Downregulation of eukaryotic translation initiation factor 3b inhibited proliferation and metastasis of gastric cancer

EIF3B affects the invasion and metastasis of hepatocellular carcinoma cells via the TGFBI/MAPK/ERK pathway

INTRODUCTION AND OBJECTIVES

To study the effect of eukaryotic initiation factor 3B (EIF3B) on the invasion and migration of hepatocellular carcinoma (HCC) and its potential mechanism.

MATERIALS AND METHODS

The clinical significance of EIF3B expression was studied with The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interaction Analysis datasets. Immunohistochemical staining and western blotting were used to examine EIF3B expression in cell lines and tissues from HCC patients. The scratch assay and transwell assay were used to measure the invasion and metastasis of different HCC cell lines in vitro. The molecular mechanism of EIF3B was determined using RNA-seq and identification of dysregulated signaling pathways. Western blotting was used to verify the alterations of EIF3B signaling functioned in the promotion of HCC progression.

RESULTS

Elevated expression of EIF3B in HCC correlated significantly with aggressive clinicopathologic characteristics, including advanced tumor grade and poor prognosis. Studies with cultured cells indicated that EIF3B knockdown inhibited HCC cell invasion and metastasis by depressing the epithelial-mesenchymal transition (EMT). EIF3B also activated the TGFBI/MAPK/ERK signaling pathway by increasing the levels of pMEK and pERK.

CONCLUSIONS

Our results indicate that EIF3B functions as an oncogene in HCC that accelerates cell invasion, metastasis, and the EMT by stimulation of the TGFBI/MAPK/ERK signaling pathway. EIF3B is a potential target for the treatment of HCC.

FOXA1-dependent PUS1 regulates EIF3b stability in a non-enzymatic pathway mediating prostate cancer bone metastasis

Bone metastasis is a significant contributor to the poor prognosis in prostate cancer. Recent evidence highlights the pivotal role of pseudouridine synthases in solid tumor progression, yet the specific enzyme driving prostate cancer metastasis remains unidentified. This study uncovers a novel regulatory mechanism of the FOXA1/PUS1/EIF3b signaling axis in prostate cancer bone metastasis. We identified elevated PUS1 expression in prostate cancer tissues, correlating with higher clinical grade and worse prognosis. Knockdown of PUS1 inhibited metastasis independently of its enzymatic activity, with EIF3b acting as a downstream effector, protected from ubiquitin-mediated degradation by PUS1. Overexpression of EIF3b countered the metastasis suppression due to PUS1 knockdown. Additionally, FOXA1 was shown to enhance PUS1 expression by binding to its promoter. Mogroside IV-E, a specific PUS1 inhibitor, demonstrated potent anti-metastatic effects by reducing PUS1 expression. Our findings highlight the FOXA1/PUS1/EIF3b axis as a critical mediator of prostate cancer bone metastasis and suggest that targeting this pathway could be a promising therapeutic strategy.

N6-methyladenosine modification of hypoxia-inducible factor-1α regulates Helicobacter pylori-associated gastric cancer via the PI3K/AKT pathway

BACKGROUND

Helicobacter pylori (H. pylori) colonizes the human gastric mucosa and is implicated in the development of gastric cancer (GC). The tumor microenvironment is characterized by hypoxia, where hypoxia-inducible factor-1α (HIF-1α) plays a key role as a transcription factor, but the mechanisms underlying H. pylori-induced HIF-1α expression and carcinogenesis remain unclear.

AIM

To explore the underlying mechanism of H. pylori-induced HIF-1α expression in promoting the malignant biological behavior of gastric epithelial cells (GES-1).

METHODS

The study was conducted with human GES-1 cells in vitro. Relative protein levels of methyltransferase-like protein 14 (METTL14), HIF-1α, main proteins of the PI3K/AKT pathway, epithelial-mesenchymal transition (EMT) biomarkers, and invasion indicators were detected by Western blot. Relative mRNA levels of METTL14 and HIF-1α were detected by quantitative reverse transcription-polymerase chain reaction. mRNA stability was evaluated using actinomycin D, and the interaction between METTL14 and HIF-1α was confirmed by immunofluorescence staining. Cell proliferation and migration were evaluated by cell counting kit-8 assay and wound healing assay, respectively.

RESULTS

H. pylori promoted HIF-1α expression and activated the PI3K/AKT pathway. Notably, METTL14 was downregulated in H. pylori-infected gastric mucosal epithelial cells and positively regulated HIF-1α expression. Functional experiments showed that the overexpression of HIF-1α or knockdown of METTL14 enhanced the activity of the PI3K/AKT pathway, thereby driving a series of malignant transformation, such as EMT and cell proliferation, migration, and invasion. By contrast, the knockdown of HIF-1α or overexpression of METTL14 had an opposite effect.

CONCLUSION

H. pylori-induced underexpression of METTL14 promotes the translation of HIF-1α and accelerates tumor progression by activating the PI3K/AKT pathway. These results provide novel insights into the carcinogenesis of GC.

Lnc-PLCB1 is stabilized by METTL14 induced m6A modification and inhibits Helicobacter pylori mediated gastric cancer by destabilizing DDX21

Helicobacter pylori (H. pylori) infection is considered to be an important factor in gastric cancer (GC). Long noncoding RNA (lncRNA) and m6A modification are involved in the occurrence and development of GC, but the role of lncRNA m6A modification in the development of GC mediated by H. pylori is still unclear. Here, we found that H. pylori infection downregulated the expression of lnc-PLCB1 through METTL14-mediated m6A modification and IRF2-mediated transcriptional regulation. Overexpression of lnc-PLCB1 inhibited the proliferation and migration of GC cells, while downregulation of lnc-PLCB1 promoted the proliferation and migration ability of GC cells. In addition, clinical analysis showed that lnc-PLCB1 is lower in GC tissues than in normal tissues. Further study found that lnc-PLCB1 reduced the protein stability of its binding protein DEAD-box helicase 21 (DDX21) and then downregulated the expression of CCND1 and Slug, thereby playing tumour suppressing role in the occurrence and development of GC. In conclusion, the METTL14/lnc-PLCB1/DDX21 axis plays an important role in H. pylori-mediated GC, and lnc-PLCB1 can be used as a new target for GC treatment.

Impact of N6-methyladenosine (m6A) modification on immunity

N6-methyl-adenosine (m⁶A) is the most prevalent modification on mRNAs and long noncoding RNAs (lnRNAs) in higher eukaryotes. Modulation of m⁶A relies on m⁶A writers, erasers and readers. m⁶A modification contributes to diverse fundamental biological functions at the molecular, cellular, and physiological levels. The dysregulation of m⁶A modification has been implicated in various human diseases. Thus, m⁶A modification has now become a research hotspot for its potential therapeutic applications in the treatment of various cancers and diseases. The immune system is essential to provide defense against infections and cancers. This review summarizes the current knowledge about the roles of m⁶A in regulating immune cell functions and immune responses.

Lockd promotes myoblast proliferation and muscle regeneration via binding with DHX36 to facilitate 5' UTR rG4 unwinding and Anp32e translation

Adult muscle stem cells, also known as satellite cells (SCs), play pivotal roles in muscle regeneration, and long non-coding RNA (lncRNA) functions in SCs remain largely unknown. Here, we identify a lncRNA, Lockd, which is induced in activated SCs upon acute muscle injury. We demonstrate that Lockd promotes SC proliferation; deletion of Lockd leads to cell-cycle arrest, and in vivo repression of Lockd in mouse muscles hinders regeneration process. Mechanistically, we show that Lockd directly interacts with RNA helicase DHX36 and the 5'end of Lockd possesses the strongest binding with DHX36. Furthermore, we demonstrate that Lockd stabilizes the interaction between DHX36 and EIF3B proteins; synergistically, this complex unwinds the RNA G-quadruplex (rG4) structure formed at Anp32e mRNA 5' UTR and promotes the translation of ANP32E protein, which is required for myoblast proliferation. Altogether, our findings identify a regulatory Lockd/DHX36/Anp32e axis that promotes myoblast proliferation and acute-injury-induced muscle regeneration.

CircMAN1A2 is upregulated by Helicobacter pylori and promotes development of gastric cancer

Helicobacter pylori (H. pylori) is one of the main causes of gastric cancer. It has been reported that circRNAs play a vital role in the development of multiple types of cancer. However, the role of H. pylori-induced circRNAs in the development of gastric cancer has not been studied. In this study, we found that H. pylori could induce the upregulation of circMAN1A2 in AGS and BGC823 cells independent of CagA. The downregulation of circMAN1A2 could inhibit the proliferation, migration and invasion of gastric cancer cells, and circMAN1A2 could promote the progression of gastric cancer induced by H. pylori by sponging miR-1236-3p to regulate MTA2 expression. Furthermore, circMAN1A2 knockdown inhibited xenograft tumour growth in vivo, and the overexpression of circMAN1A2 was associated with the progression of gastric cancer. Hence, Helicobacter pylori induced circMAN1A2 expression to promote the carcinogenesis of gastric cancer, and circMAN1A2 might be a new potential diagnostic marker and therapeutic target for gastric cancer.

Eukaryotic translation initiation factor 3 subunit B promotes head and neck cancer via CEBPB translation

Background

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer type worldwide. Deregulation of mRNA translation is a frequent feature of cancer. Eukaryotic translation initiation factor 3 subunit B (EIF3B) has been reported as an oncogene; however, its role in HNSCC has yet to be fully elucidated.

Methods

In this study, the clinical significance of EIF3B expression was analyzed based on TCGA datasets. Then, EIF3B expression was knocked down and its role in HNSCC was revealed. To explore the molecular mechanisms of EIF3B, we applied RNA sequencing and proteomics and acquired deregulated pathways. RNA immunoprecipitation (RIP) sequencing was conducted to reveal the target mRNAs of EIF3B, and TCGA datasets were used to validate potential targets of EIF3B.

Results

Elevated expression of EIF3B was observed in the HNSCC cancer samples. The expression of EIF3B was significantly correlated with the patient’s sex, age, HPV infection status, T stage, N stage, perineural invasion status and survival status. EIF3B serves as a marker of an unfavorable HNSCC prognosis. EIF3B-silenced Fadu and Cal27 cells exhibited reduced cell numbers, and EIF3B knockdown induced apoptosis in both cell lines. The EIF3B-silenced cells demonstrated decreased invasion and migration capabilities, and the EIF3B knockdown group mice showed significantly decreased tumor volumes. The results show that EIF3B promotes CEBPB translation and activates the MAPK pathway and revealed that IL6R and CCNG2 are targets of EIF3B-regulated CEBPB translation.

Conclusion

In summary, the results indicated that EIF3B is a novel oncogene in HNSCC that promotes CEBPB translation and IL6R expression, and these findings provide a link between the molecular basis and pathogenesis of HNSCC.

Graphical Abstract

EIF3B is a prognostic biomarker for HNSCC risk;

EIF3B promotes HNSCC progression in vitro and in vivo;

EIF3B promotes CEBPB translation and activates the MAPK pathway;

IL6R and CCNG2 are targets of EIF3B-regulated CEBPB translation.

Establishing a Prognostic Model Based on Ulceration and Immune Related Genes in Melanoma Patients and Identification of EIF3B as a Therapeutic Target

Ulceration and immune status are independent prognostic factors for survival in melanoma patients. Herein univariate Cox regression analysis revealed 53 ulcer-immunity-related DEGs. We performed consensus clustering to divide The Cancer Genome Atlas (TCGA) cohort (n = 467) into three subtypes with different prognosis and biological functions, followed by validation in three merged Gene Expression Omnibus (GEO) cohorts (n = 399). Multiomics approach was used to assess differences among the subtypes. Cluster 3 showed relatively lesser amplification and expression of immune checkpoint genes. Moreover, Cluster 3 lacked immune-related pathways and immune cell infiltration, and had higher proportion of non-responders to immunotherapy. We also constructed a prognostic model based on ulceration and immune related genes in melanoma. EIF3B was a hub gene in the intersection between genes specific to Cluster 3 and those pivotal for melanoma growth (DepMap, https://depmap.org/portal/download/). High EIF3B expression in TCGA and GEO datasets was related to worst prognosis. In vitro models revealed that EIF3B knockdown inhibited melanoma cell migration and invasion, and decreased TGF-β1 level in supernatant compared with si-NC cells. EIF3B expression was negatively correlated with immune-related signaling pathways, immune cell gene signatures, and immune checkpoint gene expression. Moreover, its low expression could predict partial response to anti-PD-1 immunotherapy. To summarize, we established a prognostic model for melanoma and identified the role of EIF3B in melanoma progression and immunotherapy resistance development.

Eukaryotic translation initiation factor 3 subunit B could serve as a potential prognostic predictor for breast cancer

The EIF3 gene family is essential in controlling translation initiation during the cell cycle. The significance of the EIF3 subunits as prognostic markers and therapeutic targets in breast cancer is not yet clear. We analyzed the expression of EIF3 subunits in breast cancer on the GEPIA and Oncomine databases and compared their expression in breast cancer and normal tissues using BRCA data downloaded from TCGA. Then we performed clinical survival analysis on the Kaplan–Meier Plotter database and clinicopathologic analysis on the bc-genexMiner v4.1 database. And EIF3B was chosen for mutation analysis via the Cancer SEA online tool. Meanwhile, we performed the immunohistochemical assay, real-time RT-PCR, and Western blotting to analyze EIF3B expression levels in breast cancer. An EIF3B knockdown and a negative control cell line were conducted for MTT assay and cell cycle analysis to assess cell growth. Specifically, the results of TCGA and online databases demonstrated that upregulated EIF3B was associated with poorer overall and advanced tumor progression. We also confirmed that EIF3B was more highly expressed in breast cancer cells and tissues than normal and correlated with a worse outcome. And knockdown of EIF3B expression inhibited the cell cycle and proliferation. Furthermore, EIF3B was highly mutated in breast cancer. Collectively, our results suggested EIF3B as a potential prognostic marker and therapeutic target for breast cancer.

Downregulation of Methionine Cycle Genes MAT1A and GNMT Enriches Protein-Associated Translation Process and Worsens Hepatocellular Carcinoma Prognosis

The major biological methyl donor, S-adenosylmethionine (adoMet) synthesis occurs mainly in the liver. Methionine adenosyltransferase 1A (MAT1A) and glycine N-methyltransferase (GNMT) are two key enzymes involved in the functional implications of that variation. We collected 42 RNA-seq data from paired hepatocellular carcinoma (HCC) and its adjacent normal liver tissue from the Cancer Genome Atlas (TCGA). There was no mutation found in MAT1A or GNMT RNA in the 42 HCC patients. The 11,799 genes were annotated in the RNA-Seq data, and their expression levels were used to investigate the phenotypes of low MAT1A and low GNMT by Gene Set Enrichment Analysis (GSEA). The REACTOME_TRANSLATION gene set was enriched and visualized in a heatmap along with corresponding differences in gene expression between low MAT1A versus high MAT1A and low GNMT versus high GNMT. We identified 43 genes of the REACTOME_TRANSLATION gene set that are powerful prognosis factors in HCC. The significantly predicted genes were referred into eukaryotic translation initiation (EIF3B, EIF3K), eukaryotic translation elongation (EEF1D), and ribosomal proteins (RPs). Cell models expressing various MAT1A and GNMT proved that simultaneous restoring the expression of MAT1A and GNMT decreased cell proliferation, invasion, as well as the REACTOME_TRANSLATION gene EEF1D, consistent with a better prognosis in human HCC. We demonstrated new findings that downregulation or defect in MAT1A and GNMT genes can enrich the protein-associated translation process that may account for poor HCC prognosis. This is the first study demonstrated that MAT1A and GNMT, the 2 key enzymes involved in methionine cycle, could attenuate the function of ribosome translation. We propose a potential novel mechanism by which the diminished GNMT and MAT1A expression may confer poor prognosis for HCC.

The Motility and Mesenchymal Features of Breast Cancer Cells Correlate with the Levels and Intracellular Localization of Transglutaminase Type 2

We have investigated motility in breast cancer cell lines in association with the expression of Transglutaminase type 2 (TG2) as well as upon the administration of Doxorubicin (Dox), an active cytotoxic agent that is employed in chemotherapy. The exposure of MCF-7 cells to the drug increased TG2 levels, triggering epithelial–mesenchymal transition (EMT), thereby supporting cell motility. The effects of Dox on the movement of MCF-7 cells were counteracted by treatment with NC9, a TG2 inhibitor, which induced morphological changes and also reduced the migration of MDA-MB-231 cells exhibiting high levels of TG2. The physical association of TG2 with the cytoskeletal component vimentin appeared pivotal both in drug-treated MCF-7 and in MDA-MB-231 cells and seemed to be independent of the catalytic activity of TG2. NC9 altered the subcellular distribution of TG2 and, consequently, the co-localization of TG2 with vimentin. Furthermore, NC9 induced a nuclear accumulation of TG2 as a prelude to TG2-dependent gene expression modifications. Since enzyme activity can affect both motility and nuclear functions, targeting of this protein could represent a method to improve therapeutic interventions in breast tumors, particularly those to control progression and to limit drug resistance.

Eukaryotic Translation Initiation Factor 3 Subunit B Is a Promoter in the Development and Progression of Pancreatic Cancer

Background: Pancreatic cancer (PC) is a malignant tumor with hidden incidence, high degree of malignancy, rapid disease progression, and poor prognosis. Eukaryotic translation initiation factor 3 subunit B (EIF3B) is necessary for tumor growth, which is an alternative therapeutic target for many cancers. However, little is known about the relationship between EIF3B and PC.

Methods: The expression of EIF3B in PC was detected by immunohistochemistry. EIF3B knockdown cell models were constructed by lentivirus infection. The MTT assay, the wound-healing assay, the transwell assay, the flow cytometry, and the Human Apoptosis Antibody Array was used to detect the effects of EIF3B knockdown on cell proliferation, cell migration, cell apoptosis, and cell cycle in vitro. Also, the effects of EIF3B knockdown on the tumor growth of PC were determined in vivo.

Results: This study showed that the expression level of EIF3B was significantly up-regulated in PC tumor tissues and associated with pathological grade. In vitro, EIF3B knockdown inhibited the PC cell proliferation and migration, and the apoptosis levels were obviously promoted by regulating apoptosis-related proteins including Bcl-2, HSP27, HSP60, Survivin, sTNF-R2, TNF-α, TNF-β, TRAILR-3, TRAILR-4, and XIAP. Furthermore, the tumor growth of PC was inhibited after the knockdown of EIF3B in vivo.

Conclusion: EIF3B was up-regulated in PC and was a promoter in the development and progression of PC, which could be considered as a therapeutic target for the treatment of PC.

Systematic Target Screening Revealed That Tif302 Could Be an Off-Target of the Antifungal Terbinafine in Fission Yeast

We used a heterozygous gene deletion library of fission yeasts comprising all essential and non-essential genes for a microarray screening of target genes of the antifungal terbinafine, which inhibits ergosterol synthesis via the Erg1 enzyme. We identified 14 heterozygous strains corresponding to 10 non-essential [7 ribosomal-protein (RP) coding genes, spt7, spt20, and elp2] and 4 essential genes (tif302, rpl2501, rpl31, and erg1). Expectedly, their erg1 mRNA and protein levels had decreased compared to the control strain SP286. When we studied the action mechanism of the non-essential target genes using cognate haploid deletion strains, knockout of SAGA-subunit genes caused a down-regulation in erg1 transcription compared to the control strain ED668. However, knockout of RP genes conferred no susceptibility to ergosterol-targeting antifungals. Surprisingly, the RP genes participated in the erg1 transcription as components of repressor complexes as observed in a comparison analysis of the experimental ratio of erg1 mRNA. To understand the action mechanism of the interaction between the drug and the novel essential target genes, we performed isobologram assays with terbinafine and econazole (or cycloheximide). Terbinafine susceptibility of the tif302 heterozygous strain was attributed to both decreased erg1 mRNA levels and inhibition of translation. Moreover, Tif302 was required for efficacy of both terbinafine and cycloheximide. Based on a molecular modeling analysis, terbinafine could directly bind to Tif302 in yeasts, suggesting Tif302 as a potential off-target of terbinafine. In conclusion, this genome-wide screening system can be harnessed for the identification and characterization of target genes under any condition of interest.

Hsa_circ_0026416 promotes proliferation and migration in colorectal cancer via miR-346/NFIB axis

Background

Colorectal cancer (CRC) is one of the most common cancers worldwide. Circular RNAs (circRNAs), a novel class of non-coding RNAs, have been confirmed to be key regulators of many diseases. With many scholars devoted to studying the biological function and mechanism of circRNAs, their mysterious veil is gradually being revealed. In our research, we explored a new circRNA, hsa_circ_0026416, which was identified as upregulated in CRC with the largest fold change (logFC = 3.70) of the evaluated circRNAs via analysing expression profiling data by high throughput sequencing of members of the GEO dataset (GSE77661) to explore the molecular mechanisms of CRC.

Methods

qRT-PCR and western blot analysis were utilized to assess the expression of hsa_circ_0026416, miR-346 and Nuclear Factor I/B (NFIB). CCK-8 and transwell assays were utilized to examine cell proliferation, migration and invasion in vitro, respectively. A luciferase reporter assay was used to verify the combination of hsa_circ_0026416, miR-346 and NFIB. A nude mouse xenograft model was also utilized to determine the role of hsa_circ_0026416 in CRC cell growth in vivo.

Results

Hsa_circ_0026416 was markedly upregulated in CRC patient tissues and plasma and was a poor prognosis in CRC patients. In addition, the area under the curve (AUC) of hsa_circ_0026416 (0.767) was greater than the AUC of CEA (0.670), CA19-9 (0.592) and CA72-4 (0.575). Functionally, hsa_circ_0026416 promotes cell proliferation, migration and invasion both in vitro and in vivo. Mechanistically, hsa_circ_0026416 may function as a ceRNA via competitively absorbing miR-346 to upregulate the expression of NFIB.

Conclusions

In summary, our findings demonstrate that hsa_circ_0026416 is an oncogene in CRC. Hsa_circ_0026416 promotes the progression of CRC via the miR-346/NFIB axis and may represent a potential biomarker for diagnosis and therapy in CRC.

Expression of eukaryotic translation initiation factor 3 subunit B in liver cancer and its prognostic significance

Liver cancer is one of the major malignancies with the worst prognosis among all solid tumor types. It is therefore ponderable to explore prognostic biomarkers and therapeutic targets for liver cancer. Eukaryotic translation initiation factor 3 subunit B (EIF3B) is closely linked to the transcription initiation of cancer-associated genes. In the present study, EIF3B was indicated to be a potential prognostic biomarker of liver cancer. The mRNA expression level of EIF3B in liver cancer was assessed by analyzing the Cancer Genome Atlas dataset. χ² and Fisher's exact tests were used to assess the association of EIF3B expression with clinical parameters. Receiver-operating characteristic curve analysis was used for evaluating the diagnostic value of EIF3B. Overall and relapse-free survival were assessed using Kaplan-Meier curves to determine the association between EIF3B expression and survival. Univariate and multivariate Cox regression analysis were performed to identify the factors affecting overall/relapse-free survival. Gene set enrichment analysis (GSEA) was used to identify signaling pathways associated with EIF3B in liver cancer. It was revealed that EIF3B was highly expressed in liver cancer tissues and it had a promising diagnostic ability. Furthermore, the survival analysis indicated that patients with high EIF3B expression generally had shorter overall as well as relapse-free survival. Univariate and multivariate Cox analysis suggested that high EIF3B mRNA expression may serve as an independent biomarker for the prognostication of patients with liver cancer. GSEA suggested that MYC-V1 (HALLMARK_MYC_TARGETS_V1 geneset; P=0.009), MYC-V2 (HALLMARK_MYC_TARGETS_V2 geneset; P=0.004) and DNA repair pathways (HALLMARK_DNA_REPAIR geneset; P<0.001) were differentially enriched in high EIF3B expression and low EIF3B expression groups. In conclusion, high EIF3B expression was indicated to be an independent prognostic biomarker for patients with liver cancer.

Roles of eIF3m in the tumorigenesis of triple negative breast cancer

Background

Without targets, triple negative breast cancer (TNBC) has the worst prognosis in all subtypes of breast cancer (BC). Recently, eukaryotic translation initiation factor 3 m (eIF3m) has been declared to be involved in the malignant progression of various neoplasms. The aim of this study is to explore biological functions of eIF3m in TNBC.

Methods

Multiple databases, including Oncomine, KM-plotter and so on, were performed to analyze prognosis and function of eIF3m in TNBC. After transfection of eIF3m-shRNA lentivirus, CCK-8, colony formation assay, cell cycle analysis, wound healing assay, transwell assays, mitochondrial membrane potential assay and cell apoptosis analysis were performed to explore the roles of eIF3m in TNBC cell bio-behaviors. In addition, western blotting was conducted to analyze the potential molecular mechanisms of eIF3m.

Results

In multiple databases, up-regulated eIF3m had lower overall survival, relapse-free survival and post progression survival in BC. EIF3m expression in TNBC was obviously higher than in non-TNBC or normal breast tissues. Its expression in TNBC was positively related to differentiation, lymph node invasion and distant metastasis. After knockdown of eIF3m, cell proliferation, migration, invasion and levels of mitochondrial membrane potential of MDA-MB-231 and MDA-MB-436 were all significantly suppressed, while apoptosis rates of them were obviously increased. In addition, eIF3m could regulate cell-cycle, epithelial–mesenchymal transition and apoptosis-related proteins. Combined with public databases and RT-qPCR, 14 genes were identified to be modulated by eIF3m in the development of TNBC.

Conclusions

eIF3m is an unfavorable indicator of TNBC, and plays a vital role in the process of TNBC tumorigenesis.

Identification of UAP1L1 as tumor promotor in gastric cancer through regulation of CDK6

Gastric cancer (GC) is one of the most commonly diagnosed malignancies in digestive tract and its underlying molecular mechanism is still not clear, so we aimed to reveal the relationship between GC and UDP-GlcNAc pyrophosphorylase-1 like 1 (UAP1L1). The detection of UAP1L1 expression in GC tumor and normal tissues was accomplished by immunohistochemistry and demonstrated the upregulation of UAP1L1 in GC, which was statistically associated with tumor grade. GC cell models constructed via transfection of UAP1L1-silencing/overexpressing lentiviruses were employed for evaluating the effects of UAP1L1 knockdown/overexpression on GC in vitro and in vivo. The results indicated that UAP1L1 played important role in development of GC through regulating cell proliferation, colony formation, cell apoptosis and cell migration. Subsequently, CDK6 was identified as a potential target in UAP1L1 induced regulation of GC, downregulation of which exhibited similar inhibition effects on GC with UAP1L1. Moreover, it was demonstrated that the promotion of GC by UAP1L1 overexpression could be significantly attenuated or even reversed by simultaneously silencing CDK6. In conclusion, UAP1L1 was reported to be a tumor promotor in the development and progression of GC which may exert its role through regulating CDK6 and may act as a candidate of therapeutic target in treatment.

Function and regulation annotation of up-regulated long non-coding RNA LINC01234 in gastric cancer

Background

Accumulated evidences indicate that long non‐coding RNAs (lncRNAs) participate in many biological mechanisms. Moreover, it acts as an essential regulator in various human diseases such as gastric cancer (GC). Nevertheless, the comprehensive regulatory roles and clinical significance of most lncRNAs in GC are not fully understood.

Methods

In this research, our aim was to investigate the underlying mechanism of lncRNA LINC01234 in GC. Firstly, the usage of qRT‐PCR helped to establish expression pattern of LINC01234 in GC tissues. Following this, appropriate statistical tests were applied to analyze the relation between expression level and clinicopathological factors. Ultimately, potential functions and regulatory network of LINC01234 were concluded via GSEA and a series of bioinformatics tools or databases, respectively.

Results

Consequently, at the end of research we found LINC01234 is up‐regulated in GC tissues in comparison with adjacent normal tissues. Furthermore, its expression level is correlated with differentiation of patients with GC. It is also important to highlight bioinformatics analysis revealed that LINC01234 is involved in cancer‐associated pathways such as cell cycle and mismatch repair. Also, regulatory network of LINC01234 presented a probability in the involvement of tumorigenesis through regulating cancer‐associated genes.

Conclusion

Overall, our results suggested that LINC01234 may play a crucial role in GC.