Results of a Randomized Phase II Trial of Intense Androgen Deprivation Therapy prior to Radical Prostatectomy in Men with High-Risk Localized Prostate Cancer

PURPOSE

This multicenter randomized phase 2 trial investigates the impact of intense androgen deprivation on radical prostatectomy pathologic response and radiographic and tissue biomarkers in localized prostate cancer (NCT02903368).

MATERIALS AND METHODS

Eligible patients had a Gleason score ≥4+3=7, prostate specific antigen >20 ng/mL or T3 disease and lymph nodes <20 mm. In Part 1, patients were randomized 1:1 to apalutamide, abiraterone acetate, prednisone and leuprolide (AAPL) or abiraterone, prednisone, leuprolide (APL) for 6 cycles (1 cycle=28 days) followed by radical prostatectomy. Surgical specimens underwent central review. The primary end point was the rate of pathologic complete response or minimum residual disease (minimum residual disease, tumor ≤5 mm). Secondary end points included prostate specific antigen response, positive margin rate and safety. Magnetic resonance imaging and tissue biomarkers of pathologic outcomes were explored.

RESULTS

The study enrolled 118 patients at 4 sites. Median age was 61 years and 94% of patients had high-risk disease. The combined pathologic complete response or minimum residual disease rate was 22% in the AAPL arm and 20% in the APL arm (difference: 1.5%; 1-sided 95% CI -11%, 14%; 1-sided p=0.4). No new safety signals were observed. There was low concordance and correlation between posttherapy magnetic resonance imaging assessed and pathologically assessed tumor volume. PTEN-loss, ERG positivity and presence of intraductal carcinoma were associated with extensive residual tumor.

CONCLUSIONS

Intense neoadjuvant hormone therapy in high-risk prostate cancer resulted in favorable pathologic responses (tumor <5 mm) in 21% of patients. Pathologic responses were similar between treatment arms. Part 2 of this study will investigate the impact of adjuvant hormone therapy on biochemical recurrence.

Metabolomics of Prostate Cancer Gleason Score in Tumor Tissue and Serum

Gleason score, a measure of prostate tumor differentiation, is the strongest predictor of lethal prostate cancer at the time of diagnosis. Metabolomic profiling of tumor and of patient serum could identify biomarkers of aggressive disease and lead to the development of a less-invasive assay to perform active surveillance monitoring. Metabolomic profiling of prostate tissue and serum samples was performed. Metabolite levels and metabolite sets were compared across Gleason scores. Machine learning algorithms were trained and tuned to predict transformation or differentiation status from metabolite data. A total of 135 metabolites were significantly different (P _adjusted < 0.05) in tumor versus normal tissue, and pathway analysis identified one sugar metabolism pathway (P _adjusted = 0.03). Machine learning identified profiles that predicted tumor versus normal tissue (AUC of 0.82 ± 0.08). In tumor tissue, 25 metabolites were associated with Gleason score (unadjusted P < 0.05), 4 increased in high grade while the remainder were enriched in low grade. While pyroglutamine and 1,5-anhydroglucitol were correlated (0.73 and 0.72, respectively) between tissue and serum from the same patient, no metabolites were consistently associated with Gleason score in serum. Previously reported as well as novel metabolites with differing abundance were identified across tumor tissue. However, a "metabolite signature" for Gleason score was not obtained. This may be due to study design and analytic challenges that future studies should consider. IMPLICATIONS: Metabolic profiling can distinguish benign and neoplastic tissues. A novel unsupervised machine learning method can be utilized to achieve this distinction.

Results of a phase II trial of intense androgen deprivation therapy prior to radical prostatectomy (RP) in men with high-risk localized prostate cancer (PC)

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Background: Patients with high-risk localized PC have an increased risk of recurrence and death despite treatment. Abiraterone acetate (AA), a potent CYP17 inhibitor, and apalutamide, a next generation anti-androgen, have each demonstrated improved overall survival in metastatic PC. In this multicenter randomized phase II trial we investigate the impact of intense androgen deprivation on RP pathologic response (NCT02903368). Methods: Eligible patients had a Gleason score ≥4+3=7, PSA >20 ng/mL or T3 disease (by prostate MRI) and lymph node <20 mm. During Part 1 of the study, patients were randomized 1:1 to AA + prednisone + apalutamide + leuprolide (APAL) or AA + prednisone + leuprolide (APL) for 6 cycles (1 cycle=28 days) followed by RP. All RPs underwent central pathology review. The primary endpoint was the rate of a pathologic complete response (pCR) or minimum residual disease (MRD, tumor ≤5 mm). Secondary endpoints include PSA response, surgical staging at RP, positive margin rate, and safety. Results: 118 patients were enrolled at four sites. Median age was 61 (range 46-72) years. The majority of patients had NCCN high-risk disease [n=111, 94%; T3 n=73 (62%), Gleason 8-10 n=84 (71%), PSA >20 ng/mL n=28 (24%)]. 114 (97%) patients completed 6 therapy cycles followed by RP. Median PSA nadir was <0.01 versus 0.02 ng/mL and time to nadir was 4.2 versus 4.6 months in the APAL and APL arms, respectively. RP outcomes are displayed in Table. The combined pCR or MRD rate was 21.8% in the APAL arm and 20.3% in the APL arm (p=0.85). 13 (11%) patients (8 in APAL; 5 in APL) experienced grade 3 treatment-related adverse events (TrAEs). The most common grade 3 TrAEs were hypertension (5%), elevated ALT (3%) and elevated AST (3%). No grade 4 or 5 TrAE was reported. Conclusions: Intense neoadjuvant hormone therapy followed by RP in men with high-risk PC resulted in favorable pathologic responses (<5 mm residual tumor) in 21% of patients. Pathologic responses were similar between the treatment arms. Follow-up is necessary to evaluate the significance of a pathologic response on recurrence rates. Part 2 of this trial will investigate the impact of an additional 12 months of APAL post-RP on biochemical recurrence. A phase 3 trial investigating neoadjuvant apalutamide + leuprolide prior to RP is ongoing. Clinical trial information: NCT02903368 . [Table: see text]

Multiple primary prostate tumors with differential drug sensitivity

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Background: The differential aggressiveness of potentially independent prostate cancer clones remains largely unknown. Appropriate prostate cancer staging using mpMRI and biopsy tissue can be confounded by sampling error. To date, there has been no understanding of whether clonal variability influences management decisions for localized prostate tumors. We sought to identify the sensitivity and genomic profile of distinct localized tumors from a patient following systemic intense neoadjuvant androgen deprivation therapy (ADT). Methods: A 66-year-old man with high risk prostate cancer enrolled in a Phase 2 study of intense neoadjuvant ADT (goserelin + enzalutamide; inADT). Baseline mpMRI showed a single semi-contiguous lesion encompassing the right apical-mid PZ extending into the left distal apical PZ. MR/US-fusion targeted biopsy was performed before 6 months of inADT. A second mpMRI was performed before radical prostatectomy. Whole exome sequencing on microdissected tumor foci identified somatic mutations and copy number alterations, which were further used with immunohistochemistry to assess tumor clonal architecture and genomic/phenotypic evolution of treatment resistant tumor. Results: We found two clonally independent tumors exhibited intrinsic heterogeneity at baseline which correlated with response or resistance. Biopsies of distinct left- and right-sided tumors showed differing histologies. mpMRI and pathology showed near complete response of the left-sided tumor and substantial resistance of the right-sided tumor, which exhibited a large intraductal component. Histology and whole exome data highlighted a divergence in the status of PTEN and TP53, tumor suppressor genes implicated in prostate cancer progression. Conclusions: These data highlight that even nascent prostate cancer is heterogenous and neoadjuvant therapeutic strategies will need to consider this for clinical optimization. Evolutionary trajectories that resulted in tumor heterogeneity in this case likely contributed to our observation that two independent prostate tumor nodules with distinct genetic alterations responded differently to neoadjuvant intense ADT. Clinical trial information: NCT02430480.

Metacure: Multi-arm multimodality therapy for very high risk localized and low volume metastatic prostatic adenocarcinoma

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Background: Therapeutic advances in the management of metastatic castration-resistant prostate cancer (mCRPC) have not been matched in non-castrate states. A key obstacle is the traditional paradigm in which therapies with significant benefit in mCRPC are then studied in patients (pts) with localized, rising PSA or early metastatic disease using time-to-event (TTE) outcomes (e.g. biochemical recurrence, radiographic progression or death). These trials are costly, lengthy and often give inconclusive results that do not change practice nor provide a methodology to rank regimens based on efficacy. A new strategy is needed that gives a rapid efficacy readout and prioritizes approaches for large-scale testing. Methods: Metacure is a multi-arm, multi-stage randomized Phase 2 trial in which novel systemic therapies are studied in the context of a multimodality approach, which includes radical prostatectomy + pelvic and retroperitoneal lymph node dissection, if applicable, stereotactic radiotherapy (RT) to osseous metastases, and an option for adjuvant RT based on risk factors. The arms include combinations of ADT + apalutamide +/- abiraterone acetate and prednisone. Non-castrate prostate cancer pts with high probability of relapse or death from disease ranging from very high risk localized to low-volume metastatic disease are eligible. The primary endpoint is pathologic complete response and minimal residual disease. The secondary endpoint is undetectable PSA with non-castrate levels of testosterone. Both are binary endpoints that circumvent interpretations of the clinical relevance of TTE outcomes, providing a read-out of success or failure in a shorter time frame with fewer pts. The uniform entry criteria and continuous randomization enables ranking and prioritization of the strategies evaluated for further development in large-scale trials so that only the most effective ones move forward. This multicenter trial is managed by the Prostate Cancer Clinical Trials Consortium, funded by Janssen and is currently open and actively accruing. Future plans include opening a cohort of pts with aggressive non-castrate disease harboring DNA damage repair alterations. Clinical trial information: NCT03436654.

Evaluation of Intense Androgen Deprivation Before Prostatectomy: A Randomized Phase II Trial of Enzalutamide and Leuprolide With or Without Abiraterone

PURPOSE

Patients with locally advanced prostate cancer have an increased risk of cancer recurrence and mortality. In this phase II trial, we evaluate neoadjuvant enzalutamide and leuprolide (EL) with or without abiraterone and prednisone (ELAP) before radical prostatectomy (RP) in men with locally advanced prostate cancer.

PATIENTS AND METHODS

Eligible patients had a biopsy Gleason score of 4 + 3 = 7 or greater, prostate-specific antigen (PSA) greater than 20 ng/mL, or T3 disease (by prostate magnetic resonance imaging). Lymph nodes were required to be smaller than 20 mm. Patients were randomly assigned 2:1 to ELAP or EL for 24 weeks followed by RP. All specimens underwent central pathology review. The primary end point was pathologic complete response or minimal residual disease (residual tumor ≤ 5 mm). Secondary end points were PSA, surgical staging, positive margins, and safety. Biomarkers associated with pathologic outcomes were explored.

RESULTS

Seventy-five patients were enrolled at four centers. Most patients had high-risk disease by National Comprehensive Cancer Network criteria (n = 65; 87%). The pathologic complete response or minimal residual disease rate was 30% (n = 15 of 50) in ELAP-treated patients and 16% (n = four of 25) in EL-treated patients (two-sided P = .263). Rates of ypT3 disease, positive margins, and positive lymph nodes were similar between arms. Treatment was well-tolerated. Residual tumors in the two arms showed comparable levels of ERG, PTEN, androgen receptor PSA, and glucocorticoid receptor expression. Tumor ERG positivity and PTEN loss were associated with more extensive residual tumors at RP.

CONCLUSION

Neoadjuvant hormone therapy followed by RP in locally advanced prostate cancer resulted in favorable pathologic responses in some patients, with a trend toward improved pathologic outcomes with ELAP. Longer follow-up is necessary to evaluate the impact of therapy on recurrence rates. The potential association of ERG and PTEN alterations with worse outcomes warrants additional investigation.

Abstract 4350: Integrative and multiregional molecular analysis of localized, high grade prostate cancer treated with neoadjuvant androgen deprivation treatment

Neoadjuvant intense androgen deprivation treatment (ADT) in localized, high risk prostate cancer (HG PCa) has varied degrees of response. While some patients have an outstanding response with minimal residual disease [MRD; ≤0.5mm of tumor at radical prostatectomy (RP)], others have no response but delay potential curative treatment. Previous studies have demonstrated that HG PCa is heterogenous, however previous studies have not investigated whether heterogeneity itself or specific genetic molecular features correlate with response to intense neoadjuvant ADT. Herein, we provide an integrated molecular analysis of the spatial heterogeneity of HG PCa treated with neoadjuvant ADT. We examined 53 pre-treatment biopsy samples (n=35 biopsies containing tumor, n=18 normal prostate tissue) from 14 patients with matched blood normals who were treated with an intense neoadjuvant regimen of lupron plus abiraterone/enzalutamide. Patients were stratified as exceptional responders (n=8; MRD at RP) or non-responders (n=6; pT3 or lymph node positive at RP). We performed whole exome and whole transcriptome sequencing on multiple, spatially heterogeneous biopsies within each patient to examine the role of heterogeneity in response to therapy. We called somatic and germline variants, inferred mutational clonality, phylogenetic relationships, called genetic fusion, and analyzed differentially expressed genes. After QC, we observed well known prostate driver mutations (SPOP, ATM, TP53, FOXA1, PTEN, and APC) across the entire cohort (n=14 patients). Within each individual, all driver mutations were clonal across tumor cores, but the proportion of all mutations that were always clonal varied widely (0.08-0.57), median 0.3). Among known drivers, SPOP mutations were only observed in exceptional responders (4/8 v. 0/6), and TP53 and PTEN mutations were only observed in non-responders (4/6 v. 0/8). Responders and non-responders did not differ by mutational or copy number burden. Mutational heterogeneity varied greatly between samples, however this did not split between responders and non-responders. In terms of gene expression, exceptional responders showed upregulation of androgen and estrogen response pathways, while non-responders had increased expression of E2F targets and cell cycle pathways. We confirmed that a subset of localized, HG PCa are molecularly heterogeneous in terms of mutations and expression. We are presently underpowered to explain the genomic differences between excpetional responders and non-responders. However, molecular heterogeneous and homogenous HG PCa tumors can respond to intense neoadjuvant ADT therapy. We are currently analyzing a larger cohort.

Citation Format: Stephanie A. Wankowicz, Michaela Bowden, Rosina Lis, Claire Margolis, Dimitri Livitz, Ignaty Leshchiner, David Liu, Meng Xiao He, Zhenwei Zhang, Gad Getz, Mary-Ellen Taplin, Eliezer Van Allen. Integrative and multiregional molecular analysis of localized, high grade prostate cancer treated with neoadjuvant androgen deprivation treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4350.

Results of a phase II trial of neoadjuvant abiraterone + prednisone+ enzalutamide + leuprolide (APEL) versus enzalutamide + leuprolide (EL) for patients with high-risk localized prostate cancer (PC) undergoing radical prostatectomy (RP)

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Background: Patients with high-risk PC have an increased risk of recurrence and mortality despite therapy. Abiraterone, a CYP17 inhibitor, and enzalutamide, a next generation anti-androgen, have demonstrated improved overall survival in metastatic PC. In this multicenter randomized phase II trial, we evaluate the impact of second generation hormone therapy on RP pathologic outcomes. Methods: Eligible patients had biopsy Gleason score ≥4+3=7, PSA >20 ng/mL or cT3 disease (by prostate MRI). Lymph node were require to be <20 mm. Patients were randomized 2:1 to APE:EL for 6 cycles (24 weeks) followed by RP. All RPs underwent central pathology review. The primary endpoint was the rate of pathologic complete response (pCR) or minimum residual disease (MRD, tumor ≤5 mm). Secondary endpoints include PSA response, surgical staging at RP, positive margin rate, and safety. Results: 75 patients were enrolled at four sites: DFCI/BWH (n=55), BIDMC (n=11), UW (n=5), JHU (n=4). Median age was 62 years. Most patients had NCCN high-risk disease [n=66, 88%; cT3 n=21 (28%), Gleason 8-10 n=59 (79%), PSA >20 ng/mL n=17 (23%)]. All patients completed 6 cycles followed by RP. Median PSA nadir was 0.03 and 0.02 ng/mL and time to nadir was 3.7 and 4.6 months in the APEL and EL arms, respectively. The combined pCR or MRD rate was 30% (n=15/50) in the APEL arm and 16% (n=4/25) in the EL arm. The response difference was 14% (80% CI -3%-30%, p=0.263). 15 patients (14 in APEL; 1 in EL) had grade 3 adverse events (AEs). The most common grade 3 AEs were hypertension (n=7) and ALT increase (n=5). No grade 4-5 AEs occurred. Conclusions: Neoadjuvant hormone therapy plus RP in men with high-risk PC resulted in favorable pathologic responses (≤5 mm residual tumor) in 16-30% with a trend towards improved pathologic outcomes with APEL and acceptable safety profile. Follow-up is necessary to evaluate the impact of therapy on recurrence rates. Clinical trial information: NCT02268175. [Table: see text]

Expression of PD-L1 in Hormone-naïve and Treated Prostate Cancer Patients Receiving Neoadjuvant Abiraterone Acetate plus Prednisone and Leuprolide

Purpose: Programmed cell death ligand-1 (PD-L1)/programmed cell death-1 (PD-1) blockade has been unsuccessful in prostate cancer, with poor immunogenicity and subsequent low PD-L1 expression in prostate cancer being proposed as an explanation. However, recent studies indicate that a subset of prostate cancer may express significant levels of PD-L1. Furthermore, the androgen antagonist enzalutamide has been shown to upregulate PD-L1 expression in prostate cancer preclinical models. In this study, we evaluated the effect of neoadjuvant androgen deprivation therapy with abiraterone acetate plus prednisone and leuprolide (Neo-AAPL) on PD-L1 expression in prostate cancer.Experimental Design: Radical prostatectomy (RP) tissues were collected from 44 patients with intermediate- to high-risk prostate cancer who underwent RP after Neo-AAPL treatment. Untreated prostate cancer tissues were collected from 130 patients, including 44 matched controls for the Neo-AAPL cases. Tumor PD-L1 expression was detected by IHC using validated anti-PD-L1 antibodies. Tumor-infiltrating CD8⁺ cells were analyzed in trial cases and matched controls. Expression of DNA mismatch repair genes was examined in PD-L1-positive tumors.Results: Neo-AAPL-treated tumors showed a trend toward decreased PD-L1 positivity compared with matched controls (7% vs. 21% having ≥1% positive tumor cells; P = 0.062). Treated tumors also harbored significantly fewer tumor-infiltrating CD8⁺ cells (P = 0.029). In 130 untreated prostate cancers, African American ethnicity, elevated serum PSA, and small prostate independently predicted tumor PD-L1 positivity. Loss of MSH2 expression was observed in 1 of 21 PD-L1-positive tumors.Conclusions: A subset of prostate cancer expresses PD-L1, which is not increased by Neo-AAPL treatment, indicating that combining Neo-AAPL treatment with PD-L1/PD-1 blockade may not be synergistic. Clin Cancer Res; 23(22); 6812-22. ©2017 AACR.

Stromal and epithelial transcriptional map of initiation progression and metastatic potential of human prostate cancer

While progression from normal prostatic epithelium to invasive cancer is driven by molecular alterations, tumor cells and cells in the cancer microenvironment are co-dependent and co-evolve. Few human studies to date have focused on stroma. Here, we performed gene expression profiling of laser capture microdissected normal non-neoplastic prostate epithelial tissue and compared it to non-transformed and neoplastic low-grade and high-grade prostate epithelial tissue from radical prostatectomies, each with its immediately surrounding stroma. Whereas benign epithelium in prostates with and without tumor were similar in gene expression space, stroma away from tumor was significantly different from that in prostates without cancer. A stromal gene signature reflecting bone remodeling and immune-related pathways was upregulated in high compared to low-Gleason grade cases. In validation data, the signature discriminated cases that developed metastasis from those that did not. These data suggest that the microenvironment may influence prostate cancer initiation, maintenance, and metastatic progression.Stromal cells contribute to tumor development but the mechanisms regulating this process are still unclear. Here the authors analyze gene expression profiles in the prostate and show that stromal gene signature changes ahead of the epithelial gene signature as prostate cancer initiates and progresses.

Genomic mechanisms of resistance to neoadjuvant leuprolide plus abiraterone in locally advanced prostate cancer

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Background: Blocking both gonadal and extragonadal androgens with leuprolide and abiraterone acetate (AA) is approved by the FDA to treat mCRPC. Applying this treatment in the neoadjuvant setting reduced intratumoral testosterone levels in our Phase 2 trial, but pathologic CR's were rare and minimal residual disease was observed in some patients. Methods: We performed laser capture microdissection to isolate pure foci of residual tumor cells from 19 patients who underwent RP following 24 weeks of leuprolide plus AA. We also isolated 19 foci of matched benign glands as germline controls. In 15 of the 19 cases, we dissected 2 spatially-distinct foci of residual tumor. We then performed whole exome sequencing to assess somatic mutations and copy number variations (CNVs). Results: A diversity of genomic resistance mechanisms were observed. Resistance to AA as predicted by mutation of the ligand binding domain of AR was observed in only one case. In contrast, the majority residual tumor foci harbored CNVs coinciding with gain of oncogenes or loss of tumor suppressor genes. Importantly, only a limited number of alterations were shared between foci from the same case, as most mutations were unshared. Shared CNVs frequently included arm-level single copy losses of 10q ( PTEN), 13q ( BRCA2), 5q ( CHD1), 17p ( TP53), 16q ( ZFHX3) and 8p ( NKX3-1), and gain of 8q ( MYC). Mutations not shared by foci in the same case included further biallelic inactivation of PTEN, BRCA2 and TP53, as well as point mutations and single copy losses of BRCA1 and RB1. Distinct, focal gains included AR, PIK3CA and BRAF, and mutations also accumulated in KMT2B, KMT2C and KMT2D. Conclusions: By sampling multiple foci of residual tumor, we identified mutations that likely emerged by subclonal selection by ADT, which cooperated with the shared, clonal mutations that contributed to de novo development of the index lesion. Strikingly, the spectrum of alterations mimics mCRPC with enrichment for alterations affecting cell cycle, DNA damage repair and chromatin modifier pathways. If these alterations permit the tumor to evade AR directed therapy and subsequently mediate relapse, adjuvant therapies targeted to these mutations may increase survival. Clinical trial information: NCT00924469.

Pathology-Driven Comprehensive Proteomic Profiling of the Prostate Cancer Tumor Microenvironment

Prostate cancer is the second most common cancer in men worldwide. Gleason grading is an important predictor of prostate cancer outcomes and is influential in determining patient treatment options. Clinical decisions based on a Gleason score of 7 are difficult as the prognosis for individuals diagnosed with Gleason 4+3 cancer is much worse than for those diagnosed with Gleason 3+4 cancer. Laser capture microdissection (LCM) is a highly precise method to isolate specific cell populations or discrete microregions from tissues. This report undertook a detailed molecular characterization of the tumor microenvironment in prostate cancer to define the proteome in the epithelial and stromal regions from tumor foci of Gleason grades 3 and 4. Tissue regions of interest were isolated from several Gleason 3+3 and Gleason 4+4 tumors using telepathology to leverage specialized pathology expertise to support LCM. Over 2,000 proteins were identified following liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis of all regions of interest. Statistical analysis revealed significant differences in protein expression (>100 proteins) between Gleason 3 and Gleason 4 regions-in both stromal and epithelial compartments. A subset of these proteins has had prior strong association with prostate cancer, thereby providing evidence for the authenticity of the approach. Finally, validation of these proteins by immunohistochemistry has been obtained using an independent cohort of prostate cancer tumor specimens.Implications: This unbiased strategy provides a strong foundation for the development of biomarker protein panels with significant diagnostic and prognostic potential. Mol Cancer Res; 15(3); 281-93. ©2017 AACR.

A Phase II Trial of Abiraterone Combined with Dutasteride for Men with Metastatic Castration-Resistant Prostate Cancer

Purpose: Despite the efficacy of abiraterone, a CYP17A1 inhibitor, in metastatic castration-resistant prostate cancer (CRPC), nearly all patients develop resistance. The purpose of this phase II study was to evaluate mechanisms of resistance to more complete androgen synthesis inhibition with abiraterone and dutasteride.Experimental Design: Eligible patients with metastatic CRPC underwent a baseline metastasis biopsy. Patients received abiraterone and prednisone for two 4-week cycles. After this time, high-dose dutasteride (3.5 mg daily) was added. Patients continued therapy until study withdrawal or radiographic progression. Repeat metastasis biopsy was obtained at progression. The primary endpoint was to assess mechanisms of resistance. Serum hormone and abiraterone levels were assessed. Tissue was assessed for androgen receptor (AR) and AR splice variant-7 (ARV7) expression.Results: Forty patients were enrolled. Sixty percent (n = 24) achieved a ≥50% reduction in prostate-specific antigen (PSA). The median time to radiographic progression was 11 months. Nearly all baseline (n = 29 of 31) and posttreatment (n = 16 of 16) tumors tested for AR nuclear expression were positive. Of those tested, ARV7 expression was present in 48% (n = 10 of 21) of baseline and 42% (n = 5 of 12) of treatment discontinuation specimens. Compared with patients with higher serum abiraterone levels at treatment discontinuation, patients with lower levels had higher circulating androgens.Conclusions: Despite increased androgen synthesis inhibition, we demonstrate that tumor AR axis remains important in disease progression. We highlight that abiraterone metabolism and pharmacokinetics may play a role in resistance. The noncomparative design limits conclusions on the efficacy of dual therapy with abiraterone and dutasteride, but the results support development of further multifaceted approaches toward AR inhibition. Clin Cancer Res; 23(4); 935-45. ©2016 AACR.

Prognostic Utility of a New mRNA Expression Signature of Gleason Score

PURPOSE

Gleason score strongly predicts prostate cancer mortality; however, scoring varies among pathologists, and many men are diagnosed with intermediate-risk Gleason score 7. We previously developed a 157-gene signature for Gleason score using a limited gene panel. Using a new whole-transcriptome expression dataset, we verified the previous signature's performance and developed a new Gleason signature to improve lethal outcome prediction among men with Gleason score 7.

EXPERIMENTAL DESIGN

We generated mRNA expression data from prostate tumor tissue from men in the Physicians' Health Study and Health Professionals Follow-Up Study (N = 404) using the Affymetrix Human Gene 1.0 ST microarray. The Prediction Analysis for Microarrays method was used to develop a signature to distinguish high (≥8) versus low (≤6) Gleason score. We evaluated the signature's ability to improve prediction of lethality among men with Gleason score 7, adjusting for 3 + 4/4 + 3 status, by quantifying the area under the receiver operating characteristic (ROC) curve (AUC).

RESULTS

We identified a 30-gene signature that best distinguished Gleason score ≤6 from ≥8. The AUC to predict lethal disease among Gleason score 7 men was 0.76 [95% confidence interval (CI), 0.67-0.84] compared with 0.68 (95% CI, 0.59-0.76) using 3 + 4/4 + 3 status alone (P = 0.0001). This signature was a nonsignificant (P = 0.09) improvement over our previous signature (AUC = 0.72).

CONCLUSIONS

Our new 30-gene signature improved prediction of lethality among men with Gleason score 7. This signature can potentially become a useful prognostic tool for physicians to improve treatment decision making. Clin Cancer Res; 23(1); 81-87. ©2016 AACRSee related commentary by Yin et al., p. 6.

Calcium-Sensing Receptor Tumor Expression and Lethal Prostate Cancer Progression

CONTEXT

Prostate cancer metastases preferentially target bone, and the calcium-sensing receptor (CaSR) may play a role in promoting this metastatic progression.

OBJECTIVE

We evaluated the association of prostate tumor CaSR expression with lethal prostate cancer.

DESIGN

A validated CaSR immunohistochemistry assay was performed on tumor tissue microarrays. Vitamin D receptor (VDR) expression and phosphatase and tensin homolog tumor status were previously assessed in a subset of cases by immunohistochemistry. Cox proportional hazards models adjusting for age and body mass index at diagnosis, Gleason grade, and pathological tumor node metastasis stage were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of CaSR expression with lethal prostate cancer.

SETTING

The investigation was conducted in the Health Professionals Follow-up Study and Physicians' Health Study.

PARTICIPANTS

We studied 1241 incident prostate cancer cases diagnosed between 1983 and 2009.

MAIN OUTCOME

Participants were followed up or cancer-specific mortality or development of metastatic disease.

RESULTS

On average, men were followed up 13.6 years, during which there were 83 lethal events. High CaSR expression was associated with lethal prostate cancer independent of clinical and pathological variables (HR 2.0; 95% CI 1.2-3.3). Additionally, there was evidence of effect modification by VDR expression; CaSR was associated with lethal progression among men with low tumor VDR expression (HR 3.2; 95% CI 1.4-7.3) but not in cases with high tumor VDR expression (HR 0.8; 95% CI 0.2-3.0).

CONCLUSIONS

Tumor CaSR expression is associated with an increased risk of lethal prostate cancer, particularly in tumors with low VDR expression. These results support further investigating the mechanism linking CaSR with metastases.

Profiling the tumor microenvironment proteome in prostate cancer using laser capture microdissection coupled to LC⿿MS⿿A technical report

Laser capture microdissection (LCM) allows microscopic procurement of specific cell types from tissue sections. Here, we present an optimized workflow for coupling LCM to LC⿿MS/MS including: sectioning of tissue, a standard LCM workflow, protein digestion and advanced LC⿿MS/MS. Soluble proteins extracted from benign epithelial cells, their associated stroma, tumor epithelial cells and their associated stromal cells from a single patient tissue sample were digested and profiled using advanced LC⿿MS/MS. The correlation between technical replicates was R² = 0.99 with a mean % CV of 9.55% ± 8.73. The correlation between sample replicates was R² = 0.97 with a mean % CV of 13.83% ± 10.17. This represents a robust, systematic approach for profiling of the tumor microenvironment using LCM coupled to label-free LC⿿MS/MS.

The androgen receptor cistrome is extensively reprogrammed in human prostate tumorigenesis

Master transcription factors interact with DNA to establish cell-type identity and to regulate gene expression in mammalian cells^1,2. The genome-wide map of these transcription factor binding sites has been termed the cistrome³. Here we show that the androgen receptor (AR) cistrome undergoes extensive reprogramming during prostate epithelial transformation in man. Using human prostate tissue, we observed a core set of AR binding sites that are consistently reprogrammed in tumors. FOXA1 and HOXB13, co-localized with the reprogrammed AR sites in human tumor tissue. Introduction of FOXA1 and HOXB13 into an immortalized prostate cell line reprogrammed the AR cistrome to resemble that of a prostate tumor, functionally linking these specific factors to AR reprogramming. These findings offer mechanistic insights into a key set of events that drive normal prostate epithelium towards transformation and establish the centrality of epigenetic reprogramming in human prostate tumorigenesis.

Detecting metastatic prostate carcinoma in pelvic lymph nodes following neoadjuvant hormone therapy: the eyes have it!

AIMS

Residual cancer morphology in radical prostatectomies (RPs) after neoadjuvant hormone therapy includes inconspicuous cytology, and treated tumour cells can be difficult to identify in lymph nodes. The aim of this study was to evaluate the role of immunohistochemistry (IHC) in identifying occult lymph node metastases following neoadjuvant hormone treatment of prostate cancer.

METHODS AND RESULTS

One hundred and twenty-eight lymph nodes from 24 patients treated with neoadjuvant hormone therapy, including abiraterone acetate alone or combined with leuprolide, were stained with antibodies against keratin AE1/AE3, prostate-specific antigen (PSA), prostate-specific acid phosphatase (PrAP), androgen receptor (AR), and NKX3.1. IHC slides were scored 'blind', and then retrospectively compared with haematoxylin and eosin (H&E)-stained slides and pathology reports. IHC identified carcinoma in six lymph nodes from three patients. All metastases were positive for NKX3.1 and AR, five of six were positive for AE1/AE3, and three of six were positive for PSA; PrAP was negative in all metastatic foci. All six lymph node metastases had been identified by H&E staining at the time of RP.

CONCLUSIONS

These findings suggest that routine use of IHC on lymph nodes from neoadjuvant-treated prostate carcinomas is not necessary. Nevertheless, for suspicious small foci of atypical cells in neoadjuvant-treated lymph nodes, NKX3.1 and AR appear to have the greatest sensitivity.

Discovery and validation of a 30-gene expression signature to identify prostate cancer patients who are candidates for active surveillance

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Background: Considerable attention has been devoted to the search for biomarkers of aggressive prostate cancer. While many promising markers have been proposed, it is often unclear whether their ability to risk classify is adequate to reduce overtreatment of indolent cancers. We present and validate a gene expression signature that is highly specific for indolent disease and that, when combined with Gleason, improves upon the prognostic power of Gleason alone. Methods: A 30-gene signature of indolent disease was derived from a case-control sample of men (n=254) from the Health Professionals Follow-Up Study (HPFS) who were followed prospectively from cancer diagnosis for a median of 13.7 years. Cases were defined as men with prostate cancer who experienced a metastatic event or died of cancer during follow-up, while indolent controls survived at least 8 years without metastases. Whole-transcriptome gene expression was quantified from archival formalin-fixed, paraffin-embedded (FFPE) tumor tissue specimens acquired at prostatectomy. Genes were selected by a novel analytic strategy that maximizes a partial area under the curve (pAUC) to accurately identify indolent tumors. We validated the signature in two independent cohorts: the Physicians’ Health Study (PHS; n=150) and a Swedish Watchful Waiting cohort (WW; n=253) with respective median follow-up times of 14.4 and 9.0 years. Results: When compared to a model with Gleason alone, application of the signature to both validation data sets significantly improved prognostic accuracy as measured by pAUC (p=0.003 in PHS and p<0.001 in WW). Performance was particularly strong among men diagnosed with Gleason 7, where unit standard deviation increases in the signature score were associated with odds ratios of indolence of 5.24 (95% CI 2.21-15.75; p<0.001) and 2.37 (95% CI 1.45-4.19; p=0.001) in the PHS and WW cohorts, respectively. Conclusions: We present a signature of indolent prostate cancer that adds prognostic information beyond Gleason and has the potential to guide men to active surveillance and avoid overtreatment. Validation across both treated and untreated cohorts supports the discovery of a robust signature.

A phase Ib study of BKM120 combined with abiraterone acetate for castrate-resistant, metastatic prostate cancer

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Background: There is cross-talk between PI3-kinase (PI3K) pathway and androgen receptor (AR) signaling pathways, respectively, which are both critical for cell survival in castrate-resistant prostate cancer (CRPC). The primary study objective is to determine the safety profile and MTD of BKM120 (B, pan-PI3K inhibitor) in combination with abiraterone/prednisone (A/P) in CRPC patients. The secondary objectives are to assess the impact of PTEN status on duration of response/time to progression in the expansion cohort, and to evaluate the impact of B on a PI3-kinase activation fingerprint in metastatic bone or lymph node tissue samples. An exploratory objective is to assess the effect of B on transcription of a set of AR-regulated genes in metastatic bone biopsy samples. Methods: The trial design involves a 14 day lead-in phase with B alone, to assess single-agent toxicity and perform correlative studies. A/P is combined with B at the end of 14 days using the standard 3+3 dose-escalation design with 3 dose levels of B, and participants are assessed for safety and MTD on the combination therapy. To determine PD impact of single agent B on the PI3K activation signature at a metastatic site, a mandatory CT-guided bone or lymph node biopsy is performed prior to B initiation and at the end of 2 weeks on B single-agent therapy. Immunohistochemical (IHC) stains for three markers (p-AKT, p-S6 and PTEN) are used to obtain a semi-quantitative PI3K activation score, based on the quartile levels of continuous staining scores of each marker. Results: Patient 1 had symptomatic bone pain improvement, marked decline in narcotic pain requirements and a biochemical decline in PSA from 156.5 to a PSA nadir of 9.2 within 4 weeks of combination therapy. Patient 3 had a symptomatic and >90% biochemical improvement and has currently completed 15 cycles on treatment, and remains on study to date. RT-PCR analysis showed that the feedback circuitry between PI3K and AR signaling is heterogeneous in the metastatic prostate cancer-bone microenvironment, and dependent on tumor PTEN status. Conclusions: Preliminary data shows promising anti-tumor activity in CRPC patients from dual targeting of PI3K and AR pathways with B and A/P, respectively. Clinical trial information: NCT01741753.

FGFR3 expression in primary and metastatic urothelial carcinoma of the bladder

While fibroblast growth factor receptor 3 (FGFR3) is frequently mutated or overexpressed in nonmuscle-invasive urothelial carcinoma (UC), the prevalence of FGFR3 protein expression and mutation remains unknown in muscle-invasive disease. FGFR3 protein and mRNA expression, mutational status, and copy number variation were retrospectively analyzed in 231 patients with formalin-fixed paraffin-embedded primary UCs, 33 metastases, and 14 paired primary and metastatic tumors using the following methods: immunohistochemistry, NanoString nCounterTM, OncoMap or Affymetrix OncoScanTM array, and Gain and Loss of Analysis of DNA and Genomic Identification of Significant Targets in Cancer software. FGFR3 immunohistochemistry staining was present in 29% of primary UCs and 49% of metastases and did not impact overall survival (P = 0.89, primary tumors; P = 0.78, metastases). FGFR3 mutations were observed in 2% of primary tumors and 9% of metastases. Mutant tumors expressed higher levels of FGFR3 mRNA than wild-type tumors (P < 0.001). FGFR3 copy number gain and loss were rare events in primary and metastatic tumors (0.8% each; 3.0% and 12.3%, respectively). FGFR3 immunohistochemistry staining is present in one third of primary muscle-invasive UCs and half of metastases, while FGFR3 mutations and copy number changes are relatively uncommon.

SPINK1 protein expression and prostate cancer progression

PURPOSE

SPINK1 overexpression has been described in prostate cancer and is linked with poor prognosis in many cancers. The objective of this study was to characterize the association between SPINK1 overexpression and prostate cancer-specific survival.

EXPERIMENTAL DESIGN

The study included 879 participants in the U.S. Physicians' Health Study and Health Professionals Follow-Up Study, diagnosed with prostate cancer (1983-2004) and treated by radical prostatectomy. Protein tumor expression of SPINK1 was evaluated by immunohistochemistry on tumor tissue microarrays.

RESULTS

Seventy-four of 879 (8%) prostate cancer tumors were SPINK1 positive. Immunohistochemical data were available for PTEN, p-Akt, pS6, stathmin, androgen receptor (AR), and ERG (as a measure of the TMPRSS2:ERG translocation). Compared with SPINK1-negative tumors, SPINK1-positive tumors showed higher PTEN and stathmin expression, and lower expression of AR (P < 0.01). SPINK1 overexpression was seen in 47 of 427 (11%) ERG-negative samples and in 19 of 427 (4%) ERG-positive cases (P = 0.0003). We found no significant associations between SPINK1 status and Gleason grade or tumor stage. There was no association between SPINK1 expression and biochemical recurrence (P = 0.56). Moreover, there was no association between SPINK1 expression and prostate cancer mortality (there were 75 lethal cases of prostate cancer during a mean of 13.5 years follow-up; HR = 0.71; 95% confidence interval, 0.29-1.76).

CONCLUSIONS

Our results suggest that SPINK1 protein expression may not be a predictor of recurrence or lethal prostate cancer amongst men treated by radical prostatectomy. SPINK1 and ERG protein expression do not seem to be entirely mutually exclusive, as some previous studies have suggested.

Prostate-specific membrane antigen protein expression in tumor tissue and risk of lethal prostate cancer

BACKGROUND

Overexpression of prostate-specific membrane antigen (PSMA) in tumor tissue and serum has been linked to increased risk of biochemical recurrence in surgically treated prostate cancer patients, but none of the studies have assessed its association with disease-specific mortality.

METHODS

We examined whether high PSMA protein expression in prostate tumor tissue was associated with lethal disease, and with tumor biomarkers of progression, among participants of two U.S.-based cohorts (n = 902, diagnosed 1983-2004). We used Cox proportional hazards regression to calculate multivariable HRs and 95% confidence intervals (CI) of lethal prostate cancer, defined as disease-specific death or development of distant metastases (n = 95). Partial Spearman rank correlation coefficients were used to correlate PSMA with tumor biomarkers.

RESULTS

During an average 13 years of follow-up, higher PSMA expression at prostatectomy was significantly associated with lethal prostate cancer (age-adjusted HRQuartile(Q)4vs.Q1 = 2.42; Ptrend < 0.01). This association was attenuated and nonsignificant (multivariable-adjusted HRQ4vs.Q1 = 1.01; Ptrend = 0.52) after further adjusting for Gleason score and prostate-specific antigen (PSA) at diagnosis. High PSMA expression was significantly (P < 0.05) correlated with higher Gleason score and PSA at diagnosis, increased tumor angiogenesis, lower vitamin D receptor and androgen receptor expression, and absence of ets-related gene (ERG) expression.

CONCLUSIONS

High tumor PSMA expression was not an independent predictor of lethal prostate cancer in the current study. PSMA expression likely captures, in part, malignant features of Gleason grade and tumor angiogenesis.

IMPACT

PSMA is not a strong candidate biomarker for predicting prostate cancer-specific mortality in surgically treated patients.

Lymphatic and nerve distribution throughout the parametrium

BACKGROUND

Our objective was to concomitantly assess distribution of lymphatic and nerve structures in the parametrium.

METHODS

Twenty hemipelvises from ten fresh cadavers were dissected to differentiate between, three different parts of the parametrium: the lateral parametrium, the proximal and the distal part of the posterior parametrium. Histologic and immunofluorescence analyses of nerve and lymphatic structures were performed using NSE and LYVE-1 staining, respectively. The percentage of structures was independently scored as 0 (0%), 1 (1-20%), 2 (20-50%), 3 (50-80%), 4 (>80%).

RESULTS

The lateral parametrium and the proximal part of the posterior parametrium contained both nerve (scored 2.25 and 2.50, respectively) and lymphatic (scored 2.50 and 2.00, respectively) structures. The distal part of the posterior parametrium also contained numerous nerve structures (scored 2.00) but lymphatic structures were rare (scored 0.88). No difference in nerve distribution was found according to the parts of parametrium while a significantly lower distribution of lymphatic vessels was observed in the distal part of the posterior parametrium (p=0.03).

CONCLUSION

The distal part of the posterior parametrium is of high nerve density and low lymphatic density raising the issue as to whether it should be removed during radical hysterectomy.

A co-clinical approach identifies mechanisms and potential therapies for androgen deprivation resistance in prostate cancer

Here we report an integrated analysis that leverages data from treatment of genetic mouse models of prostate cancer along with clinical data from patients to elucidate new mechanisms of castration resistance. We show that castration counteracts tumor progression in a Pten-loss driven mouse model of prostate cancer through the induction of apoptosis and proliferation block. Conversely, this response is bypassed upon deletion of either Trp53 or Lrf together with Pten, leading to the development of castration resistant prostate cancer (CRPC). Mechanistically, the integrated acquisition of data from mouse models and patients identifies the expression patterns of XAF1-XIAP/SRD5A1 as a predictive and actionable signature for CRPC. Importantly, we show that combined inhibition of XIAP, SRD5A1, and AR pathways overcomes castration resistance. Thus, our co-clinical approach facilitates stratification of patients and the development of tailored and innovative therapeutic treatments.

Phase 2 study of dose-intense temozolomide in recurrent glioblastoma

BACKGROUND

Among patients with glioblastoma (GBM) who progress on standard temozolomide, the optimal therapy is unknown. Resistance to temozolomide is partially mediated by O(6)-methylguanine-DNA methyltransferase (MGMT). Because MGMT may be depleted by prolonged temozolomide administration, dose-intense schedules may overcome resistance.

METHODS

This was a multicenter, phase 2, single-arm study of temozolomide (75-100 mg/m(2)/day) for 21 days of each 28-day cycle. Patients had GBM in first recurrence after standard therapy. The primary end point was 6-month progression-free survival (PFS6).

RESULTS

Fifty-eight participants were accrued, 3 of whom were ineligible for analysis; one withdrew before response assessment. There were 33 men (61%), with a median age of 57 years (range, 25-79 years) and a median Karnofsky performance score of 90 (range, 60-100). Of 47 patients with MGMT methylation results, 36 (65%) had methylated tumors. There were 7 (13%) partial responses, and PFS6 was only 11%. Response and PFS did not depend on MGMT status; MSH2, MLH1, or ERCC1 expression; the number of prior temozolomide cycles; or the time off temozolomide. Treatment was well tolerated, with limited grade 3 neutropenia (n = 2) or thrombocytopenia (n = 2).

CONCLUSIONS

Dose-intense temozolomide on this schedule is safe in recurrent GBM. However, efficacy is marginal and predictive biomarkers are needed.

Relationship of ERCC1 genotype variant with mRNA expression and ERCC1 protein levels in advanced urothelial carcinoma (UC)

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Background: DNA repair factors may be predictive for response to chemotherapies that produce DNA damage. While low ERCC1 protein and mRNA levels have been reported as associated with improved outcomes in metastatic UC patients treated with platinum-based chemotherapy, the relationship between genotype, mRNA expression, and protein level is unknown. The ERCC1 germline 19007C>T single-nucleotide polymorphism (SNP) is functionally associated with reduced translation of ERCC1 mRNA. We investigated the relationship between ERCC1 germline SNP, ERCC1 tumor mRNA and protein expression, in a cohort of patients with advanced UC who received first-line, platinum-based chemotherapy. Methods: A cohort of clinically annotated, uniformly-treated advanced UC patients with FFPE primary tumor tissue available was identified through the Hellenic cooperative Oncology Group (HECOG) (N=93). Genomic DNA extraction, nested PCR, and restriction fragment length polymorphism techniques for the 19007C>T SNP were performed to identify C/C, C/T and T/T genotypes. ERCC1 mRNA expression was interrogated using Nanostring nCounter profiling. IHC analysis was performed on tissue arrays using an ERCC1 antibody. Percent of positive nuclear staining was categorized as quartiles using previously identified cut-points. Results: ERCC1 C/T genotype was identified in 30/61 samples (49%) and T/T in 14/61 samples (23%). In 54 patients with both SNP and mRNA data available, T/T genotype was associated with the highest level of mRNA expression, followed by the C/T genotype (p=0.04). Neither ERCC1 genotype (N=44) nor ERCC1 mRNA expression (N=54) was associated with ERCC1 protein expression as measured by IHC (p=0.52 and p=0.13, respectively). Conclusions: ERCC1 19007C>T is associated with increased ERCC1 mRNA expression. However, neither genotype nor mRNA are surrogates for ERCC1 protein detected by IHC in advanced UC tumors. This suggests that while genotype influences mRNA expression of ERCC1, the use of the nucleotide excision repair pathway as a predictive biomarker of platinum-sensitivity may be more complex than previously appreciated and require the integrative use of proteomics, genomics and epigenomics.

Multidimensional investigation of HER2 in advanced urothelial carcinoma (UC)

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Background: Incidence of Her2 positivity and association with overall survival (OS) are controversial in advanced UC. Activating Her2 mutations have been identified in other cancers, but they have not been previously reported in UC. We determined Her2 status by immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and copy number gain (CNG) via array CGH of primary UC tumors from patients (pts) with metastatic disease. Targeted Her2 sequencing was performed at known mutation hotspots, and mutation effect was investigated in vitro. Methods: Tissue microarrays of formalin fixed paraffin-embedded tumor from 98 UC pts treated with platinum-based combination chemotherapy for metastatic disease were evaluated for Her2 protein and for Her2 gene amplification by using standard clinical protocols. Positive staining was defined as an IHC score of 3+ or a FISH ratio of ≥2 using scoring criteria established for evaluation of breast cancer. Her2 CNG was evaluated by aCGH with cutoff log base 2 ratio > 0.9. Mutation status was validated by hME sequencing. OS was measured from start of treatment for metastatic disease. Association of OS and Her2 status was assessed by a Cox regression model. NIH-3T3 cells with Her2 V777L were assessed for growth, invasion, and Her2 kinase activation. Results: 22% of pts had 3+ Her2 staining by IHC. 21% of pts had FISH amplification. These were concordant in 78% of pts. CNG was identified in 16% and was concordant with FISH and IHC 85% and 88% of the time, respectively. Her2 status by any modality showed no significant association with OS in either univariate [HR=0.94, 95% CI: (0.52, 1.70), p=0.83] or multivariate [HR=1.12, 95% CI: (0.61, 2.06), p=0.72] analysis. Her2 mutations (V777L and L755S) were identified in 2 pts (2%). In vitro analysis of V777L results in transformation of NIH-3T3 cells, leading to increased growth, invasion on soft agar, and Her2 kinase constitutive activation. Conclusions: Her2 overexpression or amplification in the primary tumor does not predict OS in pts with metastatic UC. Other research has suggested that V777L sensitizes cells to lapatinib, while L755S leads to lapatinib resistance. These rare oncogenic Her2 mutations occur and may be therapeutic targets in selected pts.

FGFR3 protein expression and gene mutation in primary and metastatic urothelial carcinoma (UC) tumors

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Background: FGFR3 protein expression may represent a valid therapeutic target in metastatic UC. The prevalence of both mutation and overexpression is unknown in metastatic UC. Methods: Tissue microarrays of formalin fixed paraffin-embedded urothelial carcinomas (UC) were stained for FGFR3 by immunohistochemistry (IHC) [primary (n=250); metastatic (n=31); of which (n=14) were paired]. FGFR3 immunostaining was scored as negative or positive based on previously reported scoring systems. FGFR3 mutation in primary tumors was assessed by iPlex and confirmed by hME sequencing (n=141) or Affymetrix OncoScan FFPE Express 2.0 (primary: n=17; metastases n=31). Results: FGFR3 IHC positivity was present in 48% of metastases (95% CI=32-65%) and 26% of primary tumors, (95%=CI 21-32%), though strong staining was rare (<1%). Paired primary and metastatic tumors were both negative in 50% of cases, with 14% positive only in the metastasis, 14% positive only in the primary tumor, and 21% positive in both. If the primary tumor showed staining, 71% of the metastases showed staining. FGFR3 IHC staining did not impact overall survival (p=0.8). FGFR3 mutations were observed in 9.6% of metastatic tumors (95% CI=3.3-25%), compared to 3.5% of primary tumors (95% CI=1.5%-8%). Co-occurrence of mutation and FGFR3 DNA copy number gain was observed in one specimen. Conclusions: FGFR3 IHC staining is present 26 % of primary tumors of patients who go on to develop metastatic disease, and nearly half of metastatic tumor sites. FGFR3 mutation frequency in primary and metastatic tumor specimens is low. Further investigation of the frequency of FGFR3 protein expression in metastases is needed. The presence of FGFR3 protein by IHC staining in primary and metastatic specimens suggests that FGFR3 may represent a therapeutic target even in the absence of mutation. Further functional studies are needed.

Association of DNA repair factors with overall survival in advanced urothelial carcinoma treated with platinum-based chemotherapy

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Background: DNA repair factors are hypothesized to mediate chemosensitivity to cytotoxic agents that produce DNA damage and may be predictive for response to platinum-based chemotherapeutic regimens. Primary urothelial carcinoma (UC) tumors of patients who developed metastatic disease were evaluated for expression of a panel of DNA repair factors by immunohistochemistry (IHC).

Methods: A cohort of 132 clinically annotated, uniformly-treated (platinum-based combination chemotherapy) UC patients who subsequently developed distant metastases with FFPE primary tumor tissue available was identified. Tumor bearing areas were evaluated by a single urologic pathologist. Tissue arrays were constructed for IHC analysis of the following DNA repair factors: ERCC1, Rad 51, BRCA1/2, PAR and PARP1. Tumor was deparaffinized and specific antigen retrieval determined for individual antibodies. Pathologist supervised IHC analysis of nuclear versus cytoplasmic expression was performed using spectral imaging analysis. Overall survival (OS) was defined from start of chemotherapy for metastatic disease to death (N=67) or censored on the last known alive date. Percent of positive nuclear staining was categorized as quartiles or previously identified cut-points. Cox regression evaluated the associations of percent positive nuclear staining levels and OS in multivariable analysis (HRs and 95% CIs included) that controlled for known prognostic variables (performance status and visceral metastases).

Results: Higher percentage of nuclear staining of ERCC1 [HR=2.7 (1.5, 4.9), p=0.0007]; Rad51 [HR=5.6 (1.7, 18.3), p=0.005]; and PAR [HR=2.2 (1.1, 4.4), p=0.026] in tumor tissue were associated with poor outcome; each was independent of the other two repair factors and known prognostic variables. Neither nuclear nor cytoplasmic staining for BRCA1/2 or PARP1 reached statistical significance for an association with OS.

Conclusions: DNA damage repair factor levels measured by IHC impact outcomes in advanced UC. External validation is ongoing and will be presented. Further studies are required to determine whether these biomarkers are prognostic or predictive in this setting.

Vitamin D receptor protein expression in tumor tissue and prostate cancer progression

PURPOSE

Data suggest that circulating 25-hydroxyvitamin D [25(OH)D] interacts with the vitamin D receptor (VDR) to decrease proliferation and increase apoptosis for some malignancies, although evidence for prostate cancer is less clear. How VDR expression in tumor tissue may influence prostate cancer progression has not been evaluated in large studies.

PATIENTS AND METHODS

We examined protein expression of VDR in tumor tissue among 841 patients with prostate cancer in relation to risk of lethal prostate cancer within two prospective cohorts, the Physicians' Health Study and Health Professionals Follow-Up Study. We also examined the association of VDR expression with prediagnostic circulating 25(OH)D and 1,25-dihydroxyvitamin D levels and with two VDR single nucleotide polymorphisms, FokI and BsmI.

RESULTS

Men whose tumors had high VDR expression had significantly lower prostate-specific antigen (PSA) at diagnosis (P for trend < .001), lower Gleason score (P for trend < .001), and less advanced tumor stage (P for trend < .001) and were more likely to have tumors harboring the TMPRSS2:ERG fusion (P for trend = .009). Compared with the lowest quartile, men whose tumors had the highest VDR expression had significantly reduced risk of lethal prostate cancer (hazard ratio [HR], 0.17; 95% CI, 0.07 to 0.41). This association was only slightly attenuated after adjustment for Gleason score and PSA at diagnosis (HR, 0.33; 95% CI, 0.13 to 0.83) or, additionally, for tumor stage (HR, 0.37; 95% CI, 0.14 to 0.94). Neither prediagnostic plasma vitamin D levels nor VDR polymorphisms were associated with VDR expression.

CONCLUSION

High VDR expression in prostate tumors is associated with a reduced risk of lethal cancer, suggesting a role of the vitamin D pathway in prostate cancer progression.

Fatty acid synthase polymorphisms, tumor expression, body mass index, prostate cancer risk, and survival

PURPOSE

Fatty acid synthase (FASN) regulates de novo lipogenesis, body weight, and tumor growth. We examined whether common germline single nucleotide polymorphisms (SNPs) in the FASN gene affect prostate cancer (PCa) risk or PCa-specific mortality and whether these effects vary by body mass index (BMI).

METHODS

In a prospective nested case-control study of 1,331 white patients with PCa and 1,267 age-matched controls, we examined associations of five common SNPs within FASN (and 5 kb upstream/downstream, R(2) > 0.8) with PCa incidence and, among patients, PCa-specific death and tested for an interaction with BMI. Survival analyses were repeated for tumor FASN expression (n = 909).

RESULTS

Four of the five SNPs were associated with lethal PCa. SNP rs1127678 was significantly related to higher BMI and interacted with BMI for both PCa risk (P(interaction) = .004) and PCa mortality (P(interaction) = .056). Among overweight men (BMI > or = 25 kg/m(2)), but not leaner men, the homozygous variant allele carried a relative risk of advanced PCa of 2.49 (95% CI, 1.00 to 6.23) compared with lean men with the wild type. Overweight patients carrying the variant allele had a 2.04 (95% CI, 1.31 to 3.17) times higher risk of PCa mortality. Similarly, overweight patients with elevated tumor FASN expression had a 2.73 (95% CI, 1.05 to 7.08) times higher risk of lethal PCa (P(interaction) = .02).

CONCLUSION

FASN germline polymorphisms were significantly associated with risk of lethal PCa. Significant interactions of BMI with FASN polymorphisms and FASN tumor expression suggest FASN as a potential link between obesity and poor PCa outcome and raise the possibility that FASN inhibition could reduce PCa-specific mortality, particularly in overweight men.

Abstract PR-01: Vitamin D receptor expression is inversely associated with prostate cancer progression

Background: Vitamin D is inversely associated with risk of several malignancies. Circulating vitamin D interacts with the vitamin D receptor (VDR) at the cellular level to inhibit proliferation, increase apoptosis and decrease angiogenesis. Thus, although vitamin D levels appear to be unrelated to total prostate cancer incidence, VDR levels in tumor tissue may influence prostate cancer prognosis.

Methods: We examined the immunohistochemical expression of VDR on archival tumor tissue from 841 prostate cancer cases diagnosed between 1982 and 2004 within two ongoing, prospective cohorts: the Physicians' Health Study and Health Professionals Follow-up Study. VDR expression was measured quantitatively using the CRi Vectra™ system. We used Cox proportional hazards regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of VDR expression with lethal prostate cancer (N=73) through 2008. On a subset of cases, we also examined correlation of tumor VDR expression with circulating 25(OH)D3 and 1alpha,25(OH)2D3 measured at baseline (N=84) in 1982 and two SNPs in VDR: Fok1 and bsm1 (N=140).

Results: Men with high tumor VDR expression had significantly lower Gleason score, lower prostate specific antigen (PSA) levels at diagnosis, and were less likely to have advanced tumor stage (p=0.008, p=0.012, p=0.001, respectively). Compared to the lowest quartile, men in the highest quartile of VDR expression were at significantly lower risk of developing lethal prostate cancer (age-adjusted HRs across quartiles Q2=0.95, 95% CI: 0.51–1.79; Q3=0.93, 95% CI: 0.49–1.76; Q4 = 0.23, 95% CI:0.09–0.55). This association was attenuated (HRQ4vsQ1 = 0.42, 95% CI: 0.16–1.09) after further adjustment for pathological tumor stage, Gleason grade, and PSA level at diagnosis. Tumors expressing high levels of VDR had modest downregulation of cell proliferation as measured by Ki67 (r=-0.11). Moreover, expression of estrogen receptor alpha (r=0.40, p&lt;0.001) and androgen receptor (r=0.41, p&lt;0.001) were positively correlated with VDR expression. Neither prediagnostic plasma vitamin D levels nor gene variants in VDR were associated with VDR protein expression in tumors.

Conclusion: In this large prospective study, men with tumors that demonstrated upregulation of VDR had significantly improved clinical features and reduced risk of lethal prostate cancer. In line with experimental studies, the positive correlation between VDR expression, and androgen receptor and estrogen receptor provides evidence that that VDR acts in an androgen- and/or estrogen-dependent manner. These data highlight the potential role of the vitamin D system in preventing prostate cancer progression.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-01.

Inhibition of inducible nitric oxide synthase activity prevents liver recovery in rat thioacetamide-induced fibrosis reversal

BACKGROUND

Stimulation of nitric oxide (NO) synthesis similar to the application of NO donors could be of benefit in liver fibrosis. Many authors believe that activation of NO synthesis by pharmacological agents is promising in the treatment of liver fibrosis. However, there is considerable controversy in understanding the role of NO in fibrogenesis and fibrolysis. The aims of our study were to evaluate the effects of L-arginine, as an NO metabolic precursor, and those of NO synthase (NOS) inhibitors, L-nitroarginine methyl ester (L-NAME) and aminoguanidine (AG) in rats with thioacetamide (TAA)-induced liver fibrosis reversal.

MATERIALS AND METHODS

Male Wistar rats, 230-240 g, received TAA (200 mg kg(-1), intraperitoneally) twice a week for 3 months. Liver resolution was simulated by withdrawal of TAA administration. Thereafter the animals were subdivided into five groups and treated by intragastric intubation with: L-arginine (100 and 300 mg kg(-1)); L-NAME as an inhibitor of both constitutively expressed NOS (eNOS) and inducible NOS (iNOS) (20 mg kg(-1)), AG as a specific inhibitor of iNOS (100 mg kg(-1)) or placebo. The severity of liver fibrosis was assessed by morphometric evaluation of liver slides stained with Azan-Mallory, hydroxyproline (Hyp) determination and mRNA steady state levels of collagen I, transforming growth factor (TGF)-beta1, metalloproteinases (MMP)-13, -14, tissue inhibitor of MMP (TIMP)-1 and plasminogen activator inhibitor (PAI)-1 were quantified by real time PCR. The activities of serum marker enzyme, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase, were measured.

RESULTS

TAA treatment during 3 months induced micronodular liver fibrosis with a pronounced deposition of collagen fibres. L-Arginine did not affect this deposition nor did it affect both relative and total liver hydroxyproline content. Both NOS inhibitors significantly increased the square of the liver connective tissue stained by Azan-Mallory and the above parameters characterizing liver hydroxyproline content. Both NOS inhibitors up-regulated procollagen alpha1 (I), MMP-13, TIMP-1 and PAI-1 mRNA expression. The AG effects were more pronounced. than those of L-NAME. AG treatment also increased mRNA expression of TGF-beta1 and PAI-1.

CONCLUSIONS

Both NOS inhibitors developed a clear pro-fibrotic effect in the liver. Aminoguanidine was more fibrotic than L-NAME. Our data suggest a significant anti-fibrotic role for iNOS rather than for eNOS. L-Arginine did not show any anti-fibrotic properties in the TAA-model used.

Shc test as a strong prognostic indicator of disease outcome in early stage gastric cancer

10090

Background: Treatment planning for gastric cancer is primarily based on clinical staging of disease. Markers predicting likelihood of disease outcome would help guide treatment decisions, especially for early stage disease. The Shc proteins, implicated in many aggressive cancers, and measured in tumor specimens by the immunohistochemical (IHC) Shc Test, have shown strong ability to predict disease outcome in breast cancer. We report here that the Shc Test is a strong prognostic indicator of disease outcome in early stage gastric cancer. Methods: Histopathology was examined in one hundred and seventeen (117) primary gastric cancer patient samples from Rhode Island Hospital in tissue microarray format (21 disease recurrences; 63 disease-specific deaths; average follow-up of 2.7 yrs). IHC staining of the Shc proteins was independently scored on a 0–5 scale by two pathologists, blinded to patient information. Results: Stage I or II gastric cancers (n=62) could be clearly separated at a cutpoint of 1.1 on a 0–5 scale, into good prognosis (16% 4yr relapse risk; demonstrating high PY-Shc) and poor prognosis (46% 4yr relapse risk; showing low PY-Shc) (log-rank, P=0.003). p66 Shc showed similar prognostic abilities. High PY-Shc in patients with early stage disease showed a significant protective effect on overall survival (P=0.003) by univariate log rank analysis. As a continuous variable, PY-Shc had a strong predictive ability (HR = 0.09, P=0.055) that approached significance. By univariate Cox proportional hazards, patients with high PY-Shc had a 5-fold reduction in disease specific death (DSD) compared to patients with low PY-Shc (P=0.002). By multivariate Cox proportional hazards, adjusted for grade, stage, chemotherapy and radiation therapy, only PY-Shc (HR = 0.22, P=0.015) and Intestinal tumor type (HR = 0.38, P=0.046) remained as significant predictors of survival. Conclusions: The Shc Test shows a strong prognostic ability to stratify early stage gastric cancer patients by risk, making it a valuable tool in selecting therapy for these patients.

[Table: see text]

Effect of the nitric oxide donor and the nitric oxide synthase inhibitor on the liver of rats with chronic hepatitis induced by dimethylnitrosamine

The present study was designed to examine the effects of the donor of nitric oxide (NO), NaNO(2) and the inhibitor of NO synthase, N(omega)-nitro-L-arginine (L-NNA), on the development of dimethylnitrosamine (DMNA)-induced chronic hepatitis in rats. L-NNA decreased rat survival and enhanced the severity of hepatic encephalopathy in the DMNA-treated animals. The aggravation of the morphological signs of hepatitis, the activation of serum alanine aminotransferase and cytosolic superoxide dismutase activities and the increase in the liver malondialdehyde content were observed in this group. The treatment with NaNO(2) improved liver morphology, decreased serum marker enzyme activities, lowered the activities of alpha-D-mannosidase and N-acetyl-beta-D-glucosaminidase compared to the DMNA-treated group. The results of the morphological and biochemical studies suggest that L-NNA increased DMNA-induced liver damage, whereas NaNO(2) partially prevented the development of chronic hepatitis. It is proposed that the opposite effects of L-NNA and NaNO(2) are partially explained by a modulation of the free radical-dependent processes in the liver.

Synthesis, cardiac electrophysiology, and .beta.-blocking activity of novel arylpiperazines with potential as class II/III antiarrhythmic agents

A series of novel arylpiperazines have been prepared in an attempt to incorporate both class II (beta-receptor blocking) and class III antiarrhythmic properties in a single molecule. The key step in the preparation of the new compounds involves a regioselective heterocyclic ring formation. All but four compounds significantly prolonged action potential duration in canine cardiac Purkinje fibers (class III activity). All but one of the compounds demonstrated beta-receptor affinity in a competitive binding assay and three had beta 1-receptor selectivity. Compared to sotalol, a reference class II/III agent, arylpiperazine 7a (4-[(methylsulfonyl)amino]-N-[(4- phenylpiperazin-2-yl)methyl]benzamide) demonstrated beta 1-selectivity and was 1 order of magnitude more potent in the in vitro class III and the beta 1-receptor screens. Compound 7a was evaluated further and found to be effective in preventing programmed electrical stimulation-induced arrhythmias in conscious dogs (class III activity) and against epinephrine-induced arrhythmias in halothane anesthetized dogs (class II activity).

Solitary neurofibroma of the mandible and infratemporal fossa in a young child. Report of a case

The first case of a rare and unusual solitary neurofibroma of the mandible that caused bony erosion and extension into the adjacent soft tissues of the infratemporal fossa is presented. The clinical, radiographic, and histopathologic features of the neurofibroma are reviewed. The diagnostic procedures and the surgical treatment of this tumor in a young child are discussed.

Synthesis of novel (aryloxy)propanolamines and related compounds possessing both class II and class III antiarrhythmic activity

Several (aryloxy)propanolamines and related compounds (i.e. 5-13, 16-18, 20-24, 27-33, 35, 37-39, 41, and 42) were synthesized and investigated for their class III electrophysiological activity and class II (beta-blocking) effects with use of in vitro and in vivo models. Structure-activity relationships are discussed for a series of 30 compounds. A number of these compounds prolonged the action potential duration at 95% repolarization of isolated canine cardiac Purkinje fibers by 20% (C20APD95) at concentrations of less than 1.0 microM, with no significant effects on cardiac conduction. beta-Adrenergic receptor binding studies showed that some of these compounds were 2-20 times more potent for cardiac beta 1 receptors than for beta 2 receptors. In particular, compounds 32, 41, 1, and especially (S)-1 were found to be orally active class III agents in anesthetized mongrel dogs (1 or 3 mg/kg, id) and efficacious at suppressing programmed electrical stimulation induced arrhythmias in halothane-anesthetized dogs. The profile of these compounds was similar to that found for sotalol. Compound (S)-1, which was more potent than sotalol in the PES study and equieffective in the halothane/epinephrine dog model, is being investigated further as a combined class III/II antiarrhythmic agent.

Synthesis and cardiac electrophysiological activity of N-substituted-4-(1H-imidazol-1-yl)benzamides--new selective class III agents

The synthesis and cardiac electrophysiological activity of 18 N-substituted imidazolylbenzamides or benzene-sulfonamides are described. Compounds 6a,d,f-k and 11 exhibited potency in the in vitro Purkinje fiber assay comparable to that of N-[2-(diethylamino)ethyl]-4- [(methylsulfonyl)amino]benzamide (1, sematilide), a potent selective class III agent which is undergoing clinical trials. These data indicate that the 1H-imidazol-1-yl moiety is a viable replacement for the methylsulfonylamino group for producing class III electrophysiological activity in the N-substituted benzamide series. N-[2-(Diethylamino)ethyl]-4-(1H-imidazol-1-yl)benzamide dihydrochloride (6a) was further studied in two in vivo models of reentrant arrhythmias and showed potency and efficacy comparable to those of 1.

Synthesis and cardiac electrophysiological activity of 2- and 3-[(substituted phenyl)alkyl]quinuclidines. Structure-activity relationships

The syntheses and cardiac electrophysiological effects of 21 2- and 3-substituted quinuclidines and some quaternary ammonium derivatives are described. The 2-substituted quinuclidines 2-8 were prepared by alkylation of 2-methylene-3-quinuclidinone. The Wittig reaction with 3-quinuclidinone afforded the 3-substituted derivative 9, which was subsequently converted to 10 and 11. The electrophysiological profiles of the compounds were determined in canine cardiac Purkinje fibers and ventricular muscle strips. The 3-[(substituted phenyl)alkyl]quinuclidines selectively increased action potential duration (Vaughan Williams class III activity). In the 2-substituted series some of the compounds both increased action potential duration and decreased conduction velocity (class I activity). For some of the 2-substituted quinuclidines, appropriate substitution of the phenyl ring was shown to be a requirement for significant class III electrophysiological activity. Selected compounds were efficacious in a programmed electrical stimulation model in the anesthetized dog.

Synthesis and antiarrhythmic activity of novel 3-alkyl-1-[omega-[4-[(alkylsulfonyl)amino]phenyl]-omega- hydroxyalkyl]-1H-imidazolium salts and related compounds. 2

Novel analogues of the class III antiarrhythmic agent 1-[2-hydroxy-2-[4-[(methylsulfonyl)amino]phenyl]ethyl]-3-methyl-1H- imidazolium chloride, 1 (CK-1649), were prepared and investigated for their class III electrophysiological activity on isolated canine cardiac Purkinje fibers and ventricular muscle tissue. Structure-activity relationships are discussed for a series of 11 compounds. One compound, N-[4-[1-hydroxy-2-(4,5-dihydro-2-methyl-1H-imidazol-1- yl)ethyl]phenyl]methanesulfonamide hydrochloride, 9, was comparable in activity to 1 in vitro and prolonged the functional refractory period in anesthetized dogs when given intraduodenally. Unlike 1, compound 9 was ineffective at preventing ventricular tachycardia induced by programmed electrical stimulation in anesthetized dogs 24 h after an acute myocardial infarction.

Synthesis and antiarrhythmic activity of novel 3-alkyl-1-[omega-[4-[(alkylsulfonyl)amino]phenyl]-omega- hydroxyalkyl]-1H-imidazolium salts and related compounds

Novel 3-alkyl-1-[omega-[4-[(alkylsulfonyl)amino]phenyl]-omega-hydroxyalkyl]-1H -imidazolium salts were synthesized and investigated for their class III electrophysiological activity on isolated canine cardiac Purkinje fibers and ventricular muscle tissue. Structure-activity relationships are discussed for a series of 25 compounds. Compound 3, 1-[2-hydroxy-2-[4-[(methylsulfonyl)amino]phenyl]ethyl]-3-methyl-1H- imidazolium chloride, prolonged the functional refractory period in anesthetized dogs when given intraduodenally and was also effective in preventing reentrant ventricular tachycardia induced by programmed electrical stimulation when administered intravenously in anesthetized dogs 24 h after an acute myocardial infarction. Both enantiomers of 3 were synthesized. No enantioselectivity was found in the electrophysiological effects of 3.

The effect of economic incentives on the education and distribution of physicians: a review

This paper examines the available evidence on the impact of economic factors on the specialty and locational choices of physicians. Economic variables which influence the "rate of return" to the physician (profitability in relation to training costs) to alternative specialties and locational decisions include average yearly income, hours of work, price for each health service and training costs. The findings of the review indicate that the rate of return to specialty training varies substantially among specialties. Rates of return to training in surgery and radiology are nearly three times that of other medical specialties. These rates of return differences are shown to have a small, albeit significant, effect on a physician's specialty as well as location choices. Furthermore, there is a positive relationship between the mean fees of physicians and the physician population ratio in an area, i.e., areas with more physicians have higher fees. Confounding the relationship between economic variables and specialty and locational choice is the fact that physicians may have substantial amounts of market power and can themselves influence the price of their services. Thus, the influence of reimbursement policies to alter the distribution of physicians may be less effective because physicians may have the ability to influence and alter the level of income and rate of return to training.