SALL4 as a new biomarker for early colorectal cancers

Colorectal cancer (CRC) is one of the most common causes of cancer-related death worldwide, and there is an urgent need to identify critical diagnostic and prognostic factors for early detection of the disease. Our aim in this study was to elucidate absolute copy number of SALL4 mRNA in the peripheral blood and serum of CRC patients to evaluate its probable prognostic or diagnostic value for CRC. Peripheral mononuclear cells from 111 cases were examined using absolute quantitative real-time RT-PCR to assess the exact copy number of SALL4 and CEA mRNA. Receiver operator characteristic (ROC) curves were also depicted to detect the sensitivity and specificity of SALL4 mRNA. The blood copy number of SALL4 in recruited CRC patients was significantly higher than healthy controls (p = 0.0001). This high copy number was not only inversely associated with the depth of tumor invasion (p = 0.045), but also was significantly correlated with the high grade of tumor differentiation (p = 0.029) and sex (p = 0.027). Furthermore, the copy number of SALL4 was elevated in all examined serum samples (p = 0.0001) in significant association with high grade of tumor differentiation (p = 0.026) and patients' age (p = 0.012). ROC analysis indicated 96.1 and 95 % sensitivity and specificity of SALL4 for CRC screening, respectively. Early detection of CRC is directly correlated to improved outcomes, increased survival rates and reduced mortality. Our results can introduce SALL4 as a critical biomarker for efficient screening of patients to detect early stages of CRC.