Spalt-like transcription factor 4 as a potential diagnostic and prognostic marker of colorectal cancer.

Objective: The study aimed to investigate the role of spalt-like transcription factor 4 (SALL4) in the diagnosis and prognosis of colorectal cancer (CRC).

Methods: Between May 2008 and January 2010, 135 patients with CRC were recruited and subsequently assigned into the case group of the study. Additionally, 140 healthy individuals under identical conditions were selected as the control group. Venous blood was collected from all subjects. High expression of SALL4 was detected by immunohistochemistry, and SALL4 serum levels were detected using ELISA. A 5-year follow-up was conducted. A Kaplan-Meier curve was applied for analysis of survival rates, and a log-rank was used for univariate analysis.

Results: The case group exhibited largely positive expression levels of SALL4. Levels of SALL4 serum were much higher than those in the control group. The AUC value of CRC detected by serum SALL4 was 0.916 (95% CI was 0.881-0.951), which regarded 0.1255 μcg/l to be the point of critical value. This result was in direct relation to data from the receiver operating characteristic curve (ROC). The sensitivity and specificity of serum SALL4 levels in the diagnosis of CRC were 85.9% and 85.7%, respectively. The AUC value of CRC detected by tissue SALL4 was 0.727 (95% CI was 0.666-0.789), 0.5 was regarded as the critical value. The sensitivity and specificity of SALL4 expression in CRC tissues regarding the diagnosis of CRC was determined to be 58.6% and 86.9% respectively. The levels of SALL4 expression in serum and tissues highlighted a correlation to lymph node metastasis (LNM), differentiation degree, Dukes staging and tumor node metastasis staging. Lower serum SALL4 levels were associated with higher survival rates in CRC patients. In accordance with a COX regression, LNM, differentiation degree and SALL4 levels were determined as being prognostic factors in patients with CRC (both P< 0.05).

Conclusion: Our experimental data indicated that over expression of SALL4 was found in CRC and low expression of SALL4 was connected with high survival rate after surgery. Thus our study suggested that SALL4 could serve as a potential diagnostic and prognostic marker of CRC.