PSC-induced Galectin-1 Promotes the Malignant Behavior of Pancreatic Ductal Adenocarcinoma

Abstract

Background Galectin-1 is a β-galactoside-binding protein overexpressed in the pancreatic stellate cells (PSCs) of pancreatic ductal adenocarcinoma (PDAC), while its expression is typically low in pancreatic cancer cells (PCCs). The point at which galectin-1 expression in PCCs increases, and its association with PDAC progression, have been unclear. Methods Galectin-1 expression in PDAC and metastatic lymph nodes was investigated using an immunohistochemical assay. PANC-1 PCC cells were co-cultured with PSCs expressing different levels of galectin-1. Subsequently, galectin-1 was overexpressed in PANC-1 cells using recombinant lentiviruses, and their proliferation, invasion, anchorage-independent growth, and in vivo tumorigenicity were evaluated. Results There was intermediate galectin-1 expression in PCCs, and it was positively associated with galectin-1 expression in PSCs in the PDAC tissues. Galectin-1 was strongly expressed in the metastatic lymph nodes. In the co-culture, high galectin-1 expression in the PSCs increased the galectin-1 expression in the PANC-1 cells. The galectin-1 overexpression in the PANC-1 cells enhanced their clone formation ability, proliferation, and invasion, increased the expression of proliferating cell nuclear antigen (PCNA) and BCL-2, and decreased Bax expression, promoting the establishment and growth of tumors. Conclusion High galectin-1 expression in PSCs induces galectin-1 expression in PCCs and subsequently promotes the malignant biological behavior of PDAC.