Potentiation of bortezomib's Anti-Myeloma Effects in Combination with Anti-DR5 Agonistic Antibody: The Role of ER Stress in DR5 Editing and DR-Mediated Apoptotic Signaling

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 5104-5104
Author(s):  
Hirokazu Miki ◽  
Masahiro Abe ◽  
Kumiko Kagawa ◽  
Asuka Oda ◽  
Hiroe Amou ◽  
...  
Keyword(s):  
Er Stress ◽  
Cell Lines ◽  
Critical Role ◽  
Protein Translation ◽  
Chemotherapeutic Agents ◽  
Mrna Levels ◽  
Trail Receptor ◽  
Normal Peripheral Blood ◽  
Agonistic Antibody

Abstract Abstract 5104 Bortezomib (BTZ) is widely used in the treatment of myeloma (MM) with marked response rates in both relapsed/refractory as well as newly diagnosed MM. However, significant numbers of patients still remain outside benefit of the BTZ treatment; and various combinatory treatments with BTZ have been implemented to improve BTZ's anti-MM effects. On the other hand, immunotherapies seem attractive for yet incurable malignancies by chemotherapeutic agents such as MM and their clinical application has been studied. One such approach is a TNF-related apoptosis-inducing ligand (TRAIL)-mediated immunotherapy. In the present study, we therefore explored the role of BTZ on TRAIL receptor editing and its downstream signaling with special reference to endoplasmic reticulum (ER) stress and the cytotoxic effects of BTZ and anti-TRAIL receptor agonistic antibody in combination on MM cells. Most MM cells expressed DR4 but weakly DR5, while normal peripheral blood mononuclear cells expressed neither DR4 nor DR5. BTZ at 10 nM markedly up-regulated the surface levels of DR5 and its mRNA expression but not those of DR4 in MM cell lines and primary MM cells. Furthermore, BTZ decreased the levels of c-FLIP, an inhibitor of DISC, along with activation of caspase-8 and caspase-3, suggesting potentiation of the DR-mediated extrinsic apoptotic pathway. Consistently, BTZ and anti-DR5 agonistic antibody cooperatively enhanced the cytotoxicity against MM cells. BTZ induced phosphorylation of eIF2alpha, ATF4 and CHOP, along with disappearance of anti-apoptotic proteins including Mcl-1 in MM cells, suggesting the enhancement of ER stress and subsequent suppression of protein translation by BTZ. However, such induction of ER stress by BTZ was not observed in BTZ-resistant MM cell lines, KMS-11/BTZ and OPM-2/BTZ, with a point mutation in BTZ-binding proteasome beta5 subunit (Ri et al. Leukemia 2010). In KMS-11/BTZ and OPM-2/BTZ, surface protein as well as mRNA levels of DR5 were not up-regulated by BTZ, suggesting a critical role of ER stress in up-regulation of DR5 expression by BTZ. Because DR5 expression has been shown to be transcriptionally up-regulated by CHOP, the up-regulation of DR5 mRNA and protein in MM cells by BTZ is suggested to be at least in part due to CHOP induced by BTZ-mediated ER stress. Although BTZ exerts its anti-MM effects through induction of ER stress, the present study demonstrates that induction of ER stress by BTZ is also able to sensitize MM cells to TRAIL-mediated immunotherapy. Therefore, the combination of BTZ and TRAIL-mediated immunotherapy is warranted for further study. Disclosures: No relevant conflicts of interest to declare.

C/EBPb Is a Critical Mediator of Resistance to IMiD® Immunomodulatory Compounds and Affected by IMiD Compounds Via Control of Protein Translation

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 135-135
Author(s):  
Shirong Li ◽  
Rekha Pal ◽  
Sara Monaghan ◽  
Peter Schafer ◽  
Hongjiao Ouyang ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cell Proliferation ◽  
Cell Lines ◽  
Translational Control ◽  
Critical Role ◽  
Protein Translation ◽  
Thymidine Uptake ◽  
Double Labeling ◽  
Equity Ownership

Abstract Abstract 135 Background: Lenalidomide and pomalidomide are IMiD® immunomodulatory compounds that have been shown to be highly active in the treatment of multiple myeloma (MM). IMiD compounds exert their anti-tumor effects via acting on costimulatory proteins of T cells and NK cells, augmenting both the adaptive and innate immune system. But the mechanisms by which IMiD compounds directly inhibit MM cell proliferation are still unclear. Here we focused on the direct effects of IMiD compounds alone on MM cells. Results and Methods: We found that IMiDs, at concentrations as low as 0.01 μ M, induce significant inhibition of DNA synthesis in MM cells as shown by thymidine uptake. Since our previous work demonstrated that C/EBPβ is an important transcription factor which controls the growth and proliferation of myeloma cells, we analyzed the effects of IMiD compounds on C/EBPβ. We found that both pomalidomide and lenalidomide significantly decreased the protein level of C/EBPβ LAP-isoform in MM cell lines and primary MM cells. IMiD compound-induced suppression of C/EBPβ protein expression led to impaired transcription of the downstream IRF4, and subsequently to downregulation of BLIMP1 and XBP1, which are all critical for MM survival. To confirm our findings in vivo, we analyzed IRF4 expression by double labeling (IRF4+/CD138+) immunohistochemical staining of bone marrow biopsy samples of 23 myeloma patients prior to therapy and during therapy with lenalidomide. During lenalidomide therapy, the bone marrow MM cells showed a significantly weaker staining intensity for IRF4 in comparison to prior therapy. This was quantified by a significant (p<0.001) decrease of the staining score from 176 to 152, respectively. To confirm the critical role of C/EBPβ in MM we stably overexpressed C/EBPβ in MM cells. Overexpression of C/EBPβ prevented IMiD compound-induced inhibition of MM cell proliferation, indicating that C/EBPβ is critical in mediating resistance to IMiD compounds. This was supported by the fact that C/EBPβ was not down regulated in IMiD-resistant cell lines by IMiD treatment. Dissection of the C/EBPβ protein regulation revealed that IMiD compounds shut down C/EBPβ protein translation by decreasing eIF-4E. Knockdown experiments of eIF-4e resulted in downregulation of C/EBPβ, suggesting that C/EBPβ is under translational control in MM. Conclusions: Our studies, for the first time, provide evidence that IMiD compounds inhibit MM cell proliferation and survival by affecting the translation of C/EBPβ and subsequently multiple downstream transcription factors including IRF4, BLIMP1 and XBP1. Due to the critical role of C/EBPβ in mediating effects of IMiD compounds in MM, it might be a target to overcome drug resistance to IMiD compounds. The fact that pomalidomide can overcome resistance to lenalidomide in MM requires still further evaluation. Disclosures: Schafer: Celgene Corporation: Employment, Equity Ownership. Mapara:Gentium: Equity Ownership. Lentzsch:Celgene Corp: Research Funding.

scholarly journals A CRISPR/Cas9 genome editing pipeline in the EndoC-βH1 cell line to study genes implicated in beta cell function

2019 ◽  
Vol 4 ◽  
pp. 150 ◽  
Author(s):  
Antje K. Grotz ◽  
Fernando Abaitua ◽  
Elena Navarro-Guerrero ◽  
Benoit Hastoy ◽  
Daniel Ebner ◽  
...  
Keyword(s):  
Gene Expression ◽  
Beta Cell ◽  
Er Stress ◽  
Cell Line ◽  
Cell Lines ◽  
Target Genes ◽  
Gene Knockout ◽  
Mrna Levels ◽  
Beta Cell Line ◽  
Human Beta Cell

Type 2 diabetes (T2D) is a global pandemic with a strong genetic component, but most causal genes influencing the disease risk remain unknown. It is clear, however, that the pancreatic beta cell is central to T2D pathogenesis. In vitro gene-knockout (KO) models to study T2D risk genes have so far focused on rodent beta cells. However, there are important structural and functional differences between rodent and human beta cell lines. With that in mind, we have developed a robust pipeline to create a stable CRISPR/Cas9 KO in an authentic human beta cell line (EndoC-βH1). The KO pipeline consists of a dual lentiviral sgRNA strategy and we targeted three genes (INS, IDE, PAM) as a proof of concept. We achieved a significant reduction in mRNA levels and complete protein depletion of all target genes. Using this dual sgRNA strategy, up to 94 kb DNA were cut out of the target genes and the editing efficiency of each sgRNA exceeded >87.5%. Sequencing of off-targets showed no unspecific editing. Most importantly, the pipeline did not affect the glucose-responsive insulin secretion of the cells. Interestingly, comparison of KO cell lines for NEUROD1 and SLC30A8 with siRNA-mediated knockdown (KD) approaches demonstrate phenotypic differences. NEUROD1-KO cells were not viable and displayed elevated markers for ER stress and apoptosis. NEUROD1-KD, however, only had a modest elevation, by 34%, in the pro-apoptotic transcription factor CHOP and a gene expression profile indicative of chronic ER stress without evidence of elevated cell death. On the other hand, SLC30A8-KO cells demonstrated no reduction in KATP channel gene expression in contrast to siRNA silencing. Overall, this strategy to efficiently create stable KO in the human beta cell line EndoC-βH1 will allow for a better understanding of genes involved in beta cell dysfunction, their underlying functional mechanisms and T2D pathogenesis.

Targeting Proteinkinase C Alters ER-Stress and b-Catenin Signaling in Multiple Myeloma: Therapeutic Implications.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 258-258
Author(s):  
Marc S. Raab ◽  
Klaus Podar ◽  
Jing Zhang ◽  
Giovanni Tonon ◽  
Johannes H. Fruehauf ◽  
...  
Keyword(s):  
Cell Death ◽  
Stress Response ◽  
Growth Inhibition ◽  
Er Stress ◽  
Cell Lines ◽  
Wnt Pathway ◽  
Dependent Manner ◽  
P53 Family ◽  
Er Stress Response

Abstract We have previously shown that the novel orally available small molecule inhibitor of PKC enzastaurin (Eli Lilly and Company) inhibits MM cell growth, survival and angiogenesis both in vitro and in vivo. To date, however, the downstream effects contributing to growth inhibition and cell death remain to be determined. Here, we performed global gene expression profiling on enzastaurin treated MM cells and identified 200 Genes to be differentially regulated with a &gt; 2-fold cut off. Strikingly, two major groups of up-regulated probe sets were associated with either of two pathways - endoplasmatic reticulum (ER)-stress response or WNT-signaling. Importantly, MM cells, producing high levels of paraprotein, are highly susceptible to perturbation of ER function and protein folding. Moreover, PKC isoforms have been reported to directly regulate the canonical WNT pathway via phosphorylation of b-catenin (CAT), leading to its ubiquination and proteasomal degradation. Specifically, we fist evaluated the role of enzastaurin in mediating ER-stress in MM cells. The transcriptional up-regulation of genes involved in ER-stress (GADD153/CHOP, GADD34, ATF3), triggered by enzastaurin at 3h, was confirmed by western blot analysis, accompanied by induction of the molecular ER chaperone BiP/grp78, phosphorylation of eIF2a consistent with PERK activation, and up-regulation of p21. These events were preceded by an early (1h) increase of intracellular calcium levels, a hallmark of ER-stress, assessed by FLUO4 staining. These data suggest an important role of ER-stress response in the early growth inhibition of MM cells caused by enzastaurin. Second, we delineated effects of enzastaurin on WNT pathway in MM and other tumor cell lines. Upon enzastaurin treatment, CAT was dephosphorylated at Ser33, 37, 41 in a dose- and time-dependent manner in all cell lines tested (10 MM, 3 colon cancer, HeLa, as well as human embryonic kidney 293 cells). Consequently, accumulation of CAT occurred in both cytosolic and nuclear fractions of treated MM cells, associated with activated TOPflash LUC-reporter system, confirming nuclear transactivating activity. Specific inhibition of CAT by siRNA partially rescued HeLa, HEK 293, and MM cells from cell death induced by enzastaurin. Analysis of downstream target molecules revealed a CAT-dependent up-regulation of c-Jun, but not of c-Myc or Cyclin D1. c-Jun has been reported to stabilize p73, a pro-apoptotic p53-family member; CAT induction by enzastaurin led to p73 (but not p53) activation and was also abrogated by CAT-specific siRNA. In turn, specific knockdown of p73 by siRNA rescued cells from enzastaurin-induced apoptosis. Finally, ectopic overexpression of CAT in HeLa and MM cells induced c-Jun expression and p73 activation, followed by apoptotic cell death. Our studies therefore indicate that ER-stress response contributes to the immediate inhibition of proliferation by enzastaurin, followed by CAT accumulation leading to p73 activation, contributing to enzastaurin-mediated cell death. These findings provide a novel link between CAT and p53-family members. Moreover p73, which is only rarely mutated in human cancers, represents a novel therapeutic target in MM.

A Novel Long Non-Coding RNA, SNHG4 Complex With Eukaryotic Initiation Factor-4E and Regulate Aberrant Protein Translation In Mantle Cell Lymphoma: Implications For Novel Biomarker

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 81-81
Author(s):  
Guangzhen Hu ◽  
Thomas E Witzig ◽  
Mamta Gupta
Keyword(s):  
B Cell ◽  
Cell Lines ◽  
Rna Binding ◽  
Cell Lymphoma ◽  
Protein Translation ◽  
Rna Seq ◽  
Lymphoma Cells ◽  
Binding Motifs ◽  
Mantle Cell

Abstract Long noncoding RNAs (lncRNAs) are defined as RNA-like transcripts that are over 200 nucleotides and lack significant open reading frames. Some lncRNAs such as HOTAIR, MALAT1 and H19 have been found to be associated with clinical prognosis and are potential drivers of cancer progression in cancers of the breast, lung, and liver respectively. The role of lncRNAs in lymphoma is unknown. Dysregulation of eIF4E (a key component of the translation initiation complex eIF4F) influences global protein translation, especially the translation of “weak” mRNAs that can be malignancy-related. We and others have found that eIF4E is dysregulated in B-cell lymphoma. The aim of this study is to identify eIF4E-associated lncRNAs through next generation RNA-Sequencing (NGS RNA-Seq) and delineate their role in protein translation in lymphoma. RNA-immunoprecipitation (RNA-IP) was used to pull down eIF4E-bound lncRNA in lymphoma cells. eIF4E-bound lncRNAs were immunoprecipitated with eIF4E antibody or IgG control in Jeko, a mantle cell lymphoma (MCL) cell line and sent for microarray analysis and NGS-RNA-Seq for identification of lncRNAs. The microarray analysis showed that several lncRNAs were enriched with eIF4E antibody compared to IgG control. These included SNHG4 (13.6 fold), SNHG12 (4.8 fold), NCRNA00171 (4.8 fold) and IPW (4.6 fold), GNASAS (3.5 fold), SNHG7 (3.3 fold), NCRNA00182 (2.7 fold), NCRNA00094 (2.6 fold), NCRNA00188 (2.4 fold) and NCRNA00201 (2.1 fold). The binding of these lncRNAs to eIF4E was further confirmed by RT-PCR in Jeko, Mino and Granta MCL cell lines. Next, we looked the expression of these lncRNAs by qRT- PCR in the MCL cell lines and normal controls. We found SNHG4 and IPW to be overexpressed in all the MCL cell lines, while SNHG12 and NCRNA00201 were overexpressed in the selected cell lines. No significant difference was found for the expression of NCRNA00171 and NCRNA00182 in any of the MCL cell lines compared to controls. Overall, these data suggest that several lncRNA have altered expression in malignant B-cells. Considering that the microarray assay only covered a limited number of lncRNAs, we further confirmed eIF4E bound lncRNA by NGS RNA-Seq in Jeko MCL and normal control. The binding of 10/13 lncRNA mentioned above with eIF4E were found upregulated by NGS-RNA-Seq. In addition several novel lncRNAs such as SNHG1 (161.6), AC091814.2 (98.8) and RP11-304L19.5 (64.2) showed up in NGS-RNA-Seq data. These data suggest that lncRNAs, such as SNHG12, SNHG4, and SNHG1 bind to eIF4E with high affinity in malignant B-cells and might play a role in protein translation. We knocked down the expression of SNHG4 through siRNA and demonstrated that cell proliferation and global protein translation was inhibited in lymphoma cells. To further confirm the role of SNHG4 in translation regulation, a plasmid, which contains a renilla luciferase driven by SV40 promoter, was co-transfected with SNHG4 siRNA into Mino cells. The luciferase signal, decreased compared with the cells transfected with nontargeting siRNA. These data suggest that SNHG4 is involved in the regulation of protein translation. In order to clarify the mechanism of lncRNAs bound to eIF4E we searched for RNA binding sites or motifs in eIF4E protein using the web-based tools, BindN and PPRInt. Interestingly two RNA binding motifs, KNKRGGRWLITLNKQQRRS and SHADTATKSGSTTKNR, were found in eIF4E based on the prediction. To examine whether lncRNAs bind with eIF4E through these RNA binding motifs, an eIF4E mutant plasmid with both RNA binding motifs deleted (eIF4EDel), was constructed and transfected transiently into HEK-293T cells along with eIF4EWT plasmid. RNA-IP data showed that the lncRNAs SNHG12, SNHG4 and SNHG1 were not able to bind with eIF4E in eIF4EDel-transfected cells compared with that of eIF4EWT, suggesting that these lncRNAs complex with eIF4E through RNA-binding motifs within the eIF4E. Overall, our results show that the lncRNAs, SNHG1 and SNHG4 are able to bind with eIF4E and regulate protein translation. Since lncRNAs had been found to play roles in the regulation of gene expression, including transcription, splicing and mRNA stability, our results may broaden the view of the functional role of lncRNAs in translation in lymphoma cells and in other cancers. Furthermore, our results also suggested that SNHG4 lncRNAs might be served as potential biomarkers for MCL and other B cell lymphomas for translation therapy. Disclosures: No relevant conflicts of interest to declare.

The role of ZNF395 in renal cell carcinoma proliferation, migration, and invasion.

2016 ◽  
Vol 34 (2_suppl) ◽  
pp. 592-592 ◽  
Author(s):  
Chen Zhao ◽  
Christopher G. Wood ◽  
Jose A. Karam ◽  
Tapati Maity ◽  
Lei Wang
Keyword(s):  
Renal Cell Carcinoma ◽  
Tumor Growth ◽  
Cell Carcinoma ◽  
Cell Lines ◽  
Renal Cell ◽  
Migration And Invasion ◽  
Mrna Levels

592 Background: Zinc finger protein 395 (ZNF395) is frequently altered in several tumor types. However, the role of ZNF395 remains poorly studied in patients with clear cell renal cell carcinoma (RCC). In this study, we investigated the in vitro and in vivo role of ZNF395 in ccRCC. Methods: cBioPortal For Cancer Genomics was used to correlate the expression of ZNF395 with RCC patient clinical, pathological and molecular profiles. ZNF395 protein and mRNA levels were studied in several RCC cell lines in vitro. Subsequently, ZNF395 knockdown was performed in 786-O and UMRC3 RCC cells and overexpression was done in Caki-1 and 769-P RCC cells. We then evaluated ZNF395 modulation in these cell lines by in vitro MTT, migration and invasion assays. Finally, we studied the effect of ZNF395 knockout and overexpression in vivo using SCID xenograft models. Results: Patients with higher expression of ZNF395 experienced longer disease-free survival and overall survival. Using in vitro models, we confirmed that knockdown of ZNF395 decreased ZNF395 expression, and increased proliferation, migration and invasiveness of 786-O and UMRC3, while overexpression of ZNF395 increased ZNF395 expression, and reduced proliferation, migration and invasiveness of Caki-1 and 769-P. Using in vivo mouse models, knockdown of ZNF395 expression in 786-O promoted tumor growth while its overexpression in Caki-1 resulted in tumor growth inhibition. We are currently performing experiments to understand the process by which ZNF395 regulates ccRCC pathogenesis. Conclusions: Our data support the role of ZNF395 as an important tumor suppressor gene in the pathogenesis of RCC.

scholarly journals Smoothened Stabilizes and Protects TRAF6 from Proteosomal Degradation: A Novel Non-Canonical Role of Smoothened with Implications in Lymphoma Biology

Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. 646-646
Author(s):  
Changju QU ◽  
Amineh Vaghefi ◽  
Kranthi Kunkalla ◽  
Jennifer R Chapman ◽  
Yadong Liu ◽  
...  
Keyword(s):  
Cell Survival ◽  
Cell Lines ◽  
E3 Ligase ◽  
B Cell Lymphoma ◽  
Mrna Levels ◽  
Protein Levels ◽  
Multiple Cancers ◽  
Proteosomal Degradation ◽  
Hh Signaling

Abstract Tumor necrosis factor receptor-associated factor 6 (TRAF6), an (K63) E3-ligase, plays a crucial role in many biological processes and its activity is relevant in the biology of multiple cancers including diffuse large B cell lymphoma (DLBCL). Although molecules that trigger TRAF6 activation have been defined, those that stabilize TRAF6 levels and/or enhance TRAF6 function remain largely unclear. Previously, we found that activation of smoothened (SMO) with recombinant Hedgehog (Hh) ligand increased the binding between SMO with TRAF6, as well as TRAF6 protein levels (Blood 2013; 121:4718-28). In addition, transient overexpression of SMO resulted in increased K63-Ub of both TRAF6 and NEMO indicating stabilization of these proteins resulting in NF-kB activation. This is relevant, as more recently we found that TRAF6 amplifies pAKT signaling in DLBCL and that TRAF6 is the dominant E3 ligase for the K63-Ub of AKT in DLBCL. Moreover, TRAF6 recruitment to the cell membrane, and stabilization of its ubiquitination profile are facilitated by SMO. SMO is a member of the Frizzled-class G-protein-coupled receptor (GPCRs) and is traditionally known for its role as signal transducer in canonical Hedgehog (Hh) signaling. These observations prompted us to investigate whether the ability of SMO to increase TRAF6 levels is limited to ligand induced signaling, whether it contributes to chemoresistance in DLBCL cells, and whether SMO directly participates in controlling TRAF6 levels. To confirm the regulatory role of SMO in the TRAF6/AKT axis in DLBCL cells (HBL1 and HT) and further outline the nature of the underlying regulation, we measured the impact of activation of the Hh pathway with recombinant Shh ligand on TRAF6 levels, with and without SMO knockdown or recombinant SMO overexpression. Canonical Hh signaling results in the activation of the GLI1 transcription factor and the subsequent elevation of GLI1 mRNA levels is an established indicator of activation of the Hh pathway. However, neither SMO activation nor the knockdown of GLI1 had a significant impact on TRAF6 mRNA levels. These findings indicate that TRAF6 is not transcriptionally regulated by SMO signaling through GLI1 (canonical Hh signaling). In contrast, overexpression of SMO or siRNA knockdown of SMO resulted in an increase or decrease of TRAF6 protein levels, respectively. Consistent with the decrease of AKT activation (pAKT T308 and S473) after TRAF6 knockdown, the increase in TRAF6 levels that follows SMO overexpression resulted in an increase in the levels of AKT phosphorylation. Altogether, these observations suggest a post-translational regulation of TRAF6 by SMO. Indeed, stable knockdown of SMO dramatically reduces the half-life of TRAF6 in both HBL1 and HT cells in the presence of cyclohexamide. Furthermore, overexpression of SMO increases K63-Ub of both TRAF6 and AKT. In contrast, the SMO induced decrease in K48-Ub occurred only for TRAF6 but not for AKT. These data link the SMO-stimulated activation of TRAF6 to the enhancement of AKT signaling and protection of TRAF6 from proteasomal degradation. Mechanistically, we found that SMO, through its C-terminal tail, stabilizes TRAF6 and protects TRAF6 from proteosomal degradation, an effect mediated by ubiquitin-specific protease-8 (USP8). Importantly, this functional link between SMO and TRAF6 is reflected in DLBCL patient samples where high expression of both molecules correlates with poor prognosis. Resistance to DXR is a serious challenge in the treatment of DLBCL, and activated AKT is known to contribute to DXR resistance in multiple cancers including DLBCL. We evaluated whether SMO and TRAF6 support resistance to DXR in DLBCL cell lines. We exposed HT and HBL1 cells as well as their counterparts with stable knockdown of TRAF6 or SMO to DXR for 96hrs. Cell viability after exposure to DXR was determined by an Annexin V and PI staining assay. Silencing SMO or TRAF6 dramatically decreased cell survival after treatment with DXR. In summary, we report that SMO is needed to facilitate and maintain TRAF6-dependent elevated pAKT levels in DLBCL cell lines of germinal (GC) and non-GC subtypes, and that the SMO/TRAF6 axis contributes to DXR resistance in DLBCL. Our study reveals a novel and potential central cell survival signaling mechanism in which SMO stabilizes and protects TRAF6 from proteosomal degradation. Disclosures Lossos: Affimed: Research Funding.

scholarly journals Inhibition of Endoplasmic Reticulum Stress Reverses Synaptic Plasticity Deficits in Striatum of DYT1 Dystonia Mice

2021 ◽  
Author(s):  
Huaying Cai ◽  
Linhui Ni ◽  
Xingyue Hu ◽  
Xianjun Ding
Keyword(s):  
Endoplasmic Reticulum ◽  
Synaptic Plasticity ◽  
Er Stress ◽  
Critical Role ◽  
Stress Protein ◽  
Long Term Potentiation ◽  
Research Field ◽  
Protein Levels ◽  
Dyt1 Dystonia

Abstract Background & objectiveStriatal plasticity alterations caused by endoplasmic reticulum (ER) stress is supposed to be critically involved in the mechanism of DYT1 dystonia. In the current study, we expanded this research field by investigating the critical role of ER stress underlying synaptic plasticity impairment imposed by mutant heterozygous Tor1a+/- in a DYT1 dystonia mouse model.Methods & resultsLong-term depression (LTD) was failed to be induced, while long-term potentiation (LTP) was further strengthened in striatal spiny neurons (SPNs) from the Tor1a+/- DYT1 dystonia mice. Spine morphology analyses revealed a significant increase of both number of mushroom type spines and spine width in Tor1a+/- SPNs. In addition, increased AMPA receptor function and the reduction of NMDA/AMPA ratio in the postsynaptic of Tor1a+/- SPNs was observed, along with increased ER stress protein levels in Tor1a+/- striatum. Notably, ER stress inhibitors, tauroursodeoxycholic acid (TUDCA), could rescue LTD as well as AMPA currents.ConclusionThe current study illustrated the role of ER stress in mediating structural and functional plasticity alterations in Tor1a+/- SPNs. Inhibition of the ER stress by TUDCA is beneficial in reversing the deficits at the cellular and molecular levels. Remedy of dystonia associated neurological and motor functional impairment by ER stress inhibitors could be a recommendable therapeutic agent in clinical practice.

scholarly journals The Critical Role of PTEN Mutation in Cellular Process and Drug Selection of Endometrial Cancer

2020 ◽  
Author(s):  
Ying Liu ◽  
Jintuo Zhou ◽  
Peiguang Niu ◽  
Fanxiang Zeng ◽  
Ruihong Cai ◽  
...  
Keyword(s):  
Endometrial Cancer ◽  
Cell Lines ◽  
Mrna Levels ◽  
Drug Selection ◽  
Ppi Network ◽  
Kegg Analysis ◽  
Pten Mutation ◽  
Mannose Metabolism ◽  
Selection Of

Abstract Background: Phosphatase and tensin homolog (PTEN) is a frequently mutated genes found in endometrial cancer (EC), making it a potential biomarker for individualized treatment opinions. In this study, a method was designed to evaluate the role of the PTEN mutation in the prognosis and drug selection of EC. We identified the potential alterations in pathways and genes related to the mechanism. Methods: cBioPortal database was used to analyze the PTEN mutation status for EC patients. Kaplan-Meier was used to analyze the prognosis of PTEN mutation in EC patients. GDSC dataset was used to identified the drugs that sensitive to cell lines with PTEN mutation. DEGs between PTEN mutation and wide type group were identified using the edgeR package. GO and KEGG analysis were carried out using the DAVID database. GSEA v3.0 were used to dig out the differences in gene mRNA levels of biological function annotation and pathways between PTEN mutation and wide type patients. PPI network of DEGs was performed using STRING and then visualized using Cytoscope software (3.7.2).Results: Our results showed that PTEN mutation was carried in 68% of EC patients. The mRNA expression level of PTEN was lower in patients with PTEN mutation than that with wide type. Prognosis analysis showed that there were favorable overall survival and progression free survival in EC patients with PTEN mutation. Moreover, it is more sensitive to AKT inhibitor (Afuresertib and AZD5363), and Mcl-1 inhibitor (MIM1) on EC cell lines with PTEN mutation than that with wide type. A total of 216 genes were identified as DEGs. GO analysis showed that DEGs significantly enriched in chemical synaptic transmission, extracellular region, etc.. KEGG analysis suggested that DEGs significantly enriched in categories associated with metabolic progression. GSEA analysis identified signaling pathways including fatty acid metabolism, fructose and mannose metabolism, etc.. PPI network analysis identified top 10 genes and top three clusters.Conclusions: Multiple genes and pathways may play an important role in EC patients with PTEN mutation. These results provide a potential target and therapeutic strategies for patients with PTEN mutation.

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