Although most patients with acute lymphoblastic leukemia (ALL) having MLL rearrangements suffer poor treatment outcome, there exists a subgroup of patients with this disease who enjoy long-term disease-free survival. In order to verify our previously reported new classification of this type of leukemia predicting treatment outcome, we analyzed gene expression profiles of MLL-rearranged leukemic cell lines and acute myeloid leukemia (AML) samples along with the previously reported ALL samples. Hierarchical clustering and the weighted vote method showed that cell line samples formed a strong association with the poorer prognosis subgroup in the classification, and that AML samples had some relationship with the better prognosis subgroup. Highly expressed genes in the poorer prognosis subgroup combined with cell line samples compared with the better prognosis subgroup include genes related to tumor aggressiveness, such as SNCG, GRM4, and EDG4. These results support the significance of the previously described classification associated with prognosis. Large-scale clinical studies, therefore, may be worth trying on the basis of this classification.
Disclosures: This study was supported by Grant-in-aid for Scientific Research for the Encouragement of Young Scientists (B) (16790586), a Grant-in-aid for Cancer Research from the Ministry of Health and Welfare of Japan, a Grant-in-aid for Scientific Research on Priority Areas, and a Grant-in-aid for Scientific Research (B) and (C) from the Ministry of Education, Culture, Sports, Science and Technology, Japan, and the Kawano Masanori Memorial Foundation for Promotion of Pediatrics. This study was carried out as a part of The Technology Development for Analysis of Protein Expression and Interaction in Bioconsortia on R&D of New Industrial Science and Technology Frontiers, which was performed by The Industrial Science, Technology, and Environmental Policy Bureau and Ministry of Economy, Trade, and Industry and entrusted by The New Energy Development Organization.