Hélène Hovington

Genomic hallmarks of localized, non-indolent prostate cancer

Prostate tumours are highly variable in their response to therapies, but clinically available prognostic factors can explain only a fraction of this heterogeneity. Here we analysed 200 whole-genome sequences and 277 additional whole-exome sequences from localized, non-indolent prostate tumours with similar clinical risk profiles, and carried out RNA and methylation analyses in a subset. These tumours had a paucity of clinically actionable single nucleotide variants, unlike those seen in metastatic disease. Rather, a significant proportion of tumours harboured recurrent non-coding aberrations, large-scale genomic rearrangements, and alterations in which an inversion repressed transcription within its boundaries. Local hypermutation events were frequent, and correlated with specific genomic profiles. Numerous molecular aberrations were prognostic for disease recurrence, including several DNA methylation events, and a signature comprised of these aberrations outperformed well-described prognostic biomarkers. We suggest that intensified treatment of genomically aggressive localized prostate cancer may improve cure rates.

Bladder Tumor Infiltrating Mature Dendritic Cells and Macrophages as Predictors of Response to Bacillus Calmette-Guérin Immunotherapy

BACKGROUND The clinical significance of tumor-infiltrating dendritic cells (TIDCs) and tumor-associated macrophages (TAMs) as markers of immune response has been reported for many cancers. OBJECTIVE To measure tumor infiltration by CD83(+) dendritic cells (DCs) and CD68(+) macrophages in non-muscle-invasive urothelial cancer (NMIUC) prior to bacillus Calmette-Guérin (BCG) immunotherapy and to evaluate their significance in the response to immunotherapy. DESIGN, SETTING, AND PARTICIPANTS Patients with NMIUC at high risk of recurrence and progression were recruited for a study on markers of the response to BCG. INTERVENTION Patients were treated by transurethral resection followed by maintenance BCG. MEASUREMENTS Immunohistochemical staining with anti-CD83 and anti-CD68 monoclonal antibodies on 53 and 46 NMIUC tumors, respectively, prior to BCG treatment. A scoring index was calculated based on the average density of positive cells within the papillary axis, the stroma, lymphoid aggregates, and infiltration into tumors. RESULTS AND LIMITATIONS CD83(+) TIDCs were observed mostly within lymphoid aggregates. Multivariate Cox regression analysis showed that maintenance BCG (more than one maintenance cycle) was highly effective in patients with a low level of CD83(+) TIDCs at time of resection (hazard ratio [HR]: 0.035; p=0.002) but showed reduced efficacy in patients with a high level of CD83(+) TIDCs (HR: 0.87; p=0.810). A high level of infiltration by CD83(+) TIDCs slightly decreased the risk of recurrence in patients treated with one or no maintenance BCG cycle (HR: 0.4; p=0.117). In the same population, a strong infiltration of CD68(+) TAMs was associated with an increased risk of recurrence (HR: 3.8; p=0.013). CONCLUSIONS These results suggest that patients with a high level of infiltration by CD83(+) TIDCs or CD68(+) TAMs do not respond as well to BCG immunotherapy. If confirmed in larger cohorts, the pretreatment level of infiltration by these cells may be useful to influence the choice of treatment strategy.

High frequency of MAGE-A4 and MAGE-A9 expression in high-risk bladder cancer

Cancer‐testis (CT) genes encode proteins that are ideal targets for cancer immunotherapy because of their restricted expression in normal tissues and frequent expression in cancers. We previously observed that MAGE‐A9 was one of the CT genes most frequently expressed in bladder tumors. To confirm that observation and evaluate the potential prognostic value of MAGE‐A9 protein, we analyzed its expression by immunohistochemistry in 493 primary bladder tumors and 33 lymph node metastases, in comparison with MAGE‐A4 protein, also frequently expressed in bladder tumors. Overall, MAGE‐A4 and MAGE‐A9 were observed, respectively, in 38% and 63% of nonmuscle‐invasive tumors, 48% and 57% of muscle‐invasive tumors, 65% and 84% of carcinomas in situ and in 73% and 85% of lymph node metastases. Expression was associated with higher grade (MAGE‐A4, p = 0.007; MAGE‐A9, p = 0.012). In multivariate Cox regression analyses, expression of MAGE‐A9 in pTa tumors was associated with recurrence (HR = 1.829; p = 0.010). In univariate analyses, MAGE‐A4 expression in these same tumors was associated with progression to muscle‐invasive cancer (HR = 7.417, p = 0.013). MAGE‐A9 expression was even more predictive of progression as all tumors that progressed expressed this antigen. In muscle‐invasive bladder tumors, no association was found between expression of either MAGE and bladder cancer‐specific death. In conclusion, MAGE‐A9 is a target of choice for bladder cancer immunotherapy as it is expressed in 60% of bladder tumors, predominantly high‐grade tumors, and at higher frequency in pTis and metastatic tumors. Moreover, in pTa tumors, an immunotherapy targeting MAGE‐A9 could be protective against recurrence and progression to more advanced cancer.

Identification of PCA3 (DD3) in prostatic carcinoma by in situ hybridization

PCA3 is a specific marker of prostatic carcinoma. However, PCA3 has been detected only at RNA level and a corresponding PCA3 protein has never been identified. The aim of this study was to develop a technique capable of detecting PCA3 RNA on histology sections and to assess the cellular location of the molecule. Forty-eight formalin-fixed paraffin-embedded blocks of prostatectomy specimens were selected for PCA3 detection by in situ hybridization by both radioactive and chromogenic methods. Of the 48 sections, 28 contained prostatic adenocarcinoma and 20 had benign tissue located distant from the tumor. Using the radioactive detection method, 26 of 28 available cases (93%) of cancers presented at least focal cytoplasmic PCA3 expression. The benign glands located in proximity of the cancer presented PCA3 expression in eight (29%) cases, whereas those situated distant to the tumor showed focal expression in 2 of 20 (10%) cases only. High-grade prostatic intraepithelial neoplasia (HGPIN) expressed PCA3 in 25 of 26 (96%) cases. With the chromogenic detection method, 22 of the 24 interpretable cases (92%) of cancers had at least focal cytoplasmic staining. Benign glands located close to neoplastic glands expressed PCA3 in 8 (33%) cases, but none of those distant to the tumor expressed the marker. HGPIN was positive in 17 of 24 (71%) cases. The sensitivity, specificity, positive predictive value and negative predictive value for the detection of cancer were 93, 79, 71 and 95% for the radioactive detective method and 92, 80, 71 and 95% for the chromogenic detection method, respectively. Our study shows that PCA3 RNA is expressed by most prostate cancers and HGPIN. Normal glands rarely express the marker, except those located in immediate proximity of neoplastic glands, suggesting the presence of precursor molecular changes.

Tissue factor expression correlates with disease-specific survival in patients with node-negative muscle-invasive bladder cancer

Tissue factor (TF), a transmembrane glycoprotein responsible for initiating the extrinsic pathway of blood coagulation plays a key role in cancer growth, metastasis and angiogenesis. Various studies have demonstrated the prognostic potential of TF expression in several cancers. However, its role in bladder cancer is unclear. This study evaluated the prognostic potential of TF expression in muscle‐invasive bladder tumors from patients treated with radical cystectomies. Immunohistochemical staining using a monoclonal antibody (mAb) anti‐TF was carried out on sections of tissue microarray blocks containing cores of muscle‐invasive bladder tumors (4 cores/tumor) from 218 patients. The intensity of the staining was evaluated on a scale from 0 to 3 by two independent observers who were both unaware of the clinicopathological characteristics of the samples. TF was expressed in 77.6% of tumors, independently from baseline characteristics (age, gender, stage and grade) as assessed using the χ2 and Student t tests. During follow‐up (median: 2.6 years), 45.4% of the patients died from the progression of their cancer. Kaplan–Meier survival showed that among the 103 patients with node‐negative (N0) transitional cell carcinoma (TCC), those with TF‐positive tumors had shorter bladder cancer‐specific survival (p = 0.0276). Moreover, multivariate Cox regression analysis showed they had a 3.15‐fold greater risk of dying from bladder cancer (95% CI: 1.1–9.0; p = 0.032). In conclusion, TF expression was an independent predictor of disease‐specific survival in N0 muscle‐invasive TCCs treated by radical cystectomy and therefore, might help identify patients at higher risk of disease progression. These patients could potentially benefit from adjuvant chemotherapy.

Accelerated Induction of Bladder Cancer in Patched Heterozygous Mutant Mice

The PATCHED (PTC) gene is recognized as a tumor suppressor in basal cell carcinoma. Mapping of a minimal region of deletion at 9q22.3 and observation of a decreased PTC expression in superficial papillary bladder tumors led us to hypothesize that it could also be involved in this cancer. To further investigate this hypothesis, we submitted Ptc+/− heterozygous mutant mice and their wild-type littermates to chemical carcinogenesis by adding N-butyl-N-(4-hydroxybutyl) nitrosamine to their drinking water. Preneoplastic and neoplastic changes were observed significantly earlier in the Ptc+/− than in the wild-type mice. Our data support the hypothesis of Ptc acting as a tumor suppressor gene in bladder cancer.

The UGT2B28 Sex-steroid Inactivation Pathway Is a Regulator of Steroidogenesis and Modifies the Risk of Prostate Cancer Progression

BACKGROUND Androgen inactivation occurs mainly through the glucuronidation conjugative reaction mediated by UDP-glucuronosyltransferases (UGTs). This metabolic process is involved in the control of systemic and local androgen bioavailability. OBJECTIVE To examine the relationship among expression of the androgen-inactivating UGT2B28 enzyme, circulating steroid hormone levels, and clinical phenotype in prostate cancer (PCa). DESIGN, SETTING, AND PARTICIPANTS We conducted an analysis of a high-density prostate tumor tissue microarray consisting of 239 localized PCa cases. The study of 51 additional PCa patients with no copies of UDP glucuronosyltransferase 2B subfamily, polypeptide B28 (UGT2B28) in their genomes was performed to confirm the importance of the enzyme on circulating hormone levels. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Steroid hormones were measured by mass spectrometry. Multivariate Cox proportional hazard models assessed the influence of UGT2B28 on progression, and general linear model regression evaluated variations in hormone levels. RESULTS AND LIMITATIONS Tumor overexpression of UGT2B28 was associated with lower prostate-specific antigen levels at diagnosis, higher Gleason scores, margin and nodal invasion status, and it was shown to be an independent prognostic factor associated with progression. Enzyme overexpression correlated with 30% higher circulating levels of testosterone (T) and dihydrotestosterone (DHT). Patients with no copies of UGT2B28 in their genomes have lower levels of T (19%), DHT (17%), its glucuronide metabolites (18-38%), and enhanced levels of the adrenal precursor androstenedione (36%). CONCLUSIONS The UGT2B28 steroid-inactivating pathway modifies circulating T and DHT levels, and UGT2B28 overexpression is associated with high-grade PCa. Our work has uncovered the role of UGT2B28 as a regulator of steroidogenesis and underscores the interconnectivity among the steroid-inactivation capacity of cancer cells, hormone levels, disease characteristics, and the risk of cancer progression. PATIENT SUMMARY The androgen-inactivating UGT2B28 enzyme influences hormone levels, clinical and pathologic factors, and the risk of cancer progression.

High level of mature tumor-infiltrating dendritic cells predicts progression to muscle invasion in bladder cancer

A prognostic value for tumor-associated macrophages (TAMs) and tumor-infiltrating dendritic cells (TIDCs) has been reported in many human cancers. The objective of this study is to determine the prognostic value of CD83(+) mature TIDCs and CD68(+) TAMs in non-muscle-invasive bladder cancer at first diagnosis. Immunohistochemistry staining was performed with anti-CD68 and anti-CD83 monoclonal antibodies on tissue sections from 93 formalin-fixed, paraffin-embedded tissue blocks from pTa and pT1 bladder tumors. A scoring index based on the average density of observed positive cells in the papillary axis, the stroma, lymphoid aggregates, and into tumor foci was calculated for each patient. Comparison of baseline characteristics with marker levels was done using Pearson χ(2) or Fisher exact test. Kaplan-Meier analyses and Cox regression models were fitted to evaluate the prognostic value of TIDCs and TAMs. The absence of both CD68(+) TAMs and CD83(+) TIDCs was associated with tumor recurrence. The presence of TIDCs was associated with a significant risk of progression to muscle-invasive cancer (hazard ratio, 8.253; P = .0179). Patients were risk stratified using age and TIDC score. Patients 70 years or older with a high score of TIDCs had a 56% progression-free survival after 6 years compared with 94% for patients younger than 70 years with a low score of TIDCs. None of 20 patients with a low score of TAMs progressed. These data indicate that the presence of mature TIDCs and possibly TAMs may help risk-stratify patients at the time of first diagnosis of non-muscle-invasive bladder cancer and may be useful in tailoring follow-up and treatment strategies.

Translating a Prognostic DNA Genomic Classifier into the Clinic: Retrospective Validation in 563 Localized Prostate Tumors

BACKGROUND Localized prostate cancer is clinically heterogeneous, despite clinical risk groups that represent relative prostate cancer-specific mortality. We previously developed a 100-locus DNA classifier capable of substratifying patients at risk of biochemical relapse within clinical risk groups. OBJECTIVE The 100-locus genomic classifier was refined to 31 functional loci and tested with standard clinical variables for the ability to predict biochemical recurrence (BCR) and metastasis. DESIGN, SETTING, AND PARTICIPANTS Four retrospective cohorts of radical prostatectomy specimens from patients with localized disease were pooled, and an additional 102-patient cohort used to measure the 31-locus genomic classifier with the NanoString platform. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The genomic classifier scores were tested for their ability to predict BCR (n=563) and metastasis (n=154), and compared with clinical risk stratification schemes. RESULTS AND LIMITATIONS The 31-locus genomic classifier performs similarly to the 100-locus classifier. It identifies patients with elevated BCR rates (hazard ratio=2.73, p<0.001) and patients that eventually develop metastasis (hazard ratio=7.79, p<0.001). Combining the genomic classifier with standard clinical variables outperforms clinical models. Finally, the 31-locus genomic classifier was implemented using a NanoString assay. The study is limited to retrospective cohorts. CONCLUSIONS The 100-locus and 31-locus genomic classifiers reliably identify a cohort of men with localized disease who have an elevated risk of failure. The NanoString assay will be useful for selecting patients for treatment deescalation or escalation in prospective clinical trials based on clinico-genomic scores from pretreatment biopsies. PATIENT SUMMARY It is challenging to determine whether tumors confined to the prostate are aggressive, leading to significant undertreatment and overtreatment. We validated a test based on prostate tumor DNA that improves estimations of relapse risk, and that can help guide treatment planning.

Comparison of digital image analysis and visual scoring of KI-67 in prostate cancer prognosis after prostatectomy.

BackgroundThe tumor proliferative index marker Ki-67 was shown to be associated with clinically significant outcomes in prostate cancer, but its clinical application has limitations due to lack of uniformity and consistency in quantification. Our objective was to compare the measurements obtained with digital image analysis (DIA) versus virtual microscopy (visual scoring (VS)).MethodsTo do so, we compared the measurement distributions of each technique and their ability to predict clinically useful endpoints. A tissue microarray series from a cohort of 225 men who underwent radical prostatectomy was immunostained for Ki-67. The percentage of Ki-67 positive nuclei in malignant cells was assessed both by VS and DIA, and a H–score was calculated. The distribution and predictive ability of these scoring methods to predict biochemical recurrence (BCR) and death from prostate cancer (DPCa) were compared using Mann–Whitney test and C-index.ResultsThe measurements obtained with VS were similar to the DIA measurements (p = 0.73) but dissimilar to the H-score (p < 0.001). Cox regression models showed that Ki-67 was associated with BCR (HR 1.46, 95 % CI 1.10-1.94) and DPCa (HR 1.26, 95 % CI 1.06-1.50). C-indexes revealed that Ki-67 was a better predictor of DPCa (0.803, 0.8059 and 0.789; VS, DIA and H-score, respectively) than of BCR (0.625, 0.632 and 0.604; VS, DIA and H-score, respectively).ConclusionThe measurement distributions and the predictive abilities of VS and DIA were similar and presented the same predictive behaviour in our cohort, supporting the role of Ki-67 proliferative index as an important prognostic factor of BCR and DPCa in prostate cancer post RP.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/6656878501536663