The fibroblast growth factors (FGFs) are involved in hematopoiesis and tumorigenesis. However, little is known about the contribution of the FGFs identified within the past 10 years to leukemogenesis. To elucidate whether these FGFs (FGF-8, -9, -10, -11, -12, -13, -14, -16, -17, -18, -19, -20, and -21) are expressed in leukemic cells, we performed RT-PCR analyses using 28 cell lines. The members of a fetal-oncogenic subfamily, FGF-8/-17/-18, were often expressed (53.5%, 25.0%, and 32.1%) with the co-expression of their receptors. Realtime quantitative-PCR analysis showed that FGF-8/-17 were aberrantly expressed in patients with acute leukemia. Moreover, cell proliferation assays revealed the proliferation activity of FGF-17 on leukemic cells expressing its receptors. These results demonstrated that certain recently identified FGFs play an important role in the growth of leukemic cells, possibly with an autocrine mode of action, and that these FGFs will become novel biomarkers for hematopoietic tumors. (C) 2005 Elsevier Inc. All rights reserved.