Can anti-ageing supplements fuel cancer? Here's what a new study finds

A new study reveals how polyamines such as spermidine alter protein synthesis in cancer cells, separating their healthy ageing effects from their tumour-promoting potential

New research suggests that a substance found in everyday foods and longevity supplements may help cancer cells thrive, under certain conditions.

 

The study titled Polyamines stimulate the protein synthesis of the translation initiation factor eIF5A2, participating in mRNA decoding, distinct from eIF5A1, published in the Journal of Biological Chemistry, found that polyamines, which are natural molecules found in our cells and widely marketed in anti-ageing supplements such as spermidine, can boost production of a cancer-linked protein called eIF5A2. This cancer-driving process operates separately from the pathway tied to their healthy ageing benefits, say researchers at Tokyo University of Science.

What are polyamines, and why are they popular in anti-ageing circles?

According to the study, polyamines, including putrescine, spermidine, and spermine, are positively charged molecules present in every living cell. They are essential for cell growth, division, and function.

 

Spermidine occurs naturally in foods such as wheat germ, mushrooms, soybeans and aged cheese. It is also sold as a dietary supplement. Previous research has shown that spermidine can trigger autophagy, the cell’s internal “clean-up” process. Autophagy helps remove damaged components inside cells and is linked to healthier ageing and better mitochondrial function.

 

Much of this benefit is thought to involve a protein called eIF5A1, which supports protein production and mitochondrial activity in healthy cells.

Why are scientists concerned about cancer risk?

Higher levels of polyamines are often found in many types of cancer. Tumours rely on rapid growth, and polyamines naturally support cell growth.

 

Cancer cells also depend heavily on a fast energy-producing process called aerobic glycolysis. This means they convert glucose into energy quickly, even when oxygen is present. This shortcut helps them multiply rapidly.

 

Until now, scientists had not clearly understood how polyamines influence cancer cell metabolism and protein production at the molecular level. 

What did the new study discover about polyamines?

The team carried out experiments in human cancer cell lines. They first reduced polyamine levels using a drug and then restored them using spermidine. They examined changes in more than 6,700 proteins.

 

They found that polyamines did not significantly change gene activity at the mRNA level. Instead, they acted at the stage where cells actually make proteins from genetic instructions. In simple terms, polyamines changed which proteins were produced, rather than which genes were turned on.

 

Most notably, polyamines strongly increased production of eIF5A2, a protein closely linked to cancer progression.

 

At the same time, polyamines boosted glycolysis, which is the energy pathway preferred by cancer cells rather than mitochondrial respiration, which is more closely associated with healthy ageing.

What is the difference between eIF5A1 and eIF5A2?

Humans have two closely related proteins: eIF5A1 and eIF5A2. They are 84 per cent similar in structure. For years, researchers mainly studied eIF5A1 because it is found in most normal tissues and is essential for healthy cell growth. eIF5A2, however, is often overproduced in cancer tissues.

 

The study shows that polyamines increase eIF5A2 production at the protein-making stage. When researchers switched off eIF5A2, cancer cell growth slowed significantly. Switching off eIF5A1 did not have the same strong effect.

 

The researchers also found that under normal conditions, a small regulatory molecule called miR-6514-5p keeps eIF5A2 levels in check. Polyamines interfere with this control, allowing more eIF5A2 protein to be produced.

Do spermidine supplements cause cancer?

The researchers stress that their experiments were conducted in cancer cell lines, not in healthy humans taking dietary supplements. It does not prove that spermidine supplements cause cancer.

 

In normal tissues, polyamines may promote healthy ageing via eIF5A1 and autophagy. In malignant or pre-malignant tissues, the same molecules may stimulate eIF5A2 and glycolysis, potentially accelerating tumour growth.

What are the implications for cancer therapy and supplements?

The findings identify eIF5A2 and its interaction with ribosomes as a potential selective target for cancer treatment. If researchers can block the polyamine–eIF5A2 pathway without disrupting the beneficial eIF5A1 pathway, it may be possible to design therapies that curb tumour growth while preserving normal cellular function.