Association of High Expression Levels of SOX2, NANOG, and OCT4 in Gastric Cancer Tumor Tissues with Progression and Poor Prognosis.

Background: Expression of the essential regulator genes, SOX2, NANOG, and OCT4, so-called as stemness factors, is prerequisite for the tumorigenic capability of cancer stem cells (CSCs) and their potential role in the formation and progression of various human cancers.

Methods: In this study, the expression levels of SOX2, NANOG, and OCT4 were quantified by a qRT-PCR method in 100 gastric cancer tumor tissues vs the paired adjacent normal tissues. Then, the relationship between the expression of the three genes in gastric cancer tumor tissues and the clinicopathological characteristics and overall survival of patients was investigated.

Results: Higher expression levels of SOX2, NANOG, and OCT4 were found in gastric cancer tumor tissues compared with those in paired adjacent normal tissues (P = 0.0001). Overexpression of the mentioned genes in gastric cancer tumor tissues was resolved to be significantly associated with tumor size (P < 0.05), TNM stage (P = 0.001), tumor grade (P < 0.01), and shortened overall survival time (P = 0.0001).

Conclusions: These findings indicted that the stemness factors SOX2, NANOG, and OCT4 are significantly overexpressed in gastric cancer and may serve as potential biomarkers of gastric cancer progression and prognosis.