Promoter polymorphisms of the PCA3 gene are not associated with its overexpression in prostate cancer patients

In male, the prostate cancer (PCa) is one of the most frequent neoplasias and the second cause of cancer deaths worldwide. In 2015, more than 6000 men died in Mexico due to this disease. In this regard, prostate cancer associated gene 3 (PCA3) has become an interesting target in PCa as is found highly overexpressed. Moreover, TAAA tandem repeats have been suggested to be associated with the regulation of PCA3 expression and, in turn, to be related with the development of the disease. The aim of the study was to understand the genetic basis of the disease in search for a better diagnosis. Expression levels of PCA3 gene were analysed in tissue of 13 patients diagnosed with PCa and six patients diagnosed with a benign prostatic disease (BPD). The absolute expression of PCA3 was quantified by real-time PCR. Genotype for TAAA tandem repeats was measured using automatic sequencing and the results were analysed to determine whether an association existed between them. We identified three alleles: 4, 5, 6 and four genotypes: 4/5, 5/5, 5/6, 6/6. Our analysis identified a mutation in the nucleotide 76764237 of the PCA3 gene that generates an extra TAAA tandem repeat. The nucleotide mutation is present in 61.53% of PCa and 66.66% of BPD patients. Our study revealed the presence of a mutation in the PCA3 gene that generates an extra TAAA tandem. We observed no association between the absolute expression of PCA3 messenger and the number of TAAA repetitions.

Diagnostic value of urine-based PCA3 score in prostate cancer patients undergoing initial prostatic biopsy / 军事医学

Objective To evaluate the diagnostic value of urine-based prostate cancer antigen 3 ( PCA3 ) score in detecting prostate cancer during initial prostatic biopsy .Methods Urine was collected after digital rectal examination ( DRE) ( three strokes per lobe ) from 248 men before prostate biopsy .The specimens were collected between January 2010 and December 2012.The expression of PCA3 mRNA and prostate specifc antigen (PSA) mRNA was determined by quanti-tative real time polymerase chain reaction ( qRT-PCR ) .PCA3 scores were calculated by PCA 3 mRNA/PSA mRNA × 1000 .The ability of the PCA3 score to predict the biopsy outcome was assessed with AUC-ROC analysis and compared with the serum PSA levels.Results The rate of positive prostate biopsy was 32.3%(80 patients with positive prostatic biopsy versus 168 patients with negative prostate biopsy ) .PCA3 scores were significantly higher in patients with positive biopsy than in those with negative biopsy results (P<0.001).The ROC curve analysis demonstrated that the area under the ROC curve (AUC) of serum total PSA (tPSA), PCA3 score and the duplex model combining tPSA and PCA 3 score was 0.620, 0.693 and 0.724, respectively.Further analysis of the diagnostic performance of PCA3 score revealed that at a cut-off of 90.2456, the sensitivity was 67.5%and the specificity was 61.9%for discriminating positive biopsy from negative biopsy. The duplex model combining tPSA and PCA 3 score represented a better approach than tPSA alone in PCa diagnosis by pros-tatic biopsy (P=0.011), but there was no statistically significant difference between tPSA and PCA 3 score (P=0.160). In addition , a comprehensive diagnostic model based on multiple risk factors of prostate cancer combined with PCA 3 score could further improve the predictive accuracy of prostate cancer .Conclusion PCA3 could be a good predictor of prostate cancer in initial prostate biopsy in Chinese population .The comprehensive diagnostic model can improve the diagnostic potency .Further large-scale multicenter studies in China are needed to confirm our findings .

PCA3 score and prostate cancer diagnosis at repeated saturation biopsy. Which cut-off: 20 or 35?

PURPOSE: To compare PCA3 score cut-off of 35 vs 20 in PCa diagnosis in patients undergoing repeated saturation prostate biopsy (SPBx). MATERIALS AND METHODS: From January 2010 to May 2011, 118 patients (median 62.5 years) with primary negative extended biopsy underwent a transperineal SPBx (median 30 cores) for persistent suspicion of PCa. The indications for repeated biopsy were: persistently high or increasing PSA values; PSA > 10 ng/mL, PSA values between 4.1-10 or 2.6-4 ng/mL with free/total PSA ≤ 25% and ≤ 20%, respectively; moreover, before performing SPBx urinary PCA3 score was evaluated. RESULTS: All patients had negative DRE and median PSA was 8.5 ng/mL (range: 3.7-24 ng/mL). A T1c PCa was found in 32 patients (27.1%): PCA3 score was 59 (median; range: 7-201) in the presence of PCa and 35 (median; range: 3-253) in the absence of cancer (p < 0.05). In the presence of ASAP and HGPIN median PCA3 score was 109 (range: 42-253) and 40 (range: 30-140), respectively. Diagnostic accuracy, sensitivity, specificity, PPV and NPV of PCA3 score cut-off of 20 vs 35 in PCa diagnosis were 44.9 vs 50%, 90.6 vs 71.9%, 27.9 vs 41.8%, 31.9 vs 31.5% and 88.9 vs 80%, respectively. ROC analysis demonstrated an AUC for PCA3 ≥ 20 vs ≥ 35 of 0.678 and 0.634, respectively. CONCLUSIONS: Our data suggest that PCA3 is more useful as an exclusion tool; moreover, setting a PCA3 cut-off at 20 vs 35, would have avoided 22.9 vs 38.1% of biopsies while missing 9.4% and 28% diagnosis of PCa.

Gene expression of PCA3 in peripheral blood and urine and the significance of urine PCA3 score indiagnosis of prostate cancer / 中华泌尿外科杂志

Objective To detect the gene expression of PCA3 and PSA in peripheral blood and urine simultaneously to investigate whether PCA3 combining PSA gene could become new markers for diagnosis of Pca. Methods From June 2009 to December 2009,the initial urine after prostatic massage and the peripheral blood specimens were collected from 37 patients with PCa and 68 patients with BPH that were pathologically confirmed,g patients with urinary stone were used as normal control,the expression of PCA3 and PSA mRNA of mononuclear cells in urine sediments and peripheral blood were detected by fluorescence real-time quantitative PCR,with β-actin mRNA as internal control. Results The sensitivity and specificity of the expression of PCA3 mRNA in peripheral blood for diagnosis of prostate cancer were 48.6％ and 100％ respectively.ROC curve analysis was performed for the PCA3 score and the area under the ROC curve was 0.908.Using 64.6 as the cutoff,the sensitivity was 81.1％ and the specificity was 86.8％.In group with serum tPSA value ＜4 pg/L,the positive rate and negative rate of urinary PCA3 score for diagnosing prostate cancer were 80％ (4/5) and 89.4％ (20/22) respectively.In group with serum tPSA value 4 - 10 μg/L,the positive rate and negative rate of urinary PCA3 score were 66.7％ ( 2/3 ) and 84.2％(16/19) respectively.In group with serum tPSA value ＞ 10 μg/L,the positive rate and negative rate of urinary PCA3 score were 82.8％ (24/27) and 81.5％ (22/27) respectively.The sensitivity of simultaneous detection of PCA3 mRNA in peripheral blood and urinary PCA3 score was 86.5％. Conclusions The expression of PCA3 mRNA in peripheral blood was a specific marker for the diagnosis of PCa.The simultaneous detection of PCA3 mRNA in peripheral blood and urinary PCA3 score could increase the sensitivity for the diagnosis of PCa.

Estudo funcional do DD3 no câncer de próstata e sua interação com a via do receptor de androgênio

O gene DD3 corresponde a um RNA não codificante (ncRNA) específico da próstata. O seu papel como marcador diagnóstico no câncer de próstata (CaP) apresenta-se bem estabelecido, porém muito pouco se sabe até o presente momento sobre sua função na biologia deste tumor, bem como sobre seu envolvimento com a via do receptor de androgênio (AR). Este trabalho teve por objetivo caracterizar o papel funcional do ncRNA DD3 no CaP através da alteração de sua expressão na linhagem celular LNCaP, bem como avaliar seu envolvimento na via do AR. A função deste transcrito foi avaliada através da redução de sua expressão em células LNCaP utilizando RNAs de interferência específicos. Ensaios de viabilidade celular foram analisados por coloração com cristal violeta e azul de tripan e a avaliação da proporção de núcleos apoptóticos por marcação de núcleo com DAPI. Centrifugações fracionadas foram utlizadas para caracterizar as frações celulares em que o DD3 está localizado. As células LNCaP com DD3 silenciado apresentaram redução da viabilidade celular e aumento da proporção de núcleos picnóticos, indicativos de células em apoptose. O tratamento da LNCaP com o androgênio DHT aumentou significativamente a expressão do DD3, sendo esta ativação revertida pelo anti-androgênio flutamida, demonstrando que a indução da expressão do DD3 é mediada por esta via. A expressão de genes de resposta ao AR foi alterada quando a expressão do DD3 foi diminuída, indicando ser o DD3 um regulador da expressão destes genes. A tentativa de amplificar o transcrito completo do DD3 associada com predições de estruturas secundárias evidenciou que o DD3 pode ser processado em transcritos menores. Nossos dados indicam que este ncRNA é expresso majoritariamente no núcleo, em vesículas e ribossomos. Em conjunto, estes dados sugerem que o DD3 regula a expressão de genes envolvidos com a sobrevivência de células de CaP. Sugerem também, que após ser processado, deverá exercer funções relacionadas ao controle da expressão gênica, principalmente no núcleo e em vesículas...

The DD3 gene corresponds to a non-coding RNA (ncRNA) specifically expressed in prostate tissues. Its role as a marker for prostate cancer (CaP) diagnosis is well established, although very few is currently known about its role on PCa biology as well about its involvement in the androgen receptor (AR) pathway. The purpose of this work was to characterize the functional role of DD3 ncRNA in PCa using LNCaP cells as a model and to evaluate its involvement in the AR pathway. The role of DD3 transcript was evaluated using gene knockdown assays in LNCaP cells using DD3 specific siRNAs. Cellular viability was analyzed by trypan blue exclusion and crystal violet assays and the evaluation of apoptotic nuclei was performed by DAPI staining. Differential centrifugation and RT-PCR assays were used to characterize the cellular fractions in which DD3 is expressed. LNCaP cells transfected with siRNA-DD3 demonstrated a decrease in cell viability and an increase in the proportion of pyknotic nuclei, which was indicative of cells undergoing apoptosis. LNCaP treatment with DHT androgen significantly activated DD3 expression by 11-fold, indicating that DD3 is regulated by the AR activation. Once no full length DD3 transcript could be amplified, in addition to observed predicted secondary structures in this transcript, we suggest that DD3 can be processed in minor transcripts. Our data indicate that this ncRNA is mostly expressed in the nucleus, cellular vesicles and ribosomes. Altogether, these data suggest that DD3 is a transcriptional regulator of genes involved on PCa cell survival. It also suggest that, after being processed, DD3 can perform its role on gene regulation mainly in the nucleus or cellular vesicles. Hence, DD3 could correspond to an important therapeutical target for PCa, especially for treatment of hormone refractory PCa. The results generated by this study provide the basis for a better knowledgement about signaling pathways activated by AR !"#$%&%'()) * and on the regulation of genes involved on this pathway, such as the ncRNA DD3

The novel prostate cancer antigen 3 (PCA3) biomarker

PCA3 is a prostate specific, nonprotein coding RNA that is significantly over expressed in prostate cancer, without any correlation to prostatic volume and/or other prostatic diseases (e.g. prostatitis). It can now easily be measured in urine with a novel transcription-mediated amplification based test. Quantification of PCA3 mRNA levels can predict the outcome of prostatic biopsies with a higher specificity rate in comparison to PSA. Several studies have demonstrated that PCA3 can be used as a prognostic marker of prostate cancer, especially in conjunction with other predictive markers. Novel PCA3-based nomograms have already been introduced into clinical practice. PCA3 test may be of valuable help in several PSA quandary situations such as negative prostatic biopsies, concomitant prostatic diseases, and active surveillance. Results from relevant clinical studies, comparative with PSA, are warranted in order to confirm the perspective of PCA3 to substitute PSA.