Serum levels of PTEN mRNA in colorectal cancer: a case-control study

Background: The purpose of this study was to identify the expression of phosphatase and tensin homolog (PTEN) and its diagnostic value in colorectal cancer (CRC).Methods: The expression level of serum PTEN at mRNA and protein level were determined using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analyses, respectively. Chi-square test was employed to explore the relationship between PTEN expression and clinical features of CRC patients. The receiver operating characteristics (ROC) curve was established to evaluate the diagnostic performance of PTEN in CRC.Results: The expression of serum PTEN was significantly lower in patients with CRC than that in healthy controls both at mRNA and protein level (p < .05). Also, the low PTEN expression was significantly related to serosal invasion, lymph node metastasis and Ki-67, but had no relation with age, sex, tumor depth and tumor site. The area under ROC curve of 0.810 corresponding with a sensitivity of 97.79% and a specificity of 70.31% were obtained, which suggested PTEN could act as a diagnostic marker for CRC.Conclusion: Altogether, serum PTEN expression was down-regulated and it participated in the development of CRC. Besides, it could act as an efficient and independent diagnostic marker for CRC patients.