Galoin S, al Saati T, Schlaifer D, Huynh A, Attal M, Delsol G
Department of Pathology, CHU-Purpan, Toulouse, France.
Br J Haematol. 1996 Sep;94(4):676-84. doi: 10.1046/j.1365-2141.1996.7062323.x.
Follicular lymphomas are often associated with t(14;18) chromosomal translocation. The rearrangement site (bcl-2/JH junctional region) between the two chromosomes is hypervariable regarding its size and DNA sequence, and is a potential specific marker for the neoplastic clone of each patient. We report the use of the polymerase chain reaction (PCR) technique for detecting and sequencing clonal bcl-2/JH rearrangements in lymph nodes and/or bone marrow specimens from patients with follicular lymphoma. 53 patients at diagnosis (n = 40) or at relapse (n = 13) were studied. 25 of these 53 cases were found to have the t(14;18) translocation involving either the major breakpoint region (MBR) (n = 21) or the minor cluster region (mcr) (n = 4). Since our PCR technique could detect the translocation in 1/10(6) cells we had to distinguish malignant cells from possible t(14;18)-bearing non-malignant cells which could be present during and after treatment. The bcl-2/JH junctional regions were therefore sequenced in order to synthesize an anti-junction oligonucleotide probe specific for each patient's malignant clone (clonospecific probe). Using these clonospecific probes for hybridization it was possible to detect one malignant cell mixed with 10(6) normal cells. 28 patients with advanced stage (stage III and IV), had been enrolled for treatment with myeloablative chemoradiotherapy and autologous bone marrow transplantation (ABMT). In 12 of these patients bcl-2/MBR translocation was found at diagnosis and used as a marker to detect the presence of residual lymphoma cells in serial bone marrow (BM) and peripheral blood (PB) samples. In three relapsed patients (with available tissue samples at diagnosis and relapse), clonospecific probes clearly demonstrated the same bcl-2/JH junction, thus confirming that the relapse occurred from the same malignant clone, and which remained stable without any clonal evolution of its junctional region throughout the course of the disease. These results demonstrate the value of the t(14;18) clonospecific probes as a diagnostic tool in the detection of minimal residual disease and relapses in patients with follicular lymphoma.
滤泡性淋巴瘤常与t(14;18)染色体易位相关。两条染色体之间的重排位点（bcl-2/JH连接区）在大小和DNA序列方面高度可变，是每个患者肿瘤克隆的潜在特异性标志物。我们报告了使用聚合酶链反应（PCR）技术检测和测序滤泡性淋巴瘤患者淋巴结和/或骨髓标本中的克隆性bcl-2/JH重排。研究了53例诊断时（n = 40）或复发时（n = 13）的患者。在这53例病例中，发现25例存在t(14;18)易位，涉及主要断裂点区域（MBR）（n = 21）或次要簇区域（mcr）（n = 4）。由于我们的PCR技术能够在1/10(6)个细胞中检测到易位，因此我们必须将恶性细胞与治疗期间及治疗后可能存在的携带t(14;18)的非恶性细胞区分开来。因此，对bcl-2/JH连接区进行测序，以合成针对每个患者恶性克隆的抗连接寡核苷酸探针（克隆特异性探针）。使用这些克隆特异性探针进行杂交，可以检测出与10(6)个正常细胞混合的一个恶性细胞。28例晚期（III期和IV期）患者参加了清髓性放化疗和自体骨髓移植（ABMT）治疗。在这些患者中，12例在诊断时发现bcl-2/MBR易位，并将其用作标志物来检测系列骨髓（BM）和外周血（PB）样本中残留淋巴瘤细胞的存在。在3例复发患者（诊断和复发时均有可用组织样本）中，克隆特异性探针清楚地显示了相同的bcl-2/JH连接，从而证实复发源于同一个恶性克隆，并且在疾病过程中其连接区没有任何克隆进化，保持稳定。这些结果证明了t(14;18)克隆特异性探针作为检测滤泡性淋巴瘤患者微小残留病和复发的诊断工具的价值。
