DDIT3

Gene Summary

Gene:DDIT3; DNA damage inducible transcript 3
Aliases: CHOP, CEBPZ, CHOP10, CHOP-10, GADD153
Location:12q13.3
Summary:This gene encodes a member of the CCAAT/enhancer-binding protein (C/EBP) family of transcription factors. The protein functions as a dominant-negative inhibitor by forming heterodimers with other C/EBP members, such as C/EBP and LAP (liver activator protein), and preventing their DNA binding activity. The protein is implicated in adipogenesis and erythropoiesis, is activated by endoplasmic reticulum stress, and promotes apoptosis. Fusion of this gene and FUS on chromosome 16 or EWSR1 on chromosome 22 induced by translocation generates chimeric proteins in myxoid liposarcomas or Ewing sarcoma. Multiple alternatively spliced transcript variants encoding two isoforms with different length have been identified. [provided by RefSeq, Aug 2010]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:DNA damage-inducible transcript 3 protein
Source:NCBIAccessed: 10 March, 2017

Ontology:

What does this gene/protein do?
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Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 10 March 2017 using data from PubMed using criteria.

Literature Analysis

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Tag cloud generated 10 March, 2017 using data from PubMed, MeSH and CancerIndex

Specific Cancers (3)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: DDIT3 (cancer-related)

Zheng X, Jin X, Li F, et al.
Inhibiting autophagy with chloroquine enhances the anti-tumor effect of high-LET carbon ions via ER stress-related apoptosis.
Med Oncol. 2017; 34(2):25 [PubMed] Related Publications
Energetic carbon ions (CI) offer great advantages over conventional radiations such as X- or γ-rays in cancer radiotherapy. High linear energy transfer (LET) CI can induce both endoplasmic reticulum (ER) stress and autophagy in tumor cells under certain circumstances. The molecular connection between ER stress and autophagy in tumor exposed to high-LET radiation and how these two pathways influence the therapeutic effect against tumor remain poorly understood. In this work, we studied the impact of autophagy and apoptosis induced by ER stress following high-LET CI radiation on the radiosensitivity of S180 cells both in vitro and in vivo. In the in vitro experiment, X-rays were also used as a reference radiation. Our results documented that the combination of CI radiation with chloroquine (CQ), a special autophagy inhibitor, produced more pronounced proliferation suppression in S180 cells and xenograft tumors. Co-treatment with CI radiation and CQ could block autophagy through the IRE1/JNK/Beclin-1 axis and enhance apoptotic cell death via the activation of C/EBP homologous protein (CHOP) by the IRE1 pathway rather than PERK in vitro and in vivo. Thus, our study indicates that inhibiting autophagy might be a promising therapeutic strategy in CI radiotherapy via aggravating the ER stress-related apoptosis.

Sun X, Liao W, Wang J, et al.
CSTMP induces apoptosis and mitochondrial dysfunction in human myeloma RPMI8226 cells via CHOP-dependent endoplasmic reticulum stress.
Biomed Pharmacother. 2016; 83:776-784 [PubMed] Related Publications
BACKGROUND: The natural product tetramethylpyrazine (TMP) and resveratrol have a variety of biologic activities, including anti-cancer effects. However the pharmacological function of CSTMP (a newly designed and synthesized TMP and resveratrol derivative) in cancer have not been elucidated.
METHODS: In RPMI8226 cells, the cytotoxic effects and apoptosis were detected by MTT and Double staining for Annexin V-FITC and propidium iodide (PI). The protein and mRNA expression levels were detected by Real Time PCR and Western blot, respectively. The localization of cleaved caspase-12 was evaluated by immunofluorescent staining. The activation of caspase were measured by colorimetric assays and Western blot.
RESULTS: CSTMP showed significantly cytotoxic effects and induced apoptosis in RPMI8226 cells. Caspase activation, Cytochrome c release and Bax, Bcl-2 and Bcl-XL levels analyses demonstrated that the anti-cancer effect of CSTMP in RPMI8226 cells was mediated by promoting caspase- and mitochondria-dependent apoptosis. In addition, CSTMP induced the increased expression of endoplasmic reticulum (ER) stress related proteins (CHOP, GRP78, GRP94 and cleaved caspase-12) and the activation of multiple branches of ER stress transducers (PERK-eIF2α, IRE1α and ATF6). Moreover, knockdown of CHOP by siRNA markedly inhibited CSTMP-induced cytotoxic effects, caspases activity and mitochondrial dysfunction in RPMI8226 cells.
CONCLUSIONS: Our results indicated that CSTMP could induce apoptosis and mitochondrial dysfunction in RPMI8226 cells via CHOP-dependent ER stress.

Xu Y, Chen Z, Zhang G, et al.
HSP90B1 overexpression predicts poor prognosis in NSCLC patients.
Tumour Biol. 2016; 37(10):14321-14328 [PubMed] Related Publications
Non-small cell lung cancer (NSCLC) accounts for 85 % of lung cancer-related mortality worldwide. The heat shock protein 90B1 (HSP90B1) and DNA damage-inducible transcript 3 (DDIT3) are endoplasmic reticulum stress-related proteins that are associated with many malignancies. However, the roles of two proteins on NSCLC remain uncovered. To investigate the correlation between the expressions of HSP90B1 and DDIT3 and clinicopathological parameters of NSCLC as well as the significance of prognosis in NSCLC, a total of 143 NSCLC tissue samples and 45 control tissues samples were assessed. NSCLC patients were followed up from the day of surgery and ended by March 2014. The expressions of HSP90B1 and DDIT3 proteins were detected in all paraffin-embedded biopsy samples by immunochemistry. The HSP90B1 was highly expressed (65.2 %) in the 143 NSCLC patients, and its high expression was correlated with clinical stages (P = 0.001) and lymph node metastasis (P = 0.016). Similarly, DDIT3 was highly expressed in 43 (30.1 %) of 143 NSCLC patients, but only correlated with lymph node metastasis. Furthermore, Log-rank test suggested that high HSP90B1 expression may predict shorter survival (overall survival (OS)) and disease-free survival (DFS) for NSCLC patients. Cox model multivariate analyses indicated that HSP90B1 overexpression was an independent poor prognostic factor for both of OS and DFS. Therefore, HSP90B1 and DDIT3 may the potential biomarker to predict the NSCLC clinicopathological progress. Meanwhile, high HSP90B1 expression means poor prognosis, and HSP90B1 can be a promising prognosis factor for NSCLC.

Ma J, Yang YR, Chen W, et al.
Fluoxetine synergizes with temozolomide to induce the CHOP-dependent endoplasmic reticulum stress-related apoptosis pathway in glioma cells.
Oncol Rep. 2016; 36(2):676-84 [PubMed] Free Access to Full Article Related Publications
Although temozolomide (TMZ) is the most effective chemotherapy agent for glioma, chemotherapy resistance has limited its clinical use. Fluoxetine (FLT), which is widely used in cancer-related depression, has exhibited potent anticancer properties in different cancer cell types. The aim of this study was i) to evaluate the antitumor mechanism of FLT, and ii) to further evaluate the effects of a combination of FLT and TMZ on glioma cells. Glioma cell lines were exposed to FLT and/or TMZ. Cell viability and apoptosis were examined by CCK-8 assay, flow cytometry and caspase-3 activity assay, respectively. The expression of endoplasmic reticulum-stress (ERS) apoptosis-related proteins was measured using real-time PCR and western blotting. Synergism between the two drugs was evaluated by the combination index (CI) through CompuSyn software. FLT significantly and dose-dependently inhibited the proliferation of various glioma cell lines, and rat glioma C6 cells had a highly sensitive response to the addition of FLT. FLT treatment increased the early apoptosis rate, induced typical apoptotic morphology in the C6 cells and activated caspase-3 with no change in the mitochondrial membrane potential. Further study showed that FLT activated the ERS marker, CHOP. This induction was associated with activation of the PERK-eIF2α-ATF4 and ATF6 cascade. Concomitantly, GADD34, a downstream molecule of CHOP, was also increased. Combined FLT and TMZ treatment showed a synergistic cytotoxic effect in the C6 glioma cells. Knockdown of CHOP expression abolished the synergistic effect of FLT and TMZ in the C6 cells, which suggests that FLT may sensitize glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. These results revealed that FLT induced glioma cell apoptosis and sensitized glioma cells to TMZ through activation of the CHOP‑dependent apoptosis pathway. The present study provides a primary basis for using the combination of these drugs in patients with advanced glioma.

Lee HM, Kim CW, Hwang KA, et al.
Three components of cigarette smoke altered the growth and apoptosis of metastatic colon cancer cells via inducing the synthesis of reactive oxygen species and endoplasmic reticulum stress.
Environ Toxicol Pharmacol. 2016; 45:80-9 [PubMed] Related Publications
Cigarette smoke (CS) is a well-known risk factor for carcinogenesis and has been found to be related to the occurrence and development of colon cancer. In this study, the effect of formaldehyde (FA), benzene (Bz), and isoprene (IP), which are included in main components of CS, on cell viability and apoptosis of SW620 colorectal cancer cells was examined to identify the connection between CS components and colon cancer. In cell viability assay, FA, Bz, and IP decreased cell viability of SW620 cells in a dose dependent manner. In Western blot assay, the protein expression of cell cycle related genes, cyclin D1 & E1, was decreased by FA, Bz, and IP, which corresponded to their inhibitory effect on cell viability. In addition, FA, Bz, and IP increased the protein expression of pro-apoptotic genes, C/EBP homologous protein (CHOP) and Bax, and reduced the protein expression of anti-apoptotic gene, Bcl-2. In reactive oxygen species (ROS) assay using dichlorofluorescin diacetate (DCFH-DA), FA, Bz, and IP increased the ROS production in SW620 cells. In the measurement of apoptotic cells, the numbers of apoptotic cells were increased by the treatment of FA, Bz, and IP. As CHOP is an endoplasmic reticulum (ER)-stress related apoptosis marker of which production is induced by ROS, it was considered that these CS components induce apoptosis of SW620 cells by increasing ROS synthesis and ER-stress. Taken together, these results showed that CS components, i.e., FA, Bz, and IP, inhibited the cell viability of SW620 cells by down-regulating the protein expression of cyclin D1 & E1 and induced apoptosis of SW620 cells by increasing ROS production and simultaneously activating ER-stress.

Dilshara MG, Jayasooriya RG, Park SR, et al.
Caffeic acid phenethyl ester enhances TRAIL-mediated apoptosis via CHOP-induced death receptor 5 upregulation in hepatocarcinoma Hep3B cells.
Mol Cell Biochem. 2016; 418(1-2):13-20 [PubMed] Related Publications
Caffeic acid phenethyl ester (CAPE) exhibits various pharmaceutical properties, including anti-bacterial, anti-inflammatory, anti-viral, anti-cancer, and anti-oxidative activity. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been a promising anti-cancer agent that preferentially induces cancer cell apoptosis with negligible cytotoxicity toward normal cells. Therefore, the present study investigated whether CAPE promotes TRAIL-mediated cytotoxicity in hepatocarcinoma Hep3B cells. The present study demonstrated that CAPE sensitized TRAIL-mediated cell death in Hep3B carcinoma cells. The percentages of the apoptotic cells and annexin-V(+) cells significantly increased in combined treatment with CAPE and TRAIL (CAPE/TRAIL). Treatment with pancaspase inhibitor, z-VAD-fmk, attenuated CAPE/TRAIL-induced apoptosis, suggesting that the combined treatment triggers caspase-dependent apoptosis. Additionally, we found that CAPE stimulated the expression of death receptor 5 (DR5) and treatment with DR5/Fc chimera protein significantly blocked CAPE/TRAIL-induced apoptosis, which indicates that CAPE/TRAIL stimulated apoptosis through the binding of TRAIL to DR5. Moreover, expression of transcription factor C/EBP homologous protein (CHOP) markedly increased in response to CAPE and transient knockdown of CHOP abolished CAPE/TRAIL-mediated apoptosis. These results suggest that CHOP is a key regulator in CAPE/TRAIL-mediated apoptosis. Taken together, the present study found that CAPE significantly enhanced TRAIL-mediated apoptosis in Hep3B carcinoma cells and suggested that CAPE has promising potential in chemoprevention of hepatocellular carcinomas.

Sobhakumari A, Orcutt KP, Love-Homan L, et al.
2-Deoxy-d-glucose Suppresses the In Vivo Antitumor Efficacy of Erlotinib in Head and Neck Squamous Cell Carcinoma Cells.
Oncol Res. 2016; 24(1):55-64 [PubMed] Free Access to Full Article Related Publications
Poor tumor response to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is a significant challenge for effective treatment of head and neck squamous cell carcinoma (HNSCC). Therefore, strategies that may increase tumor response to EGFR TKIs are warranted in order to improve HNSCC patient treatment and overall survival. HNSCC tumors are highly glycolytic, and increased EGFR signaling has been found to promote glucose metabolism through various mechanisms. We have previously shown that inhibition of glycolysis with 2-deoxy-d-glucose (2DG) significantly enhanced the antitumor effects of cisplatin and radiation, which are commonly used to treat HNSCC. The goal of the current studies is to determine if 2DG will enhance the antitumor activity of the EGFR TKI erlotinib in HNSCC. Erlotinib transiently suppressed glucose consumption accompanied by alterations in pyruvate kinase M2 (PKM2) expression. 2DG enhanced the cytotoxic effect of erlotinib in vitro but reversed the antitumor effect of erlotinib in vivo. 2DG altered the N-glycosylation status of EGFR and induced the endoplasmic reticulum (ER) stress markers CHOP and BiP in vitro. Additionally, the effects of 2DG + erlotinib on cytotoxicity and ER stress in vitro were reversed by mannose but not glucose or antioxidant enzymes. Lastly, the protective effect of 2DG on erlotinib-induced cytotoxicity in vivo was reversed by chloroquine. Altogether, 2DG suppressed the antitumor efficacy of erlotinib in a HNSCC xenograft mouse model, which may be due to increased cytoprotective autophagy mediated by ER stress activation.

Krętowski R, Borzym-Kluczyk M, Stypułkowska A, et al.
Low glucose dependent decrease of apoptosis and induction of autophagy in breast cancer MCF-7 cells.
Mol Cell Biochem. 2016; 417(1-2):35-47 [PubMed] Free Access to Full Article Related Publications
Cancer cells have developed a number of adaptation mechanisms involving the signal activation of the transduction pathways, which promotes the progression and metastasis. Our results showed that the percentage of apoptotic MCF-7 cells incubated in the low glucose medium for 48 h was lower in comparison to those cultured in the high glucose medium, despite the high expression of the proapoptotic transcription factor-CHOP. Furthermore, the MCF-7 cells incubated in the low glucose medium for 48 h showed a higher expression of NF-κB p100/p52 subunits compared to cells incubated in the high glucose medium. Moreover, our findings demonstrated that the shortage of glucose strongly induces autophagy in MCF-7 cells. The activation of this process is not associated with the changes in the expression of mTOR kinase. We suggest, that the antiapoptotic chaperone ORP150 induction, transcription factor NF-κB2 activation, and increased autophagy constitute mechanisms protecting the MCF-7 cells against apoptosis.

Kim JK, Kang KA, Ryu YS, et al.
Induction of Endoplasmic Reticulum Stress via Reactive Oxygen Species Mediated by Luteolin in Melanoma Cells.
Anticancer Res. 2016; 36(5):2281-9 [PubMed] Related Publications
BACKGROUND: This study aimed to investigate whether luteolin, a flavonoid, induces apoptosis in human melanoma cells via endoplasmic reticulum (ER) stress.
MATERIALS AND METHODS: To investigate the effects of luteolin in human melanoma cells, the anti-proliferation, apoptosis, ER stress induction and reactive oxygen species (ROS) generation were evaluated using MTT, Hoechst 33342, ER-tracker Blue White DPX and DCF-DA staining assays, respectively.
RESULTS: Luteolin inhibited cell proliferation and increased apoptotic body formation. Luteolin induced ER stress, as shown by ER staining and mitochondrial Ca(2+) overloading. Luteolin increased expression of the ER stress-related proteins; protein kinase RNA-like ER kinase, phospho eukaryotic translation initiation factor 2α, activating transcription factor (ATF) 6, CCAAT/enhancer-binding protein-homologous protein (CHOP), and cleaved caspase 12. Furthermore, luteolin increased the level of intracellular ROS, leading to ROS-mediated apoptosis and ER stress. However, N-acetyl cysteine, a ROS scavenger, decreased ROS levels, apoptosis, and ER stress induced by luteolin treatment. In addition, knockdown of CHOP and ATF6 by small-interfering RNA inhibited luteolin-induced cell death.
CONCLUSION: Luteolin induces apoptosis by ER stress via increasing ROS levels.

Park JS, Lim CJ, Bang OS, Kim NS
Ethanolic extract of Descurainia sophia seeds sensitizes A549 human lung cancer cells to TRAIL cytotoxicity by upregulating death receptors.
BMC Complement Altern Med. 2016; 16:115 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Our previous genome-wide gene expression analysis revealed that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) death receptors 4 (DR4) and 5 (DR5) are markedly upregulated by the ethanolic extract of D. sohia seeds (EEDS) in A549 TRAIL-refractory cancer cells. In the present study, we investigated whether the EEDS-mediated upregulation of TRAIL death receptors was associated with increased TRAIL-mediated toxicity in A549 cells in vitro.
METHODS: Cell proliferation and viability were determined by an automatic cell counter. Gene silencing was performed by introducing small interfering RNA into cells. Expression changes of cellular proteins were determined by western blot analysis. Apoptotic cell death was monitored by western blot analysis. Analysis of variance followed by the post-hoc Dunnett's test was used to compare the data.
RESULTS: EEDS treatment increased both mRNA and protein levels of DR4 and DR5 in the TRAIL refractory A549 cells. Co-treatment of A549 cells with sub-lethal dose of EEDS and recombinant TRAIL increased the apoptotic cell death. Upregulation of DR5 by EEDS was mediated by an endoplasmic reticulum stress-induced transcription factor, CCAAT/enhancer-binding protein homologous protein (CHOP), and knockdown of CHOP expression inhibited EEDS-induced DR5 upregulation and abolished the EEDS-associated increase in TRAIL toxicity in A549 cells.
CONCLUSIONS: EEDS can sensitize A549 cells to TRAIL cytotoxicity by upregulation of TRAIL death receptors. Our findings suggested that EEDS is a good initial herbal source for the development of an anticancer supplement for anticancer therapeutics associated with TRAIL.

Zhu YQ, Wang BY, Wu F, et al.
Influence of Tanshinone IIA on the Apoptosis of Human Esophageal Ec-109 Cells.
Nat Prod Commun. 2016; 11(1):17-9 [PubMed] Related Publications
The induced-apoptosis effect and mechanism of human esophageal cancer Ec-109 cells via tanshinone IIA was investigated. The Ec-109 cells were cultured in vitro with different concentrations of tanshinone IIA (2 µg/mL, 4 µg/mL, or 8 µg/mL) for 12, 24, 36, and 48 hours. MTT assay was used to evaluate the proliferative inhibition rate of tanshinone IIA on esophageal Ec-109 cells. After 24 hours of culturing in vitro, a control group was assigned. The apoptosis rate was detected by the AO/EB and annexin V-FITC/propidium iodide assay, and the protein levels of Caspase-4 and CHOP were determined by the Western blot technique. MTT data showed that tanshinone IIA could significantly inhibit the proliferation of Ec-109 cells with a dose- and time-dependent mode. Compared with the control group, tanshinone IIA could apparently induce apoptosis of Ec-109 cells, and the level of Caspase-4 and CHOP (p < 0.01) obviously increased. Tanshinone IIA can significantly induce the apoptosis of Ec-109 cells, which may take effect by the stress pathway of the endoplasmic reticulum.

Kim EO, Kang SE, Im CR, et al.
Tanshinone IIA induces TRAIL sensitization of human lung cancer cells through selective ER stress induction.
Int J Oncol. 2016; 48(5):2205-12 [PubMed] Related Publications
Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promised anticancer medicine targeting only the tumor, most cancers show resistance to TRAIL-induced apoptosis. For this reason, new therapeutic strategies to overcome the TRAIL resistance are required for more effective tumor treatment. In the present study, potential of tanshinone IIA as a TRAIL sensitizer was evaluated in human non-small cell lung cancer (NSCLC) cells. NSCLC cells showed resistance to TRAIL-mediated cell death, but combination treatment of Tanshinone IIA and TRAIL synergistically decreased cell viability and increased apoptosis in TRAIL-resistant NSCLC cells. Tanshinone IIA greatly induced death receptor 5 (DR5), but not death receptor 4 (DR4). Furthermore, DR5 knockdown attenuated the combination treatment of tanshinone IIA with TRAIL-mediated cell death in human NSCLC cells. Tanshinone IIA also increased CHOP and activated the PERK-ATF4 pathway suggesting that tanshinone IIA increased DR5 and CHOP by activating the PERK-ATF4 pathway. Tanshinone IIA also downregulated phosphorylation of STAT3 and expression of survivin. Taken together, these results indicate that tanshinone IIA increases TRAIL-induced cell death via upregulating DR5 and downregulating survivin mediated by, respectively, selective activation of PERK/ATF4 and inhibition of STAT3, suggesting combinatorial intervention of tanshinone IIA and TRAIL as a new therapeutic strategy for human NSCLC.

Pan Y, Liu G, Xiao J, et al.
A novel curcuminoid exhibits enhanced antitumor activity in nasopharyngeal carcinoma.
Int J Oncol. 2016; 48(5):2175-83 [PubMed] Related Publications
Curcumin shows growth-inhibition against tumor cells through multi-target mechanisms. Nevertheless, the poor stability and pharmacokinetics considerably limit its clinical functions. Increased effort has been put into the chemical alteration of curcumin to find potential analogues with improved bioavailability and antitumor activities. In this study, the antitumor activity of a novel curcuminoid (B63) in nasopharyngeal carcinoma (NPC) was examined. The MTT and colony formation assays were used to detect NPC cell viability and proliferation. Flow cytometry was used to detect cell cycle distribution. The Annexin V/PI staining assay and cleavage PARP and cleavage caspase-3 expression were used to examine apoptosis. Western blotting was used to examine the protein expression of endoplasmic reticulum (ER) stress pathway markers, XBP-1, ATF-4 and CHOP. The suppressive effect of B63 on tumor growth was examined in vivo by subcutaneously inoculated NPC in a tumor model using nude mice. Treatment with B63 potentially caused growth inhibition and apoptosis in NPC cells in a dose- and time-responsive manner. Its antitumor effect was associated with the ER stress activation. Nevertheless, the same dose of curcumin did not activate ER stress. In addition, knockdown of Chop attenuated B63-induced cell viability inhibition, suggesting that the apoptotic pathway is ER stress-dependent. The tumor volume and weight were significantly reduced by pretreating the NPC cells with B63 before implantation in the in vivo mouse model. B63 exhibited a more potent antitumor action than curcumin in NPC. These observations on the novel compound B63 indicate a novel candidate for NPC therapy.

Wang D, Chen Q, Liu B, et al.
Ellagic acid inhibits proliferation and induces apoptosis in human glioblastoma cells.
Acta Cir Bras. 2016; 31(2):143-9 [PubMed] Related Publications
PURPOSE: To investigate the anticancer activity of ellagic acid (EA) in U251 human glioblastoma cells and its possible molecular mechanism.
METHODS: The cells were treated with EA at various concentrations for different time periods. Cell viability and cell proliferation were detected by cell counting kit-8(CCK-8) assay and live/dead assay respectively. Cell apoptosis were measured with Annexin V-FITC/PI double staining method by flow cytometry and Mitochondrial membrane potential assay separately. Cell cycle was measured with PI staining method by flow cytometry. The expressions of Bcl-2, Survivin, XIAP, Caspase-3, Bax, JNK, p-JNK, ERK1/2, p-ERK1/2, p38, p-p38, DR4, DR5, CHOP and GRP78-related proteins were detected by western blot after EA treatment.
RESULTS: Cell viability and proliferation of glioblastoma cells treated with EA were significantly lower than the control group. EA caused robust apoptosis of the glioblastoma cells compared to the control group. EA significantly decreased the proportion at G0/G1 phases of cell cycling accompanied by increased populations at S phase in U251 cell lines. And the expressions of anti-apoptotic proteins were dramatically down-regulated.
CONCLUSION: Ellagic acid potentially up-regulated DR4, DR5 and MAP kinases (JNK, ERK1/2 and p38). EA also caused significant increase in the expressions of CHOP and GRP78. Our findings suggest that EA would be beneficial for the treatment of glioblastoma.

Wu CF, Seo EJ, Klauck SM, Efferth T
Cryptotanshinone deregulates unfolded protein response and eukaryotic initiation factor signaling in acute lymphoblastic leukemia cells.
Phytomedicine. 2016; 23(2):174-80 [PubMed] Related Publications
BACKGROUND: Unfolded protein responses (UPR) determine cell fate and are recognized as anticancer targets. In a previous research, we reported that cryptotanshinone (CPT) exerted cytotoxic effects toward acute lymphoblastic leukemia cells through mitochondria-mediated apoptosis.
PURPOSE: In the present study, we further investigated the role of UPR in CPT-induced cytotoxicity on acute lymphoblastic leukemia cells by applying tools of pharmacogenomics and bioinformatics.
METHODS: Gene expression profiling was performed by mRNA microarray hybridization. Potential transcription factor binding motifs were identified in the promoter regions of the deregulated genes by Cistrome software. Molecular docking on eIF-4A and PI3K was performed to investigate the inhibitory activity of CPT on translation initiation.
RESULTS: CPT regulated genes related to UPR and eIF2 signaling pathways. The DNA-Damage-Inducible Transcript 3 (DDIT3) gene, which is activated as consequence of UPR malfunction during apoptosis, was induced and validated by in vitro experiments. Transcription factor binding motif analysis of the microarrary-retrieved deregulated genes in the promoter region emphasized the relevance of transcription factors, such as ATF2, ATF4 and XBP1, regulating UPR and cell apoptosis. Molecular docking suggested inhibitory effects of CPT by binding to eIF-4A and PI3K providing evidence for a role of CPT's in the disruption of protein synthesis.
CONCLUSION: CPT triggered UPR and inhibited protein synthesis via eIF-mediated translation initiation, potentially supporting CPT-induced cytotoxic effects toward acute leukemia cells.

Weng S, Zhou L, Deng Q, et al.
Niclosamide induced cell apoptosis via upregulation of ATF3 and activation of PERK in Hepatocellular carcinoma cells.
BMC Gastroenterol. 2016; 16:25 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Hepatocellular carcinoma (HCC) is one of most common and aggressive human malignancies in the world, especially, in eastern Asia, and its mortality is very high at any phase. We want to investigate mechanism of niclosamide inducing cell apoptosis in HCC.
METHODS: Two hepatoma cell lines were used to evaluate activity of niclosamide inducing cell apoptosis and study its mechanism. Quantitative real-time PCR and western blotting were used in analysis of genes expression or protein active regulated by niclosamide.
RESULTS: Niclosamide remarkably induced cell apoptosis in hepatoma cells. Furthermore, our study revealed that RNA-dependent protein kinase-like kinase (PERK) is activated and its expression is up-regulated in HCC cells which are exposed to niclosamide. niclosamide also significantly increase activating transcription factor 3 (ATF3), activating transcription factor 4 (ATF4) and CCAAT/enhancer-binding protein-homologous protein (CHOP) expression in HCC cells. It's suggested that the function of niclosamide was abrogated by PERK inhibitor or absent ATF3. Expression of PERK and CHOP is correlated with ATF3 level in the cells.
CONCLUSION: Taken together, our results indicate that ATF3 plays an integral role in ER stress activated and cell apoptosis induced by niclosamide in HCC cells. In this study, the new mechanism of niclosamide as anti-cancer we investigated, too.

Jiang L, Zang D, Yi S, et al.
A microRNA-mediated decrease in eukaryotic initiation factor 2α promotes cell survival during PS-341 treatment.
Sci Rep. 2016; 6:21565 [PubMed] Free Access to Full Article Related Publications
MicroRNAs (miRs) play pivotal roles in carcinogenesis and endoplasmic reticulum (ER) that performs the folding, modification and trafficking of proteins targeted to the secretory pathway. Cancer cells often endure ER stress during tumor progression but use the adaptive ER stress response to gain survival advantage. Here we report: (i) A group of miRs, including miR-30b-5p and miR-30c-5p, are upregulated by proteasome inhibitor PS-341 treatment, in HepG2 and MDA-MB-453 cells. (ii) Two representative PS-341-induced miRs: miR-30b-5p and miR-30c-5p are found to promote cell proliferation and anti-apoptosis in both tumor cells. (iii) eIF2α is confirmed as the congenerous target of miR-30b-5p and miR-30c-5p, essential to the anti-apoptotic function of these miRs. (iv) Upregulation of miR-30b-5p or miR-30c-5p, which occurs latter than the increase of phosphorylated eIF2α (p-eIF2α) in the cell under ER stress, suppresses the p-eIF2α/ATF4/CHOP pro-apoptotic pathway. (v) Inhibition of the miR-30b-5p or miR-30c-5p sensitizes the cancer cells to the cytotoxicity of proteasome inhibition. In conclusion, we unravels a new miRs-based mechanism that helps maintain intracellular proteostasis and promote cell survival during ER stress through upregulation of miR-30b-5p and miR-30c-5p which target eIF2α and thereby inhibit the p-eIF2α/ATF4/CHOP pro-apoptotic pathway, identifying miR-30b-5p and miR-30c-5p as potentially new targets for anti-cancer therapies.

Gupta S, Gouw L, Wright J, et al.
Phase II study of amrubicin (SM-5887), a synthetic 9-aminoanthracycline, as first line treatment in patients with metastatic or unresectable soft tissue sarcoma: durable response in myxoid liposarcoma with TLS-CHOP translocation.
Invest New Drugs. 2016; 34(2):243-52 [PubMed] Related Publications
PURPOSE: Amrubicin is a third generation synthetic 9-aminoanthracycline that specifically inhibits topoisomerase II. Amrubicin preferentially concentrates in tumor cells leading to tumor cell death without causing cardiac toxicity. This phase II multicenter study was done to evaluate the efficacy and tolerability of amrubicin in advanced soft tissue sarcoma (STS).
PATIENTS AND METHODS: 24 eligible patients with chemotherapy-naive metastatic or unresectable STS were treated with amrubicin 40 mg/m(2) intravenously daily for three consecutive days in 21 days cycles with growth factor support. Patients continued to receive treatment, as long as it was tolerated, in the absence of significant disease progression. The disease was followed on imaging scans every 6 weeks. The primary endpoint of the study was the best overall response rate.
RESULTS: The best overall response rate was 13% in 23 evaluable patients. Median progression-free survival was 5.8 months, and median overall survival was 26 months. Grade 3 to 4 toxicities of febrile neutropenia and anemia occurred in 21% of treated patients. One patient with metastatic myxoid liposarcoma with TLS-CHOP translocation had a durable response and received 40 cycles of amrubicin. There was no significant cardiac toxicity.
CONCLUSIONS: Amrubicin has efficacy comparable to doxorubicin in adult STS, is well tolerated and has no significant cardiac toxicity up to a cumulative dose of 4800 mg /m(2). Topoisomerase II inhibition with amrubicin warrants further study as a potential 'targeted therapy' for TLS-CHOP-translocated myxoid liposarcoma. Results from this trial favor the use of amrubicin for the treatment of STS.

Sunami Y, Ringelhan M, Kokai E, et al.
Canonical NF-κB signaling in hepatocytes acts as a tumor-suppressor in hepatitis B virus surface antigen-driven hepatocellular carcinoma by controlling the unfolded protein response.
Hepatology. 2016; 63(5):1592-607 [PubMed] Related Publications
UNLABELLED: Chronic hepatitis B virus (HBV) infection remains the most common risk factor for hepatocellular carcinoma (HCC). Efficient suppression of HBV viremia and necroinflammation as a result of nucleos(t)ide analogue treatment is able to reduce HCC incidence; nevertheless, hepatocarcinogenesis can occur in the absence of active hepatitis, correlating with high HBV surface antigen (HBsAg) levels. Nuclear factor κB (NF-κB) is a central player in chronic inflammation and HCC development. However, in the absence of severe chronic inflammation, the role of NF-κB signaling in HCC development remains elusive. As a model of hepatocarcinogenesis driven by accumulation of HBV envelope polypeptides, HBsAg transgenic mice, which show no HBV-specific immune response, were crossed to animals with hepatocyte-specific inhibition of canonical NF-κB signaling. We detected prolonged, severe endoplasmic reticulum stress already at 20 weeks of age in NF-κB-deficient hepatocytes of HBsAg-expressing mice. The unfolded protein response regulator binding immunoglobulin protein/78-kDa glucose-regulated protein was down-regulated, activating transcription factor 6, and eIF2α were activated with subsequent overexpression of CCAAT/enhancer binding protein homologous protein. Notably, immune cell infiltrates and liver transaminases were unchanged. However, as a result of this increased cellular stress, insufficient hepatocyte proliferation due to G1 /S-phase cell cycle arrest with overexpression of p27 and emergence of ductular reactions was detected. This culminated in increased DNA damage already at 20 weeks of age and finally led to 100% HCC incidence due to NF-κB inhibition.
CONCLUSION: The role of canonical NF-κB signaling in HCC development depends on the mode of liver damage; in the case of HBsAg-driven hepatocarcinogenesis, NF-κB in hepatocytes acts as a critical tumor suppressor by augmenting the endoplasmic reticulum stress response.

Su HY, Waldron RT, Gong R, et al.
The Unfolded Protein Response Plays a Predominant Homeostatic Role in Response to Mitochondrial Stress in Pancreatic Stellate Cells.
PLoS One. 2016; 11(2):e0148999 [PubMed] Free Access to Full Article Related Publications
Activated pancreatic stellate cells (PaSC) are key participants in the stroma of pancreatic cancer, secreting extracellular matrix proteins and inflammatory mediators. Tumors are poorly vascularized, creating metabolic stress conditions in cancer and stromal cells that necessitate adaptive homeostatic cellular programs. Activation of autophagy and the endoplasmic reticulum unfolded protein response (UPR) have been described in hepatic stellate cells, but the role of these processes in PaSC responses to metabolic stress is unknown. We reported that the PI3K/mTOR pathway, which AMPK can regulate through multiple inputs, modulates PaSC activation and fibrogenic potential. Here, using primary and immortalized mouse PaSC, we assess the relative contributions of AMPK/mTOR signaling, autophagy and the UPR to cell fate responses during metabolic stress induced by mitochondrial dysfunction. The mitochondrial uncoupler rottlerin at low doses (0.5-2.5 μM) was added to cells cultured in 10% FBS complete media. Mitochondria rapidly depolarized, followed by altered mitochondrial dynamics and decreased cellular ATP levels. This mitochondrial dysfunction elicited rapid, sustained AMPK activation, mTOR pathway inhibition, and blockade of autophagic flux. Rottlerin treatment also induced rapid, sustained PERK/CHOP UPR signaling. Subsequently, high doses (>5 μM) induced loss of cell viability and cell death. Interestingly, AMPK knock-down using siRNA did not prevent rottlerin-induced mTOR inhibition, autophagy, or CHOP upregulation, suggesting that AMPK is dispensable for these responses. Moreover, CHOP genetic deletion, but not AMPK knock-down, prevented rottlerin-induced apoptosis and supported cell survival, suggesting that UPR signaling is a major modulator of cell fate in PaSC during metabolic stress. Further, short-term rottlerin treatment reduced both PaSC fibrogenic potential and IL-6 mRNA expression. In contrast, expression levels of the angiogenic factors HGF and VEGFα were unaffected, and the immune modulator IL-4 was markedly upregulated. These data imply that metabolic stress-induced PaSC reprogramming differentially modulates neighboring cells in the tumor microenvironment.

Yuan S, Qu L, Shou C
N-Terminal Polypeptide of Annexin A2 Decreases Infection of Mycoplasma hyorhinis to Gastric Cancer Cells.
PLoS One. 2016; 11(1):e0147776 [PubMed] Free Access to Full Article Related Publications
Mycoplasma infection in human and its contamination in cell cultures are worldwide problems. The drugs currently available for preventing or treating mycoplasma infection suffer from low sensitivity, strong resistance and high toxicity. Our previous work showed that Mycoplasma hyorhinis (M. hyorhinis) infection was mediated by the interaction between p37 of M. hyorhinis and Annexin A2 (ANXA2) of host cells, however the translational value of this mechanism was unknown. Herein, we synthesized the N-terminal of ANXA2 polypeptide (A2PP) and found that A2PP could decrease the infection of M. hyorhinis to gastric cancer cells and block M. hyorhinis infection-induced cell migration. Furthermore, we found that A2PP could reduce M. hyorhinis contamination of passage cells. Moreover, compared with the commercial antibiotics commonly used in cell culture to prevent M. hyorhinis infection, A2PP demonstrated a more effectiveness but a low toxicity on cell growth. Thus, our study for the first time revealed A2PP's potential for the treatment and prevention of M. hyorhinis infection.

Sharma K, Ishaq M, Sharma G, et al.
Pentoxifylline triggers autophagy via ER stress response that interferes with Pentoxifylline induced apoptosis in human melanoma cells.
Biochem Pharmacol. 2016; 103:17-28 [PubMed] Related Publications
Pentoxifylline (PTX), a non-specific phosphodiesterase inhibitor is known to inhibit the growth of various cancer cells including melanoma. Here in this study, we have found that PTX induces autophagy in human melanoma cell lines (A375 and MeWo). Induction of autophagy is associated with the increase in Atg5 expression as knockdown of Atg5 effectively inhibited PTX mediated autophagy. A decrease in mTOR activation was also observed after PTX treatment. We observed that autophagy was activated as a downstream effector mechanism of ER stress induced by PTX. ER stress response was confirmed by upregulation of IRE-1α, GRP78 and CHOP expression. PTX treatment also resulted in an increase in intracellular calcium (Ca(2+)) level. Ca(2+) is the central player as blocking Ca(2+) by intracellular calcium chelator (BAPTA-AM) effectively inhibited the PTX induced ER stress response as well as autophagy. Moreover, silencing of CHOP also resulted in autophagy inhibition with a decrease in Atg5 expression. Collectively, PTX triggers ER stress response followed by induction of autophagy via involvement of Ca(2+)→CHOP→Atg5 signalling cascade. Interestingly, inhibition of intracellular calcium level by BAPTA-AM significantly increased PTX mediated cell death by augmenting intrinsic apoptotic pathway. Inhibition of autophagy by the ATG5 siRNA and pharmacological inhibitor, chloroquine also enhances PTX induced cell death. Taken together, our results clearly indicate that activation of ER stress response and autophagy provides resistance to PTX mediated apoptosis, and thus, interferes with the anticancer activity of PTX in human melanoma cells.

Joo H, Lee HJ, Shin EA, et al.
c-Jun N-terminal Kinase-Dependent Endoplasmic Reticulum Stress Pathway is Critically Involved in Arjunic Acid Induced Apoptosis in Non-Small Cell Lung Cancer Cells.
Phytother Res. 2016; 30(4):596-603 [PubMed] Related Publications
Though arjunic acid, a triterpene isolated from Terminalia arjuna, was known to have antioxidant, antiinflammatory, and cytotoxic effects, its underlying antitumor mechanism still remains unclear so far. Thus, in the present study, the molecular antitumor mechanism of arjunic acid was examined in A549 and H460 non-small cell lung cancer (NSCLC) cells. Arjunic acid exerted cytotoxicity by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) assay and significantly increased sub-G1 population in A549 and H460 cells by cell cycle analysis. Consistently, arjunic acid cleaved poly (ADP-ribose) polymerase (PARP), activated Bax, and phosphorylation of c-Jun N-terminal kinases (JNK), and also attenuated the expression of pro-caspase-3 and Bcl-2 in A549 and H460 cells. Furthermore, arjunic acid upregulated the expression of endoplasmic reticulum (ER) stress proteins such as IRE1 α, ATF4, p-eIF2α, and C/EBP homologous protein (CHOP) in A549 and H460 cells. Conversely, CHOP depletion attenuated the increase of sub-G1 population by arjunic acid, and also JNK inhibitor SP600125 blocked the cytotoxicity and upregulation of IRE1 α and CHOP induced by arjunic acid in A549 and H460 cells. Overall, our findings suggest that arjunic acid induces apoptosis in NSCLC cells via JNK mediated ER stress pathway as a potent chemotherapeutic agent for NSCLC.

Tang NY, Chueh FS, Yu CC, et al.
Benzyl isothiocyanate alters the gene expression with cell cycle regulation and cell death in human brain glioblastoma GBM 8401 cells.
Oncol Rep. 2016; 35(4):2089-96 [PubMed] Related Publications
Glioblastoma multiforme (GBM) is a highly malignant devastating brain tumor in adults. Benzyl isothiocyanate (BITC) is one of the isothiocyanates that have been shown to induce human cancer cell apoptosis and cell cycle arrest. Herein, the effect of BITC on cell viability and apoptotic cell death and the genetic levels of human brain glioblastoma GBM 8401 cells in vitro were investigated. We found that BITC induced cell morphological changes, decreased cell viability and the induction of cell apoptosis in GBM 8401 cells was time-dependent. cDNA microarray was used to examine the effects of BITC on GBM 8401 cells and we found that numerous genes associated with cell death and cell cycle regulation in GBM 8401 cells were altered after BITC treatment. The results show that expression of 317 genes was upregulated, and two genes were associated with DNA damage, the DNA-damage-inducible transcript 3 (DDIT3) was increased 3.66-fold and the growth arrest and DNA-damage-inducible α (GADD45A) was increased 2.34-fold. We also found that expression of 182 genes was downregulated and two genes were associated with receptor for cell responses to stimuli, the EGF containing fibulin-like extracellular matrix protein 1 (EFEMP1) was inhibited 2.01-fold and the TNF receptor-associated protein 1 (TRAP1) was inhibited 2.08-fold. BITC inhibited seven mitochondria ribosomal genes, the mitochondrial ribosomal protein; tumor protein D52 (MRPS28) was inhibited 2.06-fold, the mitochondria ribosomal protein S2 (MRPS2) decreased 2.07-fold, the mitochondria ribosomal protein L23 (MRPL23) decreased 2.08-fold, the mitochondria ribosomal protein S2 (MRPS2) decreased 2.07-fold, the mitochondria ribosomal protein S12 (MRPS12) decreased 2.08-fold, the mitochondria ribosomal protein L12 (MRPL12) decreased 2.25-fold and the mitochondria ribosomal protein S34 (MRPS34) was decreased 2.30-fold in GBM 8401 cells. These changes of gene expression can provide the effects of BITC on the genetic level and are potential biomarkers for glioblastoma therapy.

Zhang B, Han H, Fu S, et al.
Dehydroeffusol inhibits gastric cancer cell growth and tumorigenicity by selectively inducing tumor-suppressive endoplasmic reticulum stress and a moderate apoptosis.
Biochem Pharmacol. 2016; 104:8-18 [PubMed] Related Publications
Gastric cancer is ranked as the third leading cause of cancer-related death in the world. Although extensive efforts have been made in recent decades to treat gastric cancer with various anticancer drugs, effective anti-gastric cancer therapeutics to cure the disease are still lacking in the clinics. Therefore, potent novel anti-gastric cancer drugs are greatly needed. In this study, we explored a novel anti-gastric cancer agent from a medicinal herb named Juncus effusus and found that the active component dehydroeffusol (DHE), a small molecular phenanthrene, effectively inhibited gastric cancer cell proliferation and tumorigenesis by inducing tumor suppressive endoplasmic reticulum (ER) stress and by triggering moderate apoptosis. Mechanistic studies revealed that DHE selectively activated the intracellular tumor suppressive stress response by promoting the overexpression of the key ER stress marker DNA damage-inducible transcript 3 (DDIT3), through upregulation of activating transcription factor 4 (ATF4). Concurrently, DHE suppressed the expression of the cell survival and ER stress marker glucose regulated protein of molecular mass 78 (GRP78) via downregulation of the transcription factor ATF6. In addition, DHE markedly activated the stress response signaling pathway MEKK4-MKK3/6-p38-DDIT3, but significantly inhibited ERK signaling. Our data suggest that DHE inhibits gastric cancer cell growth and tumorigenicity through selectively inducing a robust tumor suppressive ER stress response and a moderate apoptosis response. Therefore, DHE may provide a novel drug candidate for further development of potential anti-gastric cancer therapeutics.

Lee da H, Jung Jung Y, Koh D, et al.
A synthetic chalcone, 2'-hydroxy-2,3,5'-trimethoxychalcone triggers unfolded protein response-mediated apoptosis in breast cancer cells.
Cancer Lett. 2016; 372(1):1-9 [PubMed] Related Publications
The primary aim of this study was to find novel chemopreventive agents effective against breast cancer. Endoplasmic reticulum (ER) stress can induce apoptosis through the unfolded protein response (UPR). 2'-Hydroxy-2,3,5'-trimethoxychalcone (DK143) is a synthetic flavonoid derivative. The present study provides evidence supporting the role of the UPR in mediating the apoptotic effect of DK143. Treatment with DK143 triggered apoptosis through the activation of the caspase pathway in MDA-MB-231 breast cancer cells without affecting viability of MCF10A non-transformed breast epithelial cells. Further analysis revealed that DK143 produced reactive oxygen species (ROS) in MDA-MB-231 cells, but not in MCF10A cells, and upregulated the expression of ER stress sensors, including GRP78/BiP, IRE1α, CHOP, and Bim in MDA-MB-231 cells. In addition, UPR-related transcription factors, XBP-1 and CHOP, were activated by DK143. Moreover, silencing of IRE1α or CHOP by corresponding siRNA molecules attenuated DK143-induced apoptosis. Furthermore, DK143 suppressed mouse tumor growth in vivo. These results demonstrate that promoting ER stress in breast cancer cells via UPR induction might be a promising strategy for developing new chemotherapeutic or chemopreventive agents for breast cancer.

Kim JH, Park SJ, Kim TS, et al.
Testosterone production by a Leydig tumor cell line is suppressed by hyperthermia-induced endoplasmic reticulum stress in mice.
Life Sci. 2016; 146:184-91 [PubMed] Related Publications
AIMS: Leydig cells are characterized by their ability to produce testosterone. When the Leydig cells are unable to produce enough testosterone, spermatogenesis fails completely. Considering this, it is of great interest to investigate whether the expressions of steroidogenic enzymes are affected by testicular heat stress. This study aimed to demonstrate that heat induced ER-stress significantly influences steroidogenic enzyme expression and testosterone production in the Leydig cells.
MAIN METHODS: C57BL/6 mice were subjected to repetitive testicular heat-treatment at 42 °C for 15 min per day, and heat-treated mLTC-1 cells following hCG treatment for 1h. The protein and RNA expressions were measured by Western blot, RT-PCR. The testosterone and progesterone levels were detected by EIA. The histological and pathological characteristics using hematoxylin and eosin (H&E) and antibody stains.
KEY FINDINGS: The 3β-HSD expression was decreased by heat-stress and hCG treatment. While the GRP78/BiP and CHOP levels were increased by ER-stress inducers, those of the steroidogenic enzyme and progesterone were decreased. In contrast, an ER-stress inhibitor rescued the testosterone levels, even under heat-stress conditions. Moreover, the Leydig cells were randomly scattered, and severely damaged upon repetitive testicular heat-treatment. Additionally, immunohistochemical analyses revealed that cleaved caspase-3 was elevated in the testicular Leydig cells, and rescued by TUDCA. Thus, repetitive testicular heat-treatment in mice promotes excessive ER-stress, thereby leading to apoptosis of the Leydig cells and thus, decreased testosterone production.
SIGNIFICANCE: Our findings help to provide an ER-stress mediate mechanistic explanation to the impairment of spermatogenesis upon elevation of the testicular temperature.

Gwak H, Kim S, Dhanasekaran DN, Song YS
Resveratrol triggers ER stress-mediated apoptosis by disrupting N-linked glycosylation of proteins in ovarian cancer cells.
Cancer Lett. 2016; 371(2):347-53 [PubMed] Related Publications
Malignant tumors have a high glucose demand and alter cellular metabolism to survive. Herein, focusing on the utility of glucose metabolism as a therapeutic target, we found that resveratrol induced endoplasmic reticulum (ER) stress-mediated apoptosis by interrupting protein glycosylation in a cancer-specific manner. Our results indicated that resveratrol suppressed the hexosamine biosynthetic pathway and interrupted protein glycosylation through GSK3β activation. Application of either biochemical intermediates of the hexosamine pathway or small molecular inhibitors of GSK3β reversed the effects of resveratrol on the disruption of protein glycosylation. Additionally, an ER UDPase, ectonucleoside triphosphate diphosphohydrolase 5 (ENTPD5), modulated protein glycosylation by Akt attenuation in response to resveratrol. By inhibition or overexpression of Akt functions, we confirmed that the glycosylation activities were dependent on ENTPD5 expression and regulated by the action of Akt in ovarian cancer cells. Resveratrol-mediated disruption of protein glycosylation induced cellular apoptosis as indicated by the up-regulation of GADD153, followed by the activation of ER-stress sensors (PERK and ATF6α). Thus, our results provide novel insight into cancer cell metabolism and protein glycosylation as a therapeutic target for cancers.

Fang Q, Cai C, Chen H
[Application value of fine needle aspiration and cell block in preoperative diagnosis of thyroid cancer and discrimination of follicular tumor].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi. 2015; 50(8):668-72 [PubMed] Related Publications
OBJECTIVE: To study the application value of fine needle aspiration and cell block combined with molecular markers in early diagnosis of thyroid cancer and discriminate follicular tumor before operation.
METHODS: Fine needle biopsy of thyroid nodules was guided by color ultrasound, then the sample acquired was used to make smear and the rest to make cell block. The pathological diagnosis on smear, cell block or combination of both was made respectively. Then, the Envision immunohistochemical method was employed to detect the expressions of CK19, Galectin-3 in cell block samples, which had been used for the diagnosis of papillary thyroid carcinoma or thyroid nodules from benign lesions after operation and to detect the expressions of DDIT3, ki-67 of cell block that had been used for the diagnosis of follicular tumor nodules.
RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of cytopathology for the diagnosis of malignancy were 95.3%, 94.7%, 92.7%, 96.6% and 95.0% respectively; and the sensitivity, specificity and accuracy of the diagnosis used cell block alone or combined with smear were 88.1%, 95.3%, 92.3% and 95.3%, 94.7%, 95.0% respectively, which were higher than 53.8%, 83.7%, 71.3% from smear correspondingly. The positive expression rate of CK19 and Galectin-3 of papillary thyroid carcinoma cell block were 100% and 98.0% respectively, higher than the value 17.7% and 23.3% of thyroid benign lesions (P < 0.01); the positive expression rate of DDIT3 of thyroid follicular cancer cell block was 84.6%, higher than the value 35.1% of follicular adenoma (P < 0.01), there was no statistical significance of Positive expression rate of Ki-67 between thyroid follicular carcinoma and follicular adenoma cell block (P > 0.05).
CONCLUSIONS: It was conducive to early diagnose thyroid cancer with detection of CK19, Galection-3 of cell block made by ultrasound-guided fine needle biopsy of thyroid nodules. And it was also significant for DDIT3 detection to early discriminate follicular neoplasm before operation.

Huggins CJ, Mayekar MK, Martin N, et al.
C/EBPγ Is a Critical Regulator of Cellular Stress Response Networks through Heterodimerization with ATF4.
Mol Cell Biol. 2015; 36(5):693-713 [PubMed] Free Access to Full Article Related Publications
The integrated stress response (ISR) controls cellular adaptations to nutrient deprivation, redox imbalances, and endoplasmic reticulum (ER) stress. ISR genes are upregulated in stressed cells, primarily by the bZIP transcription factor ATF4 through its recruitment to cis-regulatory C/EBP:ATF response elements (CAREs) together with a dimeric partner of uncertain identity. Here, we show that C/EBPγ:ATF4 heterodimers, but not C/EBPβ:ATF4 dimers, are the predominant CARE-binding species in stressed cells. C/EBPγ and ATF4 associate with genomic CAREs in a mutually dependent manner and coregulate many ISR genes. In contrast, the C/EBP family members C/EBPβ and C/EBP homologous protein (CHOP) were largely dispensable for induction of stress genes. Cebpg(-/-) mouse embryonic fibroblasts (MEFs) proliferate poorly and exhibit oxidative stress due to reduced glutathione levels and impaired expression of several glutathione biosynthesis pathway genes. Cebpg(-/-) mice (C57BL/6 background) display reduced body size and microphthalmia, similar to ATF4-null animals. In addition, C/EBPγ-deficient newborns die from atelectasis and respiratory failure, which can be mitigated by in utero exposure to the antioxidant, N-acetyl-cysteine. Cebpg(-/-) mice on a mixed strain background showed improved viability but, upon aging, developed significantly fewer malignant solid tumors than WT animals. Our findings identify C/EBPγ as a novel antioxidant regulator and an obligatory ATF4 partner that controls redox homeostasis in normal and cancerous cells.

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