ABSTRACT
BACKGROUND: Androgen-sensitive prostate cancer cell-line LNCaP-FGC and androgen-resistant line LNCaP-r constitute a model for development of androgen resistance in prostate cancer. METHODS: Proteins differently expressed in the two cell-lines were identified by two-dimensional (2-D) electrophoresis and mass spectrometry. HSP60, more abundant in LNCaP-r, was studied by RT-PCR and immunohistochemistry in specimens of human prostate cancer. RESULTS: HSP60 was upregulated in LNCaP-r, nm23 in LNCaP-FGC, and titin (two isoforms) in either LNCaP-r or LNCaP-FGC. In non-malignant prostate, HSP60-staining was in the glandular compartment, particularly basal epithelial cells. In prostate cancer, most epithelial cells showed moderate-strong staining without apparent correlation between staining intensity and Gleason grade. CONCLUSIONS: The LNCaP-FGC/LNCaP-r model, characterized by 2-D electrophoresis, reveals distinct proteomic alterations. With HSP60, results from cell-lines correlated with clinical results, indicating that this model can be used for dissection of mechanisms involved in transformation to androgen resistance and assignment of protein markers in prostate cancer.
Subject(s)
Biomarkers, Tumor/metabolism , Cell Transformation, Neoplastic/metabolism , Chaperonin 60/metabolism , Prostatic Neoplasms/metabolism , Proteomics , Biomarkers, Tumor/genetics , Blotting, Western , Cell Line, Tumor , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , Chaperonin 60/genetics , Electrophoresis, Gel, Two-Dimensional , Epithelial Cells/metabolism , Epithelial Cells/pathology , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Male , Mass Spectrometry , Prognosis , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
BACKGROUND: The mechanisms underlying the progression of prostate cancer to androgen-resistant cancer are still not fully understood. Here, we studied the genetic events associated with this transformation. METHODS: The androgen sensitive prostate cancer cells line LNCaP-FGC and its androgen resistant subline LNCaP-r were investigated using SKY, CGH, and cDNA microarray. RESULTS: Karyotypically, several additional chromosomal aberrations were seen in LNCaP-r as compared to the parental line. CGH also revealed unique net chromosomal alterations in LNCaP-r compared to LNCaP-FGC, including gain of 2p13-23, 2q21-32, and 13q and loss of 6p22-pter. cDNA microarray analysis identified several genes involved in DNA methylation, such as DNMT2, DNMT3a, and methyl-CpG binding domain protein 2 and 4 that were higher expressed in LNCaP-r. Interestingly, androgen responsiveness of LNCaP-r was restored after treated with DNA methyltransferase inhibitor. CONCLUSIONS: Our findings may serve as a basis for molecular dissection of the mechanisms involved in development of androgen resistant prostate cancer.
