Search tips
Search criteria

Results 1-4 (4)

Clipboard (0)

Select a Filter Below

Year of Publication
Document Types
1.  Abiraterone and Increased Survival in Metastatic Prostate Cancer 
The New England journal of medicine  2011;364(21):1995-2005.
Biosynthesis of extragonadal androgen may contribute to the progression of castration-resistant prostate cancer. We evaluated whether abiraterone acetate, an inhibitor of androgen biosynthesis, prolongs overall survival among patients with metastatic castration-resistant prostate cancer who have received chemotherapy.
We randomly assigned, in a 2:1 ratio, 1195 patients who had previously received docetaxel to receive 5 mg of prednisone twice daily with either 1000 mg of abiraterone acetate (797 patients) or placebo (398 patients). The primary end point was overall survival. The secondary end points included time to prostate-specific antigen (PSA) progression (elevation in the PSA level according to prespecified criteria), progression-free survival according to radiologic findings based on prespecified criteria, and the PSA response rate.
After a median follow-up of 12.8 months, overall survival was longer in the abiraterone acetate–prednisone group than in the placebo–prednisone group (14.8 months vs. 10.9 months; hazard ratio, 0.65; 95% confidence interval, 0.54 to 0.77; P<0.001). Data were unblinded at the interim analysis, since these results exceeded the preplanned criteria for study termination. All secondary end points, including time to PSA progression (10.2 vs. 6.6 months; P<0.001), progression-free survival (5.6 months vs. 3.6 months; P<0.001), and PSA response rate (29% vs. 6%, P<0.001), favored the treatment group. Mineralocorticoid-related adverse events, including fluid retention, hypertension, and hypokalemia, were more frequently reported in the abiraterone acetate–prednisone group than in the placebo–prednisone group.
The inhibition of androgen biosynthesis by abiraterone acetate prolonged overall survival among patients with metastatic castration-resistant prostate cancer who previously received chemotherapy. (Funded by Cougar Biotechnology; COU-AA-301 number, NCT00638690.)
PMCID: PMC3471149  PMID: 21612468
2.  Metabolic, pathologic, and genetic analysis of prostate tissues: quantitative evaluation of histopathologic and mRNA integrity after HR-MAS spectroscopy 
NMR in biomedicine  2009;23(4):391-398.
The impact of high-resolution magic angle spinning (HR-MAS) spectroscopy on the histopathologic and mRNA integrity of human prostate tissues was evaluated. Forty prostate tissues were harvested at transrectal ultrasound (TRUS) guided biopsy (n =20) or radical prostatectomy surgery (n =20), snap-frozen on dry ice, and stored at −80°C until use. Twenty-one samples (n =11 biopsy, n =10 surgical) underwent HR-MAS spectroscopy prior to histopathologic and cDNA microarray analysis, while 19 control samples (n =9 biopsy, n =10 surgical) underwent only histopathologic and microarray analysis. Frozen tissues were sectioned at 14-μm intervals and placed on individual histopathology slides. Every 8th slide was stained with hematoxylin and eosin (H&E) and used to target areas of predominantly epithelial tissue on the remaining slides for mRNA integrity and cDNA microarray analysis. Histopathologic integrity was graded from 1 (best) to 5 (worst) by two ‘blinded’ pathologists. Histopathologic integrity scores were not significantly different for post-surgical tissues (HR-MAS vs controls); however, one pathologist’s scores were significantly lower for biopsy tissues following HR-MAS while the other pathologist’s scores were not. mRNA integrity assays were performed using an Agilent 2100 Bioanalyzer and the electrophoretic traces were scored with an RNA integrity number (RIN) from 1 (degraded) to 10 (intact). RIN scores were not significantly different for surgical tissues, but were significantly lower for biopsy tissues following HR-MAS spectroscopy. The isolated mRNA then underwent two rounds of amplification, conversion to cDNA, coupling to Cy3 and Cy5 dyes, microarray hybridization, imaging, and analysis. Significance analysis of microarrays (SAM) identified no significantly over- or under-expressed genes, including 14 housekeeping genes, between HR-MAS and control samples of surgical and biopsy tissues (5% false discovery rate). This study demonstrates that histopathologic and genetic microarray analysis can be successfully performed on prostate surgical and biopsy tissues following HR-MAS analysis; however, biopsy tissues are more fragile than surgical tissues.
PMCID: PMC2891902  PMID: 20033906
cDNA microarray; gene expression; high resolution magic angle spinning (HR-MAS) spectroscopy; prostate cancer; radical prostatectomy; RNA integrity number (RIN); significance analysis of microarrays (SAM); transrectal ultrasound (TRUS) guided biopsy
3.  Gene Expression and Biological Pathways in Tissue of Men with Prostate Cancer in a Randomized Clinical Trial of Lycopene and Fish Oil Supplementation 
PLoS ONE  2011;6(9):e24004.
Studies suggest that micronutrients may modify the risk or delay progression of prostate cancer; however, the molecular mechanisms involved are poorly understood. We examined the effects of lycopene and fish oil on prostate gene expression in a double-blind placebo-controlled randomized clinical trial.
Eighty-four men with low risk prostate cancer were stratified based on self-reported dietary consumption of fish and tomatoes and then randomly assigned to a 3-month intervention of lycopene (n = 29) or fish oil (n = 27) supplementation or placebo (n = 28). Gene expression in morphologically normal prostate tissue was studied at baseline and at 3 months via cDNA microarray analysis. Differential gene expression and pathway analyses were performed to identify genes and pathways modulated by these micronutrients.
Global gene expression analysis revealed no significant individual genes that were associated with high intake of fish or tomato at baseline or after 3 months of supplementation with lycopene or fish oil. However, exploratory pathway analyses of rank-ordered genes (based on p-values not corrected for multiple comparisons) revealed the modulation of androgen and estrogen metabolism in men who routinely consumed more fish (p = 0.029) and tomato (p = 0.008) compared to men who ate less. In addition, modulation of arachidonic acid metabolism (p = 0.01) was observed after 3 months of fish oil supplementation compared with the placebo group; and modulation of nuclear factor (erythroid derived-2) factor 2 or Nrf2-mediated oxidative stress response for either supplement versus placebo (fish oil: p = 0.01, lycopene: p = 0.001).
We did not detect significant individual genes associated with dietary intake and supplementation of lycopene and fish oil. However, exploratory analyses revealed candidate in vivo pathways that may be modulated by these micronutrients.
Trial Registration NCT00402285
PMCID: PMC3164676  PMID: 21912659
4.  A comparison of RNA amplification techniques at sub-nanogram input concentration 
BMC Genomics  2009;10:326.
Gene expression profiling of small numbers of cells requires high-fidelity amplification of sub-nanogram amounts of RNA. Several methods for RNA amplification are available; however, there has been little consideration of the accuracy of these methods when working with very low-input quantities of RNA as is often required with rare clinical samples. Starting with 250 picograms-3.3 nanograms of total RNA, we compared two linear amplification methods 1) modified T7 and 2) Arcturus RiboAmp HS and a logarithmic amplification, 3) Balanced PCR. Microarray data from each amplification method were validated against quantitative real-time PCR (QPCR) for 37 genes.
For high intensity spots, mean Pearson correlations were quite acceptable for both total RNA and low-input quantities amplified with each of the 3 methods. Microarray filtering and data processing has an important effect on the correlation coefficient results generated by each method. Arrays derived from total RNA had higher Pearson's correlations than did arrays derived from amplified RNA when considering the entire unprocessed dataset, however, when considering a gene set of high signal intensity, the amplified arrays had superior correlation coefficients than did the total RNA arrays.
Gene expression arrays can be obtained with sub-nanogram input of total RNA. High intensity spots showed better correlation on array-array analysis than did unfiltered data, however, QPCR validated the accuracy of gene expression array profiling from low-input quantities of RNA with all 3 amplification techniques. RNA amplification and expression analysis at the sub-nanogram input level is both feasible and accurate if data processing is used to focus attention to high intensity genes for microarrays or if QPCR is used as a gold standard for validation.
PMCID: PMC2724417  PMID: 19619282

Results 1-4 (4)