Assess Gamma H2AX Positivity in Circulating Prostate Cancer Cells Before and After Radium 223

Inclusion Criteria:

Male patients 18 years or older
Histologically or cytologically confirmed adenocarcinoma of the prostate
Receiving radium 223 as standard of care for symptomatic metastatic castration resistant prostate cancer to the bone as documented by bone scan or Sodium Fluoride positron emission tomography (PET) bone scan.
No evidence of visceral metastasis
Prior surgical castration or concurrent use of GnRH analogue (i.e., medical castration) with testosterone at screening <50 ng/dL.
Eastern Cooperative Oncology Group (ECOG) performance status 0 -2, ECOG 3 is allowed if due to pain
Adequate organ function: Serum alanine aminotransferase (ALT) or aspirate aminotransferase (AST) must be < 2.5 x upper limit of normal (ULN); Total bilirubin < 1.5 s ULN; Estimated creatinine clearance must be >40 mL/min; Absolute neutrophil count (ANC) > 1500/l; Hemoglobin above 10 g/dl; platelet count > 100,000/l.
Stable medical condition, including the absence of acute exacerbations of chronic illnesses, serious infections or major surgery within 28 days prior to study enrollment
Life expectancy of 6 months or more
Must agree to practice effective barrier contraception during the entire study treatment period & through for 6 months after the last dose of study drug, or agree to completely abstain from heterosexual intercourse
Able to give written informed consent
Have at least 2 CTCs at baseline

Exclusion Criteria:

Exposure to radioisotope therapy (samarium 153, strontium 89) within 24 weeks or exposure to external beam radiation within 12 weeks of receiving the first dose of Radium 223
Documented central nervous system metastases, has a history of seizure, stroke or transient ischemic attack (TIA)
Treatment with any investigational compound within 30 days prior to the first dose of study drugs
Diagnosis or treatment for another systemic malignancy within 2 years before the first dose of study drugs, or previously diagnosed with another malignancy & have any evidence of residual disease. Patients with non-melanoma skin cancer or carcinoma in situ of any type are not excluded if they have undergone complete resection.
New York Association Class III or IV heart failure
Known human immunodeficiency virus (HIV) infection, active chronic hepatitis B or C, life threatening illness unrelated to cancer, or any serious medical or psychiatric illness that could, in investigators opinion, potentially interfere with participation in this study.
Potential participants with delayed healing of wounds, ulcers, and/or bone fractures
Inability to comply with protocol requirements