Purpose: Y-box binding protein 1 (YB-1) expression in cancer cells is closely associated with malignant progression and poor prognosis in various cancers. Recently, we demonstrated that YB-1 expression in cancer cells is an immunomarker for patient prognosis and liver metastasis of gastric cancer (GC), and identified YB-1 as an excellent biomarker of angiogenic and proliferating endothelial cells in cancers. We further explored the expression patterns of YB-1 in gastric vasculature and the relationship with the clinical pathologic characteristics, as well as YB-1 phenotype in cancer cells.
Methods/patients: Immunohistochemical analysis of YB-1 was performed using 163 surgically resected primary GC specimens.
Results: YB-1 expression in cancer cells significantly differed with respect to Lauren type, JGCA classification, vascular invasion (VI), and microvessel density (MVD) of cancers (P = 0.018, P = 0.002, P < 0.001, and P < 0.001, respectively). No correlation was found between cancer-cell YB-1 expression and TNM stage or lymphatic invasion. However, YB-1 expression in vascular endothelial cells significantly correlated with N stage, M stage, TNM stage, and MVD of cancers (P < 0.001, P = 0.013, P < 0.001, and P < 0.001, respectively). Notably, cases with YB-1 expression in cancer vasculature also demonstrated YB-1 expression in cancer cells (P = 0.040).
Conclusions: YB-1 may promote GC development through its function in both cancer cells and cancer vascular cells, and thus represent a potential biomarker in this disease.