Prostate cancer comes in various forms and has proven difficult to treat. Provided herein are various methods and compositions for treating all forms of prostate cancers with dopa decarboxylase (DDC) inhibitors. These dopa decarboxylase inhibitors include carbidopa (α-Methyl-dopahydrazine), MFMD (α-monofluoromethyldopa), NSD-1015 (3-hydroxybenzylhydrazine), Methyldopa (L-α-Methyl-3,4-dihydroxyphenylalanine) or benserazide, and the inhibitors may be used in combination. DDC inhibitors may also be used to inhibit the progression of prostate cancer to androgen-independence and neuroendocrine prostate cancer.
