OncoLab Diagnostics GmbH now offers tests combining PCR and immunofluorescence staining for faster and easier identification of circulating tumour cells (CTCs) for blood-based biopsy tests (BBB).
PCR and IF staining are, currently, the two different technologies used to identify CTCs in liquid biopsy.
“But due to the heterogeneity of CTCs, both methods might miss some”, explains Prof. Zeillinger, CEO of OncoLab. “The combination of immunofluorescence and PCR-based CTC detection can overcome this problem.”
PCR-based tests detect CTCs by identifying cancer-specific DNA or RNA markers. This indirect approach is highly sensitive and allows – under certain circumstances – the integration of both, the RNA expression of cancer-specific biomarkers and the expression of serum protein biomarkers, into one diagnostic model. Furthermore, with this approach up to 50 markers can be analysed in one run.
In comparison, immunofluorescence tests allow direct identification of CTCs by binding fluorescent labels on the membrane and intracellular structures of the cells. This enables the user to gather information about the morphology and number of CTCs.
Tests that are available at OncoLab include a Real-Time quantitative PCR test for identifying CTCs expressing CK-19 (cytokeratin-19), a marker of epithelial cells. research use only (RUO)-version of the test is suitable for analysing the expression of CK-19 for identifying CTCs and in tissues as well as in cell cultures.
A CE-IVD-version for the detection of breast cancer-related CTCs is currently under development. This test will not require any enrichment of CTCs although it will be compatible with most enrichment methods. Further tests that will soon be launched include qPCR tests for detecting CTCs in ovarian, cervical and endometrial cancers as well as in small cell lung cancer, prostate cancer and neuroendocrine tumour diseases.
The Austrian company also has immunofluorescence tests for identifying circulating endothelial cells as well as circulating stromal cells, in the product pipeline.