Studies On The SOX4 Gene Mutation Of Lung Cancer Tissue

The SOX gene family is characterized by the presence of a HMG domain involved in various developmental processes. The encoded proteins are capable of binding to DNA in a sequence-specific manner. In human, the deletion or mutation of SOX proteins results in developmental defects and congenital disease. It has been shown that mutation in the human SOX9 gene cause campomelic dysphasia (CD) and autonomic sex reversal, the mutation of SOX10 gene cause Warrensburg syndrome (WS), and so on. The specimen DNA is important for the research of reviewing large quantity cases in medicine. This paper reports different pretreatment methods of paraffin embedded lung cancer tissues before DNA extraction. After taking off paraffin wax with Xylene , first infuse them into PBS buffer for 4-8 hours in water bath, the temperature was 60℃, then handle them with different concentration of alcohol. The result showed that this method can acquire long DNA fragments, and the PBS buffer at pH 7.5-8.5 gave higher yields of DNA. Lung cancer is a familiar malignancy currently, the nosogenesis is very complex. The studies indicated that the SOX4 gene may be involved in the human lung carcinogenesis. Using PCR-SSCP and PCR product direct sequencing techniques, we analysed the ORF region of SOX4 gene encoding in 15 lung cancer tissues and 8 normal controls. We found point mutation at position 461,679,687,698,712,713bp in the SOX4 gene in 5 cases, but it was not found in normal controls. All of 5 mutated cases ,including 4 cases of G/C/T/C to C/G/C/T at 692,698,713,716bp, 2 cases of G/G to A/T at 679,712b,1 case of C to A at 461bp and 1 case of G to C at 687bp. We also found the mutations were located in HMG-box except the position of 461bp, and the amino acid mutations were all located in HMG-box. It suggests that the SOX4 gene mutation may be associated with the carcinogenesis of the lung cancer. Our studies first reports the SOX4 gene mutation of the lung cancer tissue, and also provides molecular data for the study of the relations between the mutation of SOX gene and disease occurrence.