title: Establishment and characterization of a novel MYC/BCL2 "double-hit" diffuse large B cell lymphoma cell line, RC.
abstract: BACKGROUND
  Diffuse large B cell lymphoma (DLBCL) is the most common type of lymphoid malignancy worldwide. Approximately 5 % of cases of DLBCL are so-called double-hit lymphomas (DHL), defined by a chromosomal translocation or rearrangement involving MYC/8q24.2 in combination with another recurrent breakpoint, usually BCL2/18q21.3. Patients with MYC/BCL2 DHL are resistant to standard front-line therapy, and currently, there is no consensus for a therapeutic strategy to treat these patients. Lack of clinically relevant or validated human experimental DHL models of any type that would improve our understanding of the biologic basis of MYC/BCL2 DHL pathophysiology continues to hamper identification of valid therapeutic targets. We describe a unique MYC/BCL2 DHL cell line with morphologic features of DLBCL that we have established, designated as RC.
  
  
  METHODS
  We used tissue culture techniques to establish the RC cell line from primary DLBCL cells. We also utilized molecular and cellular biological techniques including flow cytometry, polymerase chain reaction (PCR), DNA fingerprinting, reverse-phase protein array, conventional cytogenetics, and fluorescence in situ hybridization (FISH) analysis to characterize the RC cell line. NSG-severe combined immunodeficiency (SCID) mice were utilized as a model for xeno-transplantation of RC cells.
  
  
  RESULTS
  RC cells had the following immunophenotype: positive for CD10, CD19, CD20, CD22, CD38, CD43, CD44, and CD79b and negative for CD3, CD4, CD5, CD8, CD11c, CD14, CD30, CD56, and CD200, which was identical to the primary tumor cells. Conventional cytogenetic analysis showed a t(2;8)(p12;q24.2) and t(14;18)(q32;q21.3), corresponding to MYC and BCL2 gene rearrangements, respectively. DNA fingerprinting authenticated the RC cell line to be of the same clone as the primary tumor cells. In addition, RC cells were established in SCID mice as an in vivo model for translational therapeutics studies. Proteomic analysis showed activation of the mTOR signaling pathway in RC cells that can be targeted with an mTOR inhibitor.
  
  
  CONCLUSIONS
  The data presented confirm the validity of the RC cell line as a representative model of MYC/BCL2 DHL that will be useful for both in vitro and in vivo studies of DHL pathogenesis and therapeutics.
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA. lvpham@mdanderson.org.
authors.forename: Lan V
authors.initials: LV
authors.lastname: Pham
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA.
authors.forename: Gary
authors.initials: G
authors.lastname: Lu
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA.
authors.forename: Archito T
authors.initials: AT
authors.lastname: Tamayo
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA.
authors.forename: Juan
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA.
authors.forename: Pramoda
authors.initials: P
authors.lastname: Challagundla
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Jorgensen
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA.
authors.forename: L Jeffrey
authors.initials: LJ
authors.lastname: Medeiros
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 54, Houston, TX, 77030, USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Ford
mesh_terms: D000818:Animals; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D053631:Interleukin Receptor Common gamma Subunit / Q000172:deficiency / Q000235:genetics; D007621:Karyotyping; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016688:Mice, Inbred NOD; D018345:Mice, Knockout; D016513:Mice, SCID; D009025:Morpholines / Q000494:pharmacology; D040901:Proteomics / Q000379:methods; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics* / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics* / Q000378:metabolism; D014178:Translocation, Genetic; D014183:Transplantation, Heterologous
chemical_list: C507942:Il2rg protein, mouse; D053631:Interleukin Receptor Common gamma Subunit; C489427:MYC protein, human; D009025:Morpholines; D019253:Proto-Oncogene Proteins c-bcl-2; D016271:Proto-Oncogene Proteins c-myc; C546624:(5-(2,4-bis((3S)-3-methylmorpholin-4-yl)pyrido(2,3-d)pyrimidin-7-yl)-2-methoxyphenyl)methanol