Virginie Vlaeminck-Guillem

Urinary Prostate Cancer 3 Test: Toward the Age of Reason?

The prostate cancer 3 (PCA3) gene was discovered in 1999, on the basis of differential expression between cancer and noncancerous prostate tissue. Including the first study published in 2003, 11 clinical studies have evaluated its utility for the diagnosis of prostate cancer by measuring the number of PCA3 RNA copies in urine enriched with prostate cells. Although the sensitivity of the PCA3 test was less than that of serum prostate-specific antigen (PSA), its specificity appeared to be much better, particularly in patients with a previous negative biopsy. Recent studies also have suggested that this test could be used to predict cancer prognosis.

TM4SF1, a novel primary androgen receptor target gene over-expressed in human prostate cancer and involved in cell migration

The Androgen Receptor (AR) plays a key role in controlling prostate gland homeostasis and contributes to prostate carcinogenesis. The identification of its target genes should provide new candidates that may be implicated in cancer initiation and progression.

Urinary PCA3 Score Predicts Prostate Cancer Multifocality

PURPOSE The urinary PCA3 gene test has proved helpful for deciding whether to (re)biopsy to diagnose prostate cancer. We searched for pathological features that influence the shedding of PCA3 producing prostate cancer cells in urine after digital rectal examination. MATERIALS AND METHODS Included in our study were 102 patients with an informative PCA3 score on the Progensa® PCA3 assay who underwent radical prostatectomy. Correlations were evaluated between PCA3 score and histopathological factors on prostatectomy, including tumor site in the prostate and the number of cancer foci. RESULTS PCA3 score significantly correlated with total tumor volume in prostatectomy specimens (p <0.001) but not with prostatectomy Gleason score or pathological stage. PCA3 score positively correlated with apical and basal invasion, and with bilaterality and multifocality. On multivariate analysis multifocality was an independent factor influencing PCA3 score (p = 0.012). CONCLUSIONS Site in the prostate gland and the number of cancer foci may explain the observed PCA3 score variation in patients operated on for prostate cancer. The PCA3 test could be helpful in preoperatively selecting patients with unifocal and unilateral cancer who could benefit from active surveillance or focal therapy.

Comparative Evaluation of Urinary PCA3 and TMPRSS2: ERG Scores and Serum PHI in Predicting Prostate Cancer Aggressiveness

It has been suggested that urinary PCA3 and TMPRSS2:ERG fusion tests and serum PHI correlate to cancer aggressiveness-related pathological criteria at prostatectomy. To evaluate and compare their ability in predicting prostate cancer aggressiveness, PHI and urinary PCA3 and TMPRSS2:ERG (T2) scores were assessed in 154 patients who underwent radical prostatectomy for biopsy-proven prostate cancer. Univariate and multivariate analyses using logistic regression and decision curve analyses were performed. All three markers were predictors of a tumor volume ≥0.5 mL. Only PHI predicted Gleason score ≥7. T2 score and PHI were both independent predictors of extracapsular extension (≥pT3), while multifocality was only predicted by PCA3 score. Moreover, when compared to a base model (age, digital rectal examination, serum PSA, and Gleason sum at biopsy), the addition of both PCA3 score and PHI to the base model induced a significant increase (+12%) when predicting tumor volume >0.5 mL. PHI and urinary PCA3 and T2 scores can be considered as complementary predictors of cancer aggressiveness at prostatectomy.

PCA3 and PCA3-Based Nomograms Improve Diagnostic Accuracy in Patients Undergoing First Prostate Biopsy

While now recognized as an aid to predict repeat prostate biopsy outcome, the urinary PCA3 (prostate cancer gene 3) test has also been recently advocated to predict initial biopsy results. The objective is to evaluate the performance of the PCA3 test in predicting results of initial prostate biopsies and to determine whether its incorporation into specific nomograms reinforces its diagnostic value. A prospective study included 601 consecutive patients addressed for initial prostate biopsy. The PCA3 test was performed before ≥12-core initial prostate biopsy, along with standard risk factor assessment. Diagnostic performance of the PCA3 test was evaluated. The three available nomograms (Hansen’s and Chun’s nomograms, as well as the updated Prostate Cancer Prevention Trial risk calculator; PCPT) were applied to the cohort, and their predictive accuracies were assessed in terms of biopsy outcome: the presence of any prostate cancer (PCa) and high-grade prostate cancer (HGPCa). The PCA3 score provided significant predictive accuracy. While the PCPT risk calculator appeared less accurate; both Chun’s and Hansen’s nomograms provided good calibration and high net benefit on decision curve analyses. When applying nomogram-derived PCa probability thresholds ≤30%, ≤6% of HGPCa would have been missed, while avoiding up to 48% of unnecessary biopsies. The urinary PCA3 test and PCA3-incorporating nomograms can be considered as reliable tools to aid in the initial biopsy decision.

Chronic prostatitis does not influence urinary PCA3 score

The influence of chronic prostatitis on serum PSA level is well known. Whether it also influences potential new biomarkers of prostate cancer (PCa) has to be determined. We conducted a prospective study to evaluate the effect of chronic prostatitis on the PCa urinary marker PCA3.

Differentially expressed androgen-regulated genes in androgen-sensitive tissues reveal potential biomarkers of early prostate cancer.

Background Several data favor androgen receptor implication in prostate cancer initiation through the induction of several gene activation programs. The aim of the study is to identify potential biomarkers for early diagnosis of prostate cancer (PCa) among androgen-regulated genes (ARG) and to evaluate comparative expression of these genes in normal prostate and normal prostate-related androgen-sensitive tissues that do not (or rarely) give rise to cancer. Methods ARG were selected in non-neoplastic adult human prostatic epithelial RWPE-1 cells stably expressing an exogenous human androgen receptor, using RNA-microarrays and validation by qRT-PCR. Expression of 48 preselected genes was quantified in tissue samples (seminal vesicles, prostate transitional zones and prostate cancers, benign prostatic hypertrophy obtained from surgical specimens) using TaqMan® low-density arrays. The diagnostic performances of these potential biomarkers were compared to that of genes known to be associated with PCa (i.e. PCA3 and DLX1). Results and Discussion By crossing expression studies in 26 matched PCa and normal prostate transitional zone samples, and 35 matched seminal vesicle and PCa samples, 14 genes were identified. Similarly, 9 genes were overexpressed in 15 benign prostatic hypertrophy samples, as compared to PCa samples. Overall, we selected 8 genes of interest to evaluate their diagnostic performances in comparison with that of PCA3 and DLX1. Among them, 3 genes: CRYAB, KCNMA1 and SDPR, were overexpressed in all 3 reference non-cancerous tissues. The areas under ROC curves of these genes reached those of PCA3 (0.91) and DLX1 (0.94). Conclusions We identified ARG with reduced expression in PCa and with significant diagnostic values for discriminating between cancerous and non-cancerous prostatic tissues, similar that of PCA3. Given their expression pattern, they could be considered as potentially protective against prostate cancer. Moreover, they could be complementary to known genes overexpressed in PCa and included along with them in multiplex diagnostic tools.

Src: Marker or Actor in Prostate Cancer Aggressiveness

A key question for urologic practitioners is whether an apparently organ-confined prostate cancer (PCa) is actually aggressive or not. The dilemma is to specifically identify among all prostate tumors the very aggressive high-grade cancers that will become life-threatening by developing extra-prostatic invasion and metastatic potential and the indolent cancers that will never modify a patient’s life expectancy. A choice must be made between several therapeutic options to achieve the optimal personalized management of the disease that causes as little harm as possible to patients. Reliable clinical, biological, or pathological markers that would enable distinctions to be made between aggressive and indolent PCas in routine practice at the time of initial diagnosis are still lacking. The molecular mechanisms that explain why a PCa is aggressive or not are also poorly understood. Among the potential markers and/or actors in PCa aggressiveness, Src and other members of the Src kinase family, are valuable candidates. Activation of Src-dependent intracellular pathways is frequently observed in PCa. Indeed, Src is at the cross-roads of several pathways [including androgen receptor (AR), TGFbeta, Bcl-2, Akt/PTEN or MAPK, and ERK …], and is now known to influence some of the cellular and tissular events that accompany tumor progression: cell proliferation, cell motility, invasion, epithelial-to-mesenchymal transition, resistance to apoptosis, angiogenesis, neuroendocrine differentiation, and metastatic spread. Recent work even suggests that Src could also play a part in PCa initiation in coordination with the AR. The aim of this review is to gather data that explore the links between the Src kinase family and PCa progression and aggressiveness.

TRα receptor mutations extend the spectrum of syndromes of reduced sensitivity to thyroid hormone.

Since 2012, eight different abnormalities have been described in the THRA gene (encoding the TRα1 thyroid hormone receptor) of 14 patients from 9 families. These mutations induce a clinical phenotype (resistance to thyroid hormone type α) associating symptoms of untreated mild congenital hypothyroidism and a near-normal range of free and total thyroid hormones and TSH (the T4/T3 ratio is nevertheless usually low). The phenotype can diversely include short stature (due to growth retardation), dysmorphic syndrome (face and limb extremities), psychoneuromotor disorders, constipation and bradycardia. The identified genetic abnormalities are located within the ligand-binding domain and result in defective T3 binding, an abnormally strong interaction with corepressors and a dominant negative activity against still functional receptors. The identification of patients with consistent phenotypes and the underlying mutations are warranted to better delineate the spectrum of the syndromes of reduced sensitivity to thyroid hormone.

Intérêt du test urinaire PCA3 dans la décision de biopsie prostatique : l’expérience du Centre hospitalier Lyon-Sud

The poor specificity of diagnostic strategy for prostate cancer (digital rectal examination and seric PSA) induces both a great number of useless prostate biopsies and diagnosis of non evolutive cancers. A urinary test (Progensa PCA3(®), Gen-Probe) measuring the expression of PCA3, a prostate cancer-specific gene, has recently be proposed to indicate re-biopsy. The aim of this prospective study was to evaluate diagnostic value of urinary PCA3 test for prostate cancer. In the urines of 245 patients submitted to prostate biopsy, expression of the PCA3 gene was measured and reported to that of PSA to calculate PCA3 score using a method amplifying and detecting RNA. Patients with informative samples (98%) were classified depending of the presence (n = 126) or absence (n = 114) of cancer tissue on biopsies. The median PCA3 score was significantly higher in the group with positive biopsies (p < 0.0001). Area under ROC curve was 0.70 for PCA3 as compared to that of PSA (0.53) and free/total PSA ratio (0.65). At the best threshold of 38, PCA3 test had a 59%-sensitivity and a 72%-specificity, as compared to 66% and 32% for total PSA (threshold 4 ng/mL) and 81% and 28% for free/total PSA ratio (threshold 25%). These performances were maintained in patients with seric PSA within the grey zone (4-10 ng/mL) and those with previous prostate biopsies. This study confirms the clinical value of PCA3 urinary test in helping decision for biopsies in patients with suspected prostate cancer.