An enzyme commonly used as a target for antidepressants may also promote prostate cancer growth, an international team of scientists report. The study found that suppressing the enzyme monoamine oxidase A, or MAOA, may reduce or even eliminate prostate tumor growth and metastasis in laboratory mice. The finding could open the door for physicians to use antidepressants to fight prostate cancer. Currently, drugs that inhibit MAOA enzymes are used to treat patients with mental illnesses like depression.