Docetaxel (Taxotere) and Imatinib Mesylate (Gleevec) in Hormone Refractory Prostate Cancer

Inclusion Criteria: * Patients at least 18 years of age. * Histologically documented diagnosis of adenocarcinoma of prostate gland * Patients must have hormone refractory prostate cancer having progressed after at least two prior hormonal manipulations with documented castrate levels of testosterone (\<50 ng/dl). PSA ≥ 5 ng/ml * Patients must have hormone-refractory prostate carcinoma as evidenced by PSA progression, with or without evidence of measurable disease, or evaluable disease by a positive bone scan. PSA progression is defined as \> 25% increase in 2 consecutive tests in which the first increase in PSA should occur a minimum of 1 week from the reference value and this increase in PSA should be confirmed and ≥ 5 ng/ml * Eligible patients will have been treated with at least two prior hormonal manipulations including androgen deprivation and may have received one prior chemotherapy regimen. * Any chemotherapy, major surgery, or irradiation must have been completed at least 3 weeks prior to starting study drugs. Patient must have recovered from clinically significant toxicities incurred as a result of previous therapy except nail dystrophy, alopecia, grade 1 peripheral neuropathy, or radiation therapy induced affects (i.e., impotence or incontinence) * No recent prior flutamide (Eulexin) use within the past 4 weeks, prior bicalutamide (Casodex) use within the past 6 weeks, or prior nilutamide (Nilandron) use within the past 6 weeks. * Performance status 0,1, 2 (Eastern Cooperative Oncology Group performance status scale) * Adequate end organ function, defined as the following: * total bilirubin \< 1.5 x upper limit of Normal (ULN) * Serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) \< 2.5 x ULN * creatinine \< 1.5 x ULN * Absolute Neutrophil count (ANC) \> 1.5 x 10\^9/L * platelets \> 100 x 10\^9/L * Written, voluntary informed consent. * Patients must have been and continue to be on androgen deprivation therapy with a Luteinizing hormone-releasing hormone (LHRH) agonist or antagonist during study participation except for patients who had orchiectomy. * Patients on secondary hormonal manipulation with ketoconazole and hydrocortisone who discontinued LHRH therapy must be switched to single agent LHRH analogue therapy unless they had orchiectomy. * Patients being treated with Zometa prior to the initiation of the study will be permitted to continue with Zometa while on the study. Exclusion Criteria: * Patient has received any other investigational agents within 28 days of first day of study drug dosing, unless the disease is rapidly progressing. * Patient is \< 5 years free of another primary malignancy except: if the other primary malignancy is not currently clinically significant nor requiring active intervention, or if other primary malignancy is a basal cell skin cancer or a cervical carcinoma in situ. Existence of any other malignant disease is not allowed. * Patient with Grade III/IV cardiac problems as defined by the New York Heart Association Criteria. (i.e., congestive heart failure, myocardial infarction within 6 months of study) * Patient has a severe and/or uncontrolled medical disease (i.e., uncontrolled diabetes, chronic renal disease, or active uncontrolled infection). * Patient with untreated brain metastasis or cord compression. However, patients with treated spinal cord compression or central nervous system (CNS) metastases that have been stable are eligible. * Patient has known chronic liver disease (i.e., chronic active hepatitis, and cirrhosis). * Patient has a known diagnosis of human immunodeficiency virus (HIV) infection. * Patient received chemotherapy within 4 weeks (6 weeks for nitrosourea or mitomycin-C) prior to study entry, unless the disease is rapidly progressing. * Patient previously received radiotherapy to at least 25 % of the bone marrow * Patient had a major surgery within 2 weeks prior to study entry. * Patient with any significant history of non-compliance to medical regimens or with inability to grant reliable informed consent. * If the patient is taking steroids for prostate cancer, then the patient is ineligible for this study. If the patient is taking steroids for conditions other than prostate cancer, the patient is eligible provided that the reasons for use and dosage are documented. The investigator is urged to discuss this issue with the Study Principal Investigator for any clarification. * No therapeutic anticoagulation with warfarin (e.g. Coumadin® or Coumadine®) will be permitted in patients participating in this study.