A diet that mimics fasting combined with hormone therapy has the potential to help treat breast cancer, according to a new study by USC-led team of international scientists.
In studies on mice and in two small breast cancer clinical trials, researchers at the University of Southern California and the IFOM Cancer Institute in Milan — in collaboration with the University of Genova — found that the fasting-mimicking diet reduces blood insulin, insulin-like growth factor 1 (IGF1) and leptin.
In mice, these effects appear to increase the power of the cancer hormone drugs fulvestrant and tamoxifen and delay any resistance to them. The results from around three dozen women treated with the hormone therapy and fasting-mimicking diet are promising, but scientists feel it is still too early to determine whether the effects will be confirmed in large-scale clinical trials.
The research was published in the journal Nature.
“Our new study suggests that a fasting-mimicking diet together with endocrine therapy for breast cancer has the potential to not only shrink tumors but also reverse resistant tumors in mice,” said Valter Longo, the study’s co-senior author and the director of the Longevity Institute at the USC Leonard Davis School of Gerontology and professor of biological sciences at the USC Dornsife College of Letters, Arts and Sciences.
“We have data that for the first time suggests that a fasting-mimicking diet works by changing at least three different factors: IGF1, leptin and insulin,” Longo added.
The researchers say the two small clinical trials showed promising results, but it is difficult to say that they are conclusive. They believe the results support further clinical studies of a fasting-mimicking diet used in combination with endocrine therapy in hormone-receptor-positive breast cancer.
The scientists also contributed to a recent clinical study of 129 breast cancer patients conducted with the University of Leiden.
