Adriano Nesrallah

miR-21 may acts as an oncomir by targeting RECK, a matrix metalloproteinase regulator, in prostate cancer

BackgroundPrognosis of prostate cancer (PCa) is based mainly in histological aspects together with PSA serum levels that not always reflect the real aggressive potential of the neoplasia. The micro RNA (miRNA) mir-21 has been shown to regulate invasiveness in cancer through translational repression of the Metaloproteinase (MMP) inhibitor RECK. Our aim is to investigate the levels of expression of RECK and miR-21 in PCa comparing with classical prognostic factors and disease outcome and also test if RECK is a target of miR-21 in in vitro study using PCa cell line.Materials and methodsTo determine if RECK is a target of miR-21 in prostate cancer we performed an in vitro assay with PCa cell line DU-145 transfected with pre-miR-21 and anti-miR-21. To determine miR-21 and RECK expression levels in PCa samples we performed quantitative real-time polymerase chain reaction (qRT-PCR).ResultsThe in vitro assays showed a decrease in expression levels of RECK after transfection with pre-miR-21, and an increase of MMP9 that is regulated by RECK compared to PCa cells treated with anti-miR-21. We defined three profiles to compare the prognostic factors. The first was characterized by miR-21 and RECK underexpression (Nu2009=u200925) the second was characterized by miR-21 overexpression and RECK underexpression (Nu2009=u200912), and the third was characterized by miR-21 underexpression and RECK overexpression (Nu2009=u200916). From men who presented the second profile (miR-21 overexpression and RECK underexpression) 91.7% were staged pT3. For the other two groups 48.0%, and 46.7% of patients were staged pT3 (pu2009=u20090.025).ConclusionsOur results demonstrate RECK as a target of miR-21. We believe that miR-21 may be important in PCa progression through its regulation of RECK, a known regulator of tumor cell invasion.

Perineural invasion detection in prostate biopsy is related to recurrence-free survival in patients submitted to radical prostatectomy.

OBJECTIVEnPerineural invasion (PNI) is detected in almost 20% of prostate biopsies and has been related to worse prognostic factors in radical prostatectomy (RP) specimens and lower disease-free survival rates. The aim of this study was to evaluate the importance of PNI during periods of extended prostate biopsies and to determine the value of this preoperative parameter as a predictor of pathologic findings in surgical specimens and in biochemical recurrence.nnnMATERIALS AND METHODSnBetween 2001 and 2009, 599 prostate biopsies and their respective RP specimens were examined in our laboratory. The RP specimens were always examined completely. The mean age of the patients was 61 years, and the mean PSA was 6.4 ng/mL. The mean and median number of biopsy cores obtained was 14.4 and 14, respectively. PNI was identified in 105 biopsies (17.5%). We studied the ability of PNI in prostate biopsies to determine the tumor stage in surgical specimens and the relationship of PNI with biochemical recurrence during a mean follow-up time of 51.4 months.nnnRESULTSnThe presence of PNI in prostate biopsies was observed in older patients (63 vs. 61 years old, P = 0.008). All of the prognostic factors determined for the RP specimens were significantly worse in patients with PNI compared with those without PNI. PNI was strongly associated with a higher pathologic stage (87% specificity, 40% sensitivity, odds ratio 4.8). Stage pT3 prostatic cancer was determined in 46 (43.8%) of 105 patients with PNI on biopsy compared to 69 (14%) of 494 patients without PNI (P = 0.01). Fifty-six (19.6%) patients had a biochemical recurrence, and PNI correlated significantly with PSA recurrence. A Kaplan-Meier analysis revealed a significant difference in recurrence-free survival between patients with and without PNI (45% vs. 53%, respectively, P = 0.021, log-rank test = 0.19).nnnCONCLUSIONnPNI is an important morphologic preoperative predictor of the pathologic stage as well as biochemical recurrence and must always be mentioned when adenocarcinoma is diagnosed on prostate biopsies.

Are we able to correctly identify prostate cancer patients who could be adequately treated by focal therapy

INTRODUCTION AND OBJECTIVEnBecause of the improvements on detection of early stage prostate cancer over the last decade, focal therapy for localized prostate cancer (PC) has been proposed for patients with low-risk disease. Such treatment would allow the control of cancer, thereby diminishing side effects, such as urinary incontinence and sexual dysfunction, which have an enormous impact on quality of life. The critical issue is whether it is possible to preoperatively predict clinically significant unifocal or unilateral prostate cancer with sufficient accuracy. Our aim is to determine whether there is any preoperative feature that can help select the ideal patient for focal therapy.nnnMATERIAL AND METHODSnA total of 599 patients who underwent transrectal ultrasound (TRUS)-guided prostate biopsy followed by radical prostatectomy to treat PC were examined in our laboratory between 2001 and 2009. We established very restricted criteria to select patients with very-low-risk disease for whom focal therapy would be suitable (only 1 biopsy core positive, tumor no larger than 80% of a single core, no perineural invasion, PSA serum level < 10 ng/ml, Gleason score < 7 and clinical stage T1c, T2a-b). We defined 2 groups of patients who would be either adequately treated or not treated by focal therapy. The primary endpoint was the evaluation of preoperative features in order to identify which parameters should be considered when choosing good candidates for focal therapy.nnnRESULTSnFifty-six out of 599 patients met our criteria. The mean age was 59 years, and the mean number of biopsy cores was 14.4. Forty-seven (83.9%) were staged T1c, and 9 (16.1%) were staged T2a-b. Forty-four (78.6%) patients could be considered to have been adequately treated by focal therapy, and 12 (21.4%) could not. There was no statistical difference between the 2 groups considering age, clinical stage, PSA levels, Gleason score, and tumor volume in the biopsy. All 12 patients who could be considered inadequately treated had a bilateral, significant secondary tumor, 58.3% had Gleason ≥ 7, and 25% were staged pT3.nnnCONCLUSIONnAlthough focal therapy might be a good option for patients with localized prostate cancer, we are so far unable to select which of them would benefit from it based on preoperative data, even using very restricted criteria, and a considerable proportion of men would still be left undertreated.

The role of extended prostate biopsy on prostate cancer detection rate: a study performed on the bench

INTRODUCTIONnThe aim of this prospective study was to compare the advantage of performing prostate biopsy with a greater number of cores using the classic sextant procedure, with the aim of reducing false negative results.nnnMATERIALS AND METHODSn100 prostates were acquired from consecutive radical prostatectomies performed by the same surgeon. Fourteen cores were obtained on the bench following surgery using an automatic pistol with an 18-gauge needle. Six of these cores were obtained according to the sextant technique, as described by Hodge et al.; with the addition of a further three lateral cores from each lobe and one from the bilateral transition zone. The whole gland and the fragments were assessed by the same pathologist. An analysis of the frequency of the cancers identified in the cores of the sextant and the extended biopsies was undertaken and the results evaluated comparatively. The chi-square test was used for the comparative analysis of the cancer detection rate, according to the technique used.nnnRESULTSnWhen 6 cores were removed, the positive cancer rate was 75%, which was increased to 88% when 14 cores were (p < 0.001). The withdrawal of 14 cores resulted in a significant 13% (95% CI [5%-21%]) increase in the positive rate of cancer detection.nnnCONCLUSIONnExtended biopsy, with the removal of 14 cores, is more efficient than the sextant procedure in improving the rate of prostate cancer detection.

Socioeconomic status is an independent predictor of biochemical recurrence among patients with prostate cancer who undergo radical prostatectomy

PURPOSE: Socioeconomic status (SES) may influence cancer characteristics and behavior in several aspects. We analyzed PCa characteristics and behavior among low income uninsured men, and compare them to high income patients with health insurance in a developing country. MATERIALS AND METHODS: A retrospective case-control study was performed on 934 patients with clinically localized PCa who underwent radical prostatectomy between March, 1999 and July, 2009. Patients were divided in two groups, according to their SES. In group 1 (n=380), all had low income, low educational levels and couldnt afford medical insurance. In group 2 (n=554), all had higher income, higher education and had medical insurance. RESULTS: Patients from group 1 were older, had higher Gleason scores, higher rates of seminal vesicle and bladder neck involvement. The Kaplan Meier disease-free survival curve demonstrated that after a follow-up of four years, about 50% of uninsured patients had biochemical recurrence, versus 21% of insured patients (Log rank test: p < 0.001). A multivariate Cox regression analysis for the risk of disease recurrence demonstrated that only PSA levels, Gleason score, seminal vesicle involvement and SES were statistically significant variables. Patients with a low SES presented 1.8 times the risk of recurrence as compared to patients with a high SES. CONCLUSIONS: Patients with low SES were older, presented more aggressive PCa characteristics and a high rate of disease recurrence. A low SES constituted an independent predictor for disease recurrence.

Salvage Radical Prostatectomy: An Alternative Treatment for Local Recurrence of Radioresistant Cancer

OBJECTIVESnThe treatment of recurrent prostate cancer after radiotherapy or brachytherapy through radical prostatectomy has been little indicated due to the concern over the procedures morbidity. We present the experience of our service with postradiotherapy radical prostatectomy.nnnMATERIALS AND METHODSnBetween 1996 and 2002, 9 patients submitted to radiotherapy due to prostate cancer were treated with salvage surgery for locally recurrent disease. All patients had a biopsy of the prostate confirming the tumor recurrence, increase in the PSA levels and staging without evidence of a systemic disease. We have assessed the morbidity and the recurrence-free survival rate after salvage radical prostatectomy.nnnRESULTSnPreradiotherapy PSA varied from 6.2 to 50 ng/mL (mean 17.3) and clinical staging T1, T2 and T3 in 33.3%, 44.4% and 22.2% of the patients respectively. The interval for the biopsy after conforming external beam radiotherapy or brachytherapy varied from 8 to 108 months (median: 36). Four patients received antiandrogenic therapy neoadjuvant to the surgery with a mean of 7 months (1-48) after radiotherapy. From the six patients potent before the surgery, three have presented erectile dysfunction. Urinary incontinence as well as bladder neck sclerosis occurred in two patients (22.2%). Biochemical recurrence occurred in two individuals (22.2%) 12 months after the surgery. Biochemical recurrence-free survival rate was 77.8% with median follow-up time of 30 months (8-102).nnnCONCLUSIONnSalvage radical prostatectomy is a safe and effective alternative for the treatment of locally recurrent prostate cancer after radiotherapy and brachytherapy.

The use of immunohistochemistry for diagnosis of prostate cancer

PURPOSEnAtypical glands (ASAP) are diagnosed in 5.0% of prostate biopsies, and cancer identification in a rebiopsy is higher than 40.0%. The use of antibodies to mark basal cells is currently a common practice, in order to avoid rebiopsies. There has been no reported study that has reviewed characteristics of radical prostatectomies (RPs) when immunohistochemistry (IHC) was necessary for definitive diagnosis.nnnMATERIALS AND METHODSnOut of 4127 biopsies examined from 2004 to 2008, 144 (3.5%) were diagnosed with ASAP. IHC was performed using antibody anti-34ΒE12 and p63. The results of surgical specimens of 27 patients treated by RP after the diagnosis of prostate cancer (PC) was made using IHC (Group 1) were compared with 1040 patients where IHC was not necessary (Group 2).nnnRESULTSnIHC helped to diagnose PC in 103 patients (71.5%). Twenty-seven (26.2%) underwent RP. In Group 1, two (7.4%) adenocarcinomas were insignificant versus 29 (2.9%) for Group 2. Patients from Group 1 were younger (p = 0.039), had lower Gleason scores (GS) (p < 0.001), lower percentage of Gleason pattern 4 (p < 0.001), and smaller tumors (p < 0.001).nnnCONCLUSIONnThe use of IHC did not lead to diagnosis of insignificant tumors as illustrated by absence of differences in pathological stage or positive surgical margins in men submitted to RP. Therefore, our results suggest that this modality should be routinely used for a borderline biopsy and ASAP cases.

Preoperative determination of prostate cancer tumor volume: analysis through biopsy fragments

OBJECTIVEnPreoperative determination of prostate cancer (PCa) tumor volume (TV) is still a big challenge. We have assessed variables obtained in prostatic biopsy aiming at determining which is the best method to predict the TV in radical prostatectomy (RP) specimens.nnnMATERIALS AND METHODSnBiopsy findings of 162 men with PCa submitted to radical prostatectomy were revised. Preoperative characteristics, such as PSA, the percentage of positive fragments (PPF), the total percentage of cancer in the biopsy (TPC), the maximum percentage of cancer in a fragment (MPC), the presence of perineural invasion (PNI) and the Gleason score were correlated with postoperative surgical findings through an univariate analysis of a linear regression model.nnnRESULTSnThe TV correlated significantly to the PPF, TPC, MPC, PSA and to the presence of PNI (p < 0.001). However, the Pearson correlation analysis test showed an R2 of only 24%, 12%, 17% and 9% for the PPF, TPC, MPC, and PSA respectively. The combination of the PPF with the PSA and the PNI analysis showed to be a better model to predict the TV (R2 of 32.3%). The TV could be determined through the formula: Volume = 1.108 + 0.203 x PSA + 0.066 x PPF + 2.193 x PNI.nnnCONCLUSIONSnThe PPF seems to be better than the TPC and the MPC to predict the TV in the surgical specimen. Due to the weak correlation between those variables and the TV, the PSA and the presence of PNI should be used together.

Tumor banks: the cornerstone of basic research in urology

PURPOSEnTumor banks have the primary responsibility for collecting, cataloging, storing and disseminating samples of tissues, cells and fluids, which are used by researchers to identify diagnostic molecular markers, prognostic indicators and therapeutic targets. The objective of this review was to describe a simple, reliable and reproducible protocol for obtaining and storing samples of urological tumors.nnnMATERIALS AND METHODSnUrogenital tumor tissues were collected by the surgeons from the Urology Division of University of Sao Paulo Medical School. The obtained surgical specimens were immediately placed in liquid nitrogen, dry ice or in a tube containing RNAlater, and then stored by cryopreservation (-80 degrees C). A mirror fragment was fixed in 10% formalin processed routinely and embedded in Paraplast.nnnRESULTSnWe developed a protocol for the collection, cataloging, storage, conservation and use of tumor samples. During a period of one year the Urological Tumor Bank of the Urology Division stored 274 samples of prostate, bladder, kidney, penis and testicle tumors of different histological types, 74 urine and 271 serum samples.nnnCONCLUSIONSnHaving biological materials characterized and available along with the clinical patient information provides an integrated portrait of the patients and their diseases facilitating advances in molecular biology. It also promotes the development of translational research improving methods of diagnosis and cancer treatment.

The accuracy of pathological data for the prediction of insignificant prostate cancer

INTRODUCTIONnThe widespread screening programs prompted a decrease in prostate cancer stage at diagnosis, and active surveillance is an option for patients who may harbor clinically insignificant prostate cancer (IPC). Pathologists include the possibility of an IPC in their reports based on the Gleason score and tumor volume. This study determined the accuracy of pathological data in the identification of IPC in radical prostatectomy (RP) specimens.nnnMATERIALS AND METHODSnOf 592 radical prostatectomy specimens examined in our laboratory from 2001 to 2010, 20 patients harbored IPC and exhibited biopsy findings suggestive of IPC. These biopsy features served as the criteria to define patients with potentially insignificant tumor in this population. The results of the prostate biopsies and surgical specimens of the 592 patients were compared.nnnRESULTSnThe twenty patients who had IPC in both biopsy and RP were considered real positive cases. All patients were divided into groups based on their diagnoses following RP: true positives (n = 20), false positives (n = 149), true negatives (n = 421), false negatives (n = 2). The accuracy of the pathological data alone for the prediction of IPC was 91.4%, the sensitivity was 91% and the specificity was 74%.nnnCONCLUSIONnThe identification of IPC using pathological data exclusively is accurate, and pathologists should suggest this in their reports to aid surgeons, urologists and radiotherapists to decide the best treatment for their patients.