Patients must be off prior chemotherapy, hormonal therapy, radiation therapy, or biological therapy for at least 4 weeks prior to initiation of COL-3. Patients who were receiving mitomycin C, nitrosoureas, or carboplatin must be 6 weeks from the last administration of chemotherapy. Patients who were receiving suramin must be 3 months from the last administration. Patients with prostate cancer must continue to receive LHRH agonist (unless orchiectomy has been done) but must have failed antiandrogen withdrawal.