title: LRP overexpression in monocytic lineage.
abstract: The failure to chemotherapy is a multi factorial phenomenon and lung resistance protein (LRP) overexpression has already been discussed as implicated in drug resistance. But its role is still discussed. In 1996, we studied the expression of LRP and P170 (MDR) in a series of leukemias, at the time of diagnosis, by immunocytochemical (ICC) method. The observation of a strong and unusual expression of LRP in acute myeloid leukemia (AML) with monocytic component led us to test (for P170 and LRP) a new series of 47 AML with different FAB subtypes. The expression of LRP was scored from 1 to 5 in blast cells and monocytes separately. We demonstrate that LRP is not correlated with clinical outcome but is statistically related to monoblastic leukemias. Code 5 reaction was found in 10/13 M5 versus the other FAB subtypes (P<10(-3)). The strongest LRP overexpression was also found in chronic myelomonocytic leukemia (four cases), reactive monocytosis (three cases) and in a dendritic cell line. In conclusion, we report that LRP is rather a marker of monocytic lineage than a prognostic index for MDR and we suggest that detection of LRP by ICC could be an argument for the diagnosis of monoblastic and monocytic leukemias.
authors.affiliation: Laboratoire d'Hématologie, Hôpital Sud, Université de Rennes, 16 Boulevard de Bulgarie, Rennes 35203, France.
authors.forename: Béatrice Ly
authors.initials: BL
authors.lastname: Sunnaram
authors.forename: Virginie
authors.initials: V
authors.lastname: Gandemer
authors.forename: Martine
authors.initials: M
authors.lastname: Sebillot
authors.forename: Nathalie
authors.initials: N
authors.lastname: Grandgirard
authors.forename: Laurence
authors.initials: L
authors.lastname: Amiot
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Leray
authors.forename: Jean E
authors.initials: JE
authors.lastname: Goasguen
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D019070:Cell Lineage; D002648:Child; D002675:Child, Preschool; D005260:Female; D006023:Glycoproteins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D007951:Leukemia, Myeloid / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000737:chemistry* / Q000473:pathology; D009363:Neoplasm Proteins / Q000032:analysis*; D015996:Survival Rate; D020394:Vault Ribonucleoprotein Particles; D000099187:Major Vault Protein
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000911:Antibodies, Monoclonal; D006023:Glycoproteins; D009363:Neoplasm Proteins; D020394:Vault Ribonucleoprotein Particles; D000099187:Major Vault Protein; C513055:ABCB1 protein, human