Soybean isoflavones reduce experimental metastasis in mice

Area of Science:

• Oncology
• Nutrition Science
• Pharmacology

Background:

• Melanoma is a significant form of skin cancer with a high potential for metastasis.
• Pulmonary metastasis is a common and often fatal complication of melanoma.
• Isoflavones, found in soy products, have demonstrated anti-cancer properties in preclinical studies.

Purpose of the Study:

• To investigate the effect of dietary isoflavone supplementation on experimental pulmonary metastasis of murine melanoma cells.
• To determine the dose-dependent efficacy of genistein and daidzein in inhibiting melanoma cell metastasis in vivo.

Main Methods:

• C57BL/6 mice were fed a standard diet or a diet supplemented with varying concentrations of genistein and daidzein (113-900 micromol/kg).
• Mice received intravenous injections of B16BL6 murine melanoma cells.
• Tumor burden, including the number and size of lung metastases, was assessed at necropsy.

Main Results:

• Dietary isoflavone supplementation significantly reduced the number of lung tumors, particularly at higher doses (450 and 900 micromol/kg).
• A significant decrease in the median number of tumors was observed in mice receiving 900 micromol/kg of isoflavones compared to controls.
• Isoflavone intake at 225, 450, and 900 micromol/kg also led to a significant reduction in tumor size.

Conclusions:

• Dietary supplementation with isoflavones effectively reduces experimental pulmonary metastasis of melanoma cells in a murine model.
• Genistein and daidzein show promise as dietary agents for inhibiting melanoma spread.
• These findings support further research into isoflavones as a complementary approach in melanoma treatment.