Roberta Lucianò

Evaluation of positive surgical margins in patients undergoing robot-assisted and open radical prostatectomy according to preoperative risk groups

OBJECTIVES Recent studies showed that robot-assisted radical prostatectomy (RARP) represents an oncologically safe procedure in patients with prostate cancer (PCa), where the rate of positive surgical margins (PSMs) might be lower in patients treated with RARP as compared with that of those undergoing the open approach (open RP [ORP]). The aim of this study is to analyze the rate of PSMs according to preoperative risk groups in a large cohort of patients treated with RARP and ORP in a single institution with standardized surgical technique and pathological examination. MATERIALS AND METHODS We evaluated 6,194 consecutive patients with PCa undergoing either ORP (71.1%) or RARP (28.9%) between 1992 and 2014. Logistic regression analyses were used to test the association between type of surgery and PSMs in each preoperative risk group (low vs. intermediate vs. high) after adjusting for confounders. RESULTS Overall, 21.6% patients had PSMs. RARP was associated with a lower rate of PSMs in low-risk (11.5 vs. 15.4%, P = 0.01), intermediate-risk (18.9 vs. 23.5%, P = 0.008), and high-risk patients (19.7 vs. 30.1%, P<0.001). In multivariable analyses, after stratification according to risk group categories, no difference in PSMs between RARP and ORP was observed for low-risk (odds ratio [OR] = 0.87, P = 0.46) and intermediate-risk patients (OR = 0.84, P = 0.19). Conversely, RARP was associated with lower odds of PSMs in high-risk patients (OR = 0.69, P = 0.04). Similar results were observed when our analyses were repeated after accounting for pathological characteristics, in patients treated between 2006 and 2014 and in a cohort of men treated by high-volume surgeons (all P≤ 0.03). CONCLUSIONS The introduction of RARP at our institution led to a significant reduction in the risk of PSMs in patients with PCa with high-risk disease.

The Microbiome of the Prostate Tumor Microenvironment

BACKGROUND The advent of molecular-based methods of identification and characterization of complex microbial populations has led to a new era of microbial discovery. A detailed and comprehensive analysis of the microbial ecosystem of the pathologic and healthy prostate tissues has not been yet reported. OBJECTIVES To characterize the microbiome possibly associated to the pathologic prostate microenvironment. DESIGN, SETTING, AND PARTICIPANTS The microbiome profile of tumor, peri-tumor, and nontumor tissues was assessed on 16 radical prostatectomy-specimens. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Microbiome analysis was assessed by massive ultradeep pyrosequencing. Bacteria load was expressed as a percentage of the total number of bacteria. The statistical significance of differences among specimen-groups was tested with Friedmans test (Dunn posthoc test) and Wilcoxon rank-sum test. RESULTS AND LIMITATIONS Three phyla, six classes, nine orders, 14 families, and 11 genera were above the set threshold value of 1%, respectively. Significant differences in specific microbial populations among tumor/peri-tumor and nontumor prostate specimens were observed at certain taxonomic levels. Among genera, Propionibacterium spp. were the most abundant. Staphylococcus spp. were more represented in the tumor/peri-tumor tissues (p<0.05). The restricted number of specimens represents a potential limitation. CONCLUSIONS The prostate contains a plethora of bacteria, which set themselves within the gland with a distribution dependent on the nature of the tissue, thus suggesting a possible pathophysiological correlation between the composition of the local microbial niche and the presence of the tumor itself. Future studies will help to clarify the role of these specific bacteria and their potential to be exploited as new biomarkers. PATIENT SUMMARY The pathological prostate is populated by specific microbial populations, whose distribution varies according to the nature of the tissue. This finding opens interesting perspectives for the identification of novel therapeutic approaches and biomarkers.

Mesenchymal stem cells expressing therapeutic genes induce autochthonous prostate tumour regression

Mesenchymal stem cells (MSC) as vehicles of therapeutic genes represent a unique tool to activate drugs within a neoplastic mass due to their property to home and engraft into tumours. In particular, MSC expressing the cytosine deaminase::uracil phosphoribosyltransferase (CD-MSC) have been previously demonstrated to inhibit growth of subcutaneous prostate cancer xenografts thanks to their ability to convert the non-toxic 5-fluorocytosine into the antineoplastic 5-fluorouracil. Since both the immune system and the tumour microenvironment play a crucial role in directing cancer progression, in order to advance towards clinical applications, we tested the therapeutic potential of this approach on animal models that develop autochthonous prostate cancer and preserve an intact immune system. As cell vectors, we employed adipose-tissue and bone-marrow MSC. CD-MSC toxicity on murine prostate cancer cells and tumour tropism were verified in vitro and ex-vivo before starting the preclinical studies. Magnetic Resonance Imaging was utilised to follow orthotopic tumour progression. We demonstrated that intravenous injections of CD-MSC cells, followed by intraperitoneal administration of 5-fluorocytosine, caused tumour regression in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model, which develops aggressive and spontaneous prostate cancer. These results add new insights to the therapeutic potential of specifically engineered MSC in prostate cancer disease.

IL-23 secreted by myeloid cells drives castration-resistant prostate cancer

Patients with prostate cancer frequently show resistance to androgen-deprivation therapy, a condition known as castration-resistant prostate cancer (CRPC). Acquiring a better understanding of the mechanisms that control the development of CRPC remains an unmet clinical need. The well-established dependency of cancer cells on the tumour microenvironment indicates that the microenvironment might control the emergence of CRPC. Here we identify IL-23 produced by myeloid-derived suppressor cells (MDSCs) as a driver of CRPC in mice and patients with CRPC. Mechanistically, IL-23 secreted by MDSCs can activate the androgen receptor pathway in prostate tumour cells, promoting cell survival and proliferation in androgen-deprived conditions. Intra-tumour MDSC infiltration and IL-23 concentration are increased in blood and tumour samples from patients with CRPC. Antibody-mediated inactivation of IL-23 restored sensitivity to androgen-deprivation therapy in mice. Taken together, these results reveal that MDSCs promote CRPC by acting in a non-cell autonomous manner. Treatments that block IL-23 can oppose MDSC-mediated resistance to castration in prostate cancer and synergize with standard therapies.IL-23 produced by myeloid-derived suppressor cells regulates castration resistance in prostate cancer by sustaining androgen receptor signalling.

Incidence and effect of variant histology on oncological outcomes in patients with bladder cancer treated with radical cystectomy

INTRODUCTION We sought to describe incidence of histological variants after radical cystectomy (RC) due to bladder cancer (BCa). Moreover, we investigated survival outcomes accounting for this parameter. METHODS We retrospectively evaluated data from 1,067 patients with BCa treated with RC between 1990 and 2013 at a single tertiary care referral center. All specimen were evaluated by dedicated uropathologists. Univariable and multivariable Cox regression analyses tested the effect of different histopathological variant on recurrence, cancer-specific mortality (CSM), and overall mortality (OM) after accounting for all available confounders. RESULTS Of 1,067 patients, 729 (68.3%) harbored pure urothelial BCa while 338 (31.7%) were found to have a variant. Considering uncommon variants, 21 (2.0%) were sarcomatoid, 10 (0.9%) lymphoepitelial, 19 (1.8%) small cell, 109 (10.2%) squamous, 89 (8.3%) micropapillary, 23 (2.2%) glandular, 34 (3.2%) mixed variants, and 33 (3.1%) were found with other types of variants. With a median follow-up of 6.2 years, 343 recurrence, 365 CSM, and 451 OM were recorded, respectively. At multivariable Cox regression analyses, the presence of small cell variant was associated with higher recurrence (hazard ratio [HR] = 3.47, P<0.001), CSM (HR = 3.30, P<0.04), and OM (HR = 2.97, P<0.003) as compared with pure urothelial cancer. Conversely, no survival differences were recorded considering other histological variants (all P> 0.1). CONCLUSION Our study confirms that histological variant is not an infrequent event at RC specimen. However, in our single-center series, only patients found with small cell variant were associated with a negative effect on survival after RC.

PD-L1 Expression and CD8+ T-cell Infiltrate are Associated with Clinical Progression in Patients with Node-positive Prostate Cancer

Prostate cancer (PCa) patients with lymph node invasion at radical prostatectomy are at higher risk of tumor recurrence and receive immediate androgen deprivation therapy (ADT). While approximately 30% of these patients do not experience recurrence, others experience disease recurrence despite ADT, and currently no biomarkers can accurately identify them. We analyzed tumors from 51 patients with node-positive prostate cancer using immunohistochemistry to investigate whether expression of the immune checkpoint ligand PD-L1 by tumor cells or the density of CD8+ or CD20+ cells are associated with clinical progression. Patients with at least 1% PD-L1+ tumor cells had shorter metastasis-free survival than those with PD-L1- tumors (p=0.008, log-rank test). Univariate Cox regression showed that patients with PD-L1+ tumors had almost four times the risk of experiencing distant metastases than those with PD-L1- tumors (hazard ratio 3.90). In addition, we found that PD-L1 expression was significantly associated with CD8+ T-cell density, but not with CD20+ B-cell density. While these results need to be confirmed in larger studies, they show that PD-L1 and CD8 may be used as biomarkers for node-positive patients at high risk of progression. The study also provides a rationale for selecting patients with node-positive PCa who might benefit the most from adjuvant immunotherapies. PATIENT SUMMARY: None of the available biomarkers can identify node-positive prostate cancer that will recur after surgery. We found that expression of PD-L1 by tumor cells and a high density of CD8+ T cells in tumor are associated with a higher risk of clinical progression in men with node-positive prostate cancer.

Linearized texture of three-dimensional extracellular matrix is mandatory for bladder cancer cell invasion

In the fields of biomaterials and tissue engineering simulating the native microenvironment is of utmost importance. As a major component of the microenvironment, the extracellular matrix (ECM) contributes to tissue homeostasis, whereas modifications of native features are associated with pathological conditions. Furthermore, three-dimensional (3D) geometry is an important feature of synthetic scaffolds favoring cell stemness, maintenance and differentiation. We analyzed the 3D structure, geometrical measurements and anisotropy of the ECM isolated from (i) human bladder mucosa (basal lamina and lamina propria) and muscularis propria; and, (ii) bladder carcinoma (BC). Next, binding and invasion of bladder metastatic cell line was observed on synthetic scaffold recapitulating anisotropy of tumoral ECM, but not on scaffold with disorganized texture typical of non-neoplastic lamina propria. This study provided information regarding the ultrastructure and geometry of healthy human bladder and BC ECMs. Likewise, using synthetic scaffolds we identified linearization of the texture as a mandatory feature for BC cell invasion. Integrating microstructure and geometry with biochemical and mechanical factors could support the development of an innovative synthetic bladder substitute or a tumoral scaffold predictive of chemotherapy outcomes.

MP70-15 LONG TERM OUTCOMES OF SALVAGE LYMPH NODE DISSECTION FOR CLINICALLY RECURRENT PROSTATE CANCER: RESULTS OF A SINGLE INSTITUTION SERIES WITH A MINIMUM FOLLOW-UP OF 5 YEARS

RESULTS: African Americans were less likely to have received prostate cancer screening in the pre-diagnosis year and less likely to have received any treatment. African Americans had higher outpatient visits compared to whites in the age group 66-75 (OR1⁄41.24, CI: 1.221.27); and age group 76-85 (OR1⁄41.18, CI: 1.14 -1.22). In the follow-up phases, African Americans had higher costs (range 28% to 49%). For age group 66-75, African Americans had higher hazard of all-cause mortality (HR1⁄41.22, CI1⁄41.09-1.38), and Asians had lower hazard of all-cause mortality (HR1⁄40.79, CI1⁄40.65-0.98). For age group 76-85, African Americans had higher hazard of all-cause mortality (HR1⁄41.22, CI1⁄41.05-1.41). CONCLUSIONS: The pattern of racial/ethnic disparity varies by age group. Higher mortality among African Americans may be associated with disparity in prostate cancer screening and treatment. Thus screening guidelines such as USPSTF, need to incorporate race/ ethnicity and age in developing recommendations.

Bladder cancer cell growth and motility implicate cannabinoid 2 receptor-mediated modifications of sphingolipids metabolism

The inhibitory effects demonstrated by activation of cannabinoid receptors (CB) on cancer proliferation and migration may also play critical roles in controlling bladder cancer (BC). CB expression on human normal and BC specimens was tested by immunohistochemistry. Human BC cells RT4 and RT112 were challenged with CB agonists and assessed for proliferation, apoptosis, and motility. Cellular sphingolipids (SL) constitution and metabolism were evaluated after metabolic labelling. CB1-2 were detected in BC specimens, but only CB2 was more expressed in the tumour. Both cell lines expressed similar CB2. Exposure to CB2 agonists inhibited BC growth, down-modulated Akt, induced caspase 3-activation and modified SL metabolism. Baseline SL analysis in cell lines showed differences linked to unique migratory behaviours and cytoskeletal re-arrangements. CB2 activation changed the SL composition of more aggressive RT112 cells by reducing (p < 0.01) Gb3 ganglioside (−50 ± 3%) and sphingosine 1-phosphate (S1P, −40 ± 4%), which ended up to reduction in cell motility (−46 ± 5%) with inhibition of p-SRC. CB2-selective antagonists, gene silencing and an inhibitor of SL biosynthesis partially prevented CB2 agonist-induced effects on cell viability and motility. CB2 activation led to ceramide-mediated BC cell apoptosis independently of SL constitutive composition, which instead was modulated by CB2 agonists to reduce cell motility.

Pure but Not Mixed Histologic Variants Are Associated With Poor Survival at Radical Cystectomy in Bladder Cancer Patients

Purpose To evaluate the impact of pure and mixed histologic variant versus pure urothelial carcinoma in nonmetastatic bladder cancer (BCa) patients treated with radical cystectomy (RC). Patients and Methods We evaluated data from 1067 patients treated with RC and pelvic lymph node dissection between 1990 and 2013 at a single institution tertiary‐care referral center. All specimens were evaluated by dedicated uropathologists. Univariable and multivariable Cox regression analyses tested the impact of the presence of pure and mixed histologic variants versus pure urothelial on recurrence, cancer‐specific mortality, and overall mortality after accounting for all available confounders. Results In total, 201 (19%) and 137 (13%) patients were found with mixed and pure variants at RC, respectively. Mixed preponderant variants were sarcomatoid, lymphoepitelial, squamous, and glandular; small‐cell and micropapillary variants were found mostly as pure variants. With a median follow‐up of 6.5 years, patients who harbored pure variant were found by multivariable analyses to have lower survival outcomes compared to pure urothelial carcinoma (all P < .01). Conversely, no differences were found between mixed variant versus pure urothelial by multivariable Cox regression analyses predicting recurrence, cancer‐specific mortality, and overall mortality (all P > .1). Conclusion The presence of histologic variants at RC is a common finding, accounting for approximately 30% of specimens. In this setting, the presence of a pure variant but not the presence of mixed variant with urothelial carcinoma is related to a detrimental effect on survival outcomes after RC. Micro‐Abstract The importance of a correct histologic variant classification in the decision making of bladder cancer patients have been recently highlighted by the new World Health Organization classification of the urothelial tract. Histologic variants at the time of radical cystectomy is a common finding, accounting for almost 30% of specimens, yet only pure histologic variants but not mixed histologic variants are associated with worse survival compared to pure urothelial cancer. Physicians should consider this parameter when counseling surgical patients.