ALCAM: A Novel Surface Marker on EpCAMlow Circulating Tumor Cells

• DOI: 10.20944/preprints202207.0178.v1
• Publication Date: 2022-07-13T06:16:02Z
• Authors: Harrys Kishore Ch...; Rossana Signorelli; Teresa Maidana Giret; Oliver Umland; Marco Hadisurya; Shweta Lavania; Charles Richard J...; Ashley Nicole Mid...; Belinda Minucci B...; Ayse Burcu Ergonul; Weiguo Andy Tao; Haleh Amirian; Anton Iliuk; Aliya Mahmood Khan; Robert Alexander ...; Daniel Bilbao Cortes; Monica Tulia Garc...
• Keywords: biomarkers; pancreatic cancer; CTC; surfaceome; proteomics; flow cytometry; ALCAM; proteomics; QH301-705.5; flow cytometry; pancreatic cancer; biomarkers; surfaceome; biology_other; Biology (General); CTC; Article; 3. Good health

Background: Current strategies in circulating tumor cell (CTC) isolation in pancreatic cancer heavily rely on the EpCAM and cytokeratin cell status. EpCAM is generally not considered as a good marker given its transitory change during Epithelial to Mesenchymal Transition (EMT) or reverse EMT. There is a need to identify other surface markers to capture the complete repertoire of PDAC CTCs. The primary objective of the study is to characterize alternate surface bi-omarkers to EpCAM on CTCs that express low or negligible levels of surface EpCAM in pancre-atic cancer patients. Methods: Flow cytometry and surface mass spectrometry were used to iden-tify proteins expressed on the surface of PDAC CTCs in culture. CTCs were grown under condi-tions of attachment and in co-culture with naïve neutrophils. Putative biomarkers were then validated in GEMMs and patient samples. Results: Surface proteomic profiling of CTCs identi-fied several novel protein biomarkers. ALCAM was identified as a novel robust marker in GEMM models and in patient samples. Conclusions: We identified several novel surface bi-omarkers on CTCs expressed under differing conditions of culture. ALCAM was validated and identified as a novel alternate surface marker on EpCAMlow CTCs.