Date:

October 13, 2017

Source:

VIB

Summary:

A nine-year joint research project has led
to a crucial breakthrough in cancer research. Scientists have clarified how the
Warburg effect, a phenomenon in which cancer cells rapidly break down sugars,
stimulates tumor growth. This discovery provides evidence for a positive
correlation between sugar and cancer, which may have far-reaching impacts on
tailor-made diets for cancer patients.

A nine-year joint
research project conducted by VIB, KU Leuven and VUB has led to a crucial
breakthrough in cancer research. Scientists have clarified how the Warburg
effect, a phenomenon in which cancer cells rapidly break down sugars,
stimulates tumor growth. This discovery provides evidence for a positive
correlation between sugar and cancer, which may have far-reaching impacts on
tailor-made diets for cancer patients. The research has been published in the
leading academic journal Nature Communications.

This project was started
in 2008 under the leadership of Johan Thevelein (VIB-KU Leuven), Wim Versées
(VIB-VUB) and Veerle Janssens (KU Leuven). Its main focus was the Warburg
effect, or the observation that tumors convert significantly higher amounts of
sugar into lactate compared to healthy tissues. As one of the most prominent
features of cancer cells, this phenomenon has been extensively studied and even
used to detect brain tumors, among other applications. But thus far, it has
been unclear whether the effect is merely a symptom of cancer, or a cause.

Sugar awakens cancer
cells

While earlier research
into cancer cell metabolism focused on mapping out metabolic peculiarities,
this study clarifies the link between metabolic deviation and oncogenic potency
in cancerous cells.

Prof. Johan Thevelein
(VIB-KU Leuven): “Our research reveals how the hyperactive sugar
consumption of cancerous cells leads to a vicious cycle of continued stimulation
of cancer development and growth. Thus, it is able to explain the correlation
between the strength of the Warburg effect and tumor aggressiveness. This link
between sugar and cancer has sweeping consequences. Our results provide a
foundation for future research in this domain, which can now be performed with
a much more precise and relevant focus.”

Yeast as an advantageous
model organism

Yeast cell research was
essential to the discovery, as these cells contain the same ‘Ras’ proteins
commonly found in tumor cells, which can cause cancer in mutated form. Using
yeast as a model organism, the research team examined the connection between
Ras activity and the highly active sugar metabolism in yeast.

Prof. Johan Thevelein
(VIB-KU Leuven): “We observed in yeast that sugar degradation is linked
via the intermediate fructose 1,6-biophosphate to the activation of Ras
proteins, which stimulate the multiplication of both yeast and cancer cells. It
is striking that this mechanism has been conserved throughout the long
evolution of yeast cell to human.

“The main advantage
of using yeast was that our research was not affected by the additional
regulatory mechanisms of mammalian cells, which conceal crucial underlying
processes. We were thus able to target this process in yeast cells and confirm
its presence in mammalian cells. However, the findings are not sufficient to
identify the primary cause of the Warburg effect. Further research is needed to
find out whether this primary cause is also conserved in yeast cells.”

Story Source:

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