Expression of Y box-binding protein-1 correlates with DNA topoisomerase IIalpha and proliferating cell nuclear antigen expression in lung cancer.
Y box-binding protein-1 (YB-1), a member of the DNA binding protein family, interacts with inverted CCAAT boxes (Y-boxes). Y-boxes are located on the promoter of numerous genes, such as DNA topoisomerase IIalpha (Topo IIalpha), proliferating cell nuclear antigen (PCNA) and multidrug resistance 1 (MDR1). In this study, we used immunohistochemical (IHC) staining to detect YB-1 expression in 59 lung cancer tissues and to evaluate whether YB-1 expression was associated with the expression of YB-1 target genes such as Topo IIalpha, PCNA and MDR1 in human lung carcinoma. Twenty-eight out of 59 cases (47.5%) were stained positive for YB-1 in the cytoplasm, while 30 out of 59 cases (50.8%) were positive for PCNA in the nuclei. Topo IIalpha-positive cells were detected in 16 out of 59 cases (27.1%). Eight out of 59 cases (13.6%) had greater than 5% P-gp positive cells expression. There was a significant correlation between the YB-1 and Topo IIalpha expression in small cell lung cancer (SCLC) (p=0.0242). YB-1 expression also correlated with PCNA expression in non-small cell lung cancer (NSCLC) (p=0.0001). Higher levels of YB-1 expression were associated with T3-4 and Stage III-IV tumors in adenocarcinomas (p=0.0072; p=0.0168). In contrast, no relationship was found between YB-1 expression and P-gp expression. Our study suggests that YB-1 expression correlates with Topo IIalpha and PCNA expression in lung cancer.
Gu
C
C
Department of Surgery II, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan.
Oyama
T
T
Osaki
T
T
Kohno
K
K
Yasumoto
K
K
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis / Q000235:genetics; D000230:Adenocarcinoma / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000368:Aged; D000951:Antigens, Neoplasm; D022762:CCAAT-Enhancer-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D018288:Carcinoma, Small Cell / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000378:metabolism; D004250:DNA Topoisomerases, Type II / Q000096:biosynthesis* / Q000235:genetics; D004268:DNA-Binding Proteins; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051839:NFI Transcription Factors; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen / Q000096:biosynthesis* / Q000235:genetics; D014157:Transcription Factors; D014407:Tumor Cells, Cultured; D051840:Y-Box-Binding Protein 1
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000951:Antigens, Neoplasm; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D051839:NFI Transcription Factors; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen; D014157:Transcription Factors; D051840:Y-Box-Binding Protein 1; C070856:YBX1 protein, human; D004250:DNA Topoisomerases, Type II