Daniel Saltzstein

Clinical utility of a biopsy-based cell cycle gene expression assay in localized prostate cancer

Abstract Objective: The CCP signature test (Prolaris) quantifies a patient’s risk of disease progression and prostate cancer specific mortality using a gene-expression-based cell cycle progression (CCP) score. This study evaluated the potential clinical utility of the CCP test in a US-based clinical setting. Methods: Urologists who participated in a prospective clinical study were sent a retrospective questionnaire to assess the value of the CCP test result. Fifteen board-certified urologists participated in the study, representing 15 distinct community urology group practices. Questionnaires were received for 294 evaluable patients. All patients had localized prostate cancer (T1–T3b, N0, M0). Results: Physicians found the CCP score valuable and indicated that 55% of tests generated a mortality risk that was either higher or lower than expected. Physicians also indicated that 32% of test results would lead to a definite or possible change in treatment. The data suggest that the test would have the net effect of shifting patients from more aggressive treatment to more conservative treatment. This was evidenced by the significant association between change in treatment and lower CCP scores (p < 0.002) and by the fact that 62% of tests likely to lead to a definite or possible change in treatment had mortality risks lower than the physician expected versus only 10% with risks higher than expected. Study limitations: This study measured the retrospectively assessed likelihood of change in treatment as estimated by the physician, not the actual change in treatment. Conclusions: The CCP score adds meaningful new information to risk assessment for localized prostate cancer patients. Real-world use of the test is likely to lead to a change in treatment in a significant portion of tested patients, particularly by shifting patients towards more conservative management. This could reduce overtreatment of patients with less aggressive disease, decreasing patient morbidity and costs for payers and the healthcare system.

Clinical utility of the Prostate Health Index ( phi ) for biopsy decision management in a large group urology practice setting

BackgroundDeciding when to biopsy a man with non-suspicious DRE findings and tPSA in the 4–10 ng/ml range can be challenging, because two-thirds of such biopsies are typically found to be benign. The Prostate Health Index (phi) exhibits significantly improved diagnostic accuracy for prostate cancer detection when compared to tPSA and %fPSA, however only one published study to date has investigated its impact on biopsy decisions in clinical practice.MethodsAn IRB approved observational study was conducted at four large urology group practices using a physician reported two-part questionnaire. Physician recommendations were recorded before and after receiving the phi test result. A historical control group was queried from each sites electronic medical records for eligible men who were seen by the same participating urologists prior to the implementation of the phi test in their practice. 506 men receiving a phi test were prospectively enrolled and 683 men were identified for the historical control group (without phi). Biopsy and pathological findings were also recorded for both groups.ResultsMen receiving a phi test showed a significant reduction in biopsy procedures performed when compared to the historical control group (36.4% vs. 60.3%, respectively, P < 0.0001). Based on questionnaire responses, the phi score impacted the physician’s patient management plan in 73% of cases, including biopsy deferrals when the phi score was low, and decisions to perform biopsies when the phi score indicated an intermediate or high probability of prostate cancer (phi ≥36).Conclusionsphi testing significantly impacted the physician’s biopsy decision for men with tPSA in the 4–10 ng/ml range and non-suspicious DRE findings. Appropriate utilization of phi resulted in a significant reduction in biopsy procedures performed compared to historical patients seen by the same participating urologists who would have met enrollment eligibility but did not receive a phi test.

A Phase II Randomized, Double-blind, Presurgical Trial of Polyphenon E in Bladder Cancer Patients to Evaluate Pharmacodynamics and Bladder Tissue Biomarkers

We performed a phase II pharmacodynamic prevention trial of Polyphenon E [a green tea polyphenol formulation primarily consisting of epigallocatechin gallate (EGCG)] in patients prior to bladder cancer surgery. Patients with a bladder tumor were randomized to receive Polyphenon E containing either 800 or 1,200 mg of EGCG or placebo for 14 to 28 days prior to transurethral resection of bladder tumor or cystectomy. The primary objective was to compare the postintervention EGCG tissue levels in patients receiving Polyphenon E as compared with placebo. Secondary objectives included assessments of tissue expression of PCNA, MMP2, clusterin, VEGF, p27, IGF-1, IGFBP-3; correlation of tissue, plasma, and urine levels of EGCG; and EGCG metabolism by catechol-O-methyltransferase and UDP-glucuronosyltransferase pharmacogenomic mutations. Thirty-one patients (male:female, 26:5; mean age, 67.2 years) were randomized and 29 (94%) completed the study. There was not an observed significant difference (P = 0.12) in EGCG tissue levels between two Polyphenon E dosage groups combined versus placebo. However, a dose–response relationship for EGCG levels was observed in both normal (P = 0.046) and malignant bladder tissue (P = 0.005) across the three study arms. In addition, EGCG levels in plasma (P < 0.001) and urine (P < 0.001) increased and PCNA (P = 0.016) and clusterin (P = 0.008) were downregulated in a dose-dependent fashion. No pharmacogenomic relationship was observed. EGCG levels in plasma, urine, and bladder tissue followed a dose–response relationship, as did modulation of tissue biomarkers of proliferation and apoptosis. Despite the limitations of this pilot study, the observed pharmacodynamics and desirable biologic activity warrant further clinical studies of this agent in bladder cancer prevention. Cancer Prev Res; 10(5); 298–307. ©2017 AACR.

Phase Ib placebo-controlled, tissue biomarker trial of diindolylmethane (BR-DIMNG) in patients with prostate cancer who are undergoing prostatectomy.

Epidemiologic, preclinical, and early phase I studies of the cruciferous vegetable bioactive metabolite, 3,3′-diindolylmethane (DIM), support its potential prostate cancer chemopreventive ability. We performed a multicenter, double-blind, placebo-controlled trial of DIM in patients diagnosed with prostate cancer and scheduled for radical prostatectomy. A total of 45 patients with organ-confined prostate cancer were randomized to 21–28 days of an absorption-enhanced formulation of DIM (BR-DIMNG) at doses of 100 or 200 mg per os twice daily or to placebo twice daily. Prostate tissue levels of DIM were the primary endpoint, with selected secondary biomarker endpoints including blood levels of DIM, total prostate-specific antigen, testosterone, and the insulin-like growth factor-1: insulin-like growth factor binding protein-3 ratio and the urinary 2-hydroxyestrone/16-hydroxyestrone ratio, obtained at baseline, at day 15, and before surgery, as well as tissue expression of androgen receptor, prostate-specific antigen, Ki67, caspase 3 with cytochrome p450 mRNA expression and genotyping (polymorphisms). DIM was well tolerated with excellent study compliance and relatively rapid accrual of all 45 patients within 1 year. DIM levels were detected in only seven of 28 prostate tissue specimens. There was a statistically significant difference in the change in the urinary 2-hydroxyestrone/16-hydroxyestrone ratio from baseline until before surgery between the placebo and 400 mg DIM groups, with otherwise statistically nonsignificant changes in plasma biomarker expression. The administration of BR-DIMNG to prostate cancer patients before prostatectomy yields detectable plasma levels but without consistent or significant tissue accumulation or biomarker modulation. This study demonstrates the feasibility of biologic evaluation of relatively nontoxic preventive agents in the preprostatectomy setting with the potential for rapid accrual.

Development of a reliable assay to measure glypican-1 in plasma and serum reveals circulating glypican-1 as a novel prostate cancer biomarker

Prostate cancer is responsible for hundreds of thousands of annual deaths worldwide. The current gold standard in early detection of prostate cancer, the prostate specific antigen test, boasts a high sensitivity but low specificity, resulting in many unnecessary prostate biopsies. Thus, emphasis has been placed on identifying new biomarkers to improve prostate cancer detection. Glypican-1 has recently been proposed as one such biomarker, however further exploration into its predictive power has been hindered by a lack of available, dependable glypican-1 immunoassays. Previously, we identified human glypican-1 as the antigenic target of the MIL-38 monoclonal antibody. Additionally, we have now generated another monoclonal antibody, 3G5, that also recognizes human glypican-1. Here we report the development of a reliable, custom Luminex® assay that enables precise quantitation of circulating human glypican-1 in plasma and serum. Using this assay, we show for the first time that circulating glypican-1 levels can differentiate non-cancer (normal and benign prostatic hyperplasia) patients from prostate cancer patients, as well as benign prostatic hyperplasia patients alone from prostate cancer patients. Our findings strongly promote future investigation into the use of glypican-1 for early detection of prostate cancer.

Abstract A20: A phase II randomized, presurgical placebo-controlled trial of polyphenon E in bladder cancer patients to evaluate bladder tissue levels of EGCG and biomarkers of growth and apoptosis

Introduction: Bladder cancer patients are faced with significant morbidity and mortality due to tumor recurrence and progression and therefore would benefit from an effective chemopreventive strategy. Green tea consumption has been associated with a reduction in bladder cancer risk. Polyphenon E is a green tea polyphenol formulation primarily consisting of epigallocatechin gallate (EGCG) which has been shown in preclinical studies to inhibit growth of bladder cancer. We evaluated the tolerability, tissue accumulation, and biologic effects of polyphenon E in a randomized, double-blind, placebo-controlled phase II preoperative study in patients with bladder cancer. Methods: Patients who had an initial diagnosis or recurring bladder tumor found on diagnostic cystoscopy were randomized in a 1:1:1 ratio to receive 800 mg, 1200 mg or placebo polyphenon E prior to undergoing TURBT or radical cystectomy. The primary objective of the study was to assess the nonmalignant bladder tissue levels of EGCG. Secondary objectives included comparison of EGCG levels in nonmalignant versus malignant tissue within treatment arms; examination of the dose-dependent modulation of surrogate endpoint biomarkers (PCNA, MMP2, Clusterin, VEGF, p27, IGF-1, IGFBP-3) in malignant and nonmalignant bladder tissue; correlation of plasma, urine and tissue levels of EGCG; examination of the levels of other catechins (epicatechin, epicatechin gallate, and epigallocatechin) in plasma, tissue, and urine; metabolism of EGCG in plasma, urine and tissue by COMT and UGT in relation to pharmacogenomic mutations. Results: 31 patients (84% male, 16% female) were randomized with a mean age of 67.2 years. Four patients (13%) were non-compliant and drug administration was interrupted in one other patient (3%), whereas the remainder of patients for which we have reports completed study agent administration (n=24, 77%). The worst adverse event severity was severe (grade 3) for one (3%) patient, moderate for five patients (16%), and mild for eight (26%) patients, whereas no adverse event occurred in 17 (55%) of the patients. Although we found a low rate of detectability in tissue (4/25 with detectable values), tissue levels of EGCG were identified in a dose-dependent fashion in both normal (0.00, 0.50, 1.72 ng/ml, p=0.046) and malignant (0.00, 0.00, 2.54 ng/ml p=0.005) bladder tissue for the placebo, low dose and high dose polyphenon E arms respectively. Plasma EGCG levels (2.94, 78.09, 87.52 ng/ml, p=0.001) and urine EGCG levels (0.00, 2.60, 4.32 ng/ml, p Conclusions: We demonstrate in a phase II pilot study tissue accumulation of EGCG in benign and malignant bladder urothelium which follows both plasma and urine levels in a dose-dependent fashion. Furthermore, tissue endpoint biomarkers of proliferation (PCNA) and apoptosis (clusterin) were reduced in a statistically significant dose-dependent fashion. Acknowledging the limitations of this pilot study, we feel these findings indicate polyphenon E administration results in definable tissue accumulation and more importantly desirable biologic activity which warrant further clinical studies assessing the effect of polyphenon E on actual bladder tumor recurrence/progression. Citation Format: Jason R. Gee, Daniel R. Saltzstein, KyungMann Kim, Jill Kolesar, Wei Huang, Tom Havighurst, Barbara W. Wollmer, Jeanne Stublaski, Tracy Downs, Hasan Mukhtar, Margaret House, Howard Parnes, Howard Bailey. A phase II randomized, presurgical placebo-controlled trial of polyphenon E in bladder cancer patients to evaluate bladder tissue levels of EGCG and biomarkers of growth and apoptosis. [abstract]. In: Proceedings of the Thirteenth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2014 Sep 27-Oct 1; New Orleans, LA. Philadelphia (PA): AACR; Can Prev Res 2015;8(10 Suppl): Abstract nr A20.