EEF1A2 triggers stronger ERK mediated metastatic program in ER negative breast cancer cells than in ER positive cells

Ac4C modification of lncRNA SIMALR promotes nasopharyngeal carcinoma progression through activating eEF1A2 to facilitate ITGB4/ITGA6 translation

The dysregulation of long non-coding RNAs (lncRNAs) are involved in regulating tumor progression in multiple manner. However, little is known about whether lncRNA is involved in the translation regulation of proteins. Here, we identified that the suppressor of inflammatory macrophage apoptosis lncRNA (SIMALR) was highly expressed in nasopharyngeal carcinoma (NPC) tissues by analyzing the lncRNA microarray. Clinically, the high expression of SIMALR served as an independent predictor for inferior prognosis in NPC patients. SIMALR functioned as an oncogenic lncRNA that promoted the proliferation and metastasis of NPC cells in vitro and in vivo. Mechanistically, SIMALR served as a critical accelerator of protein synthesis by binding to eEF1A2 (eukaryotic translation elongation factor 1 alpha 2), one of the most crucial regulators in the translation machinery of the eukaryotic cells, and enhancing its endogenous GTPase activity. Furthermore, SIMALR mediated the activation of eEF1A2 phosphorylation to accelerate the translation of ITGB4/ITGA6, ultimately promoting the malignant phenotype of NPC cells. In addition, N-acetyltransferase 10 (NAT10) enhanced the stability of SIMALR and caused its overexpression in NPC through the N4-acetylcytidine (ac4C) modification. In sum, our results illustrate SIMALR functions as an accelerator for protein translation and highlight the oncogenic role of NAT10-SIMALR-eEF1A2-ITGB4/6 axis in NPC.

Identification of anoikis-related gene signatures and construction of the prognosis model in prostate cancer

Background

One of the primary reasons for tumor invasion and metastasis is anoikis resistance. Biochemical recurrence (BCR) of prostate cancer (PCa) serves as a harbinger of its distant metastasis. However, the role of anoikis in PCa biochemical recurrence has not been fully elucidated.

Methods

Differential expression analysis was used to identify anoikis-related genes based on the TCGA and GeneCards databases. Prognostic models were constructed utilizing LASSO regression, univariate and multivariate Cox regression analyses. Moreover, Gene Expression Omnibus datasets (GSE70770 and GSE46602) were applied as validation cohorts. Gene Ontology, KEGG and GSVA were utilized to explore biological pathways and molecular mechanisms. Further, immune profiles were assessed using CIBERSORT, ssGSEA, and TIDE, while anti-cancer drugs sensitivity was analyzed by GDSC database. In addition, gene expressions in the model were examined using online databases (Human Protein Atlas and Tumor Immune Single-Cell Hub).

Results

113 differentially expressed anoikis-related genes were found. Four genes (EEF1A2, RET, FOSL1, PCA3) were selected for constructing a prognostic model. Using the findings from the Cox regression analysis, we grouped patients into groups of high and low risk. The high-risk group exhibited a poorer prognosis, with a maximum AUC of 0.897. Moreover, larger percentage of immune infiltration of memory B cells, CD8 Tcells, neutrophils, and M1 macrophages were observed in the high-risk group than those in the low-risk group, whereas the percentage of activated mast cells and dendritic cells in the high-risk group were lower. An increased TIDE score was founded in the high-risk group, suggesting reduced effectiveness of ICI therapy. Additionally, the IC50 results for chemotherapy drugs indicated that the low-risk group was more sensitive to most of the drugs. Finally, the genes EEF1A2, RET, and FOSL1 were expressed in PCa cases based on HPA website. The TISCH database suggested that these four ARGs might contribute to the tumor microenvironment of PCa.

Conclusion

We created a risk model utilizing four ARGs that effectively predicts the risk of BCR in PCa patients. This study lays the groundwork for risk stratification and predicting survival outcomes in PCa patients with BCR.

The eEF1A protein in cancer: Clinical significance, oncogenic mechanisms, and targeted therapeutic strategies

Eukaryotic elongation factor 1A (eEF1A) is among the most abundant proteins in eukaryotic cells. Evolutionarily conserved across species, eEF1A is in charge of translation elongation for protein biosynthesis as well as a plethora of non-translational moonlighting functions for cellular homeostasis. In malignant cells, however, eEF1A becomes a pleiotropic driver of cancer progression via a broad diversity of pathways, which are not limited to hyperactive translational output. In the past decades, mounting studies have demonstrated the causal link between eEF1A and carcinogenesis, gaining deeper insights into its multifaceted mechanisms and corroborating its value as a prognostic marker in various cancers. On the other hand, an increasing number of natural and synthetic compounds were discovered as anticancer eEF1A-targeting inhibitors. Among them, plitidepsin was approved for the treatment of multiple myeloma whereas metarrestin was currently under clinical development. Despite significant achievements in these two interrelated fields, hitherto there lacks a systematic examination of the eEF1A protein in the context of cancer research. Therefore, the present work aims to delineate its clinical implications, molecular oncogenic mechanisms, and targeted therapeutic strategies as reflected in the ever expanding body of literature, so as to deepen mechanistic understanding of eEF1A-involved tumorigenesis and inspire the development of eEF1A-targeted chemotherapeutics and biologics.

Endocardial HDAC3 is required for myocardial trabeculation

Failure of proper ventricular trabeculation is often associated with congenital heart disease. Support from endocardial cells, including the secretion of extracellular matrix and growth factors is critical for trabeculation. However, it is poorly understood how the secretion of extracellular matrix and growth factors is initiated and regulated by endocardial cells. We find that genetic knockout of histone deacetylase 3 in the endocardium in mice results in early embryo lethality and ventricular hypotrabeculation. Single cell RNA sequencing identifies significant downregulation of extracellular matrix components in histone deacetylase 3 knockout endocardial cells. Secretome from cultured histone deacetylase 3 knockout mouse cardiac endothelial cells lacks transforming growth factor ß3 and shows significantly reduced capacity in stimulating cultured cardiomyocyte proliferation, which is remarkably rescued by transforming growth factor ß3 supplementation. Mechanistically, we identify that histone deacetylase 3 knockout induces transforming growth factor ß3 expression through repressing microRNA-129-5p. Our findings provide insights into the pathogenesis of congenital heart disease and conceptual strategies to promote myocardial regeneration.

Endocardial HDAC3 is required for myocardial trabeculation

BACKGROUND

Trabeculation, a key process in early heart development, is the formation of myocardial trabecular meshwork. The failure of trabeculation often leads to embryonic lethality. Support from endocardial cells, including the secretion of extracellular matrix (ECM) and growth factors is critical for trabeculation; however, it is unknown how the secretion of ECM and growth factors is initiated and regulated by endocardial cells.

METHODS

Various cellular and mouse models in conjunction with biochemical and molecular tools were employed to study the role of histone deacetylase 3 (HDAC3) in the developing endocardium.

RESULTS

We found that genetic deletion of Hdac3 in endocardial cells in mice resulted in early embryo lethality presenting as a hypotrabeculation cardiac phenotype. Single cell RNA sequencing identified several ECM components including collagens that were significantly downregulated in Hdac3 knockout (KO) endocardial cells. When cultured with supernatant from Hdac3 KO mouse cardiac endothelial cells (MCECs), wild-type mouse embryonic cardiomyocytes showed decreased proliferation, suggesting that growth signaling from Hdac3 KO MCECs is disrupted. Subsequent transcriptomic analysis revealed that transforming growth factor β3 (TGFβ3) was significantly downregulated in Hdac3 KO MCECs and Hdac3 cardiac endothelial KO hearts. Mechanistically, we identified that microRNA (miR)-129-5p was significantly upregulated in Hdac3 KO MCECs and Hdac3 cardiac endothelial KO hearts. Overexpression of miR-129-5p repressed Tgfβ3 expression in wild-type MCECs, whereas knockdown of miR-129-5p restored Tgfβ3 expression in Hdac3 KO MCECs.

CONCLUSION

Our findings reveal a critical signaling pathway in which endocardial HDAC3 promotes trabecular myocardium growth by stimulating TGFβ signaling through repressing miR-129-5p, providing novel insights into the etiology of congenital heart disease and conceptual strategies to promote myocardial regeneration.

A pan-cancer analysis of the prognosis and immune infiltration of eEF1A2 and its potential function in thyroid carcinoma

Purpose

Eukaryotic translation elongation factor 1α2 (eEF1A2) promotes tumour progression in various cancers. We performed a pan-cancer analysis of eEF1A2 and explored its role in thyroid carcinoma (THCA).

Methods

Databases from The Cancer Genome Atlas (TCGA), the University of Alabama at Birmingham Cancer data analysis Portal (UALCAN), and the Human Protein Atlas (HPA) were used to investigate the differential expression of eEF1A2 in pan-cancer. The pathological stage, prognostic characteristics, tumour microenvironment (TME), tumour mutational burden (TMB), and microsatellite instability (MSI) were analysed in diverse tumours with different expression levels of eEF1A2. The expression levels in papillary thyroid carcinoma (PTC) and its specific role in cell proliferation, migration, invasion, and cell glycolysis in PTC cells were verified by quantitative real time polymerase chain reaction (qRT-PCR), immunohistochemistry, cell counting kit-8, colony formation, wound healing, Transwell assay, and lactate acid and glucose assays.Results:eEF1A2 was differentially expressed in various malignant tumour tissues compared to control tissues and was associated with poor pathological stage and prognosis in most types of tumours. Moreover, eEF1A2 expression closely correlated with the infiltration of immunosuppressive cells, TMB, and MSI in some tumour types. Expression of eEF1A2 in PTC is higher than the para-carcinoma, and eEF1A2 downregulation suppressed TPC-1 and BCPAP cell proliferation, migration, invasion, and glycolysis.

Conclusion

Our study suggests that the expression of eEF1A2 is related to the prognosis and immune infiltration of some tumours and may be a predictor of prognosis and immunotherapy. eEF1A2 could promote malignant behaviour of PTC cells.

EEF1A2 promotes HIF1A mediated breast cancer angiogenesis in normoxia and participates in a positive feedback loop with HIF1A in hypoxia

BACKGROUND

The eukaryotic elongation factor, EEF1A2, has been identified as an oncogene in various solid tumors. Here, we have identified a novel function of EEF1A2 in angiogenesis.

METHODS

Chick chorioallantoic membrane, tubulogenesis, aortic ring, Matrigel plug, and skin wound healing assays established EEF1A2's role in angiogenesis.

RESULT

Higher EEF1A2 levels in breast cancer cells enhanced cell growth, movement, blood vessel function, and tubule formation in HUVECs, as confirmed by ex-ovo and in-vivo tests. The overexpression of EEF1A2 could be counteracted by Plitidepsin. Under normoxic conditions, EEF1A2 triggered HIF1A expression via ERK-Myc and mTOR signaling in TNBC and ER/PR positive cells. Hypoxia induced the expression of EEF1A2, leading to a positive feedback loop between EEF1A2 and HIF1A. Luciferase assay and EMSA confirmed HIF1A binding on the EEF1A2 promoter, which induced its transcription. RT-PCR and polysome profiling validated that EEF1A2 affected VEGF transcription and translation positively. This led to increased VEGF release from breast cancer cells, activating ERK and PI3K-AKT signaling in endothelial cells. Breast cancer tissues with elevated EEF1A2 showed higher microvessel density.

CONCLUSION

EEF1A2 exhibits angiogenic potential in both normoxic and hypoxic conditions, underscoring its dual role in promoting EMT and angiogenesis, rendering it a promising target for cancer therapy.

Oncogenic activation of EEF1A2 expression: a journey from a putative to an established oncogene

Protein synthesis via translation is a central process involving several essential proteins called translation factors. Although traditionally described as cellular "housekeepers," multiple studies have now supported that protein initiation and elongation factors regulate cell growth, apoptosis, and tumorigenesis. One such translation factor is eukaryotic elongation factor 1 alpha 2 (EEF1A2), a member of the eukaryotic elongation factor family, which has a canonical role in the delivery of aminoacyl-tRNA to the A-site of the ribosome in a guanosine 5'-triphosphate (GTP)-dependent manner. EEF1A2 differs from its closely related isoform, EEF1A1, in tissue distribution. While EEF1A1 is present ubiquitously, EEF1A2 replaces it in specialized tissues. The reason why certain specialized tissues need to essentially switch EEF1A1 expression altogether with EEF1A2 remains to be answered. Abnormal "switch on" of the EEF1A2 gene in normal tissues is witnessed and is seen as a cause of oncogenic transformation in a wide variety of solid tumors. This review presents the journey of finding increased expression of EEF1A2 in multiple cancers, establishing molecular mechanism, and exploring it as a target for cancer therapy. More precisely, we have compiled studies in seven types of cancers that have reported EEF1A2 overexpression. We have discussed the effect of aberrant EEF1A2 expression on the oncogenic properties of cells, signaling pathways, and interacting partners of EEF1A2. More importantly, in the last part, we have discussed the unique potential of EEF1A2 as a therapeutic target. This review article gives an up-to-date account of EEF1A2 as an oncogene and can draw the attention of the scientific community, attracting more research.

Understanding functions of eEF1 translation elongation factors beyond translation. A proteomic approach

Mammalian translation elongation factors eEF1A1 and eEF1A2 are 92% homologous isoforms whose mutually exclusive tissue-specific expression is regulated during development. The isoforms have similar translation functionality, but show differences in spatial organization and participation in various processes, such as oncogenesis and virus reproduction. The differences may be due to their ability to interact with isoform-specific partner proteins. We used the identified sets of eEF1A1 or eEF1A2 partner proteins to identify cell complexes and/or processes specific to one particular isoform. As a result, we found isoform-specific interactions reflecting the involvement of different eEF1A isoforms in different cellular processes, including actin-related, chromatin-remodeling, ribonuclease H2, adenylyl cyclase, and Cul3-RING ubiquitin ligase complexes as well as initiation of mitochondrial transcription. An essential by-product of our analysis is the elucidation of a number of cellular processes beyond protein biosynthesis, where both isoforms appear to participate such as large ribosomal subunit biogenesis, mRNA splicing, DNA mismatch repair, 26S proteasome activity, P-body and exosomes formation, protein targeting to the membrane. This information suggests that a relatively high content of eEF1A in the cell may be necessary not only to maintain efficient translation, but also to ensure its participation in various cellular processes, where some roles of eEF1A have not yet been described. We believe that the data presented here will be useful for deciphering new auxiliary functions of eEF1A and its isoforms, and provide a new look at the known non-canonical functions of this main component of the human translation-elongation machinery.

The role of dysregulated mRNA translation machinery in cancer pathogenesis and therapeutic value of ribosome-inactivating proteins

Dysregulated protein synthesis is a hallmark of tumors. mRNA translation reprogramming contributes to tumorigenesis, which is fueled by abnormalities in ribosome formation, tRNA abundance and modification, and translation factors. Not only malignant cells but also stromal cells within tumor microenvironment can undergo transformation toward tumorigenic phenotypes during translational reprogramming. Ribosome-inactivating proteins (RIPs) have garnered interests for their ability to selectively inhibit protein synthesis and suppress tumor growth. This review summarizes the role of dysregulated translation machinery in tumor development and explores the potential of RIPs in cancer treatment.

Comparison Study of Small Extracellular Vesicle Isolation Methods for Profiling Protein Biomarkers in Breast Cancer Liquid Biopsies

Small extracellular vesicles (sEVs) are an important intercellular communicator, participating in all stages of cancer metastasis, immunity, and therapeutic resistance. Therefore, protein cargoes within sEVs are considered as a superior source for breast cancer (BC) biomarker discovery. Our study aimed to optimise the approach for sEV isolation and sEV proteomic analysis to identify potential sEV protein biomarkers for BC diagnosis. sEVs derived from BC cell lines, BC patients' plasma, and non-cancer controls were isolated using ultracentrifugation (UC), a Total Exosome Isolation kit (TEI), and a combined approach named UCT. In BC cell lines, the UC isolates showed a higher sEV purity and marker expression, as well as a higher number of sEV proteins. In BC plasma samples, the UCT isolates showed the highest proportion of sEV-related proteins and the lowest percentage of lipoprotein-related proteins. Our data suggest that the assessment of both the quantity and quality of sEV isolation methods is important in selecting the optimal approach for the specific sEV research purpose, depending on the sample types and downstream analysis.

SADLN: Self-attention based deep learning network of integrating multi-omics data for cancer subtype recognition

Integrating multi-omics data for cancer subtype recognition is an important task in bioinformatics. Recently, deep learning has been applied to recognize the subtype of cancers. However, existing studies almost integrate the multi-omics data simply by concatenation as the single data and then learn a latent low-dimensional representation through a deep learning model, which did not consider the distribution differently of omics data. Moreover, these methods ignore the relationship of samples. To tackle these problems, we proposed SADLN: A self-attention based deep learning network of integrating multi-omics data for cancer subtype recognition. SADLN combined encoder, self-attention, decoder, and discriminator into a unified framework, which can not only integrate multi-omics data but also adaptively model the sample's relationship for learning an accurately latent low-dimensional representation. With the integrated representation learned from the network, SADLN used Gaussian Mixture Model to identify cancer subtypes. Experiments on ten cancer datasets of TCGA demonstrated the advantages of SADLN compared to ten methods. The Self-Attention Based Deep Learning Network (SADLN) is an effective method of integrating multi-omics data for cancer subtype recognition.

Reduced expression of FRG1 facilitates breast cancer progression via GM-CSF/MEK-ERK axis by abating FRG1 mediated transcriptional repression of GM-CSF

Multiple molecular subtypes and distinct clinical outcomes in breast cancer, necessitate specific therapy. Moreover, despite the improvements in breast cancer therapy, it remains the fifth cause of cancer-related deaths, indicating the involvement of unknown genes. To identify novel contributors and molecular subtype independent therapeutic options, we report reduced expression of FRG1 in breast cancer patients, which regulates GM-CSF expression via direct binding to its promoter. Reduction in FRG1 expression enhanced EMT and increased cell proliferation, migration, and invasion, in breast cancer cell lines. Loss of FRG1 increased GM-CSF levels which activated MEK/ERK axis and prevented apoptosis by inhibiting p53 in an ERK-dependent manner. FRG1 depletion in the mouse model increased tumor volume, phospho-ERK, and EMT marker levels. The therapeutic potential of anti-GM-CSF therapy was evident by reduced tumor size, when tumors with decreased FRG1 were treated with anti-GM-CSF mAb. We found an inverse expression pattern of FRG1 and phospho-ERK levels in breast cancer patient tissues, corroborating the in vitro and mouse model-based findings. Our findings first time elucidate the role of FRG1 as a metastatic suppressor of breast cancer by regulating the GM-CSF/MEK-ERK axis.

Aberrant protein synthesis and cancer development: The role of canonical eukaryotic initiation, elongation and termination factors in tumorigenesis

In tumourigenesis, oncogenes or dysregulated tumour suppressor genes alter the canonical translation machinery leading to a reprogramming of the translatome that, in turn, promotes the translation of selected mRNAs encoding proteins involved in proliferation and metastasis. It is therefore unsurprising that abnormal expression levels and activities of eukaryotic initiation factors (eIFs), elongation factors (eEFs) or termination factors (eRFs) are associated with poor outcome for patients with a wide range of cancers. In this review we discuss how RNA binding proteins (RBPs) within the canonical translation factor machinery are dysregulated in cancers and how targeting such proteins is leading to new therapeutic avenues.

P2Y2 promotes fibroblasts activation and skeletal muscle fibrosis through AKT, ERK, and PKC

BACKGROUND

Skeletal muscle atrophy and fibrosis are pathological conditions that contribute to morbidity in numerous conditions including aging, cachexia, and denervation. Muscle atrophy is characterized as reduction of muscle fiber size and loss of muscle mass while muscle fibrosis is due to fibroblasts activation and excessive production of extracellular matrix. Purinergic receptor P2Y2 has been implicated in fibrosis. This study aims to elucidate the roles of P2Y2 in sleketal muscle atrophy and fibrosis.

METHODS

Primary muscle fibroblasts were isolated from wild type and P2Y2 knockout (KO) mice and their proliferating and migrating abilities were assessed by CCK-8 and Transwell migration assays respectively. Fibroblasts were activated with TGF-β1 and assessed by western blot of myofibroblast markers including α-SMA, CTGF, and collagen I. Muscle atrophy and fibrosis were induced by transection of distal sciatic nerve and assessed using Masson staining.

RESULTS

P2Y2 KO fibroblasts proliferated and migrated significantly slower than WT fibroblasts with or without TGF-β1.The proliferation and ECM production were enhanced by P2Y2 agonist PSB-1114 and inhibited by antagonist AR-C118925. TGF-β1 induced fibrotic activation was abolished by P2Y2 ablation and inhibited by AKT, ERK, and PKC inhibitors. Ablation of P2Y2 reduced denervation induced muscle atrophy and fibrosis.

CONCLUSIONS

P2Y2 is a promoter of skeletal muscle atrophy and activation of fibroblasts after muscle injury, which signaling through AKT, ERK and PKC. P2Y2 could be a potential intervention target after muscle injury.