Androgen receptor protein expression in prostatic tissues in black and caucasian men

Olapade-Olaopa, E.O.; C, Muronda; MacKay, E H; Danso, Alex P.; Sandhu, D. P. S.; Terry, Tim; Habib, Fouad K.

doi:10.1002/pros.20014

Cited by 22 publications

(15 citation statements)

References 34 publications

(41 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…AR expression in prostate cancer has been previously reported to be increased in black Americans in comparison with Caucasian patients, supporting the hypothesis that differential expression of AR protein may be driven at least in part by genetic events (22). Moreover, short variants of the AR gene have been shown to induce increased transcriptional activity and high AR protein levels (23).…”

Section: Discussionmentioning

confidence: 56%

Differential Expression of Genes Related to Androgen and Estrogen Metabolism in Hereditary versus Sporadic Prostate Cancer

Fromont

Yacoub

Valéri

et al. 2008

Cancer Epidemiology, Biomarkers &Amp; Prevention

View full text Add to dashboard Cite

The hereditary predisposition to prostate cancer is rare and accounts for <5% of cases. Except for younger age at diagnosis, no phenotypic features have been clearly associated with hereditary prostate cancer. The aim of the study was to analyze the expression of genes related to androgen and estrogen metabolism in both hereditary and sporadic prostate cancers in patients matched for clinicopathologic features. Tissues were obtained from patients included in a national familial prostate cancer registry. From the 120 cases of hereditary forms suggesting autosomal dominant Mendelian inheritance, 21 patients were treated by radical prostatectomy for whom formalin-fixed tissue was available. Twentyone sporadic cases were then matched according to age, Gleason score, and pathologic stage. Immunohistochemistry was done on tissue microarray using antibodies directed against androgen receptor (AR), estrogen receptor A (ERA), estrogen receptor B, 5A-reductase I and II, aromatase, and the proliferation marker Ki67. The percentage of AR-positive cancer cells was higher in hereditary cancer compared with sporadic cases (P < 0.004). In contrast, the mean number of ERA-positive stromal cells was lower in hereditary versus sporadic cancer (P < 0.03). This differential expression of AR and ERA suggests that a specific pattern of hormone receptors is associated with hereditary predisposition to prostate cancer. (Cancer Epidemiol Biomarkers Prev 2008;17(6):1505 -9)

show abstract

Section: Discussionmentioning

confidence: 56%

Differential Expression of Genes Related to Androgen and Estrogen Metabolism in Hereditary versus Sporadic Prostate Cancer

Fromont

Yacoub

Valéri

et al. 2008

Cancer Epidemiology, Biomarkers &Amp; Prevention

View full text Add to dashboard Cite

show abstract

“…Studies comparing the distribution of allele sizes for the CAG and GGN microsatellite repeat polymorphisms between different populations have noted shorter repeat lengths, on average, in men of African versus Caucasian descent (Kittles et al 2001;Esteban et al 2006). Consistent with the in vitro studies showing increased activity of the AR product with shorter AR CAG and GGN repeat alleles, studies have also found increased AR protein expression levels in prostatic tissues from men of African descent (Gaston et al 2003;Olapade-Olaopa et al 2004). Specifically, AR protein expression levels were estimated to be 22% higher in benign prostate cancer tissues and 81% higher in malignant prostate cancer tissues in African Americans versus Caucasian Americans (Gaston et al 2003).…”

Section: Introductionmentioning

confidence: 61%

The androgen receptor CAG and GGN repeat polymorphisms and prostate cancer susceptibility in African-American men: results from the Flint Men’s Health Study

et al. 2008

View full text Add to dashboard Cite

Repeat lengths of the CAG and GGN microsatellites in exon 1 of the androgen receptor (AR) gene have been hypothesized to be associated with prostate cancer risk. In vitro studies have showed an inverse association between AR CAG and GGN repeat length and activity levels of the AR product. It is known that men of African descent have a higher incidence of and greater mortality from prostate cancer than men of Caucasian or Asian descent and, on average, a smaller number of repeats at AR CAG and GGN. Consistent with these findings, studies have also found increased AR protein expression levels in benign prostatic hyperplasia and prostatic diseased tissues from men of African descent. Despite these findings, limited studies have been conducted to evaluate the association between repeat lengths at AR CAG and prostate cancer risk in African Americans. Our study is the first such study to examine whether repeat length of the AR GGN repeat is associated with prostate cancer risk in African Americans. We found no evidence for an association between AR CAG or GGN repeat lengths and prostate cancer risk in a population-based sample of African Americans.

show abstract

“…17 Moreover, recent evidence has indicated a higher androgen receptor expression in BPH epithelium of African-American compared to Caucasian men. 18 While we acknowledge the controversial reported correlation between testosterone levels and sexual health in eugonadal men, it is clear that testosterone levels and mainly the bioavailability of testosterone have a significant impact on sexual behavior and ejaculatory function in hypogonadal men. 19 In our subanalysis, total testosterone and hypogonadism did not seem to have a significant impact when sexual performance was compared in both groups after adjusting for all other risk factors mainly for comorbidities and age.…”

Section: Correlation Between Luts and Edmentioning

confidence: 79%

Correlation between LUTS (AUA-SS) and erectile dysfunction (SHIM) in an age-matched racially diverse male population: data from the Prostate Cancer Awareness Week (PCAW)

et al. 2005

View full text Add to dashboard Cite

The relationship between lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia and sexual health in men participating in a national multicenter screening program was studied. A total of 12 679 men were screened for prostate cancer in the year 2003. Of these, 6641 men had completed both the American Urological Association Symptom Score (AUA-SS) and the Sexual Health Inventory for Men (SHIM) questionnaires. We assessed the apparent effect of comorbidities (ischemic heart disease, hypertension, hypercholesteremia and diabetes), smoking habits and testosterone level on the overall sexual health. Age and race were also assessed as factors affecting the SHIM score. We used a general linear multivariable regression analysis to express the effect of these variables on the sexual health in these men adjusting for the apparent effect of LUTS. The mean and median age of the population was 58.479.8 and 58 y, respectively. The median AUA-SS was 4/25 (mean ¼ 5.775.3) and SHIM score was 19/25 (mean ¼ 16.375.9). Of the men, 4948 (75%) were Caucasian and 1154 (17%) were from African-American racial origin. A high AUA-SS appears to have a negative effect on the overall sexual health (Po0.05) after adjusting for all other confounding factors. As expected, age showed a significant inverse correlation with SHIM score (Po0.05). Caucasian men on average appear to have a significantly higher SHIM score by 6.5 points when compared to African-American men after adjusting for age, comorbidities, smoking habits, and AUA-SS (Po0.05). However, with increasing age, the difference in SHIM score diminishes between the two groups. Further, smoking and comorbidities were strong predictors of poor sexual health performance. Interestingly, hypogonadism (testosterone o300 ng/dl) was not a significant risk factor (P ¼ 0.104) when adjusting for all other variables. Nonetheless, in a univariate analysis, testosterone levels significantly correlated with reported SHIM scores (Po0.05). The overall sexual health in aging men is substantially affected not only by age, but by the severity of their urinary symptoms after adjusting for the most common known risk factors, suggesting perhaps a common underlying pathophysiology. Moreover, race appears to constitute another neglected potential risk factor, which should be investigated further in future studies.

show abstract

Androgen receptor protein expression in prostatic tissues in black and caucasian men

Abstract: Variations in AR expression between subpopulations may contribute to the phenotypic differences of prostatic diseases in Black and Caucasian men.

Cited by 22 publications

References 34 publications

Differential Expression of Genes Related to Androgen and Estrogen Metabolism in Hereditary versus Sporadic Prostate Cancer

Differential Expression of Genes Related to Androgen and Estrogen Metabolism in Hereditary versus Sporadic Prostate Cancer

The androgen receptor CAG and GGN repeat polymorphisms and prostate cancer susceptibility in African-American men: results from the Flint Men’s Health Study

Correlation between LUTS (AUA-SS) and erectile dysfunction (SHIM) in an age-matched racially diverse male population: data from the Prostate Cancer Awareness Week (PCAW)

Contact Info

Product

Resources

About