Closed due to low accrual

RATIONALE: Genistein may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.

PURPOSE: This randomized phase II trial is studying how well genistein works in treating patients with prostate cancer.

PRIMARY OBJECTIVES:

I. Determine whether genistein treatment will decrease the number of circulating prostate cells (CPCs) in the peripheral blood as measured by qRT-PCR for PSA performed on RNA extracted from peripheral blood mononuclear cells (PBMNCs).

SECONDARY OBJECTIVES:

I. Determine the natural history of circulating prostate cells (CPCs) in a cohort of subjects prior to and post radical prostatectomy.

II. Compare the measurement of PSA between three separate methods: in CPCs by qRT-PCR, in serum by the standard clinical chemistry assay (i.e., ELISA), and in plasma and serum by the nano-PSA assay.

III. Measure the effect of genistein on gene and protein expression in prostate tissue by qRT-PCR and immunohistochemistry, respectively, for the following genes and their respective protein products: HSP27, MMP-2, ALK-2, BASP1, and HCF2.

OUTLINE:

Patients are randomized to 1 of 2 treatment arms.

ARM I: Patients receive oral genistein once daily for 3 months beginning at least 1 month prior to radical prostatectomy.

ARM II: Patients receive oral placebo once daily for 3 months beginning at least 1 month prior to radical prostatectomy.

All patients undergo radical prostatectomy at least 2 weeks, but not more than 3 months following the start of therapy.

After completion of study treatment, patients are followed at 1, 6, and 12 months.

Inclusion

• Participants must have a pathologic diagnosis of prostate cancer within the past 6 months, have clinical stage T1-3 disease, PSA >= 10, Gleason score >= 8, and have elected to undergo radical prostatectomy; those found to have detectable circulating prostate cancer cells in the blood as detected by qRT-PCR for PSA will be eligible to proceed onto the treatment phase of the protocol; pathology slides used for diagnosis will be submitted to the SPORE tissue pathology core for review
• ECOG performance status 0-1
• Hemoglobin > 9.0gm/dl
• Platelets >= 100 K/uL
• ANC > 1000/uL
• AST (SGOT)/ALT (SGPT) < 3X upper limit of normal
• Creatinine < 2.0 mg/dl
• Total bilirubin < 2 mg/dl (Note: Subjects with a higher level of bilirubin due to a familial defect in bilirubin metabolism will be considered on an individual basis)
• Participants must agree not to take soy supplements
• Ability to understand and the willingness to sign a written informed consent document
• Willingness to take study agent for at least 2 weeks prior to radical prostatectomy

Exclusion

• History of venous thrombosis within past year
• Participants must not be receiving active therapy for neoplastic disorders (including hormone or radiation therapy for prostate cancer)
• Participants may not be receiving any other investigational agents
• Known soy intolerance
• Medical conditions that, in the opinion of the investigators, would jeopardize either the patient or the integrity of the data obtained

Adverse Events assessed at the following timepoints for the study: at the start of treatment, at surgery or radiation, at clinic visits occurring 1-3 months post-surgery, or post-initiation of radiation therapy, or at 3 months for those not undergoing surgery or radiation, as well as at a 4 month telephone contact.

Adverse events were collected by patient reports

The study was closed by an internal safety and data monitoring committee due to slow accrual of the study.