Molecular characterization of invasive subpopulations from an esophageal squamous cell carcinoma cell line.

Background: Once diagnosed, esophageal cancer has a very low overall 5-year survival rate. This study investigates the mechanisms behind the invasiveness and severity of esophageal squamous cell carcinoma (ESCC).
Materials and Methods: Transwell invasion chamber was used to subdivide one Taiwanese ESCC cell line, CE81T/VGH, into sublines (CE81T-0, CE81T-1, CE81T-2, CE81T-3, and CE81T-4) in four rounds of assays; the most invasive were identified, and various factors related to their invasiveness measured.
Results: CE81T-1, CE81T-2, CE81T-3 and CE81T-4 sublines were significantly more invasive than the parental cells (CE81T/VGH) and CE81T-0 subline. CE81T-1 and CE81T-4, the sublines we chose to study further, had significantly greater colony-forming ability (3.5- to 2.7-fold) and wound migrating activity (1.95- to 2.6-fold) than the parental cells in vitro (p<0.01). They also displayed greater tumorigenesis in immunodeficient BALB/c Foxlnn mice than the parental cells. We found an inverse correlation between expression of tissue inhibitor of metalloproteinase-2 and invasive ability, and a significant positive correlation between expressions of matrix metalloproteinase-1, vimentin, and p-Src (pY416) in these cell lines and their invasiveness (all p<0.05).
Conclusion: The subline model may be used to study the molecular and genetic mechanisms underlying the invasion and metastasis of ESCC.