6275

S100A4

18A2|42A|CAPL|FSP1|MTS1|P9KA|PEL98;S100 calcium binding protein A4;S100A4;S100 calcium binding protein A4

S100 calcium-binding protein A4 (calcium protein, calvasculin, metastasin, murine placental homolog)|fibroblast-specific protein-1|leukemia multidrug resistance associated protein|malignant transformation suppression 1|placental calcium-binding protein|pr

1q21

protein-coding

Preferentially expressed antigen of melanoma (PRAME) is expressed in a wide variety of tumors, but in contrast with most other tumor associated antigens, itis also expressed in leukemias. In a previous study, we showed that overexpression of PRAME induced apoptosis, inhibited cell proliferation and reduced tumorigenicity of leukemic cells in vivo. We also demonstrated that PRAME overexpression induced the repression of three genes (Hsp27, S100A4 and p21) associated with an unfavorable prognosis in leukemia. Here, we further investigated the mechanisms of PRAME-induced tumor suppression in vitro and in vivo. We performed a gene profiling study by analysing PRAME shRNA-silenced leukemic cells on high-density micro-arrays (Affymetrix) and found that PRAME altered the expression of two additional genes potentially involved in cancerogenesis and cancer progression: IL-8 and IGFBP-2. In a series of 28 acutemyeloid leukemia pediatric patients, we observed that PRAME expression was associated with an increased leukemia-free survival. Importantly, the correlation between PRAME expression in leukemic cell lines and the decreased expression of Hsp27, S100A4, p21, IL-8 and the increased expression of IGFBP-2 was also observed in vivo, in leukemic patients. Our results suggest that the favorable prognosis of PRAME could be mediated, at least in part, by the modified expression of those genes.