Investigation of Microsatellite Instability BAT 25 and BAT 26 in Breast Cancer Patients by Conventional PCR


Abstract:Background: Breast cancer is the most common cancer among women worldwide, comprising 23%of the 1.1 million female cancers that newly diagnosed each year.Aims: Investigate the existence of microsatellite instability (MSI) in breast cancer of patients.Settings and Design: Fifty female patients with invasive ductal breast carcinoma (IDC) collected.Inclusion criteria of subjects include female patients with diagnostic feature of breast cancer and agerange 26-42 years old untreated with chemotherapy or hormonal therapy.Methods and Material: DNA had be extracted from frozen tissue samples of breast cancer. Thisprotocol done according to the kit manufacture’s manual of QIAamp DNA Mini kit from Qiagen –USA. All samples tested for MSI bysingleplex PCR reactions using two microsatellite markers BAT25 and BAT 26.PCR achieved in a final volume of 50 μl and after thermal cycles, gel visualizationperformed.Statistical analysis used: The significance of differences in proportions was analysed by the Fisher’sexact testwith SPSS version 20 and P values equal or less than 0.001 considered statisticallysignificant.Results: PCR demonstrating microsatellite instability in 13 (26%) of the 50 breast cancer sample.Eight (16%) of 50 breast cancer sample were BAT 25 positive with a PCR product size of 124 bp,while 5 (10%) of 50 breast cancer sample were BAT 26 positive with a PCR product size 121bp.Conclusions: The result suggest strong evidence that microsatellite instability (MSI) at the BAT 25and BAT 26 and have involved in the pathogenesis of the great majority of breast cancers.