Imaging flow cytometry-based multiplex FISH for three IGH translocations in multiple myeloma

• Published in: Journal of human genetics Vol. 68; no. 7; pp. 507 - 514
• Main Authors: Tsukamoto, Taku, Kinoshita, Masaki, Yamada, Kazuhiro, Ito, Hodaka, Yamaguchi, Toshikazu, Chinen, Yoshiaki, Mizutani, Shinsuke, Fujino, Takahiro, Kobayashi, Tsutomu, Shimura, Yuji, Inazawa, Johji, Kuroda, Junya
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 01.07.2023; Springer Nature Singapore
• Subjects: Chromosome translocations; Chromosomes, Human, Pair 14 - genetics; Decision making; Fibroblast growth factor receptors; Flow Cytometry; Fluorescence in situ hybridization; Gene Rearrangement; Heavy chains; Humans; Immunoglobulins; In Situ Hybridization, Fluorescence - methods; Interphase; Monoclonal gammopathy; Multiple myeloma; Multiple Myeloma - diagnosis; Multiple Myeloma - genetics; Multiple Myeloma - pathology; Translocation, Genetic - genetics; Tumor cells
• ISSN: 1434-5161; 1435-232X; 1435-232X
• DOI: 10.1038/s10038-023-01136-2

Three types of chromosomal translocations, t(4;14)(p16;q32), t(14;16)(q32;q23), and t(11;14)(q13;q32), are associated with prognosis and the decision making of therapeutic strategy for multiple myeloma (MM). In this study, we developed a new diagnostic modality of the multiplex FISH in immunophenotyped cells in suspension (Immunophenotyped-Suspension-Multiplex (ISM)-FISH). For the ISM-FISH, we first subject cells in suspension to the immunostaining by anti-CD138 antibody and, then, to the hybridization with four different FISH probes for genes of IGH , FGFR3 , MAF , and CCND1 tagged by different fluorescence in suspension. Then, cells are analyzed by the imaging flow cytometry MI-1000 combined with the FISH spot counting tool. By this system of the ISM-FISH, we can simultaneously examine the three chromosomal translocations, i.e, t(4;14), t(14;16), and t(11;14), in CD138-positive tumor cells in more than 2.5 × 10 4 nucleated cells with the sensitivity at least up to 1%, possibly up to 0.1%. The experiments on bone marrow nucleated cells (BMNCs) from 70 patients with MM or monoclonal gammopathy of undetermined significance demonstrated the promising qualitative diagnostic ability in detecting t(11;14), t(4;14), and t(14;16) of our ISM-FISH, which was more sensitive compared with standard double-color (DC) FISH examining 200 interphase cells with its best sensitivity up to 1.0%. Moreover, the ISM-FISH showed a positive concordance of 96.6% and negative concordance of 98.8% with standard DC-FISH examining 1000 interphase cells. In conclusion, the ISM-FISH is a rapid and reliable diagnostic tool for the simultaneous examination of three critically important IGH translocations, which may promote risk-adapted individualized therapy in MM.