Breakthrough in limiting prostate cancer spread

10 Jun 2021

Lowering cholesterol could potentially prevent or help stop the spread of prostate cancer.

Ms Harley Robinson conducted this research on a protein called hnRNPK as part of her University of Queensland PhD program based at QIMR Berghofer Medical Research Institute.

“Laboratory tests show lowering cholesterol can help control the release of hnRNPK protein from prostate cancer cells,” Ms Robinson said.

“The protein is released in small particles called exosomes – which prostate cancer cells send out to prepare other parts of the body for cancer spread.

“A change in function of the hnRNPK protein was identified in those with advanced prostate cancer.

“The team is now developing a blood test to detect the level of released hnRNPK, which may one day be used to identify patients who should be given cholesterol-lowering drugs to prevent metastases.”

Prostate cancer that remains within the prostate is highly curable, but prognosis is poor for men with advanced prostate cancer that spreads through the body.

Less than 40 per cent of those with metastatic or Stage IV prostate cancer survive beyond five years.

Metastatic prostate cancer can also develop many years after a patient’s initial treatment and when they thought they were free of the disease.

Currently, there is no specific test to detect cancer metastasis for prostate cancer.

Doctors monitor rising levels of the Prostate Specific Antigen (PSA) protein to detect recurrence, but the protein is not elevated in all prostate cancer cases, and is not involved in the metastatic process.

Former UQ researcher and the head of QIMR Berghofer’s Precision and Systems Biomedicine Laboratory, Associate Professor Michelle Hill said the latest research had the power to improve detection and prevention.

“Our pilot study of samples from eight prostate cancer patients revealed the release of hnRNPK outside the cell was 100 per cent accurate in predicting which patients would experience cancer spreading – despite treatment,” said Dr Hill.

“We are hopeful a blood test using this biomarker would allow doctors to identify patients who should be given re-purposed cholesterol-lowering drugs to prevent cancer spread.

“It would also detect patients who are unlikely to have problems with metastases and therefore could safely avoid additional, morbid treatments.”

“The findings are very exciting. We think this hnRNPK protein might play a role in metastases in other cancers as well, but it is early days and more research is needed to confirm the link.”

The laboratory research was conducted on human cells and then validated in patient samples.

The research findings are published in the journal Clinical and Translational Medicine. The project was primarily supported by the Australian Research Council and RSL Stephens sub-branch.

It involved collaborators from Griffith University, University of Western Australia and Ochsner Health Systems, New Orleans, USA.