Antigen Reverse Transcriptase-polymerase Chain Research Articles

The detection and isolation of viable prostate-specific antigen positive epithelial cells by enrichment: A comparison to standard prostate-specific antigen reverse transcriptase polymerase chain reaction and its clinical relevance in prostate cancer

Purpose To isolate prostate epithelial cells from the peripheral blood and bone marrow, and compare prostate-specific antigen (PSA) reverse transcriptase polymerase chain reaction (RT-PCR) performed on unenriched or epithelial enriched peripheral blood and bone marrow samples. Patients and methods Peripheral blood samples from 371 patients with prostate cancer and 141 controls, and bone marrow samples from 292 patients with prostate cancer and 43 controls were obtained. One aliquot was assessed with PSA RT-PCR. Another was enriched for epithelial cells with paramagnetic immune microbeads and assessed for: (1) PSA immunohistochemistry, (2) PSA RT-PCR, and (3) immunofluorescent detection of epithelial cells. Results In the bone marrow ( P < 0.01), but not the peripheral blood ( P = 0.62), we observed significantly higher detection rates of disseminated PSA expressing epithelial cells after enrichment. The presence of epithelial cells with or without evidence of PSA production was uncommon among controls both in peripheral blood (1% and 0%) and bone marrow (11% and 0%). In patients with active prostate cancer, 46% to 74% had epithelial cells in peripheral blood, and 20% to 64% had PSA expressing epithelial cells. In bone marrow, 55% to 92% had epithelial cells, and 43% to 83% had PSA expressing epithelial cells. Particularly in bone marrow, circulating cells were frequently detected in men without evidence of disease after prostatectomy. With limited follow-up, the detection of epithelial cells or PSA expressing epithelial cells in peripheral blood or bone marrow before radical prostatectomy does not define a population of patients that will have biochemical failure. Conclusions Immunomagnetic enrichment frequently detects epithelial, presumably malignant, cells in the peripheral blood and, especially, the bone marrow of patients with prostate cancer. Viable cells can be acquired for gene expression and phenotyping studies.

De novo expression of CD44 in prostate carcinoma is correlated with systemic dissemination of prostate cancer.

AIMS: To evaluate the role of CD44 in early steps in the development of prostate cancer, and to assess the biological significance of preneoplastic lesions in prostate cancer. METHODS: 38...

Molecular Stating of Prostate Cancer. II. A Comparison of the Application of an Enhanced Reverse Transcriptase Polymerase Chain Reaction Assay for Prostate Specific Antigen Versus Prostate Specific Membrane Antigen

Current imaging modalities used to stage prostate cancer clinically fail to detect extracapsular disease in a significant subset of patients. A molecular based peripheral blood assay using the reverse transcriptase polymerase chain reaction has recently been shown to be a highly sensitive staging modality for detecting extraprostatic disease preoperatively. The assay uses primers that are specific for prostate specific antigen (PSA). We compare the application of the reverse transcriptase polymerase chain reaction assay using primers specific for the human prostate specific membrane antigen with results obtained from the same specimens by reverse transcriptase polymerase chain reaction for PSA. Prostate specific membrane antigen, a recently cloned prostatic antigen, is a transmembrane glycoprotein that has been described as prostate specific. These assays were applied to ribonucleic acids extracted from the peripheral blood lymphocyte fraction of 80 patients with clinically localized prostate cancer. In addition, blood specimens from 20 female patients, 20 young male patients, 25 age-matched control men under treatment for benign prostatic hypertrophy and 20 men with established, untreated metastatic prostate cancer were tested. All 3 groups of noncancer patients had negative polymerase chain reactions for PSA as well as prostate specific membrane antigen. Of 20 metastatic prostate cancer patients 16 (80 percent) had positive polymerase chain reactions for PSA, while only 10 (50 percent) had positive results for prostate specific membrane antigen. Among the 80 patients with clinically localized disease (stages T1 to T2cNOMO), 27 and 19 had positive polymerase chain reaction for PSA and prostate specific membrane antigen, respectively, from blood specimens obtained preoperatively. Analyzing the final pathology in each patient with the reverse transcriptase polymerase chain reaction assay identified a significantly stronger correlation with tumor invasion using the results of the PSA test rather than the results of the prostate specific membrane antigen reverse transcriptase polymerase chain reaction test (67 percent versus 34 percent sensitivity for detecting capsular penetration, 87 percent versus 46 percent sensitivity for detecting disease to the surgical margin and 83 percent versus 16 percent sensitivity for detecting seminal vesicle invasion). In contrast to the reverse transcriptase polymerase chain reaction assay for PSA, a similar assay done for prostate specific membrane antigen did not correlate with pathological stage of prostate cancer.