ABSTRACT
A common therapy for nonorgan-confined prostate cancer involves androgen deprivation. To develop a better understanding of the effect of androgen on prostatic cells, we have analyzed gene expression changes induced by dihydrotestosterone (DHT) in the androgen responsive prostate cancer line LNCaP, at both RNA and protein levels. Changes at the RNA level induced by DHT were determined by means of serial analysis of gene expression (SAGE), and protein profiling was done by means of quantitative two-dimensional polyacrylamide gel electrophoresis. Among 123,371 transcripts analyzed, a total of 28,844 distinct SAGE tags were identified representing 16,570 genes. Some 351 genes were significantly affected by DHT treatment at the RNA level (p < 0.05), of which 147 were induced and 204 repressed by androgen. In two independent experiments, the integrated intensity of 32 protein spots increased and 12 decreased at least two-fold in response to androgen, out of a total of 1031 protein spots analyzed. The change in intensity for most of the affected proteins identified could not be predicted based on the level of their corresponding RNA. Our study provides a global assessment of genes regulated by DHT and suggests a need for profiling at both RNA and protein levels for a comprehensive evaluation of patterns of gene expression.
Subject(s)
Androgens/pharmacology , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic/drug effects , Neoplasm Proteins/analysis , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , Proteome/analysis , Dihydrotestosterone/pharmacology , Electrophoresis, Gel, Two-Dimensional , Humans , Male , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Proteome/genetics , Proteome/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Time Factors , Tumor Cells, CulturedABSTRACT
Mixed epithelial and stromal tumor of the kidney is a recently recognized neoplasm that occurs almost exclusively in perimenopausal women. Because it frequently contains areas of smooth muscle in which epithelial structures are embedded, some have concluded that it is the adult form of congenital mesoblastic nephroma. Others have concluded that the morphology and epidemiology of mixed epithelial and stromal tumor indicate that it is unrelated to congenital mesoblastic nephroma. Although the genetic alterations of mixed epithelial and stromal tumor have not been previously elucidated, much is known about the genetic alterations of cellular congenital mesoblastic nephroma. The present study was undertaken to determine if mixed epithelial and stromal tumors have any of the genetic alterations recognized as typical of cellular congenital mesoblastic nephroma. RNA extraction was performed on formalin-fixed, paraffin-embedded tissue from 7 mixed epithelial and stromal tumors followed by reverse-transcription polymerase chain reaction to detect the ETV6-NTRK3 gene fusion. Fluorescent in situ hybridization with centromere-specific probes for chromosomes 8, 11, and 17 was performed to evaluate polyploidy of these chromosomes in 11 cases of mixed epithelial and stromal tumor. None of the mixed epithelial and stromal tumors showed any of these genetic alterations. We conclude that mixed epithelial and stromal tumor of the kidney lacks the genetic alterations typical of cellular congenital mesoblastic nephroma, is unrelated to it, and the appellation "adult mesoblastic nephroma" should not be used for these tumors.
Subject(s)
Epithelial Cells/pathology , Kidney Neoplasms/genetics , Nephroma, Mesoblastic/congenital , Nephroma, Mesoblastic/genetics , Repressor Proteins , Stromal Cells/pathology , Adult , Aged , Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 17 , Chromosomes, Human, Pair 8 , DNA-Binding Proteins/genetics , Female , Humans , In Situ Hybridization, Fluorescence , Kidney Neoplasms/pathology , Menopause , Middle Aged , Oncogene Proteins, Fusion , Ploidies , Proto-Oncogene Proteins c-ets , Receptor, trkC/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/genetics , Translocation, Genetic , ETS Translocation Variant 6 ProteinABSTRACT
Prostate cancer is the most diagnosed cancer and the second leading cause of cancer death among men in the United States. Ability to detect this cancer early and availability of better prognostic markers are critical in order to decrease morbidity and mortality of prostate cancer. With the recent development in gene expression analysis methodology, expression profiles of thousands of genes can be generated in tissue samples and cell lines. Comparison of the global gene expression patterns between normal prostate and tumors at different stages may allow us to understand better the molecular mechanism of prostate tumorigenesis and progression. Different cancer cell lines and tissues appear to have different gene expression patterns that provide a new tool to classify tumors. Molecular classification of prostate cancer holds great promise for early detection and prognosis of this disease in the future. In this review, we summarize some of the recent mRNA and protein expression profiling studies performed in prostate cancer. Further, we discuss the potential benefits and limitations of current profiling technology.
