eIF4E Levels Research Articles

CDR1as/miR-7-5p/IGF1R axis contributes to the suppression of cell viability in prostate cancer

Abstract Background Prostate cancer is the most frequently diagnosed male cancer and the fifth highest cause of cancer mortality in men. CDR1as has played an essential role in the growth of several malignancies. However, its significance in the progression of prostate cancer has not been investigated. We aimed to investigate the role and mechanism of CDR1as in the development of prostate cancer and identify a new target for diagnostics and treatment. Methods CDR1as siRNA and miR-7-5p mimic were transfected into PC3 and DU145 PCa cell lines and their effects on cellular processes were investigated. Cell viability was measured by WST-8 assay. The role of CDR1as and/or miR-7-5p on PCa cell migration was detected using the scratch-wound assay. The apoptotic capacity of the cells was evaluated using the Caspase-3 kit. The potential targets of miR-7-5p were defined via in silico tools. mRNA and protein expression levels of IGF1R and EIF4E were detected by qRT-PCR and western blot assays, respectively. The matching between miR-7-5p and IGF1R was defined via luciferase reporter assay. Results Inhibiting CDR1as or restoring miR-7-5p reduced prostate cancer cell proliferation and migration while increasing apoptosis. Silencing CDR1as elevated the expression of miR-7-5p while decreasing IGF1R. Conclusions CDR1as functions as a miR-7-5p sponge, increasing IGF1R expression and promoting tumor development.

Abstract 2400: Determinants of early recurrence in surgically-resected colon cancer: A multi-omics analysis

Abstract Introduction: Colon cancer is the third most common cancer worldwide. The mainstay treatment for localized disease is surgical resection, often followed by adjuvant chemotherapy in stage III patients, and stage II patients with high-risk features. Unfortunately, some patients experience early local and/or distant recurrence. Besides classic anatomical/pathological tumor features, insight into the genomic determinants of early recurrence in colon cancer is lacking. Herein, we utilize a multi-omics approach to identify early-recurrence-specific features that could aid in more accurate risk stratification. Methods: We utilized the Cancer Genomic Atlas Colon Adenocarcinoma (TCGA-COAD) Database. Clinical, histopathological and genomic data were retrieved through the cBioPortal database. Our analysis was limited to patients with stage 2 or 3 (n = 390) disease based on the American Joint Committee on Cancer Code. Early recurrence (ER) was defined as disease relapse/recurrence within 12 months of sample acquisition post-surgery. Accordingly, patients were categorized into the ER and non-early recurrence (NER) groups based on a cut-off point of 12 months of disease-free survival. Results: The colon cancer ER and NER group included 45 and 345 patients, respectively. Comparable age, sex and race percentages were found between both groups. The ER group had significantly worse overall, progression-free, and disease-specific survival (HR: 0.083 95% CI: 0.031-0.220, HR: 0.035 95% CI: 0.011-0.0109, HR: 0.021 95% CI: 0.006-0.076, respectively). ER patients had a significantly higher proportion of patients with T4 and N2 disease based on the TNM staging system. ER patients had significant (P< 0.05) expression of TRIM46, TRPC4, ELOVL7, CSMD1, BCLAF1, and CD70 mutations, while tumor mutational burden was comparable between both groups (median TMB in ER vs NER: 4.2 vs 3.62, p = 0.28). Differential gene expression analysis revealed 68 genes to be upregulated in the ER group which were found to be enriched in hypoxia and interleukin-11 pathway genes. Genes upregulated in the NER group (n = 49) were enriched in interferon-alpha response and glycolysis/gluconeogenesis pathway genes. Proteomics analysis revealed significantly higher levels of EIF4E, CCNE1, SRSF1, SCD, and PECAM1 proteins in NER patients .Conclusion: Our results highlight insights into molecular and genomic features unique to colon cancer patients with early recurrence. Understanding such predictors for early recurrence will aid in risk stratification and help in determining patients who would derive the most benefit from adjuvant treatment considerations. Citation Format: Salma Al-Aomar, Hassan Abushukair, Alaa Zaitoun, Sara Zytoon, Sara Illeyyan, Husam Almomani, Ghayda'a Al-Majali, Arafat Hammad, Khaled Obeidat, Fuad Turfah, Awni Shahait, Fadwa Ali. Determinants of early recurrence in surgically-resected colon cancer: A multi-omics analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2400.

Dual targeting of Mcl-1 and Bcl-2 to overcome chemoresistance in cervical and colon cancer.

After an initial positive response to chemotherapy, cancer patients often become resistant and experience relapse. Our previous research identified eukaryotic translation initiation factor 4E (eIF4E) as a crucial target to overcome chemoresistance. In this study, we delved further into the role and therapeutic potential of myeloid cell leukemia 1 (Mcl-1), an eIF4E-mediated target, in chemoresistance. We showed that the levels of phosphor and total eIF4E, as well as Mcl-1, were elevated in chemoresistant cervical but not colon cancer cells. Mcl-1 inhibitor S64315 decreased Mcl-1 levels in chemoresistant cancer cells, regardless of Mcl-1 upregulation, decreased viability in chemoresistant cancer cells and acted synergistically with chemotherapy drugs. The combined inhibition of Mcl-1 and B-cell lymphoma 2 (Bcl-2), employing both genetic and pharmacological approaches, led to a markedly more substantial decrease in viability compared with the inhibition of either target individually. The combination of S64315 and Bcl-2 inhibitors reduced tumor growth in chemoresistant cervical and colon cancer models without causing general toxicity in mice. This combination also prolonged overall survival compared with using S64315 or venetoclax alone. Our research highlights the therapeutic potential of inhibiting Mcl-1 and Bcl-2 simultaneously in chemoresistant cancers and provides a rationale for initiating clinical trials to investigate the combination of S64315 and venetoclax for the treatment of advanced colon and cervical cancer.

The causal effect of mTORC1-dependent circulating protein levels on nonalcoholic fatty liver disease: A Mendelian randomization study

BackgroundThe mechanistic target of rapamycin (mTOR) signal pathway plays a crucial role in the development of nonalcoholic fatty liver disease (NAFLD). However, the causal effect of mTOR downstream proteins on NAFLD remains unknown. AimsWe conducted a two-sample Mendelian randomization (MR) study to investigate whether the mTOR-dependent circulating proteins, including Eukaryotic Initiation Factor 4E Binding Proteins (eIF4EBPs), Ribosomal Protein S6K kinase 1 (RP-S6K), Eukaryotic Initiation Factor 4E (eIF4E), Eukaryotic Initiation Factor 4A (eIF4A) and Eukaryotic Initiation Factor 4 G (eIF4G), have causal effects on the risk of NAFLD. MethodsThe causal estimate was evaluated with the inverse-variance weighted (IVW) method in discovery stage and validation stage. The single-nucleotide polymorphisms (SNPs) were selected to genetically predict exposures from Genome-Wide Association Studies (GWAS). Exposures with statistically significant effects in the discovery dataset would be further validated in the validation dataset. ResultsMR study revealed that eIF4E had a causal effect on NAFLD in both discovery stage (OR = 1.339, P = 0.037) and validation stage (OR = 1.0007, P = 0.022). Sensitivity analyses confirmed robustness of the results. ConclusionThe genetically predicted higher level of mTOR-dependent eIF4E in plasma might have a causal effect on the occurrence of NAFLD.

Inhibition of Eukaryotic Initiating Factor eIF4E Overcomes Abemaciclib Resistance in Gastric Cancer.

Aberrant activating mutations in cyclin-dependent kinases 4 and 6 (CDK4/6) are common in various cancers, including gastroesophageal malignancies. Although CDK4/6 inhibitors, such as abemaciclib and palbociclib, have been approved for breast cancer treatment, their effectiveness as a monotherapy remains limited for gastroesophageal tumors. The present study explored the underlying mechanism of abemaciclib resistance. Abemaciclib-resistant gastric cancer cell lines were generated, and the phospho-eukaryotic translation initiation factor 4E (p-eIF4E) and eIF4E expression was compared between resistant and parental cell lines. In order to analyze the role of eIF4E in cell resistance, siRNA knockdown was employed. The effectiveness of ribavirin alone and its combination with abemaciclib was evaluated in the gastric cancer xenograft mouse model. The upregulation of eIF4E was a common feature in gastric cancer cells exposed to prolonged abemaciclib treatment. Gastric cancer cells with increased eIF4E levels exhibited a better response to eIF4E inhibition, especially those that were resistant to abemaciclib. Ribavirin, which is an approved anti-viral drug, significantly improved the efficacy of abemaciclib, both in vitro and in vivo, by inhibiting eIF4E. Importantly, ribavirin effectively suppressed the abemaciclib-resistant gastric cancer growth in mice without causing toxicity. These findings suggest that targeting eIF4E can enhance the abemaciclib treatment for gastric cancer, proposing the potential combination therapy of CDK4/6 inhibitors with ribavirin for advanced gastric cancer.

Causal Association Between mTOR-Dependent Protein Levels and Alzheimer's Disease: A Mendelian Randomization Study.

Most previous studies supported that the mammalian target of rapamycin (mTOR) is over-activated in Alzheimer's disease (AD) and exacerbates the development of AD. It is unclear whether the causal associations between the mTOR signaling-related protein and the risk for AD exist. This study aims to investigate the causal effects of the mTOR signaling targets on AD. We explored whether the risk of AD varied with genetically predicted AKT, RP-S6K, EIF4E-BP, eIF4E, eIF4A, and eIF4G circulating levels using a two-sample Mendelian randomization analysis. The summary data for targets of the mTOR signaling were acquired from published genome-wide association studies for the INTERVAL study. Genetic associations with AD were retrieved from the International Genomics of Alzheimer's Project. We utilized the inverse variance weighted as the primary approach to calculate the effect estimates. The elevated levels of AKT (OR = 0.910, 95% CI=0.840-0.986, p = 0.02) and RP-S6K (OR = 0.910, 95% CI=0.840-0.986, p = 0.02) may decrease the AD risk. In contrast, the elevated eIF4E levels (OR = 1.805, 95% CI=1.002-1.174, p = 0.045) may genetically increase the AD risk. No statistical significance was identified for levels of EIF4-BP, eIF4A, and eIF4G with AD risk (p > 0.05). There was a causal relationship between the mTOR signaling and the risk for AD. Activating AKT and RP-S6K, or inhibiting eIF4E may be potentially beneficial to the prevention and treatment of AD.

RIP3/MLKL regulates necroptosis via activating 4EBP1-eIF4E pathway.

Necroptosis is a cell death type mediated by receptor interacting protein 3 (RIP3)/mixed lineage kinase domain-like protein (MLKL). It has been reported that mammalian target of rapamycin plays a regulatory role in necroptosis. Eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1)-eukaryotic initiation factor 4E (eIF4E) pathway is a key down streamer of mammalian target of rapamycin. However, whether 4EBP1-eIF4E pathway is involved in necroptosis is still unknown. This study aims to investigate the changes of 4EBP1-eIF4E pathway in necroptosis. TNF-α/SM-164/Z-VAD-FMK (TSZ), a necroptosis inducer, was used to induce necroptosis in murine fibroblastoid cell line L929. Cell necrosis was observed under an optical microscope. Then, TSZ was added to L929 cells with RIP3 and MLKL gene knockout. Propidium iodide (PI) staining was used to observe cell necrosis. Real-time fluorescence quantitative PCR and Western blotting were used to determine the mRNA and protein expression of 4EBP1 and eIF4E, respectively. After treating L929 cells with TSZ, the number of necrotic cells was increased, the mRNA and protein expression levels of 4EBP1 were significantly downregulated, and the ratio of phosphorylated 4EBP1 (p-4EBP1) to 4EBP1 was increased (P<0.05 or P<0.01); the mRNA expression level of eIF4E was significantly upregulated, and the ratio of phosphorylated eIF4E (p-eIF4E) to eIF4E was increased (both P<0.01). After knocking out RIP3 and MLKL in L929 cells, PI positive necrotic cells were significantly reduced, the mRNA and protein expression levels of 4EBP1 were significantly upregulated, and the ratio of p-4EBP1 to 4EBP1 was decreased (P<0.05 or P<0.01); the mRNA expression level of eIF4E was significantly downregulated, and the ratio of p-eIF4E to eIF4E was decreased (both P<0.01). 4EBP1-eIF4E pathway is activated in the RIP3/MLKL mediated-necroptosis.

Dual targeting of protein translation and nuclear protein export results in enhanced antimyeloma effects.

Selinexor (KPT-330) is a small molecule inhibitor of XPO1, which mediates the transport of tumor suppressor proteins, oncogene messenger RNAs, and other proteins involved in governing cell growthfrom the cell nucleus to the cytoplasm. It is overexpressed in many cancer types. Because eukaryotic translation initiator factor 4E (eIF4E) plays a critical role in protein translation in cancer cells in multiple myeloma (MM), we evaluated the effectiveness of combined inhibition of protein translation and nuclear export in MM. Selinexor, an inhibitor of nuclear protein export, dose-dependently decreased eIF4E, IKZF1, and c-MYC protein levels. Using a doxycycline-inducible-pLKO-Tet-On vector, knockdown of eIF4E significantly enhanced the antiproliferative effects of selinexor, sensitized resistant MM cells to selinexor, and increased apoptosis in MM cells. Immunofluorescent analysis of MM cells showed that the combined treatment increased the localization of residual eIF4E to the nucleus compared with selinexor-only treatment. The overexpression of eIF4E at least partially rescued the effects of selinexor in MM cells by reducing G1 cell cycle arrest and increasing the selinexor-IC50 10-fold. Moreover, the combination of selinexor with pharmacologic inhibitors of protein translation showed synergistic anti-MM effects. These results suggest a synergistic anti-MM effect of selinexor combined with eIF4E inhibitors invitro. Our work provides a better understanding of the potential mechanism of resistance to selinexor and a rationale for combining selinexor with eIF4E inhibitors for the treatment of MM.

EIF3D promotes resistance to 5-fluorouracil in colorectal cancer through upregulating RUVBL1.

As EIF3D is oncogenic in colorectal cancer (CRC) and is associated with multidrug resistance, this study aims to investigate whether and how EIF3D regulates resistance to 5-fluorouracil (5-Fu) in CRC. EIF3D-associated genes in CRC were predicted using bioinformatics tools. CRC cells and nude mice received 5-Fu treatment. Then, the impacts of EIF3D and the interaction between EIF3D and RUVBL1 on cell viability, colony formation, apoptosis, and DNA damage were detected through MTT, colony formation, flow cytometry, and immunofluorescence assays, and those on in vivo tumorigenesis through murine xenograft assay. IC50 value of 5-Fu for CRC cells was determined by probit regression analysis. Expressions of EIF3D, eIF4E, EIF3D-associated genes, γH2AX, Bcl-2, Bax, and Cleaved Caspase-3/Caspase-3 in CRC tissues, cells, and/or xenograft tumors were analyzed by qRT-PCR and/or Western blot. EIF3D and RUVBL1 were highly expressed and positively correlated with CRC tissues/cells. In CRC cells, except for eIF4E, both EIF3D and RUVBL1 levels were upregulated by 5-Fu treatment; in addition to that, RUVBL1 level was downregulated by EIF3D silencing rather than eIF4E. Meanwhile, EIF3D silencing diminished IC50 value of 5-Fu and potentiated 5-Fu-induced viability decrease, colony formation inhibition, apoptosis promotion, Bcl-2 downregulation, and γH2AX, Bax, and Cleaved Caspase-3/Caspase-3 upregulation but reversed 5-Fu-triggered RUVBL1 upregulation. RUVBL1 overexpression offsets EIF3D silencing-induced viability decrease and apoptosis promotion of 5-Fu-treated CRC cells, and tumorigenesis suppression and apoptosis promotion in 5-Fu-treated mice. EIF3D promotes resistance to 5-Fu in CRC through upregulating RUVBL1 level.

Effect of dietary poly-γ-glutamic acid on growth, digestive enzyme activity, antioxidant capacity, and TOR pathway gene expression of gibel carp (Carassius auratus gibelio)

This study evaluated the effects of poly-γ-glutamic acid (γ-PGA) diets on the growth, antioxidant capacity, and nutrient absorption of gibel carp. Six groups (Control, PGA-25, PGA-50, PGA-100, PGA-200 and PGA −400) were supplemented with different γ-PGA addition (0, 25, 50, 100, 200, 400 mg/kg), respectively, and were fed for 8 weeks. The results showed that the final weight (FW), weight gain (WG) were quadratically and cubically increased (P < 0.05) with increasing dietary γ-PGA levels. The specific growth rate (SGR) was quadratically and cubically decreased (P < 0.05) with increasing dietary γ-PGA levels. The back muscle moisture, crude protein and fat were not significantly affected (P > 0.05), whereas the crude fat was cubically affected by graded dietary γ-PGA levels (P = 0.049). The serum albumin (ALB) content was cubically increased, whereas the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, triglyceride (TG) and total cholesterol (TC) were decreased with increasing dietary γ-PGA levels. The alkaline phosphatase (ALP) activity, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), however, were not affected by the γ-PGA trail. Digestive enzymes, including amylase, lipase and trypsin in the intestine and liver, were all quadratically or cubically increased with increasing dietary γ-PGA levels (P < 0.05). The increasing γ-PGA levels significantly affected total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and catalase (CAT) activities, and content of malondialdehyde (MDA) and glutathione (GSH). Real-time quantitative PCR (RT-qPCR) analysis revealed that the transcription levels of sod, cat, gsta genes in group PGA-100 were significantly increased by 39.0 %, 59.2 % and 51.6 % compared with group Control, respectively. Meanwhile, the group PGA-100 also up-regulated the transcription levels of TOR, 4E-BP2, eIF4E and GHR. The cubic regression analysis based on FW and WG, the optimal dietary γ-PGA requirement was estimated to be 104 mg/kg for gibel carp.

Synergistic Anti-Tumor Effect on Novel Combination of Selinexor with Azacitidine in AML By Targeting XPO1/eIF4E/C-MYC Signaling

Background: Acute myeloid leukemia (AML) is a heterogeneous hematologic malignancy with high mortality and poor outcome. Highly effective therapy options are always needed for AML. Selinexor (KPT-330) is an oral bioactive selective CRM1 (XPO1) inhibitor, and the clinical trial showed the combination of KPT-330 over standard induction therapy benefits much for AML patients. Azacitidine (AZA), a DNA hypomethylation agent, can induce cell apoptosis and exhibit potential therapeutic efficacy against AML. However, it has not yet determined the anti-tumor effect of KPT-330 with AZA in AML. Here we examined the anti-leukemia effect and potential mechanism of KPT-330 combined with AZA in AML cells to provide evidence for further clinical trials. Methods: A total of 64 AML patients’ BM samples and 64 normal control from healthy volunteers were obtained from Zhongda Hospital Southeast University, in which the 2 patients’ samples were further treated with indicated drugs in vitro. Cell Counting Kit-8 (CCK-8) was used for cell viability assay, Annexin-V/PI staining following flow cytometry analysis for apoptosis, and qPCR and Western Blot for gene expression in AML cell lines and patient samples. CalcuSyn analysis was performed for a synergistic effect. RNA-seq was performed in U937 cells treated with 0.7uM AZA for 48 hrs, and the significantly differentially expressed genes (DEGs) were identified and gene set enrichment analysis (GSEA) was performed. Results: Cell proliferation arrest and apoptosis were significantly observed in U937 and MV4-11 cells treated with the combination of KPT-330 with AZA compared to single drug control (data not shown). Then, we further explored the synergistic effect of the combination in patients’ samples. Results showed that cell growth arrest and apoptosis significantly increased in primary samples from two de novo AML patients compared to the single drug controls, and CalcuSyn analysis showed a synergistic effect of the combination on cell growth arrest (Fig. 1A &1B). To understand the mechanisms underlying the synergy, RNA-seq analysis was performed in U937 cells treated by 0.7uM AZA and 4655 DEGs were identified. XPO1, eIF4E, and MYC are in the top DEGs upon AZA treatment, and GSEA analysis indicated MYC_TARGETS and apoptosis pathway are enriched in DEGs (Fig. 1C &1D ). Moreover, the mRNA level of XPO1 and eIF4E was increased in our AML patient cohort compared with healthy controls (Fig. 1E), and the high expression of XPO1 or elF4E are associated with poor outcome (Fig. 1F). XPO1 is the key component of nuclear-exporting machinery; elF4E, the cargo of XPO1 is translation initiation factor and plays a critical role in translational machinery, which regulates the C-MYC translation. It is also reported that AZA regulates the transcription of C-MYC by affecting methylation. We observed a combination of KPT-330 with AZA significantly down-regulated the mRNA and protein level of oncogene eIF4E and C-MYC in two of the patients’ samples compared to single drug controls (Fig. 1G &1H ). Also, C-MYC knock-down was not only significantly increased the apoptosis in U937 cells compared to scramble shRNA (shCTL) control, but also significantly enhanced the combination-mediated apoptosis compared to that of single drug control in U937 cells (Fig. 1I). these data indicated that XPO1/eIF4E/C-MYC signaling plays critical roles in the combination-mediated anti-leukemia, and the mechanistic model is summarized in Fig.1J. Conclusions: Our data for the first time showed the synergistic effect of a novel combination of KPT-330 with AZA on cell growth arrest and apoptosis in AML patients and also identified the underlying mechanism by targeting XPO1/eIF4E/C-MYC signaling. Our results also highlighted the feasibility of the clinical trial for the combination in the therapy of AML patients. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Translational regulation of TFH cell differentiation and autoimmune pathogenesis.

Little is known regarding T cell translational regulation. We demonstrate that T follicular helper (TFH) cells use a previously unknown mechanism of selective messenger RNA (mRNA) translation for their differentiation, role in B cell maturation, and in autoimmune pathogenesis. We show that TFH cells have much higher levels of translation factor eIF4E than non-TFH CD4+ T cells, which is essential for translation of TFH cell fate-specification mRNAs. Genome-wide translation studies indicate that modest down-regulation of eIF4E activity by a small-molecule inhibitor or short hairpin RN impairs TFH cell development and function. In mice, down-regulation of eIF4E activity specifically reduces TFH cells among T helper subtypes, germinal centers, B cell recruitment, and antibody production. In experimental autoimmune encephalomyelitis, eIF4E activity down-regulation blocks TFH cell participation in disease pathogenesis while promoting rapid remission and spinal cord remyelination. TFH cell development and its role in autoimmune pathogenesis involve selective mRNA translation that is highly druggable.

Replacement of dietary fish meal by soybean meal on growth performance, immunity, anti-oxidative capacity and mTOR pathways in juvenile abalone Haliotis discus hannai Ino

This study aimed to evaluate the effects of replacing fish meal with soybean meal (SBM) on growth performance, immunity, anti-oxidative capacity and mTOR pathway in juvenile abalone Haliotis discus hannai Ino. Five isonitrogenous (about 29% of crude protein) and isolipidic (about 4% of crude lipid) experimental diets with graded levels of fish meal replaced by SBM (0, 25, 50, 75 and 100%, respectively) were fed to abalone (initial body weight: 21.87 ± 0.07 g, initial shell length: 53.18 ± 0.18 mm) for 16 weeks. These experimental diets were named as SBM0, SBM25, SBM50, SBM75 and SBM100, respectively. The results showed that: 1) There was no significant difference in survival of abalone among all the treatments. The highest weight gain rate was found in the SBM50 group, and the group did not significantly differ from those in the SBM75 and SBM100 groups. 2) Replacement of fish meal by SBM linearly and quadratically increased the crude lipid content in muscle of abalone, which reached its highest level in the SBM50 group. 3) Trypsin activity in the digestive gland of abalone fed SBM25 diet was significantly higher than that of other groups. 4) The highest total anti-oxidative capacity and superoxidase activity in digestive gland were found in the SBM50 group. 5) The highest mRNA levels of pi3k and eif-4e, and the lowest level of 4e-bp in muscle were found in the SBM50 group. There was no significant difference in the mRNA level of mtor in the muscle among all the groups. 6). The lowest expression level of nf-κb and the highest expression level of mytimacin 6 in digestive gland of abalone were observed fed SBM50 diet. A significant quadratic trend was found in the mRNA levels of il-16 with increasing levels of dietary SBM. Meanwhile, the mRNA level of β-defensin was linearly decreased after total replacement of fish meal by SBM. Take the growth, antioxidation, immune and mTOR pathway into account, 50% replacement of dietary fish meal by SBM was recommended for abalone.

Ribavirin inhibits the growth and ascites formation of hepatocellular carcinoma through downregulation of type I CARM1 and type II PRMT5

Type I co-activator-associated arginine methyltransferase 1 (CARM1) and type II protein arginine methyltransferase 5 (PRMT5) are highly expressed in multiple cancers including liver cancer and their overexpression contributes to poor prognosis, thus making them promising therapeutic targets. Here, we evaluated anti-tumor activity of ribavirin in hepatocellular carcinoma (HCC). We found that ribavirin significantly inhibited the proliferation of HCC cells in a time- and dose-dependent manner. Furthermore, ribavirin suppressed the growth of subcutaneous and orthotopic xenograft of HCC in mice, decreased vascular endothelial growth factor (VEGF) and peritoneal permeability to reduce ascites production, and prolonged the survival of mice in HCC ascites tumor models. Mechanistically, ribavirin potently down-regulated global protein expression of CARM1 and PRMT5, and concurrently decreased accumulation of H3R17me2a and H3R8me2s/H4R3me2s. However, ribavirin did not affect the activity and mRNA levels of both CARM1 and PRMT5 in vivo and in vitro HCC cells. In addition, our ChIP results shown that ribavirin inhibited CARM1 which in turn decreased the H3R17me2a, binds to the eukaryotic translation initiation factor 4E (eIF4E) and VEGF promoter region, and reduced the relative mRNA expression level of eIF4E and VEGF in HCC cells. Our findings suggested a potential therapeutic strategy for patients with HCC through inhibition of the abnormal activation/expression of both CARM1 and PRMT5.

Role of Borneol Induced Autophagy in Enhancing Radiosensitivity of Malignant Glioma.

Glioma is the common primary craniocerebral malignancy with unfavorable prognosis. It is currently treated by surgical resection supplemented by radiotherapy, although the resistance of glioma cells to radiation limits the therapeutic outcomes. The aim of the present study was to determine the potential radiosensitizing effects of borneol and the underlying mechanisms. We found that borneol administration along with radiotherapy significantly inhibited the growth of primary glioma cells in vitro and in vivo. Furthermore, borneol markedly increased the number of autophagosomes in the glioma cells, which coincided with increased expression of beclin-1 and LC3. And the combination of borneol and radiation exposure significantly decreased the expression levels of HIF-1α, mTORC1 and eIF4E. In addition, silencing mTORC1 and eIF4E upregulated Beclin-1 and LC3 and decreased the expression of HIF-1α, thereby inhibiting tumor cell proliferation. Our findings suggest that borneol sensitizes glioma cells to radiation by inducing autophagy via inhibition of the mTORC1/eIF4E/HIF-1α regulatory axis.

Treadmill running prevents atrophy differently in fast- versus slow-twitch muscles in a rat model of rheumatoid arthritis.

To investigate the effects of treadmill running on two different types of skeletal muscle, we established a rat model of collagen-induced arthritis (CIA). The skeletal muscles studied were the extensor digitorum longus (EDL), which is rich in fast-twitch muscle fibers, and the soleus, which is rich in slow-twitch muscle fibers. The histological and transcriptional changes in these muscles at 14 and 44days after immunosensitization were compared between rats that were forced to exercise (CIA ex group) and free-reared CIA rats (CIA no group). Change in protein expression was examined on day 14 after a single bout of treadmill running. Treadmill running had different effects on the relative muscle weight and total and fiber cross-sectional areas in each muscle type. In the soleus, it prevented muscle atrophy. Transcriptional analysis revealed increased eukaryotic translation initiation factor 4E (Eif4e) expression on day 14 and increased Atrogin-1 and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) expression on day 44 in the soleus in the CIA ex group, suggesting an interaction between muscle type and exercise. A single bout of treadmill running increased the level of Eif4e and p70S6K and decreased that of Atrogin-1 in the soleus on day 14. Treadmill running prevented muscle atrophy in the soleus in a rat model of rheumatoid arthritis via activation of mitochondrial function, as evidenced by increased PGC-1α expression.

Arginine Regulates TOR Signaling Pathway through SLC38A9 in Abalone Haliotis discus hannai.

Arginine plays an important role in the regulation of the target of the rapamycin (TOR) signaling pathway, and Solute Carrier Family 38 Member 9 (SLC38A9) was identified to participate in the amino acid-dependent activation of TOR in humans. However, the regulations of arginine on the TOR signaling pathway in abalone are still unclear. In this study, slc38a9 of abalone was cloned, and the slc38a9 was knocked down and overexpressed to explore its function in the regulation of the TOR signaling pathway. The results showed that knockdown of slc38a9 decreased the expression of tor, ribosomal s6 protein kinase (s6k) and eukaryotic translation initiation factor 4e (eif4e) and inhibited the activation of the TOR signaling pathway by arginine. Overexpression of slc38a9 up-regulated the expression of TOR-related genes. In addition, hemocytes of abalone were treated with 0, 0.2, 0.5, 1, 2 and 4 mmol/L of arginine, and abalones were fed diets with 1.17%, 1.68% and 3.43% of arginine, respectively, for 120 days. Supplementation of arginine (0.5–4 mmol/L) increased the expressions of slc38a9, tor, s6k and eif4e in hemocytes, and abalone fed with 1.68% of dietary arginine showed higher mRNA levels of slc38a9, tor, s6k and eif4e and phosphorylation levels of TOR, S6 and 4E-BP. In conclusion, the TOR signaling pathway of abalone can be regulated by arginine, and SLC38A9 plays an essential role in this regulation.

Assessing eukaryotic initiation factor 4F subunit essentiality by CRISPR-induced gene ablation in the mouse.

Eukaryotic initiation factor (eIF) 4F plays a central role in the ribosome recruitment phase of cap-dependent translation. This heterotrimeric complex consists of a cap binding subunit (eIF4E), a DEAD-box RNA helicase (eIF4A), and a large bridging protein (eIF4G). In mammalian cells, there are two genes encoding eIF4A (eIF4A1 and eIF4A2) and eIF4G (eIF4G1 and eIF4G3) paralogs that can assemble into eIF4F complexes. To query the essential nature of the eIF4F subunits in normal development, we used CRISPR/Cas9 to generate mouse strains with targeted ablation of each gene encoding the different eIF4F subunits. We find that Eif4e, Eif4g1, and Eif4a1 are essential for viability in the mouse, whereas Eif4g3 and Eif4a2 are not. However, Eif4g3 and Eif4a2 do play essential roles in spermatogenesis. Crossing of these strains to the lymphoma-prone Eμ-Myc mouse model revealed that heterozygosity at the Eif4e or Eif4a1 loci significantly delayed tumor onset. Lastly, tumors derived from Eif4e∆38fs/+/Eμ-Myc or Eif4a1∆5fs/+/Eμ-Myc mice show increased sensitivity to the chemotherapeutic agent doxorubicin, in vivo. Our study reveals that eIF4A2 and eIF4G3 play non-essential roles in gene expression regulation during embryogenesis; whereas reductions in eIF4E or eIF4A1 levels are protective against tumor development in a murine Myc-driven lymphoma setting.

A Maternal High-Fat Diet during Early Development Provokes Molecular Changes Related to Autism Spectrum Disorder in the Rat Offspring Brain.

Autism spectrum disorder (ASD) is a disruptive neurodevelopmental disorder manifested by abnormal social interactions, communication, emotional circuits, and repetitive behaviors and is more often diagnosed in boys than in girls. It is postulated that ASD is caused by a complex interaction between genetic and environmental factors. Epigenetics provides a mechanistic link between exposure to an unbalanced maternal diet and persistent modifications in gene expression levels that can lead to phenotype changes in the offspring. To better understand the impact of the early development environment on the risk of ASD in offspring, we assessed the effect of maternal high-fat (HFD), high-carbohydrate, and mixed diets on molecular changes in adolescent and young adult offspring frontal cortex and hippocampus. Our results showed that maternal HFD significantly altered the expression of 48 ASD-related genes in the frontal cortex of male offspring. Moreover, exposure to maternal HFD led to sex- and age-dependent changes in the protein levels of ANKRD11, EIF4E, NF1, SETD1B, SHANK1 and TAOK2, as well as differences in DNA methylation levels in the frontal cortex and hippocampus of the offspring. Taken together, it was concluded that a maternal HFD during pregnancy and lactation periods can lead to abnormal brain development within the transcription and translation of ASD-related genes mainly in male offspring.

Eukaryotic initiating factor eIF4E is targeted by EBV-encoded miR-BART11-3p and regulates cell cycle and apoptosis in EBV-associated gastric carcinoma.

The eukaryotic translation initiation factor 4E (eIF4E) is a component of the eukaryotic translation initiation factor 4F, a significant complex in the protein translation process. It has been found to be closely related to many human tumors, such as gastric carcinoma. It is known that the Epstein-Barr virus (EBV) upregulates eIF4E in various ways in nasopharyngeal carcinoma. However, there are very few studies on eIF4E in EBV-associated gastric carcinoma. We found that the expression level of eIF4E in EBV-associated gastric carcinoma was lower than other types of gastric carcinoma, and the downregulation of eIF4E could lead to increased apoptosis of gastric carcinoma cells, retardation at S phase, and decreased cell migration. The dual luciferase reporter experiment showed that EBV-miR-BART11-3p could directly target the 3'-UTR region of eIF4E, and BART11-3p is the key factor leading to the downregulation of eIF4E. It could provide a new evidence for EBV-regulating host gene to affect the development of gastric carcinoma.