PARSORTIX ENABLES MOLECULAR CHARACTERISATION OF CTCS ISOLATED FROM FROZEN SAMPLES IN PATIENTS WITH NON-SMALL CELL LUNG CANCER AND SARCOMA
Parsortix system harvests intact CTCs for single-cell whole genomic sequencing from frozen and fresh blood samples with the same efficiency
Detection of druggable mutations in CTCs enriched from frozen samples may aid treatment decisions in the clinical setting
ANGLE plc (AIM:AGL OTCQX:ANPCY), a world-leading liquid biopsy company, is pleased to announce that a leading cancer research institute, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy, has published results of work undertaken in advanced non-small cell lung cancer (NSCLC) and sarcoma patients. The institute demonstrated that the Parsortix® system could successfully isolate circulating tumour cells (CTCs) from frozen peripheral blood mononuclear cell (PBMC) samples. PBMC samples contain any blood cell with a nucleus, including white blood cells and CTCs, but has been depleted of red blood cells which do not have a nucleus. The potential ability to process frozen samples could allow for retrospective analyses and improve sample sharing capabilities in multicentre studies.
Isolated CTCs were stained to assess phenotype and identify CTCs for single cell retrieval, followed by low-pass copy number analysis through whole genome sequencing. In addition, CTCs were analysed for clinically actionable mutations by digital PCR.
The Parsortix system was selected for its ability to harvest CTCs from mesenchymal tumours, such as sarcoma, and CTCs that have undergone epithelial to mesenchymal transition, as may occur in NSCLC. This is clinically relevant because, although the transition to a mesenchymal phenotype is associated with increased metastatic potential and worse prognosis, many CTC isolation methods, including the leading antibody-based system, only identify cells expressing epithelial markers .
CTCs could be isolated with the same efficiency from both fresh blood samples and frozen PBMCs. Subsequent automated single-CTC retrieval allowed the authors to identify CTCs based on their abnormal DNA copy number profiles, of which a similar number of CTCs were identified in both fresh and frozen samples. Long-term freezing of samples (1-3yrs), from NSCLC patients, had no detrimental effect on CTC isolation or identification. This study also showed that the majority of CTCs isolated were non-epithelial, further highlighting the importance of marker-independent CTC isolation.
Importantly, CTCs isolated from frozen NSCLC patient PBMCs using the Parsortix system were analysed for epidermal growth factor receptor (EGFR) mutations, with results showing good concordance with the primary tissue. Analysis and the potential to track druggable mutations, such as EGFR, in CTCs from frozen PBMC samples over multiple time points may help inform treatment decisions and investigate therapy response in the clinical setting, in a retrospective manner.
Dr Giulia Bertolini and Dr Vera Cappelletti, Department of Experimental Oncology, National Cancer Institute of Milan, commented:
“This study demonstrates the feasibility of CTC analyses in cryopreserved PBMCs and represents an advance in blood sample management for CTC studies, allowing for a better selection of informative time points to longitudinally investigate tumor progression/response to therapy thereby enabling retrospective studies.”
ANGLE Founder and Chief Executive, Andrew Newland, added:
“We are pleased to report on the use of the Parsortix system for the unbiased isolation and molecular characterisation of CTCs from frozen PBMC samples with similar success as from fresh blood samples. This approach may help facilitate studies that require time-dependent sampling or are completed across multiple centres. DNA analysis of the cancer cells harvested by the Parsortix system offers the potential to track druggable mutations in CTCs as an aid to future treatment decisions for patients with NSCLC.”
The research has been published as a peer-reviewed publication in the Journal Clinical Chemistry and is available online at https://angleplc.com/library/publications/.
For further information:
ANGLE plc
+44 (0) 1483 343434
Andrew Newland, Chief Executive
Ian Griffiths, Finance Director
Andrew Holder, Head of Investor Relations
