Researchers have identified three new prostate cancer biomarkers that could improve the visibility of cancer cells used by pathologists to grade disease severity. The new technique could help identify which patients need urgent treatment and which don’t, potentially improving outcomes for millions of men.
In 2020, more than 1.4 million men will be diagnosed with prostate cancer and an estimated 375,304 will die. Prostate cancer survival depends on several factors, including the stage and grade of the cancer, the patient’s age and general health, and response to treatment.
Gleason score is the main basis for determining the grade of prostate cancer. A pathologist looks at the stained cancer cells under a microscope to see how they look like healthy cells (low score) or abnormal and invasive cells (high score). This shows how likely the cancer is to progress and spread. Cancers with low scores grow more slowly and are less likely to spread than cancers with high scores.
The problem with using Gleason scoring is that since it is performed by humans, it can be subjective. Two observers may come to different conclusions. Now, in a new study led by the University of South Australia, researchers have identified three new biomarkers that may help identify and differentiate potentially aggressive prostate cancer cases.
The researchers aimed to use changes in cell biology associated with different grades of prostate cancer to improve current diagnostic methods. They studied the endosome-lysosome system, an organelle involved in cancer development, and three proteins in this system: Appl1, Sortilin and Syndecan-1. The study found that these protein biomarkers allowed pathologists to visualize more features in tissue samples than they could using conventional stains.
The researchers used tissue samples donated by 114 men diagnosed with prostate cancer who underwent radical prostatectomy, which is surgery to remove the entire prostate and surrounding tissue, between 2006 and 2014.
For each patient, tissue samples were cut into four serial sections. The first part was stained using traditional methods and sent to a committee of 11 international urogenital pathologists who reached a consensus and assigned each patient a grade. The remaining sections were labeled with biomarkers Appl1, Sortilin and Syndecan-1, respectively. Each protein causes a different cellular material to be highlighted. These three tissue sections were then presented to the same 11 pathologists—at least one week apart to limit the possibility of memory bias—and they agreed to assign each patient a grade.
Researchers have found that using three novel biomarkers improves prognosis prediction in prostate cancer patients compared with traditional methods of staining tissue. This, they say, will help in grading prostate cancer to determine which patients need urgent treatment, leading to improved outcomes.
“These biomarkers are very sensitive and specific in accurately observing cancer progression and confirming its grade,” said study co-author Robert Brooks. “This discovery has prompted the commercial development of a test designed to determine how advanced and aggressive a cancer is and whether it requires immediate treatment.”
The researchers partnered with Australian company Envision Sciences to develop the biomarker detection technology used in the study. Envision Sciences has signed a commercialization agreement with Quest Diagnostics, one of the largest diagnostic pathology companies in the US, to bring the technology into clinical practice.
Clinical trials using the new technology are expected to begin in Australia pending successful results in the US.
The study was published in the journal cancer.
source: University of South Australia