• by: Valter Longo Foundation Editorial Staff
  • June 9th, 2020

The research team led by Prof. Valter Longo has identified a new therapeutic approach, which combines a low-calorie diet that simulates fasting (Fasting Mimicking Diet) and pharmacological doses of vitamin C, to be combined with chemotherapy, able to particularly target cancer cells mutated in the KRAS oncogene.

The research was conducted by the team of researchers from the Longevity and Cancer laboratory of the IFOM in Milan and the Longevity Institute of the University of Southern California led by Valter Longo, thanks to the support of AIRC (Italian Association for Cancer Research) . The study, published in the scientific journal “Nature Communications” of which Maira Di Tano is the first author, proposes a new effective and low toxicity approach for the treatment of more aggressive tumors and highly resistant to conventional therapies, such as those characterized by mutations in KRAS. The study combines for the first time two non-toxic treatments that can be combined with current chemotherapies: Fasting Mimicking Diet cycles and pharmacological doses of vitamin C.

What are the known effects of the Fasting Mimicking Diet on tumors?

In recent years, the research team led by Prof. Valter Longo has shown in several studies that cycles of a Fasting Mimicking Diet, in addition to decreasing some risk factors for diseases (hyperglycemia, high cholesterol, high inflammation, etc.), are also able to slow down tumor growth in pre-clinical animal models of different types of cancer, enhance the effectiveness of chemotherapy and, at the same time, protect healthy tissues from the side effects that it entails. Several clinical trials are currently underway on cancer patients with different types of cancer.

What is the role of vitamin C in cancer treatment?

It is important to remember that the use of vitamin C as an anticancer agent is widely fought and a clarification must be made. By now, many studies have shown an anti-tumor effect of pharmacological doses of vitamin C, albeit limited, in pre-clinical models. When we refer to pharmacological doses, we mean “mega-doses” that cannot be achieved with the simple oral administration of supplements or through our diet. To achieve these doses, vitamin C must be administered intravenously directly into the bloodstream. By now, what many studies have clearly shown is that high-doses of vitamin C, through various chemical reactions, produces a massive amount of oxidizing agents and free radicals capable of damaging the DNA of cancer cells and leading them to die. Normal cells, on the other hand, are able to defend themselves thanks to their systems of protection and repair from oxidative stress, thus leaving healthy tissues safe by the action of vitamin C. At the moment, several clinical studies are underway to understand its effectiveness in cancer patients.

How is the Fasting-Mimicking Diet capable of potentiating the anti-tumor effects of vitamin C?

Previous studies conducted by Prof. Longo had already shown how the Fasting-Mimicking Diet was able to increase oxidative stress only in cancer cells, while protecting normal ones. Based on these data, we asked ourselves if the Fasting-Mimicking Diet could therefore increase the oxidative damage generated by high doses of vitamin C and by which mechanisms.

We have found that cancer cells mutated in the KRAS oncogene try to protect themselves from oxidative stress induced by vitamin C, by increasing the expression of an enzyme capable of limiting the levels of free iron: heme oxygenase-1 (HO- 1). The Fasting-Mimicking Diet prevents the activation of this defense mechanism in cancer cells, thus making them more vulnerable and much more sensitive to treatment.

On which types of cancer has the treatment proved effective?

The research focused mainly on colon cancer, a neoplasm that affects around 49,000 people a year in Italy and which is frequently associated with mutations in the KRAS oncogene.

In several cell models in vitro and in laboratory animals, treatment with pharmacological doses of vitamin C and cycles of the Fasting-Mimicking Diet has proven effective in slowing tumor growth until it completely regresses the tumor in some mice. The most important data was obtained when the Fasting Mimicking Dietand vitamin C were combined with chemotherapy, in fact this combination proved to be the most effective in prolonging the survival of laboratory animals.

However, we have also obtained promising data in cellular studies of other cancers that often present mutations in KRAS such as lung and pancreatic cancer.

What consequences do you think your discovery will have for cancer therapy?

Certainly many studies are still needed. We obtained promising data both in cellular models and in pre-clinical studies in mice. Our goal is to be able to give an effective and low toxicity therapeutic option to cancer patients. KRAS mutated tumors are highly aggressive and resistant to standard therapies, so I believe that our discovery can have an important impact on the treatment of these tumors while safeguarding the quality of life of the patient.



By Fondazione Valter Longo Onlus editorial staff
Fondazione Valter Longo Onlus aims to make scientific dissemination by raising awareness among the scientific and non-scientific community of a healthy lifestyle and proper nutrition through the production of explanatory scientific articles, textual, infographics and multimedia content, and the dissemination of clinical activities scientific, informative and educational aspects of the Foundation and its team of professionals. Dietary pathways, scientific discoveries, clinical studies, treatments and technologies, national and international awareness events, prevention initiatives as well as Longevity recipes are just some of the topics addressed in articles and in-depth interviews published daily and written in collaboration with the Foundation’s specialists. Also active on social networks, Fondazione Valter Longo Onlus editorial staff also offers a monthly newsletter sent to all members, to stay up to date on the most interesting news related to the world of Health, Nutrition and Longevity.
Romina Inés Cervigni
Alessandra Fedato
Maria Liliana Ciraulo
Corinna Montana Lampo
Cristina Villa
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