Analysis of circulating blood and tissue biopsy PDX1 and MSX2 gene expression in patients with pancreatic cancer: A case–control experimental study

Early diagnosis of pancreatic cancer (PC) is based on endoscopic ultrasound (EUS). However, EUS is invasive and requires a high level of technical skill. Recently, liquid biopsies have achieved the same sensitivity and specificity for the diagnosis of numerous pathologies, including cancer. Insulin-promoting factor 1 (PDX1) and Msh-homeobox 2 (MSX2), 2 homeotic genes, have been confirmed to be related to pancreatic oncogenesis. The aim of this study is to establish the diagnostic utility of circulating serum levels of MSX2 and PDX1 expression in patients with PC. A prospective study was conducted from January 2014 to February 2017. Patients with a suspected diagnosis of PC who underwent fine needle aspiration biopsy guided by EUS (EUS-FNA) were included in the study, in addition to non-PC control subjects. Both tissue and blood serum samples were submitted to histopathological analysis and measurement of PDX1 and MSX2 gene expression by means of qRT-PCR. Patients were divided into non-PC, malignant pathology (MP), or benign pathology (BP) groups. Significant differences in both MSX2 [2.05 (1.66–4.60) vs 0.83 (0.49–1.60), P = .006] and PDX1 [2.59 (1.28–10.12) vs 1.02 (0.81–1.17), P = .036] gene expression were found in blood samples of PC compared with non-PC subjects. We also observed a significant increase in MSX2 transcripts in tissue biopsy samples of patients diagnosed with MP compared with those with BP [1.98 (1.44–4.61) and 0.66 (0.45–1.54), respectively, P = .012]. The ROC curves indicate a sensitivity and specificity of 80% for PDX1 and 86% for MSX2. Gene expression of MSX2 in tissue samples obtained by EUS-FNA and serum expression of MSX2 and PDX1 were higher in patients with PC.