Discoidin Domain Receptor Tyrosine Kinase 1 (DDR1): A Novel Predictor for Recurrence of Hepatocellular Carcinoma After Curative Resection

BACKGROUND Previous studies showed that the discoidin domain receptor tyrosine kinase 1 (DDR1) is significantly elevated in a variety of cancers, and it is closely related to the occurrence and development of tumors. However, its clinical significance in hepatocellular carcinoma (HCC) is not fully elucidated. So, in this study, we aimed to systemically evaluate the prognostic value of DDR1 in HCC. MATERIAL AND METHODS A total of 200 individuals were enrolled in this study (including 120 HCC patients, 40 chronic hepatitis patients, and 40 health individuals). The contents of DDR1 in serum was measured by enzyme-linked immunosorbent assay (ELISA), while the expression level of DDR1 in para-tumor and tumor tissue was detected by immunohistochemistry staining. Kaplan-Meier, Cox regression analyses, and log-rank test were used to assess the prognostic value. RESULTS The contents of DDR1 in serum of HCC patients was significantly higher compared with chronic hepatitis patients (P<0.01) and health individuals (P<0.001). The expression level of DDR1 in tumors was higher than that in normal liver tissue, and it had relatively strong correlation with DDR1 in serum. We next demonstrated that high DDR1 has utility as a prognostic risk factor for tumor recurrence and metastasis, and it still retains its discrimination ability in low-risk groups (BCLC 0+A). Moreover, DDR1 is as an independent predictor of prognosis in HCC patients with microvascular invasion (MVI), and is strongly associated with epithelial-mesenchymal transition (EMT)-related protein. CONCLUSIONS DDR1 is a novel predictor for HCC recurrence. Integration of serum and tumor DDR1 detection into clinical management would provide convenience and enhanced accuracy in clinical practice.