scholarly journals Betaglycan Alters NFκB-TGFβ2 Cross Talk to Reduce Survival of Human Granulosa Tumor Cells

2013 ◽  
Vol 27 (3) ◽  
pp. 466-479 ◽  
Author(s):  
Maree Bilandzic ◽  
Simon Chu ◽  
Yao Wang ◽  
Han L. Tan ◽  
Peter J. Fuller ◽  
...  

Abstract The molecular pathways controlling granulosa cell tumor (GCT) survival are poorly understood. In many cell types, nuclear factor-κB (NFκB) and TGFβ coordinately regulate cell survival to maintain tissue homeostasis. Because GCT cell lines exhibit constitutively activated NFκB, we hypothesized that NFκB blocks TGFβ-mediated cell death in GCT cells. To test this hypothesis, we used the human GCT cell line KGN, which exhibits loss of betaglycan, a TGFβ co-receptor. After inhibition of NFκB in KGN cells, re-expression of betaglycan resulted in a decrease in cell viability, which was further decreased by TGFβ2. Intriguingly, TGFβ2 increased NFκB reporter activity in control cells, but betaglycan expression suppressed both basal and TGFβ2-stimulated NFκB activity. Chemical inhibition of Mothers against decapentaplegic homolog 2/3 (SMAD2/3) signaling or SMAD2/3 gene silencing revealed that both SMADs contributed to cell survival. Furthermore, inhibiting NFκB activity resulted in a specific reduction in SMAD3 expression. Conversely, overexpression of SMAD3 increased basal NFκB activity and countered betaglycan-mediated suppression of NFκB activity. Finally, ERK1/2 activation emerged as the point of convergence of NFκB, SMAD3, and TGFβ2/betaglycan governance of GCT cell viability. Key findings in KGN cells were reproduced in a second GCT cell line, COV434. Collectively, our data establish that both SMAD2/3 and NFκB signaling pathways support GCT cell viability and suggest the existence of a positive feedback loop between NFκB and SMAD3 signaling in late-stage GCT. Furthermore, our data suggest that loss of betaglycan during tumor progression in GCT alters the functional outcomes generated by NFκB and TGFβ pathway cross talk.

2020 ◽  
Vol 74 (5) ◽  
pp. 553-562
Author(s):  
Kshama Pansare ◽  
Saurav Raj Singh ◽  
Venkatavaradhan Chakravarthy ◽  
Neha Gupta ◽  
Arti Hole ◽  
...  

Resistance to radiotherapy has been an impediment in the treatment of cancer, and the inability to detect it at an early stage further exacerbates the prognosis. We have assessed the feasibility of Raman spectroscopy as a rapid assay for predicting radiosensitivity of cancer cells in comparison to the conventional biological assays. Cell lines derived from breast adenocarcinoma (MCF7), gingivobuccal squamous cell carcinoma (ITOC-03), and human embryonic kidney (HEK293) were subjected to varying doses of ionizing radiation. Cell viability of irradiated cells was assessed at different time points using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and Raman spectroscopy, and colony-forming capability was evaluated by clonogenic assay. Radiosensitivity observed using MTT assay was limited by the finding of similar cell viability in all the three cell lines 24 h post-irradiation. However, cell survival assessed using clonogenic assay and principal component linear discriminant analysis (PC-LDA) classification of Raman spectra showed correlating patterns. Irradiated cells showed loss of nucleic acid features and enhancement of 750 cm−1 peak probably attributing to resonance Raman band of cytochromes in all three cell lines. PC-LDA analysis affirmed MCF7 to be a radioresistant cell line as compared to ITOC-03 and HEK293 to be the most radiosensitive cell line. Raman spectroscopy is shown to be a rapid and alternative assay for identification of radiosensitivity as compared to the gold standard clonogenic assay.


2003 ◽  
Vol 31 (1) ◽  
pp. 50-55 ◽  
Author(s):  
A. Hidalgo

Axons navigate to trace stereotypic trajectories over an environment often rich in glial cells. Once axonal trajectories are defined, their structuring proceeds through multiple fasciculation and defasciculation events, to finally establish the mature bundles. Fasciculation and ensheathment also proceed in close association between axons and glial cells, and ultimately require glia. The cross-talk between axons and glia during axon guidance is manifested in: (i) axonal fasciculation and bundling, promoted by glia; (ii) growth cone guidance, as glia function as guidepost cells at choice points; (iii) glial migration patterns, which are influenced by neurons; (iv) cell survival control, which constrains position and number of both cell types; and (iv) connectivity, where an axon contacts its final target aided by glial cells. Understanding the reciprocal interactions between neurons and glia during guidance and fasciculation is absolutely necessary to implement repair of axonal trajectories upon damage. Drosophila can be used as a model system for these purposes.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4230-4230
Author(s):  
Kodetthoor B. Udupa ◽  
Chhanda Bose

Abstract Erythropoietin (EPO) regulates the proliferation and differentiation of erythroid progenitors via its receptor, EPO-R and through various Mitogen activated protein kinase (MAPK) pathways. The role of EPO on other cell types is still unkown. In the present study we have elected to examine this aspect in a transformed pancreatic cell line, AR42J cells. We investigated the activation of two MAPKs, namely extracellular regulated kinase (ERK) and c-jun NH2-terminal kinase (JNK) after exposure of AR42J cells to 1 U/ml EPO using the Western blot analysis. We also examined cell viability during EPO exposure by high sensitivity fluoremetric method using CCK8. We found a rapid activation of ERK-1/2 in AR42J cells reaching the maximum of 3.3 fold in 5 min, while it took 30 min for JNK-1/2 to reach the maximum. In the absence of EPO, addition of specific JNK inhibitor, SP600125, reduced cell viability to 50% at a dose of 20 μM while with ERK inhibitor, UO126, cell viability was not reduced even up to 60 μM of the drug. To examine the effect of induction of MAPK by EPO on AR42J cell survival, cells were treated with inhibitors to ERK or JNK 1h prior to EPO addition and the cumulative cell survival were calculated from day 1 through 4. EPO addition to AR42J cells resulted in significantly higher cumulative cell survival of 1.00 ± 0.04 unit absorption compared to the value of 0.35 ± 0.02 unit absorption seen in controls without EPO. When cells were treated with EPO and ERK inhibitor a significantly higher cumulative cell survival of 1.50 ± 0.04 unit absorption was observed (p < 0.01) indicating ERK to be less effective in their survival. On the other hand, samples treated with EPO and JNK inhibitor had significantly lower cell survival (0.55 ± 0.06 unit absorption, p < 0.01) than the EPO control indicating an essential role of JNK in their survival. These results indicate that in EPO mediated survival of AR42J cells, activation of JNK appears to be more important than ERK activation thus indicating a key role of JNK in cell viability. It is very important to understand the role of EPO signaling in the viability of transformed cells since EPO is often supplemented after bone marrow transplantation to enhance the recovery after chemotherapy.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3110-3110
Author(s):  
Stamatia Laidou ◽  
Stavroula Ntoufa ◽  
Sofia Papanikolaou ◽  
Konstantia Kotta ◽  
Maria Koutroumani ◽  
...  

Abstract Recent evidence indicates that TAp63, the prevalent isoform of TP63 in Chronic Lymphocytic Leukemia (CLL), is implicated in disease pathogenesis. In CLL, TAp63 expression, modulated by both immune signaling and epigenetic modifications, promotes leukemic cell survival and homing to the bone marrow. In activated normal B cells, the TAp63 transcription factor binds the BCL2 gene, participating in an anti-apoptotic pathway (axis NF-κB/TAp63/BCL2) augmenting cell survival. In this study, we investigated the expression of TAp63 in a large cohort of CLL cases and its potential fluctuation during disease progression. Additionally, in order to further understand the pro-survival role of TAp63 in CLL, we interrogated at the molecular level the interplay betweenΤAp63 and BCL2. Initially, using RT-qPCR we quantified TAp63 mRNA expression in 166 CLL patients, consisting of 89 with unmutated IGHV genes (U-CLL) and 77 with mutated IGHV genes (M-CLL), prior to administration of treatment. Significantly higher TAp63 mRNA levels were observed in U-CLL vs M-CLL (FD=13.83, p<0.0001). However, outliers were identified in both subgroups, prompting us to re-classify all cases into TAp63high and TAp63low subgroups using ROC curve and Youden index statistical procedures. TAp63high patients displayed significantly shorter time-to-first-treatment (TTFT) (TAp63highmedian TTFT: 1.58 years; TAp63lowmedian TTFT: 4.07 years; p=0.03) and shorter overall survival (OS) (TAp63highmedian OS: 7.825 years; TAp63lowmedian OS: not yet reached; p=0.046). Next, we analyzed TAp63 mRNA expression in longitudinal samples of 25 U-CLL cases treated with either FCR or rituximab-chlorambucil. In each case, samples were collected at three 'landmarks'; diagnosis, first progressionand first relapse. Expression analysis by RT-qPCR showed that TAp63 levels significantly increased at disease relapse compared to diagnosis (FD=3.47, p=0.02). We subsequently investigated links between TAp63 and BCL2 by measuring BCL2 mRNA levels in 56 U-CLL cases from the present cohort and found statistically significant correlation with the corresponding TAp63 mRNA levels (spearman rho=0.31, p=0.01). To validate this observation, we undertook functional studies in the MEC1 CLL cell line. Considering that MEC1 cells express high TAp63 mRNA levels, we generated a stable MEC1 cell line to inducibly downregulate TAp63, using CRISPR/dCas9-KRAB upon treatment with doxycycline (Dox). We used 2 different guide RNAs (sgRNAs; sgRNA1, sgRNA2) targeting 2 distinct regions of the endogenous TAp63 promoter. After 5 days of induction, the expression levels of both TAp63 and BCL2 were quantified by one step RT-qPCR in Tet-on-dCas9-KRAB-sgRNA-TAp63 MEC1 cells. Inducible downregulation of TAp63 expression (gRNA1: FD=1.7, gRNA2: FD=1.53) resulted in downregulation of BCL2 expression (gRNA1: FD=1.34, gRNA2: FD=1.12) with strong correlation (rho=0.97, p<0.0001) between TP63 and BCL2 mRNA levels. Furthermore, we also observed correlation between TAp63 and BCL2 protein expression in primary cells of one representative TP63high CLL case (rho=0.94, p=0.01), in which TAp63 was silenced by RNA interference (RNAi) with 3 different siRNAs. Prompted by these results, we additionally assessed ex vivo the effect of the BCL2 inhibitor Venetoclax in primary CLL cells of both TAp63high (n=8) and TAp63low (n=6) cases. Cell viability was measured by flow cytometry at 24 and 48 hours after treatment. TAp63high cases were more resistant to treatment with Venetoclax as they showed no statistically significant reduction in cell viability compared to the respective (DMSO-treated) controls, in contrast to TAp63low cases (24h: FD=3.63, p=0.004; 48h: FD=7.17, p=0.005). In conclusion, we provide evidence suggesting that up-regulated TAp63 expression represents a novel resistance mechanism to chemoimmunotherapy in CLL. The pro-survival role of TAp63 is supported by its strong association with BCL2. Indeed, based on the present findings, TAp63 appears to act as a positive modulator of BCL2 in CLL cells, rendering them less responsive to apoptosis induction with the BCL2 inhibitor Venetoclax. Disclosures Hadzidimitriou: Abbvie: Research Funding; Gilead: Research Funding; Janssen: Honoraria, Research Funding. Stamatopoulos:Abbvie: Honoraria, Research Funding; Gilead: Honoraria, Research Funding; Janssen: Honoraria, Research Funding.


Proteomes ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 44 ◽  
Author(s):  
Sabrina Samuel ◽  
Alistair Marsden ◽  
Srihari Deepak ◽  
Francisco Rivero ◽  
John Greenman ◽  
...  

Glioblastomas (GBM) are the most common grade 4 brain tumours; patients have very poor prognosis with an average survival of 15 months after diagnosis. Novel research lines have begun to explore aberrant protein arginine methylation (ArgMe) as a possible therapeutic target in GBM and ArgMe inhibitors are currently in clinical trials. Enzymes known as protein arginine methyltransferases (PRMT1-9) can lead to mono- or di-ArgMe, and in the latter case symmetric or asymmetric dimethylation (SDMA and ADMA, respectively). Using the most common GBM cell line, we have profiled the expression of PRMTs, used ArgMe inhibitors as tools to investigate post-translational modifications cross-talk and measured the effect of ArgMe inhibitors on cell viability. We have identified novel SDMA events upon inhibition of ADMA in GBM cells and spheroids. We have observed cross-talk between ADMA and lysine acetylation in GBM cells and platelets. Treatment of GBM cells with furamidine, a PRMT1 inhibitor, reduces cell viability in 2D and 3D models. These data provide new molecular understanding of a disease with unmet clinical needs.


Author(s):  
Sylvie Polak-Charcon ◽  
Mehrdad Hekmati ◽  
Yehuda Ben Shaul

The epithelium of normal human colon mucosa “in vivo” exhibits a gradual pattern of differentiation as undifferentiated stem cells from the base of the crypt of “lieberkuhn” rapidly divide, differentiate and migrate toward the free surface. The major differentiated cell type of the intestine observed are: absorptive cells displaying brush border, goblet cells containing mucous granules, Paneth and endocrine cells containing dense secretory granules. These different cell types are also found in the intestine of the 13-14 week old embryo.We present here morphological evidence showing that HT29, an adenocarcinoma of the human colon cell line, can differentiate into various cell types by changing the growth and culture conditions and mimic morphological changes found during development of the intestine in the human embryo.HT29 cells grown in tissue-culture dishes in DMEM and 10% FCS form at late confluence a multilayer of morphologically undifferentiated cell culture covered with irregular microvilli, and devoid of tight junctions (Figs 1-3).


Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1198
Author(s):  
Juliana Gomez ◽  
Zammam Areeb ◽  
Sarah F. Stuart ◽  
Hong P. T. Nguyen ◽  
Lucia Paradiso ◽  
...  

Reticulocalbin 1 (RCN1) is an endoplasmic reticulum (ER)-residing protein, involved in promoting cell survival during pathophysiological conditions that lead to ER stress. However, the key upstream receptor tyrosine kinase that regulates RCN1 expression and its potential role in cell survival in the glioblastoma setting have not been determined. Here, we demonstrate that RCN1 expression significantly correlates with poor glioblastoma patient survival. We also demonstrate that glioblastoma cells with expression of EGFRvIII receptor also have high RCN1 expression. Over-expression of wildtype EGFR also correlated with high RCN1 expression, suggesting that EGFR and EGFRvIII regulate RCN1 expression. Importantly, cells that expressed EGFRvIII and subsequently showed high RCN1 expression displayed greater cell viability under ER stress compared to EGFRvIII negative glioblastoma cells. Consistently, we also demonstrated that RCN1 knockdown reduced cell viability and exogenous introduction of RCN1 enhanced cell viability following induction of ER stress. Mechanistically, we demonstrate that the EGFRvIII-RCN1-driven increase in cell survival is due to the inactivation of the ER stress markers ATF4 and ATF6, maintained expression of the anti-apoptotic protein Bcl-2 and reduced activity of caspase 3/7. Our current findings identify that EGFRvIII regulates RCN1 expression and that this novel association promotes cell survival in glioblastoma cells during ER stress.


1986 ◽  
Vol 103 (6) ◽  
pp. 2411-2420 ◽  
Author(s):  
E F Plow ◽  
D E Freaney ◽  
J Plescia ◽  
L A Miles

The capacity of cells to interact with the plasminogen activator, urokinase, and the zymogen, plasminogen, was assessed using the promyeloid leukemic U937 cell line and the diploid fetal lung GM1380 fibroblast cell line. Urokinase bound to both cell lines in a time-dependent, specific, and saturable manner (Kd = 0.8-2.0 nM). An active catalytic site was not required for urokinase binding to the cells, and 55,000-mol-wt urokinase was selectively recognized. Plasminogen also bound to the two cell lines in a specific and saturable manner. This interaction occurred with a Kd of 0.8-0.9 microM and was of very high capacity (1.6-3.1 X 10(7) molecules bound/cell). The interaction of plasminogen with both cell types was partially sensitive to trypsinization of the cells and required an unoccupied high affinity lysine-binding site in the ligand. When plasminogen was added to the GM1380 cells, a line with high intrinsic plasminogen activator activity, the bound ligand was comprised of both plasminogen and plasmin. Urokinase, in catalytically active or inactive form, enhanced plasminogen binding to the two cell lines by 1.4-3.3-fold. Plasmin was the predominant form of the bound ligand when active urokinase was added, and preformed plasmin can also bind directly to the cells. Plasmin on the cell surface was also protected from its primary inhibitor, alpha 2-antiplasmin. These results indicate that the two cell lines possess specific binding sites for plasminogen and urokinase, and a family of widely distributed cellular receptors for these components may be considered. Endogenous or exogenous plasminogen activators can generate plasmin on cell surfaces, and such activation may provide a mechanism for arming cell surfaces with the broad proteolytic activity of this enzyme.


1991 ◽  
Vol 273 (1) ◽  
pp. 153-160 ◽  
Author(s):  
J F Coquil ◽  
B Berthon ◽  
N Chomiki ◽  
L Combettes ◽  
P Jourdon ◽  
...  

The monohydroxy bile acid taurolithocholate permeabilizes the endoplasmic reticulum to Ca2+ in rat liver cells. To assess whether this action on the endoplasmic reticulum was restricted to this tissue, the effects of bile acid were investigated in two cell types quite unrelated to rat hepatocyte, namely human platelets and neuronal NG108-15 cell line. The results showed that taurolithocholate (3-100 microM) had no effect on free cytosolic [Ca2+] in human platelets and NG108-15 cells. whereas it increased it from 180 to 520 nM in rat hepatocytes. In contrast, in cells permeabilized by saponin, taurolithocholate initiated a profound release of the stored Ca2+ from the internal Ca2+ pools in the three cell types. The bile acid released 90% of the Ca2+ pools, with rate constants of about 5 min-1 and half-maximal effects at 15-30 microM. The results also showed that, in contrast with liver cells, which displayed an influx of [14C]taurolithocholate of 2 nmol/min per mg, human platelets and the neuronal cell line appeared to be resistant to [14C]taurolithocholate uptake. The influx measured in these latter cells was about 100-fold lower than in rat liver cells. Taken together, these data suggest that human platelets and NG108-15 cells do not possess the transport system for concentrating monohydroxy bile acids into cells. However, they show that human platelets and neuronal NG108-15 possess, in common with liver cells, the intracellular system responsible for taurolithocholate-mediated Ca2+ release from internal stores.


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