EpCAM has also been targeted as the putative marker of epithelial CSCs of ovarian cancer and pancreatic cancer [24, 30]. EpCAM was found significantly related to large tumor size and poor survival outcomes through IHC, which was similar to a previous study . EpCAM was also found high expressed in peritoneal metastasis of GC, indicating that only GC cells with high expression of EpCAM might metastasize to the peritoneum . In some experiments, the capabilities of cell proliferation and tumor formation in nude mice of GC cell lines were impaired after EpCAM downregulation . However, another study reported that the patients with loss of EpCAM expression had significantly worse prognosis than those without loss and in stage I and II disease, loss of EpCAM expression was related to aggressive tumors .