Culture of circulating tumour cells derived from non-small cell lung cancer

Background: Tumour tissue-based information is limited. Liquid biopsy can provide valuable real-time information through circulating tumour cells (CTCs). Profiling and expanding CTCs may provide avenues to study transient metastatic disease. Methods: 70 NSCLC patients were recruited. CTCs were enriched using the spiral microfluidic chip and a RosetteSep™ using bloods from NSCLC patients. CTC cultures were carried out using the Clevers media under hypoxic conditions. CTCs were characterized using immunofluorescence and mutation-specific antibodies for samples with known mutation profiles. Exome sequencing was used to characterized CTC cultures. Results: CTCs ( > 2 cells) were detected in 38/70 (54.3%) of patients ranging from 0-385 CTCs per 7.5ml blood. In 4/5 patients where primary tumours harboured an EGFR exon 19 deletion, this EGFR mutation was also captured in CTCs. ALK translocation was confirmed on CTCs from a patient harbouring an ALK-rearrangement in the primary tumour. Short term CTC cultures were successfully generated in 9/70 NSCLC patients. Whole exome sequencing confirmed the presence of somatic mutations in the CTC cultures with mutational signatures consistent with NSCLC. Conclusions: This study demonstrates a workflow for ex vivo culture of CTCs from NSCLC blood samples