Esophageal cancer-associated fibroblasts promote proliferation, invasion, migration and resistance to chemoradiotherapy in esophageal squamous carcinoma cells

Correlation between tumor microenvironment and chemoradiotherapy resistance is unclear in esophageal squamous cell carcinoma (ESCC). We therefore sought to investigate the influence of esophageal cancer-associated fibroblasts (CAFs) on growth, invasion, migration, and chemoradiotherapy resistance in esophageal squamous cancer cells. For primary culture, CAFs were isolated from a patient who was pathologically confirmed esophageal squamous cancer after surgery. After 48 h culture of CAFs (which identified by immunohistochemical method), we collected the purified medium which we called CAFs medium. The CAFs medium was used to culture esophageal squamous cancer cells (KYSE-150) and the morphologic changes of cells in this medium were observed and compared with KYSE-150 cells cultured in normal medium (10% FBS RPMI-1640). The growth rate, migration ability and invasion ability of KYSE-150 cells were detected by MTS assay, wound-healing assay and transwell assay. The effect of CAFs on the sensitivity of radiotherapy and chemotherapy in KYSE-150 cells was determined by MTS assay and colony forming assay. Results showed that a dramatic morphological change was observed in KYSE-150 cells that were cultured in the CAFs medium. Compared with normally cultured KYSE-150 cells, proliferation activity, migration ability and invasion ability of KYSE-150 cells cultured in CAFs medium were significantly enhanced. MTS assay and colony forming assay also showed that CAFs medium efficiently decreases the chemosensitivity and enhance the radiotherapy resistance in KYSE-150 cells (P < 0.05). Altogether, our study suggested that primary cultured esophageal CAFs can promote proliferation, migration, invasion and enhance resistance to chemoradiotherapy in esophageal squamous cancer.