title: Increasing expression of GST-pi MIF, and ID1 genes in chemoresistant prostate cancer cells.
abstract: The differential expression of genes and related proteins of multidrug resistance in chemoresistant prostate cancer cell lines were elucidated in this study. RNA extracted from doxorubicin-resistant rat prostate cancer (PCa) cells (AT3/ADR1000) and native PCa cells was hybridized to expression arrays containing cDNAs from 588 known genes. Differential expression of selected genes was confirmed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) analysis. Protein contents were measured by fluorescent flow cytometry and immunoblotting. Localization of selected proteins in cells was observed by immunocytochemical staining. Up-regulation of eleven genes and down-regulation of one single gene were displayed in the chemoresistant prostate cancer cells. Overexpression of mRNAs in macrophage migration inhibitory factor (MIF), DNA binding protein inhibitor 1 (ID1), and glutathione S-transferase-pi (GST-pi) were confirmed by gene-specific RT-PCR. Protein over-expression of GST-pi, MIF, and ID1 in resistant cells were 3.3-, 1.5-, and 1.5-fold to native cells, respectively. Immunocytochemistry revealed that GST-pi, MIF, and ID1 were present primarily in the cytoplasm of tumor cells, but ID1 also could be found in the nucleus. AT3/ADR1000 drug-resistant PCa cells displayed significantly increased expression of GST-pi, MIF, and ID1 proteins when compared with native PCa cells. It indicates these genes may play a role in drug resistance of prostate cancer.
authors.affiliation: Uro-Oncology Laboratory, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China. yuds@ms21.hinet.net
authors.forename: D-S
authors.initials: DS
authors.lastname: Yu
authors.forename: D S
authors.initials: DS
authors.lastname: Hsieh
authors.forename: S Y
authors.initials: SY
authors.lastname: Chang
mesh_terms: D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D019008:Drug Resistance, Neoplasm; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D051549:Glutathione S-Transferase pi / Q000235:genetics*; D051798:Inhibitor of Differentiation Protein 1 / Q000235:genetics*; D008263:Macrophage Migration-Inhibitory Factors / Q000235:genetics*; D008297:Male; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000235:genetics*; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; C497453:ID1 protein, human; D051798:Inhibitor of Differentiation Protein 1; D008263:Macrophage Migration-Inhibitory Factors; D051549:Glutathione S-Transferase pi