Purpose: This study was designed to investigate the role of PDGF-DD secreted by gastric cancer-derived mesenchymal stem cells (GC-MSCs) in human gastric cancer progression.
Methods: Gastric cancer cells were indirectly co-cultured with GC-MSCs in a transwell system. The growth and migration of gastric cancer cells were evaluated by cell colony formation assay and transwell migration assay, respectively. The production of PDGF-DD in GC-MSCs was determined by using Luminex and ELISA. Neutralization of PDGFR-β by su16f and siRNA interference of PDGF-DD in GC-MSCs was used to demonstrate the role of PDGF-DD produced by GC-MSCs in gastric cancer progression.
Results: GC-MSC conditioned medium promoted gastric cancer cell proliferation and migration in vitro and in vivo. Co-culture with GC-MSCs increased the phosphorylation of PDGFR-β in SGC-7901 cells. Neutralization of PDGFR-β by su16f blocked the promoting role of GC-MSC conditioned medium in gastric cancer cell proliferation and migration. Recombinant PDGF-DD duplicated the effects of GC-MSC conditioned medium on gastric cancer cells. Knockdown of PDGF-DD in GC-MSCs abolished its effects on gastric cancer cells in vitro and in vivo.
Conclusions: PDGF-DD secreted by GC-MSCs is capable of promoting gastric cancer cell progression in vitro and in vivo. Targeting the PDGF-DD/PDGFR-β interaction between MSCs and gastric cancer cells may represent a novel strategy for gastric cancer therapy.