Study on Determination of Mutations of the PTEN Tumor Suppressor Gene in Various Cancer Types

摘要

Among all tumours diagnosed worldwide, gastric adenocarcinoma, breast and endometrium are the most frequent types of malignancy. In addition to these cancer types, PTEN frequently is mutated or inactivated in glioblastoma, melanoma, and cancers of the prostate. The severity of PTEN irregularities strongly correlates with the tumor stage and grade. For example, complete loss of PTEN expression is found more frequently in metastatic cancer than in primary tumors. For this reason, the aim of this study was to assess the contribution of PTEN gene to commonly cancer types in the Turk population and investigate mutation of tumor suppressor gene PTEN in gastric cancer, breast cancer and endometrium cancer types. In our study, DNA was obtained from different tissue types such as, gastric adenocarcinoma, breast and endometrium cancer samples, amplified, screened for 2 exons (exon 1 and exon 2) of the PTEN gene by PCR-SSCP and then confirmed by sequencing. There was only one sample that presented an alteration and that was a transversion. Our results corroborate the hypothesis that somatic alterations in the PTEN gene are rare events in gastric cancer. Furthermore, Inherited changes in several other genes, including PTEN have been found to increase the risk of developing breast cancer and endometrium cancer. This case affirmed that, for establishment of a correct diagnosis, especially for rare clinically overlapping syndromes, molecular testing is usually the only reliable method.