERß protein expression in NSCLC. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) for overall survival (OS) were calculated. Transcriptome and survival data of lung adenocarcinoma patients were obtained from public databases for differential expression and survival analyses. Immunohistochemistry (IHC) was performed to examine the ERß protein expression in 39 NSCLC patients. Western blotting and RT-qPCR were performed to analyze ERß expression in two paired NSCLC and normal adjacent tissue samples. The effect of methyltransferase-like 13 (METTL3) on ERß expression was investigated in a lung cancer cell line. RESULTS: Meta-analysis of 23 studies with a total of 3744 patients demonstrated that high protein expression of overall ERß and cytoplasmic ERß indicated poor OS (HR: 1.05, 95% CI: 1.00 to 1.10; HR: 1.48, 95% CI: 1.13 to 1.95) in NSCLC. For lung adenocarcinoma especially, high protein expression of both overall/cytoplasmic ERß and nuclear ERß suggested poor OS (HR: 1.54, 95% CI: 1.05 to 2.25; HR: 1.36, 95% CI: 1.03 to 1.80). Bioinformatics analysis indicated the expression of ERß mRNA was not associated with the prognosis of lung adenocarcinoma. Analysis of public databases showed that ERß mRNA is not highly expressed in tumor tissues, however, IHC results revealed that ERß protein is highly expressed in NSCLC tissues. We validated this inconsistency in ERß expression in paired tumors and normal adjacent tissues from patients. Moreover, METTL3 knockdown in the A549 cell line downregulated ERß protein expression but not ERß mRNA expression. CONCLUSIONS: Our study elucidated the inconsistency between ERß protein and mRNA expression levels and their prognostic values. The results indicated that METTL3-driven enhanced translation in NSCLC may cause this inconsistency.