Ovarian cancer survival linked to protein, finds study

The chances of surviving ovarian cancer may be drastically affected by the production of a specific protein, according to new research led by the University of Northampton

In a study of more than 500 cases, patients with no or very low, amounts of the DNA binding protein survived twice as long than those whose tumours produced much greater levels.

The results have important implications for diagnosing and treating the disease.

Dr Lee Machado, Associate Professor in Biochemistry and lead author, said: “High levels of high-mobility group protein B1 (HMGB1) are also known to confer tumours with resistance to therapy and future studies should determine the exact mechanism of HMGB1 function in ovarian cancer.

“If this can be determined, then strategies designed to disrupt HMGB1 production may one day produce new therapies.”

The findings, published in the Journal Oncotarget, show that expression of HMGB1 was associated with reduced average survival time from almost 9 years in patients with low or absent expressing tumours, to more than 4.5 years for those with high expressing tumours.

Eleven women die from the disease every day in the UK — the sixteenth highest figure of this type in Europe.

It is still unclear the mechanism in which this protein impacts survival, but HMGB1 may play a role in increasing the amount of energy produced by tumour cells.

“This energy is then used by cancer cells to grow, multiply and ultimately spread throughout the body,” said Dr Machado, who conducted the research with colleagues from the University of Nottingham.

The team looked at tissue samples from 194 cases of epithelial ovarian cancer treated at Nottingham University Hospitals and 360 cases that had been treated at Derby City Hospitals.

High levels of the protein were associated with poor progression free survival in the Nottingham cases and poor overall survival in the Derby ones.

In the UK, more than 7000 women a year develop the disease, with epithelial ovarian cancer the most common type. Just over half of diagnoses are in women above the age of 65.

Chances of surviving the disease for longer than 5 years drop dramatically from around 90% to less than 20, when comparing women with early and late stage diagnoses.

Dr Machado said: “It could really improve both our understanding of ovarian cancer biology and treatment of these patients.”

The HMGB1 protein has so far been implicated in a range of cancers including bowel, lung and liver and recent studies have focused on its ability to protect cancer cells from stresses, such as chemotherapy, through a process known as autophagy.

References

  1. L. Machado et al., "High mobility group protein B1 is a predictor of poor survival in ovarian cancer," Oncotarget, 1949-2553 (2017).

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