Nucleostemin and TWIST as predictive markers for recurrence after neoadjuvant chemotherapy for esophageal carcinoma

We recently demonstrated that overexpression of the nucleolar GTP-binding protein nucleostemin drives the fraction of genetically-defined tumor cells that exhibit markers and tumorigenic properties of tumor initiating cells. More specifically, cells that constitutively express elevated levels of nucleostemin exhibit increased TWIST expression; expression of genes that induced pluripotent stem cells; enhanced radioresistance; tumor formation, even when small numbers of cells are implanted; and an increased propensity to metastasize. An immunohistochemical analysis of cancer stem cell markers, such as nucleostemin and TWIST has not been conducted in surgically-resected esophageal squamous cell carcinomas after neoadjuvant chemotherapy. In the present study, we examined the expression of CD133, CD44, nucleostemin, guanine nucleotide-binding protein-like 3-like, and TWIST by immunohistochemistry in a series of 54 surgically-resected specimens of esophageal squamous cell carcinomas after neoadjuvant chemotherapy. We identified that high nucleostemin proportion, TWIST intensity, and advanced pathological N stage were significantly correlated with poor relapse-free survival. Together, these observations imply nucleostemin and TWIST as the predictive markers for postoperative recurrence.