Expressions and significances of TTF-1 and PTEN in early endometrial cancer.

OBJECTIVE: To analyze the expressions and significances of TTF-1 (Thyroid transcription factor-1) and PTEN (Phosphatase and tensin homolog) in early endometrial cancer.

PATIENTS AND METHODS: 41 patients with endometrial cancer, 38 patients with proliferative endometrium and 13 patients with normal endometrium, were selected. The fluorescence quantitative PCR (polymerase chain reaction) was used to detect the expression levels of TFF-1 and PTEN mRNAs (Messenger ribonucleic acids) in the above three endometria, and their relations with clinical pathological characteristics were analyzed. The RT-PCR (reverse transcription-polymerase chain reaction) was employed to detect the expression levels of miR-135b, miR-125b and Snail mRNAs in the three endometria, and their correlations with the expressions of TTF-1 and PTEN mRNAs, were analyzed.

RESULTS: The expression levels of TFF-1 and PTEN mRNAs in endometrial cancer tissues were significantly lower than those in the other two groups, while those in normal endometrium tissues were the highest, and the differences were statistically significant (p < 0.05). There were no significant differences in the menstruation status and the expression levels of TFF-1 and PTEN mRNAs between adenocarcinoma and squamous carcinoma (p > 0.05). With the increase of FIGO (International Federation of Gynecology and Obstetrics) stage and depth of invasion, as well as the metastasis of pelvic lymph nodes, the expression levels of TFF-1 and PTEN mRNAs were significantly decreased, and the differences were statistically significant (p < 0.05). The expression level of miR-135b mRNA in endometrial cancer was significantly higher than that in the other two groups, while that in normal endometrium was the lowest. The expression levels of miR-125b and Snail mRNAs were significantly lower than those in the other two groups, while those in normal endometrium were the highest; the differences were statistically significant (p < 0.05). Expression levels of TTF-1 and PTEN mRNAs were negatively correlated with the expression level of miR-135b mRNA, and positively associated with the expression levels of miR-125b and Snail mRNAs (p < 0.05). The results from the ROC (Receiver Operating Characteristic) model showed that, for the diagnosis of endometrial cancer with TTF-1 mRNA, the sensitivity was 86.5%, the specificity was 84.2%, the accuracy (area under curve - AUC) was 0.823, 95% CI (confidence intervals) = 0.762-0.921, p = 0.012. For the diagnosis of endometrial cancer with PTEN mRNA, the sensitivity was 85.3%, the specificity was 83.6%, the accuracy was 0.842, 95% CI = 0.785-0.936, p = 0.010.

CONCLUSIONS: TTF-1 and PTEN can be used as molecular markers for the early diagnosis of endometrial cancer, which are closely related to clinical features and may affect tumor progression by regulating the proliferation activity of tumor cells.