p53 Prions – Novel Biomarker for Circulating Tumor Cells

Patent-pending Test Kit by OncoLab Launched

• p53 aggregates frequently present in circulating tumor cells (CTC)
• Novel tests by OncoLab (Austria) identify cancer cells via p53 prions
• Kits for use with tissues, cells, and blood available
• OncoLab’s range of IF and PCR-based circulating rare cell (CRC) detection kits extended

Wiener Neustadt (Austria), September 22^nd, 2021. A patent-pending new technology allows more reliable identification of circulating tumor cells (CTC). The technology is based on the identification of p53 aggregates (“p53 prions”) using Blood-based Biopsy tests (BBB) developed by OncoLab GmbH, Austria. p53 is a well-known tumor suppressor protein. Mutations of the gene can cause prion-like aggregation of p53-proteins. OncoLab has developed tests for amplified immuno-labeling of these aggregates using proprietary technology of Navinci Diagnostics AB, the Swedish specialist for visualizing proteins and their protein-protein interactions and post-translational modifications.

“Tp53 mutations can cause misfolding of the p53 protein leading to aggregation”, explains Prof. Zeillinger, CEO of OncoLab. “The misfolded proteins can act prion-like causing also normal p53 proteins to bind to the aggregates. One of our tests can identify these aggregates in immobilized tissue sections or cells – another one in blood and other bodily fluids, allowing the identification of CTCs and DTCs (disseminated tumor cells) that often contain p53 aggregates.” In fact, more than half of all cancer cells contain Tp53 mutations that may lead to misfolded proteins and aggregation. Identifying those aggregates can greatly improve the reliability of CTC identification as Prof. Zeillinger adds: “Most tests for identifying CTCs are based on detection of Epithelial Adhesion Molecules (EpCAM) or cytokeratins. But not all CTCs express these biomarkers, and they are often downregulated during tumor progression. An additional marker, especially one expressed by a well-known tumor suppressor gene, is a highly desirable addition in the test kit market for CTCs, and we are very pleased to offer this novel assay for p53 prions.”

Besides p53 aggregates the OncoLab’s CTC test “nPAC^TM AMYLOplex^TM CTC-p53” also detects known CTC markers (several cytokeratins) as well as leucocyte markers. It is based on immunofluorescence, a method that allows a direct identification of CTCs and provides information about the morphology and numbers of CTCs. Immunofluorescence staining is also used in OncoLab’s “nPAC^TM CRC IF” series of tests that is offered in collaboration with US-based AxonDx, LLC.

Further tests for other aggregated cancer proteins are under development at OncoLab which was also the first company to offer an extensive range of products for BBB based on either PCR or immunofluorescence. The development of the p53 prion test kits was a joint effort with the Swedish company Navinci that also closely collaborates with Uppsala University. Prof. Ulf Landegren of the Department of Immunology, Genetics and Pathology, Molecular Tools, comments: “Over recent years my group has collaborated with Navinci to develop the necessary technologies for routine identification of aggregated tumor proteins. We are excited to now see the first kits hitting the market – and the potential for further tests is enormous.” Robert Gunnarsson, CEO Navinci Diagnostics AB: “As OncoLab has proven, the proximity ligation assay technique is ideal to study aggregated tumor proteins and we are very happy that we together with OncoLab can provide novel tools to enhance the diagnosis of cancer and find better treatments”.

OncoLab brands the entire range of tests for aggregated proteins “AMYLOplex^TM”. The “AMYLOplex^TM p53” test is available for research use (RUO) and a CE-IVD marked version for diagnostic purposes is following within the next months.

As the world-wide first supplier of CTC test kits based on immunofluorescence and kits based on PCR, and now adding another “first” by offering the p53 prion test kits, OncoLab is regarded as one of the most innovative companies in the growing CTC/CRC diagnostic market. The full product range of the company will be presented at the 5^th ACTC – Advances in Circulation Tumor Cells meeting, 22^nd – 25^th of September, Kalamata, Greece.

About OncoLab Diagnostics GmbH (September 2021)

OncoLab develops, manufactures and distributes innovative and precise diagnostic tests with a focus on Blood-based Biopsy tests. Products are available for detecting circulating tumor, endothelial and stromal cells as well as immune cells. The company is certified according to ISO 9001:2015 and ISO 13485:2016 and member of the International Society of Liquid Biopsy (ISLB) and the European Liquid Biopsy Society (ELBS).

About Navinci (September 2021)

Navinci (formerly known as Olink Bioscience) is a Swedish life science company that develops and markets proprietary in situ proximity ligation assays to specifically monitor proteins, their interactions and modifications. The technology provides an important tool for spatial biology and reveals the responses to disease and drug treatment directly in the tissue microenvironment.

Contact

Prof. Robert Zeillinger, Dr.phil.

OncoLab Diagnostics GmbH

Viktor Kaplan-Str. 2, Objekt E

2700 Wiener Neustadt, Austria

T:  +43 2622 32913-60

M: +43 664 4240373

W: www.oncolab.at