SATB1 expression is correlated with β-catenin associated epithelial-mesenchymal transition in colorectal cancer

SATB1, a global gene regulator, has been implicated in the growth and metastasis of multiple cancers, including colorectal cancer. While the understanding about the role of SATB1 in CRC remains limited. The aim of our study is to investigate the expression of SATB1 in CRC, and the relationship between SATB1 expression pattern and clinicopathological variables. A further aim is to analyze the correlation between SATB1 expression and epithelial-mesenchymal transition in CRC. Immunohistochemical expression of SATB1, β-catenin, E-cadherin, CK20, Vimentin, SMA, and desmin were assessed in a cohort of 200 patients using tissue microarrays. SATB1 was expressed in 133 (66.5%) CRC primary lesions, 14 (28%) adjacent colorectal mucosa specimens, and 60 (75%) corresponding lymph node metastases. The expression level of SATB1 was significantly higher in lymph node metastases than in CRC primary lesions and normal mucosa (P = 0.000). High expression of SATB1 in CRC was strongly correlated with poor differentiation of tumor tissues (P = 0.000). High expression of SATB1 was significantly correlated with aberrant expression of β-catenin (P = 0.0005), low expression of E-cadherin (P = 0.000) and CK20 (P = 0.000) and with high expression of Vimentin (P = 0.001). No SMA or desmin protein was expressed in the CRC cells. Our results suggested that high expression of SATB1 is significantly correlated with poor differentiation of CRC. SATB1 might promote the epithelial-mesenchymal transition by increasing the aberrant expression of β-catenin.