Abstract

SOX2 correlates with metastases in rightsided colon cancer The evidence of SOX2 and ß-catenin in the cell core of colorectal cancer and its distant spread is of high scientific relevance, especially for the prognosis of tumor malignity. ß-catenin is a central transcription factor of the canonical Wnt/ß-catenin pathway. The results showed a high expression of ß-catenin in the cell cores of rightsided colon cancer. The reason for the accumulation of ß-catenin in the cell core is due to a dysregulation of the canonical Wnt-/ß-catenin signal pathway, which is caused by a high percentage (85%) loss of the tumorsurpressor gene adenomatous polyposis coli (APC). The aim in this study design was to examine the hypothesis, if the expression of SOX2 in context of the migrating cancer stem cell concept would give the prove of correlation and also if the relation of ß-catenin and SOX2 expression in rightsided colon cancer would show significant results. Material: A case-control-study with 114 patients with rightsided colon cancer (57 patients with distant spread group M1 and 57 patients without distant spread group M0) was designed in close collaboration with the Munich Cancer Registration Center. Methods: In a first step the 114 tumor paraffin-blocks were treated with preparing procedures to generate serial sections of 5 μm thickness. Immunohistochemical stainings with SOX2 specific rabbit monoclonal antibody and with anti-ß-catenin mouse monoclonal antibody were produced according to protocols; the score was developed and applied for the collection independently by two observers. Results: In the study I was able to show, that the expression of SOX2 correlates significantly with lymph-node and liver metastases. Also the expression of ß-catenin correlates significantly with lymph-node and liver metastases. In the cases of high expression of SOX2 and ß-catenin found in the rightsided colon cancer there was even a 100% significant correlation with metastases. Conclusion: SOX2 and also the combination of SOX2 and ß-catenin are relevant markers for a significant correlation of lymph-node metastases and distant spread in rightsided colon cancer. Therefore there is a high diagnostic value of these tumor markers for the prognosis of the malignity of this disease.