Image
© n/aMustard Seeds
Mustard seed powder stops bladder cancer cell growth and invasion of surrounding tissues in rats.

A study with rats finds a plant compound abundant in mustard, horseradish and wasabi stopped the growth of bladder cancer by one-third and completely prevented metastasis - the cancer invasion of surrounding muscle tissue. Additionally, the food tested - in this case, a mustard seed powder that naturally contains the allyl isothiocyanate (AITC) compound - was more effective at controlling the cancer than the purified form.

These animal findings show - at least in this case - that bladder tumors can be kept from spreading outside of the bladder. These new findings bolster others that show mustard seed has anti-cancer properties and support a rich history of its use in traditional Chinese and folk medicines. The authors suggest that further clinical "evaluation of this substance is warranted."

In people, bladder cancers are typically not life threatening unless they invade the surrounding muscles. This occurs in 15-30 percent of bladder cancer patients. The patients then require aggressive therapy, including bladder removal. Even then, survival rates are low.

Besides mustard, many other edibles from the cabbage family - known as cruciferous vegetables - contain AITC. Other relatives - such as cauliflower, broccoli and kale - are also known to lower overall cancer risk and supply important vitamins.

In tests using human cells, AITC selectively kills bladder cancer cells but leaves healthy bladder cells unharmed. When vegetables high in AITC are consumed, the AITC is mainly excreted in the urine, where it ends up in the bladder and works to prevent cancer.

Dry mustard seeds contain a highly stable compound similar to AITC called sinigrin. When water is added - as happens when the seeds are eaten - a seed-based enzyme converts the sinigrin to AITC. The human digestive tract has a related form of this enzyme but the plant-derived version is much more effective.

For this study, researchers fed mustard seed powder (71.5 or 715 mg/kg body weight) mixed with about 0.5 milliliters of water once a day to female rats in the earliest stage of bladder cancer. Treatment continued for three weeks. After that, the bladders were examined for cancer. Treated animals were compared to control animals that received only water. To test the effect on human cancer, they also treated human and rat bladder cancer cells with the mustard seed.

Bladder tumors grow extremely fast. After three weeks, cancerous bladders in the untreated control animals weighed five times more than disease-free bladders. The tumors had invaded the surrounding muscle tissue 71 percent of the time.

In animals treated with the lower dose of mustard seed powder, tumor weights were 35 percent smaller, on average, with no muscle invasion. Interestingly, rats fed the higher dose, had a smaller decline - only 23 percent lower - in tumor growth, and the tumors invaded the surrounding muscle at a higher rate - up to 62 percent. The findings show the lower dose was much more effective at preventing bladder cancer progression and invasion.

The mustard seed also killed the human cancer cells when treated in the laboratory.

The authors note that the amount of AITC stored in mustard seed powder differs substantially depending on the species and the commercial preparation method. The authors screened four mustard seed preparations from four different vendors before choosing the one with the highest activity.

Reference

Bhattacharya, A, Y Li, KL Wade, JD Paonessa, JW Fahey and Y Zhang. 2010. Allyl isothiocyanate-rich mustard seed powder inhibits bladder cancer growth and muscle invasion. Carcinogenesis.