Transforming activity of purinergic receptor P2Y, G protein coupled, 8 revealed by retroviral expression screening.
Biphenotypic acute leukemia (BAL) is a relatively rare subtype of acute leukemia characterized by the presence of both myeloid and lymphoid cell surface antigens. We have now screened for transforming genes in BAL blasts with the use of the focus formation assay with a retroviral cDNA expression library constructed from malignant blasts isolated from a BAL patient. Some of the retroviral inserts recovered from transformed foci were found to encode wild-type purinergic receptor P2Y, G protein coupled, 8 (P2RY8). The oncogenic potential of P2RY8 was confirmed with the in vitro focus formation assay as well as with an in vivo tumorigenicity assay in nude mice. A variety of luciferase-based reporter assays revealed that P2RY8 increased both the trans-activation activities of CREB and Elk-1 as well as the transcriptional activities of the serum response element and enhancer-promoter fragments of the c-Fos and c-Myc genes. Quantitation of P2RY8 mRNA in CD34(+) cells of bone marrow showed that P2RY8 expression is frequently increased in leukemia patients, especially in those with refractory disease. Our data thus reveal an abundant expression of P2RY8 in leukemic cells and its unexpected role in the pathogenesis of acute leukemia.
Fujiwara
Shin-Ichiro
S
Divisions of Functional Genomics, Jichi Medical University, Tochigi, Japan.
Yamashita
Yoshihiro
Y
Choi
Young Lim
YL
Watanabe
Hideki
H
Kurashina
Kentaro
K
Soda
Manabu
M
Enomoto
Munehiro
M
Hatanaka
Hisashi
H
Takada
Shuji
S
Ozawa
Keiya
K
Mano
Hiroyuki
H
D016475:3T3 Cells; D000818:Animals; D018952:Antigens, CD34 / Q000096:biosynthesis; D001854:Bone Marrow Cells / Q000378:metabolism; D045744:Cell Line, Tumor; D018076:DNA, Complementary / Q000235:genetics; D015973:Gene Expression Regulation, Leukemic; D015723:Gene Library; D006801:Humans; D007938:Leukemia / Q000235:genetics* / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D011983:Receptors, Purinergic / Q000096:biosynthesis / Q000502:physiology*; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D058470:Receptors, Purinergic P2Y / Q000096:biosynthesis / Q000378:metabolism* / Q000502:physiology*; D012190:Retroviridae / Q000378:metabolism*; D014158:Transcription, Genetic; D049368:Receptors, Lysophosphatidic Acid
D018952:Antigens, CD34; D018076:DNA, Complementary; D011983:Receptors, Purinergic; D018048:Receptors, Purinergic P2; D058470:Receptors, Purinergic P2Y; C082320:LPAR4 protein, human; D049368:Receptors, Lysophosphatidic Acid; C523574:Lpar4 protein, mouse; C578279:P2RY8 protein, human