Evaluation of biodistribution of sulforaphane after administration of oral broccoli sprout extract in melanoma patients with multiple atypical nevi.
Cancer Prev Res (Phila). 2018 Apr 24. Epub 2018 Apr 24. PMID: 29691233
Broccoli sprout extract containing sulforaphane (BSE-SFN) has been shown to inhibit ultraviolet radiation-induced damage and tumor progression in skin. This study evaluated the toxicity and potential effects of oral BSE-SFN at three dosages. Seventeen patients who each had at least 2 atypical nevi and a prior history of melanoma were randomly allocated to 50, 100, or 200µmol oral BSE-SFN daily for 28 days. Atypical nevi were photographed on days 1 and 28, and plasma and nevus samples were taken on days 1, 2, and 28. Endpoints assessed were safety, plasma and skin sulforaphane levels, gross and histologic changes, immunohistochemistry for phospho-STAT3(Y705), Ki-67, Bcl-2, HMOX1, and TUNEL, plasma cytokine levels, and tissue proteomics. All 17 patients completed 28 days with no dose-limiting toxicities. Plasma sulforaphane levels pooled for days 1, 2, and 28 showed median post-administration increases of 120 ng/mL for 50 µmol, 206 ng/mL for 100 µmol, and 655 ng/mL for 200 µmol. Median skin sulforaphane levels on day 28 were 0.0 ng/g, 3.1 ng/g, and 34.1 ng/g for 50, 100, and 200 µmol, respectively. Plasma levels of pro-inflammatory cytokines decreased from day 1 to 28. The tumor suppressor decorin was increased from day 1 to 28. Oral BSE-SFN is well-tolerated at daily doses up to 200 µmol and achieves dose-dependent levels in plasma and skin. A larger efficacy evaluation of 200 µmol daily for longer intervals is now reasonable to better characterize clinical and biological effects of BSE-SFN as chemoprevention for melanoma.