p53 tumor suppressor gene mutation in ovarian cancer in Thai patients.

ABSTRACT

OBJECTIVES: To characterize molecular mutations of p53 gene in Thai ovarian cancer and compare the mutations with their pathological and clinical findings. MATERIAL AND METHOD: Direct DNA sequencing of hot spot region of p53 gene (exons 5 to 8) from 28 primary ovarian cancer tissues, 2 metastatic tumors and their paired blood samples was performed. The detected mutations were compared to the pathological and clinical findings and responsiveness to treatments after 36 months of follow-up. RESULTS: One insertion and 4 point mutations in exon 5 of p53 gene were found in 5 out of 28 (18%) ovarian cancer patients. There was no mutation in the paired blood samples. The histological types of the detected tumors were 3 endometrioids and 2 serous cystadenocarcinomas. All 5 patients were in stage I to IV disease and showed overall 4 out of 5 (80%) complete response until 36 months after surgery followed by chemotherapy, compared to 14 out of 28 (50%) of complete response in all cases of ovarian cancer. CONCLUSION: The authors found 5 cases of ovarian cancer patients with p53 gene mutations giving the same response to complete standard treatment as all cases. Significant factors affecting responsiveness of these patients depended more on stages, grades and histological cell types of the cancer.