title: Different expression profiles of Y-box-binding protein-1 and multidrug resistance-associated proteins between alveolar and embryonal rhabdomyosarcoma.
abstract: Nuclear expression of the Y-box-binding protein-1 (YB-1) has been reported to regulate the expression of both P-glycoprotein (P-gp) and major vault protein (MVP), and to regulate proliferative activities in human malignancies. Based on morphology and molecular biology, rhabdomyosarcoma (RMS) can be divided into two major types: embryonal type and the more aggressive alveolar type. Thirty-five cases of embryonal RMS (ERMS) and 28 cases of alveolar RMS (ARMS) were examined immunohistochemically for the nuclear expression of YB-1 and the intrinsic expression of P-gp, multidrug resistance (MDR)-associated protein (MRP) 1, 2, and 3, breast-cancer resistant protein (BCRP) and MVP, and the findings were compared with proliferative activities as evaluated by the MIB-1-labeling index (LI). Moreover, mRNA levels of these MDR-related molecules were assessed using a quantitative reverse transcriptase-PCR method in 18 concordant frozen materials. P-gp expression was more frequently observed ARMS, compared with ERMS (P = 0.0332), whereas immunoreactivity for BCRP was more frequently recognized in ERMS (P = 0.0184). Nuclear expression of YB-1 protein was correlated with P-gp (P = 0.0359) and MVP (P = 0.0044) expression, and a higher MIB-1-labeling index (P = 0.0244) in ERMS, however, in ARMS no such relationships were observed. These immunohistochemical results indicate that different expression profiles of MDR-related molecules and their correlation with YB-1 nuclear expression support the concept that ERMS and ARMS are molecular biologically distinct neoplasms. Apart from ERMS, frequent P-gp expression in ARMS may be independent from YB-1 regulation. However, YB-1 may be a candidate for a molecular target in rhabdomyosarcoma therapy, especially in ERMS.
authors: Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. oda@surgpath.med.kyushu-u.ac.jp
authors: Yoshinao
authors: Y
authors: Oda
authors: Kenichi
authors: K
authors: Kohashi
authors: Hidetaka
authors: H
authors: Yamamoto
authors: Sadafumi
authors: S
authors: Tamiya
authors: Kimitoshi
authors: K
authors: Kohno
authors: Michihiko
authors: M
authors: Kuwano
authors: Yukihide
authors: Y
authors: Iwamoto
authors: Tatsuro
authors: T
authors: Tajiri
authors: Tomoaki
authors: T
authors: Taguchi
authors: Masazumi
authors: M
authors: Tsuneyoshi
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D000293:Adolescent; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism; D049109:Cell Proliferation; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D018232:Rhabdomyosarcoma, Alveolar / Q000145:classification / Q000473:pathology*; D018233:Rhabdomyosarcoma, Embryonal / Q000145:classification / Q000473:pathology*; D020394:Vault Ribonucleoprotein Particles / Q000235:genetics / Q000378:metabolism*; D051840:Y-Box-Binding Protein 1 / Q000032:analysis / Q000378:metabolism*; D000099187:Major Vault Protein
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D012333:RNA, Messenger; D020394:Vault Ribonucleoprotein Particles; D051840:Y-Box-Binding Protein 1; D000099187:Major Vault Protein