Inclusion Criteria:

- All patients, 18 of age or older, with hormone refractory prostate cancer are
eligible.

- Patients must have a life expectancy of at least 12 weeks.

- Patients must have a Zubrod performance status of 0-2.

- Patients must sign an informed consent.

- Patients should have adequate bone marrow function defined by an absolute peripheral
granulocyte count of > 1,500 or cells/mm3 and platelet count >100,000/mm3 and absence
of a regular red blood cell transfusion requirement.

- Patients should have adequate hepatic function with a total bilirubin < 2 mg/dl and
SGOT or SGPT < two times the upper limit of normal, and adequate renal function as
defined by a serum creatinine < 1.5 x upper limit of normal.

- Patients must have pathologically confirmed prostate cancer with PSA increasing
despite androgen deprivation therapy.

- Diabetic patients on therapy with Metformin are eligible provided that their
Metformin dose is at least 850mg twice daily.

Exclusion Criteria:

- Patients with symptomatic brain metastases are excluded from this study.

- Patients on insulin are not eligible.

- Patients may receive no other concurrent chemotherapy or radiation therapy during
this trial.

- Patients with severe medical problems such as uncontrolled diabetes mellitus,
cardiovascular disease, and congestive heart failure defined as New York Heart
Association Class III or IV, hepatic dysfunction, or active infections are not
eligible for this trial.