Abstract 1245: Characterization of human leukemic cell lines and changes of the characteristics according to passage number

Abstract

Abstract Background: Human leukemic cell lines are valuable tools for the studies on the biology of hematologic cancers and new drug development. We investigated the baseline characteristics of human leukemic cell lines and changes of the properties according to passage number. Materials and methods: A total of 11 human leukemic cell lines were investigated in this study, including myeloid leukemia cell lines (HL60, NB4, Molm-13, MV4-11, KG-1, K562) and lymphoid leukemia cell lines (CCRFCEM, SR, U937, Molt4, Jurkat). Genetic mutations (N-Ras, K-Ras, B-Raf, FLT3-ITD, FLT3-TKD, MLL) and polymorphisms (MDR3435CT and GST genes [A, M, T]) were detected using appropriate methods such as PCR, RFLP or DNA sequencing. MDR activities were measured using Rhodamine 123 efflux assay. Establishment of xenograft model for each cell line was tried with subcutaneous injection of leukemic cells mixed with matrigel matrix into Balb/c nude mouse. Cell lines were maintained with two times of passage per week. Western blot assay was done for changes of expression of intracellular signaling pathway proteins such as ERK, p-ERK, AKT, p-AKT, and HR23B according to the passage number. Summary of results: N-Ras mutation was found in HL60 (Gln61Leu) and Molt4 (Gly13Val), K-Ras mutation in CCRFCEM (Gly12Asp) and NB4 (Ala18Asp), B-Raf mutation in none, FLT3-ITD and MLL rearrangements in Molm-13 and MV4-11, and FLT3-TKD in none. High MDR activity was noted in KG-1 (92.5%) and other cell lines showed less than 30% of MDR activities. Mouse xenograft model was established with 7 leukemic cell lines (HL60, NB4, MV4-11, Molm-13, K562, Molt4 and CCRFCEM). ERK phosphorylation was observed in most cell lines except CCRFCEM, but AKT phosphorylation was not found in any of the cell lines. As increasing the passage number, the levels of p-ERK in K562 and HL60 significantly decreased whereas those of p-AKT in Molm-13 were elevated. Conclusion: Our study results provide genetic and biologic data for human leukemic cell lines and show the importance of passage number of the leukemic cell lines in designing experiments. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1245. doi:10.1158/1538-7445.AM2011-1245