Effect of umbilical cord mesenchymal stem cells on biological characteristics of esophageal cancer EC1 cells

Abstract

Objective: To investigate the effects of human umbilical cord mesenchymal stem cells (MSCs) on the proliferation, apoptosis, migration, invasion and stemness of esophageal cancer EC1 cells. Methods: Human umbilical cord mesenchymal stem cells were isolated and cultured in vitro, and cell phenotype was identified by flow cytometry. MSCs or their conditioned medium were co-cultured with esophageal cancer EC1 cells. The effects on the proliferation, apoptosis, migration, invasion and stemness of EC1 cells were examined by cell counting kit-8 (CCK-8), flow cytometry, Transwell, quantitative real-time polymerase chain reaction (RT-qPCR) and spheroid formation assays. Results: MSCs inhibited the proliferation of EC1 cells in a concentration dependent manner. When the ratio of MSCs to EC1 cells was 0∶1, 1∶1, 2∶1, 5∶1, the apoptotic rates of EC1 cells were (4.07±0.34)%, (8.90±0.36)%, (10.80±0.50)% and (15.23±1.06)%, respectively, suggesting that MSCs promoted the apoptosis of EC1 cells in a concentration dependent manner (all P<0.05). The expression levels of OCT2, SOX2, KLF4, CXCR4 and CXCR7 in EC1 cells cultured in 80% conditioned medium were 0.53±0.03, 0.49±0.02, 0.73±0.09, 0.57±0.05 and 0.24±0.02, respectively, which were lower than those in the regular medium group (all P<0.05). The numbers of migrated cells in regular medium as well as 10%, 40%, and 80% conditioned medium were 287.3±21.6, 280.7±15.5, 264.3±16.8, and 257.7±8.0, respectively. Meanwhile, the numbers of invasive cells were 194.3±16.6, 213.7±24.3, 221.0±16.0, (252.0±20.4), respectively. There was no significant difference between the groups (all P>0.05). Conclusion: Human umbilical cord mesenchymal stem cells can inhibit the proliferation, promote apoptosis and reduce the stemness, and have no significant effect on the migration and invasion of EC1 cells.