Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period

Background: Genetic mechanisms that result in the development and progression of B-cell chronic lymphocytic leukemia (B-CLL) are mainly unknown. We have analyzed gene expression patterns in Ukrainian B-CLL patients with the aim of identifying B-CLL involved / associated genes in order to shed light...

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Дата:2012
Автори: Savli, H., Sunnetci, D., Cine, N., Gluzman, D.F., Zavelevich, M.P., Sklyarenko, L.M., Nadgornaya, V.A., Koval, S.V.
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Опубліковано: Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України 2012
Назва видання:Experimental Oncology
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Цитувати:Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period / H. Savli, D. Sunnetci, N. Cine, D.F. Gluzman, M.P. Zavelevich, L.M. Sklyarenko, V.A. Nadgornaya, S.V. Koval // Experimental Oncology. — 2012. — Т. 34, № 1. — С. 57-63. — Бібліогр.: 47 назв. — англ.

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spelling irk-123456789-1387172018-06-20T03:06:16Z Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period Savli, H. Sunnetci, D. Cine, N. Gluzman, D.F. Zavelevich, M.P. Sklyarenko, L.M. Nadgornaya, V.A. Koval, S.V. Original contributions Background: Genetic mechanisms that result in the development and progression of B-cell chronic lymphocytic leukemia (B-CLL) are mainly unknown. We have analyzed gene expression patterns in Ukrainian B-CLL patients with the aim of identifying B-CLL involved / associated genes in order to shed light on the biology of this pathological entity. Material and methods: The samples of the peripheral blood and bone marrow of 44 Ukrainian B-CLL patients with no characteristics indicative of unfavorable course of the disease such as CD38 were analyzed morphologically and immunocytochemically according to the new WHO classification. Total RNA was isolated, and gene expression levels were determined by microarray method comparing with the sample from 17 healthy donors. Results: We investigated interactions using the Ingenuity Pathway Analysis (IPA) software and found 1191 network eligible up-regulated genes and 3398 Functions/Pathways eligible up-regulated genes, 1225 network eligible down-regulated genes and 2657 Functions/Pathways eligible down-regulated genes. Conclusion: In B-CLL patients, gene networks around MYC, HNF1A and HNF4A, YWHAG, NF-κB1 and SP1 are identified as up-regulated; CEBPA, YWHAG, SATB1 and RB1 — as down-regulated. G protein coupled receptor signaling, arachidonic acid and linoleic acid metabolisms, calcium signaling, metabolism of xenobiotics by cytochrome P450 are found out as significant up-regulated pathways. EIF2 and Cdc42 signaling, regulation of eIF4 and p70S6k signaling, protein ubiquitination pathway and oxidative phosphorylation are the most significant down-regulated pathways obtained in our study. The involvement of NF-κB gene network and upregulated levels of G protein coupled receptor signaling pathway, which has an important role in transcription of NF-κB, are important and need further examination. 2012 Article Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period / H. Savli, D. Sunnetci, N. Cine, D.F. Gluzman, M.P. Zavelevich, L.M. Sklyarenko, V.A. Nadgornaya, S.V. Koval // Experimental Oncology. — 2012. — Т. 34, № 1. — С. 57-63. — Бібліогр.: 47 назв. — англ. 1812-9269 http://dspace.nbuv.gov.ua/handle/123456789/138717 en Experimental Oncology Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
language English
topic Original contributions
Original contributions
spellingShingle Original contributions
Original contributions
Savli, H.
Sunnetci, D.
Cine, N.
Gluzman, D.F.
Zavelevich, M.P.
Sklyarenko, L.M.
Nadgornaya, V.A.
Koval, S.V.
Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period
Experimental Oncology
description Background: Genetic mechanisms that result in the development and progression of B-cell chronic lymphocytic leukemia (B-CLL) are mainly unknown. We have analyzed gene expression patterns in Ukrainian B-CLL patients with the aim of identifying B-CLL involved / associated genes in order to shed light on the biology of this pathological entity. Material and methods: The samples of the peripheral blood and bone marrow of 44 Ukrainian B-CLL patients with no characteristics indicative of unfavorable course of the disease such as CD38 were analyzed morphologically and immunocytochemically according to the new WHO classification. Total RNA was isolated, and gene expression levels were determined by microarray method comparing with the sample from 17 healthy donors. Results: We investigated interactions using the Ingenuity Pathway Analysis (IPA) software and found 1191 network eligible up-regulated genes and 3398 Functions/Pathways eligible up-regulated genes, 1225 network eligible down-regulated genes and 2657 Functions/Pathways eligible down-regulated genes. Conclusion: In B-CLL patients, gene networks around MYC, HNF1A and HNF4A, YWHAG, NF-κB1 and SP1 are identified as up-regulated; CEBPA, YWHAG, SATB1 and RB1 — as down-regulated. G protein coupled receptor signaling, arachidonic acid and linoleic acid metabolisms, calcium signaling, metabolism of xenobiotics by cytochrome P450 are found out as significant up-regulated pathways. EIF2 and Cdc42 signaling, regulation of eIF4 and p70S6k signaling, protein ubiquitination pathway and oxidative phosphorylation are the most significant down-regulated pathways obtained in our study. The involvement of NF-κB gene network and upregulated levels of G protein coupled receptor signaling pathway, which has an important role in transcription of NF-κB, are important and need further examination.
format Article
author Savli, H.
Sunnetci, D.
Cine, N.
Gluzman, D.F.
Zavelevich, M.P.
Sklyarenko, L.M.
Nadgornaya, V.A.
Koval, S.V.
author_facet Savli, H.
Sunnetci, D.
Cine, N.
Gluzman, D.F.
Zavelevich, M.P.
Sklyarenko, L.M.
Nadgornaya, V.A.
Koval, S.V.
author_sort Savli, H.
title Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period
title_short Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period
title_full Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period
title_fullStr Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period
title_full_unstemmed Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period
title_sort gene expression profiling of b-cll in ukrainian patients in post-chernobyl period
publisher Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України
publishDate 2012
topic_facet Original contributions
url http://dspace.nbuv.gov.ua/handle/123456789/138717
citation_txt Gene expression profiling of B-CLL in Ukrainian patients in post-Chernobyl period / H. Savli, D. Sunnetci, N. Cine, D.F. Gluzman, M.P. Zavelevich, L.M. Sklyarenko, V.A. Nadgornaya, S.V. Koval // Experimental Oncology. — 2012. — Т. 34, № 1. — С. 57-63. — Бібліогр.: 47 назв. — англ.
series Experimental Oncology
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fulltext Experimental Oncology ��� ������ ���� ��arc����� ������ ���� ��arc�� ��arc�� �� GENE EXPRESSION PROFILING OF B-CLL IN UKRAINIAN PATIENTS IN POST-CHERNOBYL PERIOD H. Savli1,*, D. Sunnetci1, N. Cine1, D.F. Gluzman2, M.P. Zavelevich2, L.M. Sklyarenko2, V.A. Nadgornaya2, S.V. Koval2 1Medical Genetics Department, Medicine Faculty of Kocaeli University, Turkey 2R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, NAS of Ukraine, Kyiv, Ukraine Background: Genetic mechanisms that result in the development and progression of B-cell chronic lymphocytic leukemia (B-CLL) are mainly unknown. We have analyzed gene expression patterns in Ukrainian B-CLL patients with the aim of identifying B-CLL involved / associated genes in order to shed light on the biology of this pathological entity. Material and methods: The samples of the peripheral blood and bone marrow of 44 Ukrainian B-CLL patients with no characteristics indicative of unfavorable course of the disease such as CD38 were analyzed morphologically and immunocytochemically according to the new WHO classification. Total RNA was isolated, and gene expression levels were determined by microarray method comparing with the sample from 17 healthy donors. Results: We investigated interactions using the Ingenuity Pathway Analysis (IPA) software and found 1191 network eligible up-regulated genes and 3398 Functions/Pathways eligible up-regulated genes, 1225 network eligible down-regulated genes and 2657 Functions/Pathways eligible down-regulated genes. Conclusion: In B-CLL patients, gene networks around MYC, HNF1A and HNF4A, YWHAG, NF-κB1 and SP1 are identified as up-regulated; CEBPA, YWHAG, SATB1 and RB1 — as down-regulated. G protein coupled receptor signaling, arachidonic acid and linoleic acid metabolisms, calcium signaling, metabolism of xenobiotics by cytochrome P450 are found out as significant up-regulated pathways. EIF2 and Cdc42 sig- naling, regulation of eIF4 and p70S6k signaling, protein ubiquitination pathway and oxidative phosphorylation are the most significant down-regulated pathways obtained in our study. The involvement of NF-κB gene network and upregulated levels of G protein coupled recep- tor signaling pathway, which has an important role in transcription of NF-κB, are important and need further examination. Key Words: B-CLL, gene expression profiling, microarray analysis, gene networks. Ionizing radiation �IR� is one of t�e most studied carcinogens in t�e development of multiple myeloma� primary myelofibrosis� polycyt�emia vera� non-Hodg- kin’s lymp�omas� myelodysplastic syndromes and some forms of acute and c�ronic leukemia� especially in acute myelogenous leukemia �A�L� [�� �]. Until re- cently� c�ronic lymp�ocytic leukemia �CLL� �as not been considered as a radiation-associated leukemia. Nev- ert�eless� current understanding of radiation-induced tumorigenesis and t�e etiology of lymp�atic neoplasia s�ow t�at IR exposure increases CLL risk [�]. After C�ernobyl nuclear accident� people living in t�e contaminated areas of Ukraine are still exposed to low doses of IR. Analysis of t�e patients wit� various forms of t�e malignancies of �ematopoietic and lym- p�oid tissues �as not revealed t�e differences in B-CLL percentage among C�ernobyl clean-up wor kers and Ukrainian population in w�ole. B-CLL was s�own to be a predominant form of �ematopoietic malignancies in clean-up workers as well as in general population [�]. Genetic mec�anisms t�at result in t�e development and progression of CLL are mainly unknown [�]. Gene expres- sion profiling by microarray is useful to understand B-CLL origin and development [�]. T�e analysis of t�e molecular genetic features s�ould be advantageous in elucidating t�e putative association of IR and B-CLL. Earlier� we �ave studied gene expressions of seve- ral apoptosis related genes in different types of tumors of �ematopoietic and lymp�oid tissues in �89 patients including t�ose wit� B-CLL living in areas of Ukraine contaminated wit� radionuclides in post-C�ernobyl period [�]. In t�e present study� we �ave analyzed gene expression patterns in samples from �� B-CLL Ukrainian patients in post-C�ernobyl period wit� t�e aim of iden- tifying t�e genes related to or involved in t�is pat�ology in order to s�ed lig�t on t�e biology of B-CLL. MATERIAL AND METHODS T�e samples of t�e perip�eral blood of B-CLL patients were obtained from R.E. Kavetsky Institute of Experimen- tal Pat�ology� Oncology and Radiobio logy of t�e National Academy of Sciences of Ukraine. All t�e patients were referred to Reference Laboratory of Immunocytoc�em- istry and Onco�ematology Department of t�e Institute for verifying t�e diagnosis. Bone marrow and perip�eral blood smears stained by �ay-Grunwald-Giemsa were studied morp�ologically. Immunocytoc�emical tec�niques �APAAP� LSAB-AP� and a broad panel of monoclonal antibodies against lineage specific� differentiation and activation antigens of leukocytes were employed for immunop�e- notyping pat�ological cells in blood and bone marrow. T�e main forms and cytological variants of �ematological malignancies were diagnosed according to new WHO clas- sification [8]. All t�e samples were immunop�enotyped� and only �� samples from CD�8-negative B-CLL patients out of ��� diagnosed patients wit� B-CLL/B-cell lymp�oma from small lymp�ocytes [�] were included in t�e study. Control group comprised perip�eral blood samples from �� �ealt�y donors. T�e et�ic committees of bot� collaborat- ing researc� institutions approved t�e design of t�e study. Total RNA isolation. Total RNA was isolated from mononuclear cells for eac� patient using QIAamp RNA Blood �ini Kit �QIAGEN� Valencia� CA� USA� and treated Received: February 2, 2012. *Correspondence: E-mail: hakansavli@yahoo.com Abbreviations used: AML — acute myelogenous leukemia; B-CLL — B-cell chronic lymphocytic leukemia; IPA — Ingenuity Pathway Analysis; IR — ionizing radiation. Exp Oncol ���� ��� �� ����� �8 Experimental Oncology ��� ������ ���� ��arc�� wit� DNase I according to t�e manufacturer’s instruc- tions. T�e quality of t�e RNA was assessed by loading ��� ng of total RNA onto an RNA Labc�ip �Agilent Tec�- nologies� Waldbronn� Germany�� followed by analysis �A���� Bioanalyzer; Agilent Tec�nologies�. An RNA integrity value �RIN� of �.� was considered acceptable. RNAs from �� B-CLL patients and �� �ealt�y donors were pooled seperately. Pooling process was performed in t�e way t�at ��� ng RNA sample was used from eac� B-CLL patient/�ealt�y donor. Eac� RNA pool was pre- pared as t�ree replicates. Microarray analysis. �icroarray analysis was performed using t�e W�ole Human Genome Oligo �i- croarray �Agilent Tec�nologies�� encompassing more t�an ������ �uman DNA probes. T�e full list of cDNAs is available online �www.agilent.com�. Protocols for sample preparation and �ybridization of t�e mononuclear cells were adaptations of t�ose in t�e Agilent Tec�nical �anual. In s�ort� first strand cDNA was trans cribed from ��� ng of total RNA using T�-Oligo�dT� Promoter Primer. Samples were transcribed in vitro and Cy-�-labelled by using a Quick-A�P labeling kit �Agilent Tec�nologies�. Following a furt�er clean-up round �Qiagen�� cRNA was fragmented into pieces ranging from �� to ��� bases in size. Fragmented cRNA samples ��.�� mg� were �ybrid- ized onto c�ips by means of �� � of incubation at ��°C wit� constant rotation� followed by a two-step microarray was� of � min in two was�ing buffers �Agilent Tec�nologies�. Hy- bridized microarrays were scanned in a Agilent Tec�nolo- gies Scanner �model G����B� and numerical results were extracted wit� Feature Extraction version 9.�.�.� using ���8��_D_F_�����8�� grid� GE�-v�_9�_Feb�� protocol and GE�_QC�_Feb�� QC metric set. T�e microarray data were analyzed using GeneSpring software version 9.� �Agilent Tec�nologies� Santa Clara� CA�. T�e fold c�anges were analyzed by filtering t�e dataset using P-value < �.�� and a signal-to-noise ratio >� for use in T-test statistical analysis. Additional filter- ing �minimum �-fold c�ange� was applied to extract t�e most t�ese genes� w�ic� were analyzed using Ingenuity Pat�way Analysis �IPA� software �Ingenuity Systems� Redwood City� CA�. T�ose genes wit� known gene sym- bols �HUGO� and t�eir corresponding expression values were uploaded into t�e software. Eac� gene symbol was mapped to its corresponding gene object in t�e Ingenu- ity Pat�ways Knowledge Base. Networks of t�ese genes were algorit�mically generated based on t�eir connec- tivity and assigned a score. T�e score is a numerical value used to rank Networks according to �ow relevant t�ey are to t�e genes in t�e input dataset but may not be an indication of t�e quality or significance of t�e net- work. T�e score takes into account t�e number of focus genes in t�e network and t�e size of t�e network to ap- proximate �ow relevant t�is network is to t�e original list of focus genes. T�e network identified is t�en presented as a grap� indicating t�e molecular relations�ips between genes/gene products. Genes are represented as nodes� and t�e biological relations�ip between two nodes is rep- resented as an edge �line�. T�e intensity of t�e node color indicated t�e degree of up- or down-regulation. T�e node s�apes are disclosed in corresponding figure legends. Canonical pat�way analysis identified t�e pat�ways from t�e IPA library of canonical pat�ways� w�ic� were most significant to t�e input data set. T�e significance of t�e association between t�e data set and t�e canonical pat�- way was determined based on two parameters: ��� A ratio of t�e number of genes from t�e data set t�at map to t�e pat�way divided by t�e total number of genes t�at map to t�e canonical pat�way and ��� a P value calculated using Fisc�er’s exact test determining t�e probability t�at t�e association between t�e genes in t�e data set and t�e canonical pat�way is due to c�ance alone. Quantitative real-time PCR (Q-RT-PCR). cDNA was synt�esized using RevertAid First Strand cDNA Synt�esis Kit �Fermentas Inc.� �aryland� USA�. Q-RT- PCR was performed as we described previously for determination of MYC� BAX� BCL-2 and FAS1 gene ex- pressions [9� ��]. Standard curves were obtained using serial dilutions of t�e beta-globulin gene �DNA Control Kit� Roc�e�. Gene-specific primers �Table �� were ob- tained from Integrated DNA Tec�nologies �Iowa� USA�. Obtained gene expression values were normalized us- ing a �ousekeeping gene of beta� microglobulin. Gene expression ratios were compared in patient and control groups using REST �Relative Expression Software Tool�. Table 1. List of the primers used for the quantitative RT-PCR Genes Primer sequences Beta2 microglobulin (F) 5’ TGA CTT TGT CAC AGC CCA AGA TA 3’ (R) 5’ AAT CCA AAT GCG GCA TCT TC 3’ BAX (F) 5’ TGC TTC AGG GTT TCA TCC AG 3’ (R) 5’ GGC GGC AAT CAT CCT CTG 3’ MYC (F) 5’ GGC AAA AGG TCA GAG TCT GG 3’ (R) 5’ GTG CAT TTT CGG TTG TTG C 3’ FAS1 (F) 5’ CAA GGG ATT GGA ATT GAG CA 3’ (R) 5’ GAC AAA GCC ACC CCA AGT TA 3’ BCL-2 (F) 5’ AGG AAG TGA ACA TTT CGG TGA C 3’ (R) 5’ GCT CAG TTC CAG GAC CAG GC 3’ RESULTS Differentially expressed genes are s�own in two separate tables. T�e ��� most up-regulated genes are s�own in Table �. T�e ��� most down-regulated genes are s�own in Table �. Bot� sets of results were obtained based on minimum �-fold c�ange using GeneSpring software version 9.� �Agilent Tec�nologies� Santa Clara� CA�. In Table � t�e gene expression results of four genes �MYC� BAX� BCL-2 and FAS1� obtained by real-time PCR and microarray met�ods are compared. Real-time PCR results of MYC� BCL-2 and BAX are in a good agreement wit� microarray expression rates. Table 4. Summarized real-time PCR confirmation results of the four genes Genes Ratios obtained by RT-PCR Ratios obtained by arrays BAX 5.0265 (Up-regulated) 2.592 (Up-regulated) BCL-2 16.696 (Up-regulated) 1.747 (Up-regulated) MYC 4.15 (Up-regulated) 2.794 (Up-regulated) FAS1 4.536 (Up-regulated) 2.460 (Down-regulated) We investigated interactions using IPA software and found ��9� network eligible up-regulated genes and ��98 Functions/Pat�ways eligible up-regulated genes. Fig. � s�ows t�e most significant four gene networks of over-expressed genes in B-CLL samples. Top func- tions of t�ese genes are related to �ematopoiesis� lipid metabolism� small molecule bioc�emistry� cancer� infec- Experimental Oncology ��� ������ ���� ��arc����� ������ ���� ��arc�� ��arc�� �9 tious diseases� cell cycle� cardiovascular system deve- lopment and function� gene expression� embryonic de- velopment� tissue morp�ology� inflammatory response. Up-regulated gene networks are identified around MYC� HNF1A and HNF4A� YWHAG� NF-κB1 and SP1. We also found ���� network eligible down-regulated genes� and ���� Functions/Pat�ways eligible down-regu- lated genes. Fig. � s�ows four gene networks of down- regulated genes in B-CLL. T�e main functions of t�e genes are related to cellular functions and maintenance� protein synt�esis� dermatological diseases and conditions� cell deat�� gene expression� inflammatory disease� cellular growt� and proliferation� post-translational modification� cancer� infectious diseases� cell morp�ology� and deve- lopment. Down-regulated gene networks are identified around CEBPA� YWHAG� SATB1 and RB1. DISCUSSION B-CLL is a �eterogeneous disease and a predominant form of �ematopoietic malignancies. Despite new molecu- lar met�ods identifying important prognostic and diagnostic genetic markers� genetic mec�anisms involved in B-CLL origin are mainly unknown. A number of novel prognostic markers suc� as Bcl-�� �AP-kinase� NF-κB� ZAP-�� were identified applying gene expression profiling before [��� ��]. We �ave analyzed gene expression patterns in sam- ples from �� B-CLL Ukrainian patients in post-C�ernobyl period to identify genes associated wit� t�is form of lym- p�oproliferative malignancy. Our study �as demon- strated new genetic networks and biological pat�ways in bot� up- and down-regulated gene expression levels. Analysis using IPA software revealed ��9� network eligible up-regulated genes and ��98 Functions/Pat�- ways eligible up-regulated genes. T�e individual genes are found in multiple categories of functions related to �ematopoiesis� lipid metabolism� small molecule bioc�emistry� cancer� infectious diseases� cell cycle� development and function of cardiovascular system� gene expression� embryonic development� tissue morp�ology� inflammatory response. One important gene network is identified around t�e up-regulated MYC and SP1 genes �Fig. �� a�. MYC� a strong proto-oncogene� plays very important roles in cell proliferation �by upregulating cyclins� downregulating p���� controlling cell growt� �by upregulating ribosomal RNA and proteins�� apoptosis �by downregulating BCL- Table 2. The 100 most up-regulated genes in B-CLL Fold Change Gene 9.971721 CB162722 9.893506 THC2579650 9.856071 IRX5 9.828577 SAPS1 9.718567 THC2671344 9.659609 LRRC2 9.598212 PIGR 9.52783 BX119852 9.385712 FMOD 9.34002 CGB1 9.180631 VPS18 9.170944 RAPH1 9.11223 RNF150 9.11183 RAP1GAP 9.109504 RPA4 9.073619 THC2672701 9.049471 CD86 9.029652 RBM22 8.81397 AA704712 8.759307 AA479896 8.743843 AKAP12 8.691222 CCDC66 8.670482 ABCA4 8.608516 CV575560 8.573189 GRAMD1C 8.567822 EFTUD1 8.518443 LOC389043 8.484631 S71486 8.467656 BTC 8.455834 SMARCA4 8.4216795 MGC39584 8.39463 BF368414 8.346779 C1orf173 8.317559 NDP 8.281372 BI826226 8.207127 RPTN 8.186712 PRRX1 8.142795 BQ286187 8.100048 L5 8.054283 ATXN3L 8.05317 AK098548 8.044337 TEF 8.034349 WDR33 8.031527 CASKIN2 8.008858 FLJ25770 7.9823356 THC2686753 7.9713397 KLHL23 7.9610386 POLR2J2 7.9588156 STARD13 7.950879 MLL Fold Change Gene 7.9061837 TTC23 7.886104 SFRP1 7.8818917 FLJ32679 7.8160353 MMP14 7.798868 MEGF10 7.7877035 WDR21C 7.775479 BU587941 7.7426653 BCR 7.7220807 THC2676656 7.706189 AI089002 7.6771984 WNT3 7.648338 UCP3 7.647829 NFE2L1 7.6217384 C1orf168 7.6014295 TMPRSS3 7.6004906 WNT2B 7.5972705 TUSC5 7.5422063 TEX12 7.522491 MGC88374 7.4850636 ST6GAL1 7.4668427 LOC645478 7.4543867 KIAA0672 7.4285965 NAV2 7.419999 THC2537502 7.419809 KIAA1946 7.3947935 BX647159 7.3545713 BG190682 7.3339643 RUNDC2B 7.3178434 GBP6 7.2903414 ZNF713 7.2862663 ASB16 7.2639813 THC2530551 7.2611523 PPM1F 7.2371364 MYOC 7.228985 LOC643401 7.2250643 KALRN 7.215619 MYCNOS 7.1989717 CRISPLD2 7.1989717 CRISPLD2 7.192935 ADIPOQ 7.192935 ADIPOQ 7.1847763 SLC44A5 7.1847763 SLC44A5 7.1711025 ZCCHC13 7.135996 SLC27A1 7.1255236 ZNF2 7.122238 MSTP9 7.0874977 PSPH 7.048849 PYY2 7.032443 AD7C-NTP Table 3. The 100 most down-regulated genes in B-CLL Fold Change Gene -9.467819 THC2588392 -8.866756 HBG1 -8.638458 SELENBP1 -8.50988 HBA2 -8.47693 HBG1 -7.8862677 SAT1 -7.8419037 FCGR3A -7.80179 RGS2 -7.7845144 SLC25A39 -7.7299724 ALAS2 -7.686287 KRT1 -7.6433597 SRGN -7.6020937 PROK2 -7.5707283 S100P -7.5505257 TNFRSF10C -7.475219 MXD1 -7.389961 HBD -7.376893 CLEC4E -7.297138 CMTM6 -7.2936077 FTL -7.292986 PAIP2 -7.2235703 ALAS2 -7.182671 HBD -7.1385164 LGALS3 -7.1038146 IFIT2 -7.0883236 ANXA1 -7.055394 AQP9 -7.054615 LOC552891 -6.935093 C6orf32 -6.9139557 PDZK1IP1 -6.892113 FBXL5 -6.8429413 CMTM2 -6.823658 HBQ1 -6.8207946 BNIP3L -6.7675858 CLC -6.7639685 AP1S2 -6.7029543 ALOX5AP -6.678584 ACTG1 -6.6524496 GIMAP7 -6.643402 GCA -6.632475 CSTA -6.6212616 PBEF1 -6.5431356 LIMK2 -6.537367 SOD2 -6.535038 TP53INP1 -6.5181375 IFIT1 -6.475131 BID -6.470724 HIST1H2AC -6.470461 DUSP1 -6.461632 MNDA Fold Change Gene -6.4505854 BCL2A1 -6.4489126 TTRAP -6.3537326 TNFAIP2 -6.341367 IL1R2 -6.3040967 FYB -6.26194 S100A12 -6.2470803 TLR2 -6.2420635 SNCA -6.2413063 PBEF1 -6.2392893 THC2586959 -6.231715 CAMP -6.2299414 S100A8 -6.2271876 KRT23 -6.193751 DYNLT1 -6.171741 SLC31A2 -6.153518 RGS18 -6.139215 SIPA1L1 -6.125804 CCR1 -6.0938168 ADD3 -6.021562 NFE2 -6.0161657 QPCT -5.994034 ITM2B -5.9857407 YPEL5 -5.9691944 IFNGR1 -5.955679 IL8RB -5.950643 C20orf24 -5.9466496 GLUL -5.9364004 NINJ1 -5.9354315 C5orf32 -5.9249115 VPS4B -5.9206657 FLJ10357 -5.9169197 HSD17B11 -5.904073 UBB -5.895618 FTL -5.894103 SAT1 -5.8842864 CKLF -5.8623157 MYL4 -5.8620443 FBXO7 -5.8529325 LCP1 -5.8372726 SNN -5.8210387 BNIP3L -5.8020077 MTPN -5.7948103 COPS5 -5.7918744 NGFRAP1 -5.782423 MFSD1 -5.7802 MPP1 -5.7671204 HIPK1 -5.7636905 PBEF1 -5.746536 PAG1 -5.7328815 APOBEC3A �� Experimental Oncology ��� ������ ���� ��arc�� 2�� differentiation and stem cell self-renewal. �utations� overexpression� rearrangement and translocation of MYC �ave been associated wit� a variety of �ematopoietic tumors� leukemias and lymp�omas� including Burkitt lymp�oma [��]. Hig� expression level of MYC �as been reported in more aggressive and apoptosis resistant forms of B-CLL and mig�t be used as molecular marker specific of resistant B-CLL subsets [��� ��]. SP�� a zinc finger transcription factor� is involved in cell differentiation� cell growt�� apoptosis� immune response� response to DNA damage� and c�romatin remodeling. SP1 and MYC are involved cooperatively in telomerase activation� w�ic� is a critical step in cellular immortalization and carcinogen- esis. Kyo et al. �ave suggested t�at t�e level of SP� ex- pression mig�t be a critical determinant of telomerase activity bot� in cancer and normal cells [��]. Anot�er network is identified around NF-κB1 gene �Fig. �� b�. NF-κB regulates several genes t�at mediate tumorigenesis and metastasis and also plays an im- portant role in pat�ogenesis of B-cell neoplasms. Car- cinogens� tumor promoters� inflammatory cytokines� and c�emot�erapeutic agents activate NF-κB and t�is activation can suppress apoptosis� t�us pro- moting c�emoresistance and tumorigenesis. B�arti et al. suggested t�at NF-κB mig�t be an ideal target for c�emoprevention and c�emosensitization [��� �8]. In addition� we �ave found NF-κB gene centered around two up- and down-regulated networks in our previous study on prostate cancer [�9]. Canonical pat�way analysis revealed t�at G-protein coupled receptor �GPCR� signaling is an important pat�way modulated by t�e up-regulated genes in B-CLL. It is known t�at GPCRs regulate proliferation� differentiation� c�emotaxis and also t�ey play an im- portant role in inflammatory diseases and cancer [��]. GPCRs are involved in control of transcription factors suc� as STAT�� NF-κB and CREB by G protein sub- families [��]. En�anced viability of CLL cells by t�e STAT� p�osp�orylation and interaction between �epa- tocyte growt� factor and its receptor �c-�ET�� w�ic� a b dc Fig. 1. Significant up-regulated gene networks identified around MYC and SP1 genes �a�� NF-κB1 gene �b�� HNF1A and HNF4A genes �c�� YWHAG gene �d� in B-CLL samples. T�e node s�apes denote enzymes � �� p�osp�atases � �� kinases � �� peptidases � �� G-protein coupled receptor � �� transmembrane receptor � �� cytokines � �� growt� factor � �� ion c�annel � �� transporter � �� translation factor � �� nuclear receptor � �� transcription factor � � and ot�er � �.T�e intensity of t�e node color-�red� indicated t�e degree of up-regulation Experimental Oncology ��� ������ ���� ��arc����� ������ ���� ��arc�� ��arc�� �� was found up-regulated in our study� was reported before [��]. CREB �cA�P response element binding protein� �ad been found overexpressed in bone mar- row samples from patients wit� acute lymp�oid and myeloid leukemia and associated wit� a poor outcome in A�L patients according to previous studies [��]. A network is also identified around HNF1A and HNF4A �Fig. �� c�. HNF�A is a transcription factor required for t�e expression of several liver-specific genes and t�e expres- sion of t�is gene is controlled by HNF�A� w�ic� may play role in development of t�e liver� kidney and intestines. Anot�er significant signaling pat�way is calcium signaling involved in many processes suc� as cell sur- vival/apoptosis� cell cycle progression� differentiation� cross-talk between intracellular compartments �ER� mitoc�ondria�� general metabolism and telomerase activ- ity. T�e calcineurin/NFAT signaling pat�way is important in lymp�oma/leukemogenesis [��]. Deregulation of t�is signaling and/or abnormal expression of its components �as been reported in solid tumors of epit�elial origin� lym- p�oma and lymp�oid leukemia. �ouse models of �uman T-ALL/lymp�oma s�owed t�e pro-oncogenic effect of ac- tive calcineurin/NFAT signaling in vivo [��]. NFAT tran- scription factors form four calcium signaling responsive members: NFATc�� NFATc�� NFATc� and NFATc�. Among t�ese members NFATc� and NFATc�� w�ic� are found up- regulated in our study� were reported to be involved in t�e development� differentiation and functioning of multiple T-and B-cell subsets in previous studies. NFATc� was found to be expressed in a majority of aggressive B-cell lymp�omas. On t�e ot�er �and� NFATc� activation was s�own to be responsible in B-CLL� in cooperation wit� STAT�� for t�e �ig� expression of CD�� [��]. �etabolism of xenobiotics by cytoc�rome P��� pat�- way �as been s�own as �ig�ly significant in our study. T�e en�anced expression of several P���s like CYP�A� CYP�C and CYP�A� t�at are up-regulated in our study� was reported in tumor cells elsew�ere [��]. Arac�idonic acid and linoleic acid metabolisms are t�e ot�er significant pat�ways modulated by t�e up- regulated genes in our study. Analysis using IPA software revealed ���� network eligible down-regulated genes� and ���� Functions/ Pat�ways eligible down-regulated genes. T�ese individual a b dc Fig.2. A significant down-regulated gene network identified around RB1 gene �a�� SATB1 gene �b� in B-CLL samples� CEBPA gene �c�� YWHAG gene �d� in B-CLL samples. T�e keys to t�e node s�apes are t�e same as in Fig. �. T�e intensity of t�e node color- �green� indicates t�e degree of down-regulation �� Experimental Oncology ��� ������ ���� ��arc�� genes are related to cell functions and maintenance� protein synt�esis� dermatological diseases and conditions� cell deat�� gene expression� inflammatory disease� cell growt� and proliferation� post-translational modification� cancer� infectious diseases� cell morp�ology� and development. One important down-regulated network is identified around RB1 gene �Fig. �� a�. T�e role of RB1 in B-CLL �as been reported based on cytogenetic data [��]. RB1 dele- tions involved in ��q�� abnormalities �ave been reported in B-CLL before [�8]. Anot�er down-regulated network is identified around SATB1 gene �Fig. �� b�. SATB1 is a new type of gene regulator expressing in various �uman cancers and t�oug�t to be re- lated to t�e malignant potential. Overexpression of t�is gene �as been reported as a predictor of poor prognosis in lung and gastric cancers [�9� ��]. An important network is identified around CEBPA gene �Fig. �� c�. CEBPA is a critical transcriptional factor and regulates t�e balance between cell proliferation and differentiation during early �ematopoietic development and myeloid differentiation [��]. CEBPA �as a tumor- suppressor function in leukemogenesis and bot� loss of function and gain of function �ave leukemogenic potential. It was reported t�at overexpression of CEBPA could contribute to B-ALL and loss of function could con- tribute to A�L [��]. On t�e ot�er �and� down-regulated CEBPA was found in acute promyelocytic leukemia stem cells in animal models [��]. Canonical pat�way analysis revealed t�at oxidative p�osp�orylation is an important pat�way modulated by t�e down-regulated genes in B-CLL. In fact� previous studies suggested t�at t�e oxidative p�osp�orylation �OXPHOS� system is severely compromised in various cancers [��]. EIF� signaling is anot�er significant pat�way. Suppres- sion of �ead and neck� colorectal carcinoma and multiple myeloma tumor growt� and/or survival by p�osp�orylation of eIF�α was reported before [��]. IPA reveals regulation of eIF� and p��s�K signa ling pat�way. eIF�E down-regulated in our study plays an im- portant role in tumor initiation and progression w�en its overexpression cooperates wit� oncogenes to acceler- ate transformation in cell lines and animal models [��]. p��s�K is a serine/t�reonine kinase and its target sub- strate is S� ribosomal protein [��]. In�ibition of p��s�K was related to cell cycle arrest at G�/G� p�ase in �uman cancer cells before [�8]. Protein ubiquitination is anot�er pat�way found signifi- cant in our study. Ubiquitination of key signaling molecules by E� ubiquitin ligases forms an important regulatory mec�anism for NF-κB signaling. Deubiquitinases �DUBs� counteract E� ligases and play a substantial role in down- regulation of NF-κB signaling and �omeostasis [�9]. Cdc�� signaling is a �ig�ly significant pat�way. Cdc�� promotes or in�ibits tumor progression depending on t�e cellular context and contributes to cancer develop- ment t�roug� its different roles in intracellular trafficking� cell cycle regulation and survival� polarity� migration and transcriptional control [��]. Cdc�� is also important in t�e development and progression of lymp�oma. Genetic knockdown or p�armacological in�ibition of Cdc�� result- ing in a cell cycle arrest and apoptosis of anaplastic large cell lymp�oma cells �as been reported [��]. An important network is identified around bot� down- regulated and up-regulated YWHAG gene in our study �Fig. � and Fig. ��. T�is gene encoding for ����-� protein gamma was found �ig�ly expressed in skeletal and �eart muscles. It �as been suggested t�at t�is protein �as an im- portant role in muscle tissue [��� ��]. ����-� proteins play critical regulatory roles in signaling pat�ways in cell division and apoptosis [��]. Furt�er investigations are required to establis� t�e function of YWHAG gene in B-CLL. Real-time PCR confirmation results of four genes �MYC� FAS1� BAX and BCL-2� s�ow t�at only MYC� BAX and BCL-2 expressions are in agreement wit� microar- ray results. Up-regulation of MYC is compatible wit� our expectations. Previous studies indicate t�at �ig� ratio of Bcl-� to Bax proteins confers a poor prognosis wit� decreased rates of complete remission and overall survival [��]. In our study� BCL-2 upregulation level is superior to t�at of BAX in real- time PCR results but not in microarrays being analyzed. FAS1 expression was found up-regulated in real-time PCR but down-regulated in microarrays in our study. It �as been reported t�at Fas expression is not very �ig� in B-CLL [��] t�at coincides wit� our fin dings of relatively small up-regulation by real-time PCR. It s�ould be noted t�at Fas was mentioned as apoptosis regulator [��] in CLL cells exposed to IR. NF-κB gene network was conspicuous in terms of being determined also in our previous studies of gene expression in prostate cancer. In addition� upregulated levels of G protein coupled receptor signaling pat�way� w�ic� �as an important role in transcription of NF-κB� need advanced examinations. In t�is sense� NF-κB gene w�ic� is important in bot� cell cycle regulation and cancer progression deserves furt�er study. Our study �as presented t�e gene expression profil- ing in B-CLL patients of Ukrainian population as w�ole. We believe t�at t�e contribution of IR as t�e putative factor in t�e origin of B-CLL s�ould be furt�er evaluated using suc� molecular genetic approac�. ACKNOWLEDGEMENTS T�e study was financed wit�in t�e framework of t�e joint researc� project �/������8 “Cytomorp�ological� immunocytoc�emical and molecular biological features of leukemias in persons exposed to ionizing radiation” ac- cording to t�e Agreement between t�e �inistry of Education and Science of Ukraine and t�e Scientific and Tec�nical Researc� Council of Turkey �TUBITAK�. REFERENCES 1. Gluzman DF, Nadgornaya VA, Machilo V, et al. Mali gnant diseases of hematopoietic and lymphoid tissues in Chernobyl clean- up workers. Hematol J 2005; 5: 565–7. 2. Boice JD, Inskip PD. Radiation-induced leukemia. In: Hen- derson ES, Lister TA, Greaves MF, (eds). Leukemia, 6th Edn. Philadelphia: WB Saunders, 1996: 195–209. 3. Richardson DB, Wing S, Schroeder J, et al. Ionizing radia- tion and chronic lymphocytic leukemia. Environ Health Perspect 2005; 113: 1–5. 4. Gluzman D, Imamura N, Sklyarenko L, et al. Patterns of hematological malignancies in Chernobyl clean-up workers (1996–2005). Exp Oncol 2006; 28: 60–3. Experimental Oncology ��� ������ ���� ��arc����� ������ ���� ��arc�� ��arc�� �� 5. Zenz T, Mertens D, Küppers R, et al. From pathogene sis to treatment of chronic lymphocytic leukaemia. Nat Rev Cancer 2010; 10: 37–50. 6. Marinello E, Carlucci F, Rosi F, et al. Purine metabolism in B-cell lymphocytic leukemia: a microarray approach. Nucleo- sides Nucleotides Nucleic Acids 2006; 25: 1277–81. 7. Savli H, Gluzman DF, Sunnetci D, et al. Quantitative real time PCR analysis of apoptosis-related gene expression in leuke- mias in Ukrainian patients. Exp Oncol 2011; 33: 104–6. 8. WHO classification of tumours of haematopoietic and lymphoid tissues. Ed. by Swerdlow SH, Campo E, Harris NL et al. Lyon, IARC 2008. 439 p. 9. Savli H, Aalto Y, Nagy B, Knuutila S, Pakkala S. Gene expression analysis of 1,25(OH)2D3-dependent differen- tiation of HL-60 cells: a cDNA array study. Br J Haematol 2002; 118: 1065–70. 10. Savli H, Karadenizli A, Kolayli F, et al. Expression stability of six housekeeping genes: A proposal for resistance gene quantifi- cation studies of Pseudomonas aeruginosa by real-time quantitative RT-PCR. J Med Microbiol 2003; 52: 403–8. 11. Gaiger A, Heintel D, Jdger U. Novel molecular diagnostic and therapeutic targets in chronic lymphocytic leukaemia. Eur J Clin Invest 2004; 34: 25–30. 12. Codony C, Crespo M, Abrisqueta P, et al. Gene expres- sion profiling in chronic lymphocytic leukaemia. Best Pract Res Clin Haematol 2009; 22: 211–22. 13. Delgado MD, Leуn J. Myc roles in hematopoiesis and leukemia. Genes Cancer 2010; 1: 605–16. 14. Halina A, Artur P, Barbara MK, et al. Alterations in TP53, cyclin D2, c-Myc, p21WAF1/CIP1 and p27KIP1 expression as- sociated with progression in B-CLL. Folia Histochem Cytochem 2010; 48: 534–41. 15. Vallat L, Magdelynat H, Merle-Byral H, et al. The resis- tance of B-CLL cells to DNA damage-induced apoptosis defined by DNA microarrays. Blood 2003; 101: 4598–606. 16. Kyo S, Takakura M, Taira T, et al. Sp1 cooperates with c-Myc to activate transcription of the human telomerase reverse transcriptase gene (hTERT). Nucleic Acids Res 2000; 28: 669–77. 17. Bharti AC, Aggarwal BB. Nuclear factor-kappa B and cancer: its role in prevention and therapy. Biochem Pharmacol 2002; 64: 883–8. 18. Liu Z, Hazan-Halevy I, Harris DM, et al. STAT-3 activates NF-kappaB in chronic lymphocytic leukemia cells. Mol Cancer Res 2011; 9: 507–15. 19. Savli H, Szendrtsi A, Romics I, Nagy B. Gene network and canonical pathway analysis in prostate cancer: a microar- ray study. Exp Mol Med 2008; 40: 176–85. 20. Fraser CC. G protein-coupled receptor connectivity to NF-kappaB in inflammation and cancer. Int Rev Immunol 2008; 27: 320–50. 21. Ho MK, Su Y, Yeung WW, Wong YH. Regulation of tran- scription factors by heterotrimeric G proteins. Curr Mol Pharmacol 2009; 2: 19–31. 22. Giannoni P, Scaglione S, Quarto R, et al. An interaction between hepatocyte growth factor and its receptor (c-MET) pro- longs the survival of chronic lymphocytic leukemic cells through STAT3 phosphorylation: a potential role of mesenchymal cells in the disease. Haematologica 2011; 96: 1015–23. 23. Cho EC, Mitton B, Sakamoto K. CREB and leukemo- genesis. Crit Rev Oncol 2011; 16: 37–46. 24. Gachet S, Ghysdael J. Calcineurin/NFAT signa- ling in lymphoid malignancies. Gen Physiol Biophys 2009; 28: F47–54. 25. Medyouf H, Ghysdael J. The calcineurin/NFAT signal- ing pathway: a novel therapeutic target in leukemia and solid tumors. Cell Cycle 2008; 7: 297–303. 26. McFadyen MC, Melvin WT, Murray GI. Cytochrome P450 enzymes: novel options for cancer therapeutics. Mol Cancer Ther 2004; 3: 363–71. 27. Antosz H, Kitlińska J, Kwiatkowska-Drabik B, et al. Rb1 gene expression in B-cell lymphocytic leukaemia cases with deletion in the 13q14 region. Cytobios 1997; 92: 111–21. 28. Crossen PE. Genes and chromosomes in chronic B-cell leukemia. Cancer Genet Cytogenet 1997; 94: 44–51. 29. Lu X, Cheng C, Zhu S, et al. SATB1 is an independent prognostic marker for gastric cancer in a Chinese population. Oncol Rep 2010; 24: 981–7. 30. Selinger CI, Cooper WA, Al-Sohaily S, et al. Loss of special AT-rich binding protein 1 expression is a marker of poor survival in lung cancer. J Thorac Oncol 2011; 6: 1179–89. 31. Chapiro E, Russell L, Radford-Weiss I, et al. Overexpres- sion of CEBPA resulting from the translocation t(14;19)(q32;q13) of human precursor B acute lymphoblastic leukemia. Blood 2006; 108: 3560–3. 32. Mercher T, Gilliland DG. CEBPA dosage in leukemogen- esis. Blood 2006; 108: 3234. 33. Santana-Lemos BA, de Lima Lange AP, de Lira Bení- cio MT, et al. The CEBPA gene is down-regulated in acute pro- myelocytic leukemia and its upstream promoter, but not the core promoter, is highly methylated. Haematologica 2011; 96: 617–20. 34. Chandra D, Singh KK. Genetic insights into OXPHOS de- fect and its role in cancer. Biochim Biophys Acta 2011; 1807: 620–5. 35. Sequeira SJ, Wen HC, Avivar-Valderas A, et al. Inhibi- tion of eIF2alpha dephosphorylation inhibits ErbB2-induced deregulation of mammary acinar morphogenesis. BMC Cell Biol 2009; 10: 64. 36. Lee T, Pelletier J. Eukaryotic initiation factor 4F: a vulner- ability of tumor cells. Future Med Chem 2012; 4: 19–31. 37. Chung J, Grammer TC, Lemon KP, et al. PDGF-and insulin-dependent pp70S6k activation mediated by phosphati- dylinositol-3-OH kinase. Nature 1994; 370: 71–5. 38. Kwon HK, Bae GU, Yoon JW, et al. Constitutive activa- tion of p70S6k in cancer cells. Arch Pharm Res 2002; 25: 685–90. 39. Harhaj EW, Dixit VM. Deubiquitinases in the regula- tion of NF-κB signaling. Cell Res 2011; 21: 22–39. 40. Vega FM, Ridley AJ. Rho GTPases in cancer cell biolo gy. FEBS Lett 2008; 582: 2093–101. 41. Ambrogio C, Voena C, Manazza AD, et al. The anaplastic lymphoma kinase controls cell shape and growth of anaplastic large cell lymphoma through Cdc42 activation. Cancer Res 2008; 68: 8899–907. 42. Horie M, Suzuki M, Takahashi E, Tanigami A. Clo ning, expression, and chromosomal mapping of the human 14–3-3gam- ma gene (YWHAG) to 7q11.23. Genomics 1999; 60: 241–3. 43. Autieri MV, Carbone CJ. 14–3-3Gamma interacts with and is phosphorylated by multiple protein kinase C isoforms in PDGF-stimulated human vascular smooth muscle cells. DNA Cell Biol 1999; 18: 555–64. 44. Chen XQ, Yu AC. The association of 14–3-3gamma and actin plays a role in cell division and apoptosis in astrocytes. Bio- chem Biophys Res Commun 2002; 296: 657–63. 45. Del Poeta G, Bruno A, Del Principe MI, et al. Deregula- tion of the mitochondrial apoptotic machinery and development of molecular targeted drugs in acute myeloid leukemia. Curr Cancer Drug Targets 2008; 8: 207–22. 46. Greaney P, Nahimana A, Lagopoulos L, et al. A Fas agonist induces high levels of apoptosis in haematological malignancies. Leuk Res 2006; 30: 415–26. 47. Jones DT, Ganeshaguru K, Virchis AE, et al. Caspase 8 ac- tivation independent of Fas (CD95/APO-1) signaling may mediate killing of B-chronic lymphocytic leukemia cells by cytotoxic drugs or gamma radiation. Blood 2001; 98: 2800–7. Copyright © Experimental Oncology, 2012