title: Detection of circulating lymphoma cells in patients with non-Hodgkin lymphoma using MAGE-A3 gene expression in peripheral blood.
abstract: OBJECTIVE
  Lymphoma-specific gene expression in peripheral blood reflects the presence of circulating lymphoma cells (CLCs). MAGE-A3 is widely expressed in solid tumors and is a potent candidate for immunotherapy. To determine whether MAGE-A3 expression would be a useful marker for CLCs in non-Hodgkin lymphoma (NHL), we assessed MAGE-A3 mRNA expression in the peripheral blood of NHL patients and controls.
  
  
  METHODS
  We measured MAGE-A3 gene expression in ten lymphoma cell lines (Farage, RL, SU-DHL, Toledo, WSU-NHL, BJA-B, Daudi, Raji, Granta-519 and Jurkat) using nested RT-PCR, and determined detection sensitivity using mixtures of MAGE-A3-positive and -negative cells over a range of 1/10(6) to 10(6)/10(6) cells. MAGE-A3 expression was determined in buffy coat samples of 40 controls and 95 NHL patients prior to treatment. Clinical characteristics (e.g., cell lineage) and international prognostic indices, including age, performance, LDH, stage and extra-nodal involvement, were evaluated and related to MAGE-A3 expression. Hazard ratios, reflecting risk for overall survival and progression-free survival, were also evaluated. Follow-up MAGE-A3 expression was evaluated at two time points: after 3-4 cycles of chemotherapy (80 patients) and after 6-8 cycles of chemotherapy (74 patients).
  
  
  RESULTS
  MAGE-A3 mRNA was detected in four lymphoma cell lines - RL, Farage, Toledo and Raji - and was present in 45 of 95 (47.3%) patients with NHL, but in none of the 40 controls. The detection sensitivity was 1 in 1000 cells. MAGE-A3 expression prior to treatment was not associated with clinical features or patient survival. During follow-up, only six patients (7.5%) were positive for MAGE-A3 after 3-4 cycles of chemotherapy and three (4.1%) were positive after 6-8 cycles.
  
  
  CONCLUSIONS
  The results showed that MAGE-A3 gene expression was frequent in NHL patients and decreased after effective chemotherapy, suggesting that MAGE-A3 can be used as a tumor marker for CLCs in patients with NHL. However, MAGE-A3 expression showed no prognostic value in this group of patients.
authors.affiliation: Hematologic Malignancy Branch, Division of Translational & Clinical Research II, Research Institute and Hospital, National Cancer Center, Gyeonggi-do, Republic of Korea.
authors.forename: Mi Hwa
authors.initials: MH
authors.lastname: Han
authors.forename: Hyeon-Seok
authors.initials: HS
authors.lastname: Eom
authors.forename: Weon-Seo
authors.initials: WS
authors.lastname: Park
authors.forename: Tak
authors.initials: T
authors.lastname: Yun
authors.forename: Sohee
authors.initials: S
authors.lastname: Park
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: Kim
authors.forename: Chang-Ho
authors.initials: CH
authors.lastname: Jeon
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Kong
mesh_terms: D000951:Antigens, Neoplasm / Q000235:genetics*; D001483:Base Sequence; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D017931:DNA Primers; D005260:Female; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000097:blood* / Q000276:immunology; D008297:Male; D009363:Neoplasm Proteins / Q000235:genetics*; D009360:Neoplastic Cells, Circulating; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000951:Antigens, Neoplasm; D017931:DNA Primers; C072013:MAGEA3 protein, human; D009363:Neoplasm Proteins