Identification of p53 Gene Mutations among Iranian Patients Involved with Esophageal Squamous Cell Carcinoma: the Efficiency of the Two Different Methods

tation in p53 tumor suppressor gene is highly frequent in different cancers. It was reported that the efficiency of Microarray and ABI 310 system in identification all types of p53 gene mutations (for fresh tissues) are 95% and 91%, respectively and detection of point mutations by Microarray and ABI 310 system are 100% and 92%, respectively. In the present study, Microarray and ABI 310 analysis were used to detect p53 gene mutations in esophageal carcinoma from archived tissues. For this purpose, formalin-fixed, paraffin-embedded esophageal tissues from cancer patients diagnosed with esophageal squamous cell carcinoma (ESCC) were collected. DNA was extracted by Microdissection method (with and without laser) and was purified with Microcon 50 filters (Millipore) before performing PCR. p53 gene mutations were identified in 9 analyzed samples by ABI 310 system. For these samples, the genomic DNA were obtained from microdissected-samples without laser. Microarray could detect mutations in 3 of 9 analyzed ESCC specimens from Iranian patients, which were identified p53 gene mutations by ABI 310 system. In addition, in laser-microdissected samples mutations were identified by ABI 310 system. The extracted DNA obtained from laser-microdissected samples was insufficient for the assessment of p53 gene mutations with Microarray. It was determined that Microarray was dependent on the amount of tissues used in DNA extraction. The results indicated that the choice of method for extracting DNA from test samples to assess mutation in p53 gene is very important. The efficiency of ABI 310 system and Microarray in detection of p53 gene mutations (for exons 5-8) was 100% and 30%, respectively for archived samples. Therefore, it is recommended to use fresh tissues for Microarray analysis.