June 12, 2006

Sulforaphane helps block metastasis

A report published in the May 22, 2006 issue of the journal Life Sciences revealed the findings of P. Thejass and Girija Kuttan at the Amala Cancer Research Center in Kerala, India that sulforaphane significantly prevented the metastasis of melanoma cells in mice. Sulforaphane is an isothiocyanate found in broccoli and other cruciferous vegetables that has been shown to help protect against chemically-induced tumors.

The current study utilized mice in whom melanoma tumor cells were injected. Five hundred micrograms per kilogram body weight sulforaphane was administered to one group of mice at the same time as the tumor cells were injected, while two other groups received the compound 10 days prior to and 10 days after the cells were injected. A control group of animals injected with tumor cells received no sulforaphane.

The control mice were found to have a significant amount of lung tumors compared to animals who received sulforaphane. Sulforaphane given simultaneously with the tumor cells was the most effective mode of administration, being associated with an inhibition of 95.5 percent of metastases, and an increase in lifespan of 94 percent compared to the control group. Preventive administration was the second most effective mode, which inhibited metastases by 90.51 percent and increased the lifespan of this group by 62.17. Giving sulforaphane after the tumors had developed increased lifespan by 37.85 compared to animals who did not receive the compound. In addition, sulforaphane was associated with a reduction in levels of lung tumor-associated compounds, such as lung hydroxyproline.

In-vitro research showed that sulforaphane inhibited the activation of matrix metalloproteinases, which are enzymes that degrade the cell membrane and facilitate the metastasis of tumors. The authors suggest that sulforaphane's antimetastatic activity may be mainly due to this action.