Background
The
Conclusion
PODXL may be a novel, non-invasive diagnostic biomarker for the detection of pancreatic cancer.
Methods
Flow cytometric analysis was performed to determine the expressions of PODXL and SCGB1D2 on the surface of cultured pancreatic cancer cells. Immunoblotting was performed to determine whether PODXL and SCGB1D2 were detectable in the media of cultured pancreatic cancer cells. A discovery-stage clinical study was performed in a cohort of 23 patients with pancreatic cancer and 51 control individuals without pancreatic disease who had been treated in the Department of Gastroenterology and Hepatology at Kochi Medical School Hospital from April 2014 to January 2016. Serum PODXL and SCGB1D2 levels were measured by enzyme-linked immunosorbent assay (ELISA).
Results
PODXL and SCGB1D2 accumulated in the protrusions of cultured pancreatic cancer cells, and they were detectable both on the cell surface and in the cultured media from these cells. The discovery-stage clinical study showed that the area under the receiver-operating characteristic curve (AUC) was 0.96 (95% confidence interval [CI] 0.91-1.000) for PODXL, 0.80 (95% CI 0.67-0.94) for SCGB1D2, and 0.78 (95% CI 0.66-0.90) for CA19-9. The AUC for PODXL was thus significantly higher than that for CA19-9 (P = 0.006). The combination of SCGB1D2 with CA19-9 did not significantly increase the AUC (0.83; 95% CI 0.70-0.96) compared with the AUC for either SCGB1D2 or CA19-9 alone (P = 0.563).