Do Antioxidants Prevent Cancer from Spreading?

While antioxidants are associated with boosting the immune system and supporting overall health, new research published online in the journal Cell suggests that the supplements could fast-track the spread of lung cancer. The findings challenge previous research hailing antioxidants such as Vitamin E for their cancer preventing properties. Instead, the study warns there could be a link between antioxidants and common mutations found in lung cancer cells.

Antioxidants support invasion of chest cavity tissues

Led by cancer biologist Michele Pagano, the study saw antioxidants administered to both humans and mice. The team noted an increase in oxidation-inhibiting compounds that aid lung cancer cells in invading chest cavity tissues. Furthermore, the antioxidants actively protected tumours against damage from molecules designed to attack cancerous cells. The team also recorded an increase in build-up of Bach1, a protein that can accumulate in the body and help tumours rapidly burn through glucose and migrate to new organs.

“The results provide a new mechanism for how lung cancer cells can spread and may lead to new possibilities for treatment,” explains study co-author Martin Bergo, a molecular biologist at the Karolinska Institutet in Stockholm.

New research could help combat lung cancer fatalities

Claiming around 1.6 million lives a year, lung cancer is the world's leading cause of cancer-related deaths. Most fatalities are powered by metastasis, a process that sees cancer cells split from the original tumour and infiltrate the bloodstream or lymphatic system, which spreads the disease around the body.

The study sought to explore the connection between antioxidants and common mutations found in lung cancer cells, with Pagano and his team discovering that antioxidants actively neutralise free radicals and allow the destructive molecules to accumulate during the cell metabolism process. The theory that antioxidants support the spread of cancer is backed by additional findings revealing that around 30% of Non-small-cell lung carcinoma (NSCLC) tumours develop mutations caused by one of two major genes associated with the production and regulation of natural antioxidants.

Pagano explains that the genetic mutations can either increase production or prevent the destruction of Nrf2, a protein that activates genes responsible for producing antioxidants. This allows tumours to defend themselves against free radicals released during growth and instead, spread to other areas of the body.

Antioxidants block cancer defence systems

Furthermore, the study notes that oxidative stress and the release of free radicals usually correlates with the release of damaging free-floating heme pigments. In response, healthy cells produce an enzyme known as heme oxygenase-1 or Ho1 to destroy excess heme. However, in cancerous cells this response is blocked and as a result, high levels of antioxidants and Nrf2 support the production of Ho1 and activate the gene mutations that drive metastasis.        

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