Antisense Long Non-Coding RNA in the LEF1 Locus Regulates Sense LEF1 Expression in Leukemic Cell Line KG1

Abstract Aberrant regulation of the WNT signaling pathway is a signature in numerous human cancers. Lymphoid enhancer-binding factor-1 (LEF1) is an important transcription factor downstream of this pathway. LEF1 over-expression induces AML in mice and plays a critical role in hematopoietic cell differentiation (Petropoulos et al JME 2008). Reduction of LEF1 expression through the progression of myelodysplastic syndrome has been reported and further supports the relevance of this gene in the disease pathogenesis (Pellagatti et al Br J Haematol. 2009). Our previous work using microarray technology revealed a decreased expression of a long non-coding RNA antisense to LEF1 (LEF1-AS) in MDS patients (Baratti et al BMC Medical Genomics 2010). Mounting evidence suggests that long non-coding transcripts play important roles in the epigenetic regulation of coding genes. In this context it is not surprising that long non-coding RNAs are emerging as key players in disease development and progression. Non-coding expression overlapping coding genes is very common and several examples of local regulation have been described in the literature. Here we investigate for the first time the role of LEF1 antisense long non-coding in hematopoiesis and demonstrated its contribution in the regulation of the LEF1 locus in a leukemic cell line. To explore a possible role of LEF1-AS in differentiation, we evaluated the expression pattern of LEF1-AS through erythroid cell differentiation using qRT-PCR. CD34+ HSC cells from 6 healthy donors were induced to differentiate into erythrocytes by addition of erythropoietin during 12 days. We observed that LEF1-AS is modulated during erythroid differentiation. It was significantly down-regulated during the first stages of differentiation from CD34+ HSC to erythroblast (from collection day 6 to day 8 after addition of erythropoietin, 78% mean reduction, P<0.0001) and it was up-regulated at the end-point of collection, day 12 (not significant). Lef1 coding gene displayed a similar expression pattern, consistent with previous reports of Lef1 expression during erythroid maturation (Edmaier et al Leukemia 2014). To explore a possible regulatory role of LEF1-AS, we cloned and over-expressed the transcript in KG1 CD34+ leukemia cell line. Transient over-expression of Lef1-AS led to a significant up-regulation of Lef1 gene (22% increase, P<0.05). We also observed an increase in cell viability (19% increase P<0.05), measured by MTT, which is consistent with the up-regulation of LEF1, a pro-proliferative and anti-apoptotic transcription factor. Our preliminary results from over-expressing LEF1-AS in CD34+ HSCs suggest a similar regulatory effect of LEF1-AS upon its coding counterpart, LEF1. Since aberrant expression of LEF1 is known to disrupt normal differentiation of CD34+ cells, LEF1-AS could potentially affect differentiation through the modulation of LEF1 coding gene. Our results reveal LEF1-AS transcript as a novel player in hematopoiesis and hematologic malignancy. Disclosures No relevant conflicts of interest to declare.

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Gene Expression Analysis of Bexarotene Differentiated Acute Myeloid Leukemias Identifies Known and Novel Gene Targets.

Blood ◽

10.1182/blood.v112.11.1199.1199 ◽

2008 ◽

Vol 112 (11) ◽

pp. 1199-1199

Author(s):

Patricia Vanessa Sanchez ◽

Reid P Bissonnette ◽

Donald E Tsai ◽

Martin Carroll

Keyword(s):

Transcription Factor ◽

Retinoic Acid ◽

Cell Differentiation ◽

Cell Lines ◽

Leukemic Cell ◽

Myeloid Differentiation ◽

Induced Differentiation ◽

Pparγ Agonist ◽

Acute Myeloid

Abstract Despite advances in understanding the molecular pathogenesis of acute myeloid leukemia (AML), therapy for relapsed disease remains inadequate with high mortalities. Clinicians at the University of Pennsylvania have demonstrated that the FDA approved retinoid X receptor (RXR) agonist bexarotene (Targretin™) stimulates leukemic cell differentiation in a subset patents with relapsed AML leading to clinical responses. This underscores the importance of identifying the mechanism by which bexarotene induces differentiation in AML in order to enhance the efficacy of this therapeutic approach. To understand the role of bexarotene and RXR receptors in leukemic cell differentiation, we initially utilized a pharmacogenetic approach to study the effects of bexarotene on AML cell lines using combinations of bexarotene with other differentiation induction agents. These studies demonstrate that bexarotene induces myeloid differentiation in MOLM14, HL60, THP-1, and NB4 cell lines but not in the myeloblastic cell line KG1a. Combination treatment of AML cell lines with bexarotene in combination with all trans retinoic acid (ATRA) enhanced differentiation suggesting that the mechanism of action for bexarotene is through RARα (retinoic acid receptor)/RXRα heterodimer stimulation. Consistent with this, differentiation induced by the drug combination was effectively blocked by the RAR antagonist, LG100815 and partially blocked by the RXR antagonist, LG101208. In contrast, bexarotene does not cooperate with valproic acid, theophylline, the PPARγ agonist rosiglitazone, or the LXR agonist T0901317. Preliminary data from quantitative RT-PCR and Affymetrix microarray analysis of bexarotene responsive AML cell lines at 3, 6, 12, and 96 hours post treatment has identified a subset of genes potentially regulated by bexarotene. CEBPε, a transcription factor known to play a critical role in granulopoiesis and PIM-1, a known oncogenic transcription factor, were among the genes that were significantly upregulated after bexarotene treatment of AML cells. Analysis of the functional role of C/EBPε in retinoid induced differentiation will be presented. Overall, this data supports the hypothesis that bexarotene, like ATRA, induces myeloid differentiation through activation of a RAR/RXR heterodimeric partner. However, other data suggests the presence of RAR independent pathways of signaling. LG100268, a pure RXR agonist induced myeloid differentiaton although not as robustly as bexarotene. Analysis of RAR and RXR mRNA expression in AML cell lines demonstrates that bexarotene does not induce expression of RARβ or p21, known targets induced by ATRA during myeloid differentiation. Chromatin immunoprecipitation assays demonstrate RXRα occupancy at RARβ and p21 promoter regions containing retinoid response elements (RARE). However, expression of these genes does not correlate with bexarotene-induced differentiation. This data suggests that although their expression has been linked to ATRA responsiveness, induction of RARβ and p21 expression is not necessary for retinoid induced myeloid differentiation. In summary, bexarotene induces myeloid differentiation through RAR dependent and independent pathways. Further analysis of the signaling events necessary for induction of myeloid differentiation by bexarotene may allow for improved selection of patients with AML who will respond to bexarotene.

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Anti-apoptotic Role of Focal Adhesion Kinase (FAK): Induction of Inhibitor-of-Apoptosis Proteins and Apoptosis Suppression by the Overexpression of FAK in a Human Leukemic Cell Line, HL-60

Biochemical Society Transactions ◽

10.1042/bst028a383a ◽

2000 ◽

Vol 28 (5) ◽

pp. A383-A383 ◽

Cited By ~ 1

Author(s):

Yoshiko Sonoda ◽

Yaeko Matsumoto ◽

Megumi Funakoshi ◽

Daisuke Yamamoto ◽

Steven K. Hanks ◽

...

Keyword(s):

Focal Adhesion Kinase ◽

Cell Line ◽

Focal Adhesion ◽

Leukemic Cell ◽

Inhibitor Of Apoptosis ◽

Inhibitor Of Apoptosis Proteins ◽

Leukemic Cell Line ◽

Human Leukemic Cell Line ◽

Apoptosis Proteins

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The role of transcription factor HNF1Α and long non-coding RNA HNF1Α-AS1 in the regulation of cytochrome P450s and nuclear receptors in liver cells

Drug Metabolism and Pharmacokinetics ◽

10.1016/j.dmpk.2017.11.120 ◽

2018 ◽

Vol 33 (1) ◽

pp. S32 ◽

Cited By ~ 1

Author(s):

Liming Chen ◽

Yifan Bao ◽

Stephanie Piekos ◽

Xiao-bo Zhong

Keyword(s):

Transcription Factor ◽

Nuclear Receptors ◽

Liver Cells ◽

Cytochrome P450s ◽

Non Coding Rna ◽

Long Non Coding Rna

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Non-coding RNA Activated by DNA Damage: Review of Its Roles in the Carcinogenesis

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.714787 ◽

2021 ◽

Vol 9 ◽

Author(s):

Soudeh Ghafouri-Fard ◽

Tahereh Azimi ◽

Bashdar Mahmud Hussen ◽

Atefe Abak ◽

Mohammad Taheri ◽

...

Keyword(s):

Dna Damage ◽

Clinical Outcome ◽

Cell Lines ◽

Genome Integrity ◽

Akt Pathway ◽

Poor Clinical Outcome ◽

Over Expression ◽

Non Coding Rna ◽

Long Non Coding Rna

Long intergenic non-coding RNA 00657 (LINC00657) or “non-coding RNA activated by DNA damage” (NORAD) is an extremely conserved and copious long non-coding RNA (lncRNA). This transcript has pivotal role in the preservation of genome integrity. Several researches have appraised the role of NORAD in the evolution of human cancers with most of them indicating an oncogenic role for this lncRNA. Several miRNAs such as miR-199a-3p, miR-608, miR−155−5p, miR-590-3p, miR-495-3p, miR-608, miR-202-5p, miR-125a-3p, miR-144-3p, miR−202−5p, and miR-30a-5p have been recognized as targets of NORAD in different cancer cell lines. In addition, NORAD has interactions with cancer-related pathways, particularly STAT, TGF-β, Akt/mTOR, and PI3K/AKT pathway. Over-expression of NORAD has been related with poor clinical outcome of patients with diverse types of neoplasms. Collectively, NORAD is a prospective marker and target for combating cancer.

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Role of Na+/H+ exchange in the granulocyte-macrophage colony-stimulating factor-dependent growth of a leukemic cell line

Journal of Cellular Physiology ◽

10.1002/jcp.1041430118 ◽

1990 ◽

Vol 143 (1) ◽

pp. 133-139 ◽

Cited By ~ 4

Author(s):

Daniele Caracciolo ◽

Antonella Pannocchia ◽

Silvia Treves ◽

Dario Ghigo ◽

Eugenio Gallo ◽

...

Keyword(s):

Cell Line ◽

Leukemic Cell ◽

Colony Stimulating Factor ◽

Leukemic Cell Line ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony ◽

Dependent Growth ◽

Stimulating Factor

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Cross-Resistance to Ionizing Radiation in a Murine Leukemic Cell Line Resistant tocis-Dichlorodiammineplatinum(II): Role of Ku Autoantigen

Molecular Pharmacology ◽

10.1124/mol.56.1.141 ◽

1999 ◽

Vol 56 (1) ◽

pp. 141-146 ◽

Cited By ~ 28

Author(s):

Philippe Frit ◽

Yvan Canitrot ◽

Catherine Muller ◽

Nicolas Foray ◽

Patrick Calsou ◽

...

Keyword(s):

Ionizing Radiation ◽

Cell Line ◽

Leukemic Cell ◽

Cross Resistance ◽

Leukemic Cell Line ◽

Ku Autoantigen ◽

Resistance To Ionizing Radiation

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Long non-coding RNA LINC00485 acts as a microRNA-195 sponge to regulate the chemotherapy sensitivity of lung adenocarcinoma cells to cisplatin by regulating CHEK1

Cancer Cell International ◽

10.1186/s12935-019-0934-7 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 6

Author(s):

Wei Zuo ◽

Wei Zhang ◽

Fei Xu ◽

Jing Zhou ◽

Wei Bai

Keyword(s):

Lung Adenocarcinoma ◽

Protein Coding ◽

Chemotherapy Sensitivity ◽

Over Expression ◽

Non Coding Rna ◽

Adenocarcinoma Cells ◽

Non Coding Rnas ◽

Long Non Coding Rna ◽

Competitive Endogenous Rna

Abstract Background Long non-coding RNAs (lncRNAs) are a family of non-protein-coding RNAs, which have the ability to influence the chemo-resistance of lung adenocarcinoma (LAC). In this study, we explored the mechanism by which LINC00485 competitively binds to microRNA-195 (miR-195) in the regulation of the chemotherapy sensitivity in LAC by regulating checkpoint kinase 1 (CHEK1). Methods Microarray analysis was used to screen out LAC related genes, and interaction between CHEK1 and miR-195, as well as that between miR-195 and LINC00485, was further confirmed by RNA-pull down and RIP. LINC00485 expression in LAC cells (A549 and H1299) was determined. The cells were then introduced with miR-195, anta-miR-195, LINC00485 or si-LINC00485 to identify the role of miR-195 and LINC00485 in LAC through evaluating the expression of CHEK1, CHEK1, Bax, Bcl-2, VEGF and HIF-1α in LAC cells by either RT-qPCR or Western blot analysis. After being treated with different concentration of cisplatin, cell proliferation, colony formation and apoptosis were assessed. Results LINC00485 acted as a competitive endogenous RNA against miR-195, and miR-195 directly targeted CHEK1. The expression of LINC00485 was higher in LAC cells. The down-regulation of LINC00485 or the up-regulation of miR-195 decreased the expression of CHEK1, Bcl-2, VEGF and HIF-1α, while also increasing the expression of Bax. Moreover, the over-expression of miR-195, or the silencing of LINC00485 enhanced the sensitivity of LAC cells to cisplatin, thereby promoting the apoptosis of LAC cells while suppressing the proliferation. Conclusion LINC00485 competitively binds to miR-195 to elevate CHEK1 expression in LAC cells, suggesting that LINC00485 is a novel direction for therapeutic strategies of LAC.

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