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R C Dean

Publications and source records attributed to R C Dean.

10 recordsLinked to original sources
PubMed2003

p53 Immunostaining guided laser capture microdissection (p53-LCM) defines the presence of p53 gene mutations in focal regions of primary prostate cancer positive for p53 protein.

OBJECTIVES: A wide range of p53 mutations (5-65%), detected by various methods, has been reported in primary prostate cancers (CaP). IHC staining of radical prostatectomy specimens shows marked heterogeneity of focally distributed p53-positive cells. However, a significant relationship between the focal staining of p53 and cancer recurrence after radical prostatectomy has been noted. Increased frequency of p53 mutations has been generally observed in advanced stage CaP and metastatic prostate cancer cell lines. The significance of focal p53 immunostaining in primary CaP remains uncertain with respect to the p53 gene mutation or tumor progression. The goal of this study was to evaluate p53 gene mutations in focal regions of primary prostate cancers positive by p53 immunostaining. METHODS: Whole-mount prostates from men with clinically organ-confined prostate cancer were immunostained for p53 protein. Laser capture microdissection (LCM) was used to harvest p53 positive cells from areas of tumor and prostatic intraepithelial neoplasia and benign gland. DNA from microdissected cells were amplified for p53 exons 5-8 by polymerase chain reaction (PCR) and analyzed for mutations by single strand conformation polymorphism and DNA sequencing. Mutation analysis of the p53 gene exons 5-8 was performed in the p53 immunostaining positive focal regions (1+ to 4+) of whole-mount prostate sections from 16 patients. RESULTS: Of 16 patients with p53 IHC positive tumors, 11 (69%) had p53 gene mutations as determined by DNA sequence analysis. However, randomly microdissected tumor cells from 4 of 18 patients (22%) negative for p53 IHC also demonstrated mutations in the p53 gene. A significant fraction of prostate tumors with focally positive immunostaining for p53 have been confirmed to contain mutations in the p53 gene. CONCLUSIONS: p53 immunostaining guided LCM combined with DNA-based analyses emphasizes the presence of focal p53 mutations in primary prostate cancers and underscores the significance of previous observations showing a correlation between focal p53 immunostaining in primary CaP and cancer recurrence after radical prostatectomy.

Base Sequence↗
PubMed1999

Blinded evaluation of reverse transcriptase-polymerase chain reaction prostate-specific antigen peripheral blood assay for molecular staging of prostate cancer.

OBJECTIVES: The reverse transcriptase-polymerase chain reaction (RT-PCR)-prostate-specific antigen (PSA) assay to detect presumed occult micrometastatic prostate cancer has been controversial, and this molecular staging has been thought to be clinically useful by some groups but not others. METHODS: We used a sensitive nested RT-PCR assay with specific primers derived from the PSA sequence and a very stringent two-step PCR protocol with denaturing temperature of 94 degrees C annealing and extension temperature of 68 degrees C. This method enabled us to detect PSA-expressing LNCaP prostate cancer (PC) cells as low as one cell of 10 million lymphocytes (1/10(7)). Ninety-six patients with PC were studied, including 85 before radical prostatectomy (RP), and 22 controls, including healthy men and women and men with benign prostatic hyperplasia. RESULTS: In 85 patients undergoing RP, a minimum of two independent RT-PCR-PSA assays detected circulating prostate cells preoperatively in 27 patients (31.8%). Of 12 patients with locally advanced or advanced stage cancer, RT-PCR-PSA was positive in 5 (41.7%); of the 22 controls, no patient was RT-PCR-PSA positive. In 10 randomly selected cases, the RT-PCR product was confirmed as PSA by DNA sequencing. Of the 27 patients undergoing RP who were RT-PCR positive, 11 (40.7%) had non-organ-confined disease (pT3a or greater), and of the 58 patients who were RT-PCR negative, 32 (55.2%) had non-organ-confined disease. Patients with RT-PCR positive results also had lower margin positivity (9 of 27, 33.3%) than did patients with RT-PCR negative results (21 of 58, 36.2%). Finally, at a mean follow-up of 25.7 months, 5 (18.5%) of 27 RT-PCR positive patients had recurrence (PSA) compared with 14 (24.1%) of 58 RT-PCR negative patients. CONCLUSIONS: On the basis of this blinded study, RT-PCR for PSA-expressing cells in 85 patients before RP is not related to clinical stage, age, race, grade, Gleason sum, serum PSA or prostatic acid phosphatase, tumor volume, or tumor multifocality. RT-PCR positivity did not predict pathologic stage or early PSA recurrence. A standardized RT-PCR assay needs to be developed to account for interlaboratory discrepancies.

Aged↗
PubMed1999

Detection of circulating prostate specific antigen expressing prostatic cells in the bone marrow of radical prostatectomy patients by sensitive reverse transcriptase polymerase chain reaction.

PURPOSE: The reverse transcriptase polymerase chain reaction (RT-PCR) assay for prostate specific antigen (PSA) expressing cells in the blood circulation has been under intense investigation since 1992. Although it has been suggested that this technology could be used as molecular staging for occult prostatic hematogenous metastases, we have been unable to confirm RT-PCR PSA positivity of peripheral blood to predict stage or recurrence in radical prostatectomy cases. We performed bone marrow RT-PCR PSA assay on a large cohort of radical prostatectomy cases and evaluate the use of this assay in improving prostate cancer staging and detecting early recurrence. MATERIALS AND METHODS: Unilateral anterior iliac crest bone marrow aspirates were performed on 116 patients immediately before radical prostatectomy between February 1995 and September 1997. Radical prostatectomy specimens were processed as whole mounts. A sensitive nested RT-PCR assay with specific primers derived from the PSA sequence was used, which enabled us to detect PSA expressing LNCaP prostate cancer cells at the sensitivity of 1 cancer cell per 10 million lymphocytes (1/10(7)). A minimum of 3 RT-PCR PSA reactions were performed on all patients and at least 2 positive tests were required to define positivity. Patients were followed for PSA recurrence (mean followup 14.7 months). RESULTS: PSA expressing cells were detected in bone marrow of 51 of 116 patients (44.0%) when at least 2 of 3 RT-PCR PSA assays per patient were positive. A much higher rate of RT-PCR PSA positivity was noted (77/116 patients, 66.3%) when any RT-PCR PSA positivity was considered. In 10 randomly selected cases the RT-PCR product was confirmed as PSA by deoxyribonucleic acid sequencing. Of 51 bone marrow RT-PCR positive cases 25 (49%) had organ confined disease and 26 (51%) had nonorgan confined disease. Similarly, bone marrow RT-PCR PSA was not associated with age, race, grade, pretreatment PSA or prostatic acid phosphatase value, clinical stage or margin status. However, the 2-year disease-free survival was 96.6% in RT-PCR negative patients versus 77.5% in RT-PCR positive patients (p = 0.054), and bone marrow RT-PCR PSA was an independent prognostic factor in multivariate analysis including PSA, Gleason grade and pathological stage. CONCLUSIONS: Bone marrow RT-PCR PSA positivity in this study did not predict pathological stage, grade or margin positivity as determined from whole mount prostate cancer specimens. Furthermore, no relationship with age, grade or serum markers and bone marrow RT-PCR PSA positivity was noted. However, bone marrow RT-PCR PSA was associated with early disease recurrence. Further studies and longer followup are warranted to define the metastatic potential of the PSA expressing cells in the bone marrow of prostate cancer patients.

Aged↗
PubMed1998

New tumor markers of testis cancer.

Potential tumor markers for testis cancer have become numerous with the new molecular techniques available. New protein markers have been evaluated, and histologic factors have shown correlations with stage of disease. Cytogenetic analysis studies have also shown associations with stage progression. Chromosomal markers, oncogenes, and tumor suppressor genes are possible candidates for tumor markers. These new potential tumor markers may become as commonplace as the established markers and may enhance diagnosis, staging, and treatment of testis cancer.

Biomarkers, Tumor↗
PubMed1993

Effects of the Persian Gulf War on veterans with combat-related post-traumatic stress disorder.

The authors prospectively studied 32 male veterans with combat-related post-traumatic stress disorder (PTSD) during the Persian Gulf War. The veterans were enrolled in a Veterans Affairs mental health clinic and met the DSM-III-R criteria for PTSD. The purpose of the study was to evaluate exacerbation and reactivation of PTSD symptomatology utilizing the Mississippi Scale and the Impact of Event Scale, two widely used self-report inventories for assessment of PTSD symptoms. Results did not support an increase in the PTSD symptoms of avoidance and intrusion during the actual combat period. Possible reasons for this finding are discussed.

Adult↗
PubMed1989

Clozapine treatment of psychosis in Parkinson's disease.

Treating psychosis in patients with Parkinson's disease (PD) is one of the more difficult problems in clinical psychiatry. In this case report, a patient with PD and psychosis was treated with the novel neuroleptic clozapine and sustained improvement in both behavior and PD symptoms.

Clozapine↗
PubMed1984

DOPA decarboxylase activity in the nervous system and the ctenidium of the freshwater clam, Musculium (Sphaerium) transversum.

Dopa decarboxylase was measured in ganglia, connectives, branchial nerve and ctenidium of the clam, Musculium transversum. DOPA decarboxylase inhibitors (STH, HMD, and alpha-methyl-DOPA) reduced the enzymatic activity in all extracts. Ligation and extirpation of the visceral ganglion and branchial nerve significantly decreased the enzymatic activity in the ctenidium. Scanning electron microscopic observations showed numerous degenerative changes in nerve cells with progressive destruction of axons within the branchial nerve. In conclusion, it appears that lateral ctenidial cilia are dependent upon the decarboxylase activity of the visceral ganglion and branchial nerve.

Animals↗