Multi-targeted gene silencing strategies inhibit replication of Canine morbillivirus

Abstract Background Canine morbilivirus (canine distemper virus, CDV) is a highly contagious pathogen associated with high morbidity and mortality in susceptible carnivores. Although there are CDV vaccines available, the disease poses a huge threat to dogs and wildlife hosts due to vaccine failures and lack of effective treatment. Thus, the development of therapeutics is an urgent need to achieve rapid outbreak control and reduce mortality in target species. Gene silencing by RNA interference has emerged as a promising therapeutic approach against different human and animal viruses. In this study, plasmid-based short hairpin RNAs (shRNAs) against three different regions in either CDV nucleoprotein (N), or large polymerase (L) genes and recombinant adenovirus-expressing N-specific multi-shRNAs were generated. Viral cytopathic effect, virus titration, plaque-forming unit reduction, and real-time quantitative RT-PCR analysis were used to check the efficiency of constructs against CDV. Results In CDV-infected VerodogSLAM cells, shRNA-expressing plasmids targeting the N gene markedly inhibited the CDV replication in a dose-dependent manner, with viral genomes and titers being decreased by over 99%. Transfection of plasmid-based shRNAs against the L gene displayed weaker inhibition of viral RNA level and virus yield as compared to CDV N shRNAs. A combination of shRNAs targeting three sites in the N gene considerably reduced CDV RNA and viral titers, but their effect was not synergistic. Recombinant adenovirus-expressing multiple shRNAs against CDV N gene achieved a highly efficient knockdown of CDV N mRNAs and successful inhibition of CDV replication. Conclusions We found that this strategy had strong silencing effects on CDV replication in vitro. Our findings indicate that the delivery of shRNAs using plasmid or adenovirus vectors potently inhibits CDV replication and provides a basis for the development of therapeutic strategies for clinical trials.

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Targeting a Lipid Desaturation Enzyme, SCD1, Selectively Eliminates Colon Cancer Stem Cells through the Suppression of Wnt and NOTCH Signaling

Cells ◽

10.3390/cells10010106 ◽

2021 ◽

Vol 10 (1) ◽

pp. 106

Author(s):

Yeongji Yu ◽

Hyejin Kim ◽

SeokGyeong Choi ◽

JinSuh Yu ◽

Joo Yeon Lee ◽

...

Keyword(s):

Colon Cancer ◽

Notch Signaling ◽

Cultured Cells ◽

Pcr Analysis ◽

Marker Genes ◽

Dependent Manner ◽

Lipid Desaturation ◽

Novel Target

The elimination of the cancer stem cell (CSC) population may be required to achieve better outcomes of cancer therapy. We evaluated stearoyl-CoA desaturase 1 (SCD1) as a novel target for CSC-selective elimination in colon cancer. CSCs expressed more SCD1 than bulk cultured cells (BCCs), and blocking SCD1 expression or function revealed an essential role for SCD1 in the survival of CSCs, but not BCCs. The CSC potential selectively decreased after treatment with the SCD1 inhibitor in vitro and in vivo. The CSC-selective suppression was mediated through the induction of apoptosis. The mechanism leading to selective CSC death was investigated by performing a quantitative RT-PCR analysis of 14 CSC-specific signaling and marker genes after 24 and 48 h of treatment with two concentrations of an inhibitor. The decrease in the expression of Notch1 and AXIN2 preceded changes in the expression of all other genes, at 24 h of treatment in a dose-dependent manner, followed by the downregulation of most Wnt- and NOTCH-signaling genes. Collectively, we showed that not only Wnt but also NOTCH signaling is a primary target of suppression by SCD1 inhibition in CSCs, suggesting the possibility of targeting SCD1 against colon cancer in clinical settings.

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METHYLTRANSFERASE SMYD5 EXAGGERATES INFLAMMATORY BOWEL DISEASE BY REGULATING PPAR-γ COACTIVATOR 1-α STABILITY

Inflammatory Bowel Diseases ◽

10.1093/ibd/izaa347.061 ◽

2021 ◽

Vol 27 (Supplement_1) ◽

pp. S27-S27

Author(s):

Yuning Hou ◽

Xiaonan Sun ◽

Pooneh Gheinani ◽

Xiaoqing Guan ◽

Shaligram Sharma ◽

...

Keyword(s):

Mitochondrial Biogenesis ◽

Experimental Colitis ◽

Conditional Knockout ◽

Peroxisome Proliferator ◽

Dependent Manner ◽

Lysine Methylation ◽

Promising Therapeutic Approach ◽

Mitochondrial Functions ◽

Inflammatory Bowel

Abstract Background and Aims The expression and role of methyltransferase SET and MYND domain-containing protein 5 (SMYD5) in inflammatory bowel diseases (IBD) is completely unknown. Here, we investigated the role and the underlying mechanism of epithelial SMYD5 in IBD pathogenesis and progression. Methods The expression and subcellular localization of SMYD5 and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) were examined by Western blot analysis, immunofluorescence staining, and immunohistochemistry in intestinal epithelial cells (IECs) and in colon tissues from human IBD patients and mice with experimental colitis. Mice with Smyd5 conditional knockout in IECs and littermate controls were subjected to DSS-induced experimental colitis and the disease severity and inflammation were assessed. SMYD5-regulated mitochondrial biogenesis was examined by RT-qPCR and transmission electron microscopy and mitochondrial oxygen consumption rate was measured in a Seahorse Analyzer system. The interaction between SMYD5 and PGC-1α was determined by co-immunoprecipitation assay. PGC-1α degradation and turnover (half-life) were analyzed by cycloheximide chase assay. SMYD5-mediated PGC-1α methylation was measured via in vitro methylation followed by mass spectrometry to identify the specific lysine residues that were methylated. Results Up-regulated SMYD5 and down-regulated PGC-1α were observed in IECs from IBD patients and mice with experimental colitis. However, Smyd5 depletion in IECs protected mice from DSS-induced colitis. SMYD5 was critically involved in regulating mitochondrial biology such as mitochondrial biogenesis, respiration, and apoptosis. Mechanistically, SMYD5 regulated mitochondrial functions in a PGC-1α dependent manner. Further, SMYD5 mediated lysine methylation of PGC-1α and facilitated its ubiquitination and proteasomal degradation. Conclusion SMYD5 attenuates mitochondrial functions in IECs and promotes IBD progression by enhancing the proteasome-mediated degradation of PGC-1α protein in a methylation-dependent manner. Strategies to decrease SMYD5 expression and/or increase PGC-1α expression in IECs might be a promising therapeutic approach to treat patients with IBD.

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Inhibition of Cellular Proteasome Activities Enhances Hepadnavirus Replication in an HBX-Dependent Manner

Journal of Virology ◽

10.1128/jvi.78.9.4566-4572.2004 ◽

2004 ◽

Vol 78 (9) ◽

pp. 4566-4572 ◽

Cited By ~ 67

Author(s):

Zhensheng Zhang ◽

Ulrike Protzer ◽

Zongyi Hu ◽

James Jacob ◽

T. Jake Liang

Keyword(s):

Recombinant Adenovirus ◽

Hepatitis Virus ◽

Proteasome Inhibitors ◽

Productive Infection ◽

Wild Type Virus ◽

Dependent Manner ◽

Type Virus ◽

Wild Type

ABSTRACT The X protein (HBX) of the hepatitis B virus (HBV) is not essential for the HBV life cycle in vitro but is important for productive infection in vivo. Our previous study suggests that interaction of HBX with the proteasome complex may underlie the pleiotropic functions of HBX. With the woodchuck model, we demonstrated that the X-deficient mutants of woodchuck hepatitis virus (WHV) are not completely replication defective, possibly behaving like attenuated viruses. In the present study, we analyzed the effects of the proteasome inhibitors on the replication of wild-type and X-negative HBV and WHV. Recombinant adenoviruses or baculoviruses expressing replicating HBV or WHV genomes have been developed as a robust and convenient system to study viral replication in tissue culture. In cells infected with either the recombinant adenovirus-HBV or baculovirus-WHV, the replication level of the X-negative construct was about 10% of that of the wild-type virus. In the presence of proteasome inhibitors, the replication of the wild-type virus was not affected, while the replication of the X-negative virus of either HBV or WHV was enhanced and restored to the wild-type level. Our data suggest that HBX affects hepadnavirus replication through a proteasome-dependent pathway.

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Interleukin-6 (IL-6), IL-1, receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin production by human osteoblastic cells: comparison of the effects of 17-beta oestradiol and raloxifene

Journal of Endocrinology ◽

10.1677/joe.0.1770423 ◽

2003 ◽

Vol 177 (3) ◽

pp. 423-433 ◽

Cited By ~ 62

Author(s):

J Cheung ◽

YT Mak ◽

S Papaioannou ◽

BA Evans ◽

I Fogelman ◽

...

Keyword(s):

Interleukin 6 ◽

In Vivo Studies ◽

Pcr Analysis ◽

Nuclear Factor Kappab ◽

Dependent Manner ◽

Nuclear Factor ◽

Treatment Change ◽

Rankl Mrna ◽

Receptor Activator

Oestrogen inhibits bone resorption, at least in part, by regulating the production of several cytokines, including interleukin-6 (IL-6), IL-1, receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG) by cells of the osteoblastic lineage. The selective oestrogen receptor modulator raloxifene (RAL) acts on bone in a similar manner to oestrogen, although the mechanisms of action of RAL on osteoblasts still remain unclear. We investigated and compared the effects of 17-beta oestradiol (E(2)) and RAL on the regulation of IL-6, IL-1, RANKL and OPG in vitro in primary human osteoblastic (HOB) cells and in an immortalised clonal human bone marrow stromal cell line (HCC1) with osteoblastic characteristics. We tested E(2) and RAL at concentrations ranging from 10(-12) to 10(-6) M. IL-6, IL-1alpha and IL-1beta, OPG and RANKL were measured by ELISA. RANKL and OPG mRNA steady state level was assessed by quantitative PCR analysis. Both E(2) and RAL led to a significant reduction in IL-6 production in the HOB cells, although the effect was more marked with E(2) (P<0.05). IL-1alpha and IL-1beta also decreased significantly following treatment with E(2) and RAL in the HCC1 cells (E(2) (10(-8), 10(-7) and 10(-6) M), % reduction (means+/-S.E.M.) compared with vehicle-treated cells - IL-1alpha: 84+/-7.4, 70.8+/-2.9*, 78.2+/-4.8*; IL-1beta: 79+/-10, 72.8+/-8.2*, 66.6+/-2.8*; RAL (10(-8), 10(-7) and 10(-6) M) - IL-1alpha: 72.4+/-5*, 79+/- 5.2*, 102+/-7.7; IL-1beta: 67.9+/-3.2*, 69+/-2.5*, 73.8+/- 6.2*; *P<0.05). OPG protein concentration decreased significantly in a dose-dependent manner following treatment with E(2) and RAL (% reduction E(2) (10(-8), 10(-7) and 10(-6) M) - HOB: 72.5+/-8.4*, 80+/-6.7*, 62.8+/-8.9*; HCC1: 109+/-4, 98.8+/-6, 54.5+/-3.4*; RAL (10(-8), 10(-7) and 10(-6) M) - HOB: 81.5+/-5.5*, 62.7+/-7.4*, 55.2+/-10.9*; HCC1: 92.7+/-7.4, 67+/-12.2*, 39+/-4.5*; *P<0.05). In the HCC1 cells, RANKL protein did not change significantly following E(2). In contrast, a significant reduction in RANKL was seen with RAL at 10(-7) and 10(-6) M (66+/-6.4% and 74+/-3% respectively). There was no change in OPG mRNA expression following E(2) or RAL in the HCC1 cells, although in the HOB cells we observed a significant reduction in OPG mRNA. RANKL mRNA decreased significantly in the HCC1 cells following RAL (10(-8), 10(-7)and 10(-6) M) treatment (% change from controls: 52+/-2*, 62+/-1*, 53+/-5.8*; *P<0.05). Similar results were seen in the HOB cells with RAL at 10(-6) M (RANKL mRNA: 72+/-5.5, P<0.05). In addition, there was a significant decrease in the RANKL/OPG ratio after RAL at 10(-6) M (HOB: 65.6+/-5*, HCC1: 56.9+/-20*; *P<0.05). RANKL/OPG ratio did not change significantly in the HCC1 cells following E(2). However, in contrast to RAL, we observed an increase in the RANKL/OPG ratio in the HOB cells following treatment with E(2). In conclusion, the study shows that RAL and E(2) have divergent cell-specific effects on the regulation of cytokines. The data also suggest that, in contrast to E(2), RAL may exert its anti-resorptive actions, at least in part, via the RANKL/OPG pathway. Further in vivo studies are required to confirm this.

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Recombinant Water Stress Protein 1 (Re-WSP1) Suppresses Colon Cancer Cell Growth Through Mir-539/Β-Catenin Signaling Pathway

10.21203/rs.3.rs-302966/v1 ◽

2021 ◽

Author(s):

Songjia Guo ◽

Shuhua Shan ◽

Haili Wu ◽

huiqiang hao ◽

Zhuoyu Li

Keyword(s):

Colon Cancer ◽

Water Stress ◽

Cell Growth ◽

Molecular Mechanisms ◽

Stress Protein ◽

Pcr Analysis ◽

Dependent Manner ◽

Nostoc Commune

Abstract Nostoc commune Vauch is a nitrogen-fixing blue-green algae, contains a large number of active molecules with medicinal functions. Our previous study found that a water stress protein (WSP1) from Nostoc commune Vauch and its the recombinant protein (Re-WSP1) exhibited significant anti-colon cancer (CRC) activity both in vitro and in vivo. However, the underlying mechanism remains unknown. In this study, the CCK8 and clonogenic assays showed that Re-WSP1 restrained the colon cancer growth in a dose-dependent manner. Mechanistically, Re-WSP1 inhibited the expression of β-catenin, which was partly reversed by LiCl treatment, demonstrating a key role in Re-WSP1-induced inhibition of cell growth. Quantitative PCR analysis showed that the expression of microRNA-539 (miR-539) was significantly up-regulated upon Re-WSP1 treatment. Moreover, miR-539 negatively regulateed the expression of β-catenin through directly binds to the 3’UTR of β-catenin mRNA. Taken together, our data demonstrate that Re-WSP1 suppresses the CRC growth via miR-539/β-catenin axis, which provides new insights into the molecular mechanisms underlying Re-WSP1 against CRC.

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Abstract 12880: Up-Regulation of Microrna-208b Contributes to Diabetic Myocardial Fibrosis in Mouse

Circulation ◽

10.1161/circ.130.suppl_2.12880 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Zhi Xin Shan ◽

Lin lin Guo ◽

Jie ning Zhu ◽

Qiu xiong Lin ◽

Chun yu Deng ◽

...

Keyword(s):

Myocardial Fibrosis ◽

Recombinant Adenovirus ◽

Cardiac Fibroblasts ◽

Transcriptional Level ◽

Dependent Manner ◽

Genes Expression ◽

Diabetic Myocardium

MicroRNAs play important roles in myocardial fibrosis during diabetic cardiomyopathy. The present study aimed to investigate the role of microRNA-208b (miR-208b) in diabetic myocardial fibrosis. Compared to the db/m control mice, Smad3 was activated , fibrosis-related genes expression were significantly up-regulated, and miRNAs were dysregulated in the myocardium of the 16-week-old diabetic db/db mice. miR-208b was confirmed up-regulated in the db/db diabetic myocardium in vivo and in mouse cardiomyocytes and cardiac fibroblasts after treatment with Ang-II, TGF-β and high glucose/glucose oxidase (HG/Go) in vitro , respectively. By using recombinant adenovirus expressing CD63-GFP, rAd-CD63-GFP, we infected neonatal mouse cardiomyocytes with rAd-CD63-GFP and tracked the secreted exosomes with GFP. We found that miR-208b was increased in the secreted exosomes from HG/Go-treated cardiomyocytes, and the exosomes with increased miR-208b could enhance fibrosis associated Col1a1, α-SMA and CTGF expressions in cardiac fibroblasts. Transfection of miR-208b mimic could increase Col1a1, α-SMA and CTGF expression in a dose-dependent manner in cardiac fibroblasts. However, blockage of miR-208b could inhibit fibrosis related genes expression. Mtf2 and Pgrmc1 were verified modulated by miR-208b at post transcriptional level in vitro . Consistently, Mtf2 and Pgrmc1 expressions were decreased in the diabetic myocardium, and knockdown of Mtf2 or Pgrmc1could increase fibrosis related genes expression in cardiac fibroblasts. Smad3 inhibitor, Naringenin, could dramatically inhibit miR-208b expression in cardiac fibroblasts. Taken together, we demonstrated that miR-208b was up-regulated in diabetic fibrotic myocardium, Mtf2 and Pgrmc1 mediated the effect of miR-208b on enhancing Col1a1, α-SMA and CTGF expression in diabetic myocardial fibrosis.

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Ubiquitin Carboxyl-Terminal Hydrolase L3 Promotes Insulin Signaling and Adipogenesis

Endocrinology ◽

10.1210/en.2009-0332 ◽

2009 ◽

Vol 150 (12) ◽

pp. 5230-5239 ◽

Cited By ~ 17

Author(s):

Mari Suzuki ◽

Rieko Setsuie ◽

Keiji Wada

Keyword(s):

Insulin Signaling ◽

Glycogen Synthase ◽

Ectopic Expression ◽

Hydrolase Activity ◽

Pcr Analysis ◽

Dependent Manner ◽

Wild Type ◽

Igf I ◽

Carboxyl Terminal

Abstract Insulin is a potent adipogenic hormone that triggers the induction of a series of transcription factors and specific proteins governing the differentiation of preadipocytes into mature adipocytes. Here we report that ubiquitin carboxyl-terminal hydrolase (UCH)-L3, a deubiquitinating enzyme, promotes insulin signaling and adipogenesis. Uchl3−/− mice had less visceral white adipose tissue compared with wild-type mice. In vitro adipogenesis experiments revealed that mouse embryonic fibroblasts (MEFs) and preadipocytes from Uchl3−/− mice had impaired ability to differentiate into mature adipocytes than those from wild-type mice. This difference was diminished by removing insulin from the medium. RT-PCR analysis showed that insulin-regulated expression of srebp1c, fas, glut4, and adiponectin is impaired in Uchl3−/− cells. The phosphorylation of insulin/IGF-I receptor, Akt, glycogen synthase kinase-3β, and FoxO1 was decreased in Uchl3−/− MEFs treated with insulin. Moreover, ectopic expression of wild-type UCH-L3 restored the phosphorylation of insulin/IGF-I receptor and adipocyte differentiation in Uchl3−/− MEFs. In contrast, hydrolase activity-deficient UCH-L3 did not enhance insulin signaling and the expression of glut4, fabp4, and adiponectin, resulting in impaired formation of large lipid droplets. These results suggest that UCH-L3 promotes adipogenesis by enhancing insulin signaling in a hydrolase activity-dependent manner.

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Resveratrol Suppresses Ovarian Cancer Cell Growth and Invasion Through Upregulation of microRNA-34a

10.21203/rs.3.rs-38233/v1 ◽

2020 ◽

Author(s):

Bing Wei ◽

Shangli Yao ◽

Ming Gao ◽

Zujun Wang ◽

Wenyan Wang ◽

...

Keyword(s):

Ovarian Cancer ◽

Cell Growth ◽

Molecular Mechanisms ◽

Pcr Analysis ◽

Dependent Manner ◽

Cancer Cell Growth ◽

Anti Cancer ◽

Underlying Mechanisms

Abstract Resveratrol (RES), a natural compound found in red wine, has previously reported to suppress ovarian cancer (OC) cell growth in vitro and in vivo; however, its potential molecular mechanisms are not fully elucidated. The aim of this study is to investigate the suppressive potential of RES in OC cell growth and invasion and reveal the underlying mechanisms. Herein, we found that RES treatment obviously suppressed the proliferative and invasive capacities of OC cells, and elevated cell apoptosis in vitro. Subsequent microarray and qRT-PCR analysis further showed that microRNA-34a (miR-34a) was significantly increased by RES treatment. Moreover, the inhibitory effects of RES on OC cells were enhanced by miR-34a overexpression, whereas weakened by miR-34a inhibition in OC cells. Of note, Bcl-2, an anti-apoptotic gene, was identified as a direct target of miR-34a. Then, we revealed that RES decreased the expression of Bcl-2 in OC cells in a dose dependent manner. Furthermore, the anti-tumor effects of RES were abolished by overexpression of Bcl-2 in OC cells. Overall, these results demonstrated that RES exerts the anti-cancer effects on OC cells through the miR-34a/Bcl-2 axis.

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Abstract 385: Tenascin-C Worsens Myocardial Inflammation and Fibrosis by Enhancing Macrophage Activation via NF-kappaB in Mouse Hypertensive Heart

Hypertension ◽

10.1161/hyp.62.suppl_1.a385 ◽

2013 ◽

Vol 62 (suppl_1) ◽

Author(s):

Naoshi Shimojo ◽

Ryotaro Hashizume ◽

Mari Hara ◽

Yuka Suzuki ◽

Tomohiro Nishioka ◽

...

Keyword(s):

Body Weight ◽

Macrophage Activation ◽

Weight Ratio ◽

Integrin Αvβ3 ◽

Heart Weight ◽

Pcr Analysis ◽

Dependent Manner ◽

Tenascin C ◽

Nf Kappab

Background and Aim: Tenascin-C (TN-C) is an extracellular matrix glycoprotein, not detected in normal adult heart but it expresses under various pathological conditions. We have previously reported in the enhanced TN-C production and accumulation of macrophages in the perivascular lesions of angiotensin II (AgII)-induced cardiac fibrosis mouse model. To clarify the role of TN-C in molecular mechanism, we analyzed the effect of TN-C in hypertensive heart utilizing wild-type (WT) and TN-C knock-out (TNKO) mice. Furthermore, to assess whether TN-C is involved in macrophage activation, we investigated in vitro study using macrophages isolated from the peritoneal cavity of WT mice. Methods and Results: Balb/c WT and TNKO mice were treated with 560 ng/kg body weight/min AgII subcutaneously by osmotic minipump for 4 weeks (WT/AgII and TNKO/AgII), and analyzed histological and molecular biological approaches. AgII treatment increased blood pressure, heart weight/body weight ratio, atrial and brain natriuretic peptide expression level and sizes of cardiomyocytes, but no significant differences were detected between WT/AgII and TNKO/AgII mice. In WT/AgII mice, interstitial collagen fibers (10.29±5.09% vs. WT: 4.6±1.56%, p<0.001) and accumulation of mac-3 positive macrophages (50±15.13 vs. WT: 6±2.55 cells/section, p<0.001) were observed at perivascular regions, and expression levels of interleukin (IL)-6 (1.85±0.39 fold, p<0.05) and monocyte chemoattractant protein (MCP)-1 (3.20±0.53 fold, p<0.001) were up-regulated. These changes were significantly reduced in TNKO/AgII mice. In vitro, TN-C accelerated macrophage migration in the presence of MCP-1. Western blotting and Immunofluorescence staining indicated that TN-C activated rapidly NF-kappaB. RT-PCR analysis demonstrated that TN-C up-regulated IL-6 mRNA on NF-kappaB dependent manner (39.90±18.10 fold, p<0.01). Integrin αVβ3 antagonist P11 suppressed these changes. Conclusion: The present study clearly demonstrated that TN-C aggravates inflammation and fibrosis in hypertensive heart by upregulation of IL-6 productions by activating NF-kappaB via integrin αVβ3 on macrophage.

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Targeting of survivin by nanoliposomal ceramide induces complete remission in a rat model of NK-LGL leukemia

Blood ◽

10.1182/blood-2010-02-271080 ◽

2010 ◽

Vol 116 (20) ◽

pp. 4192-4201 ◽

Cited By ~ 50

Author(s):

Xin Liu ◽

Lindsay Ryland ◽

Jun Yang ◽

Aijun Liao ◽

Cesar Aliaga ◽

...

Keyword(s):

Complete Remission ◽

Nk Cells ◽

Rat Model ◽

Dependent Manner ◽

Promising Therapeutic Approach ◽

C6 Ceramide ◽

Dose Dependent ◽

Lgl Leukemia

Abstract The natural killer (NK) type of aggressive large granular lymphocytic (LGL) leukemia is a fatal illness that pursues a rapid clinical course. There are no effective therapies for this illness, and pathogenetic mechanisms remain undefined. Here we report that the survivin was highly expressed in both aggressive and chronic leukemic NK cells but not in normal NK cells. In vitro treatment of human and rat NK-LGL leukemia cells with cell-permeable, short-chain C6-ceramide (C6) in nanoliposomal formulation led to caspase-dependent apoptosis and diminished survivin protein expression, in a time- and dose-dependent manner. Importantly, systemic intravenous delivery of nanoliposomal ceramide induced complete remission in the syngeneic Fischer F344 rat model of aggressive NK-LGL leukemia. Therapeutic efficacy was associated with decreased expression of survivin in vivo. These data suggest that in vivo targeting of survivin through delivery of nanoliposomal C6-ceramide may be a promising therapeutic approach for a fatal leukemia.

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