Screening and Specificity Analysis of Aptamer in Infiltrating Ductal Carcinoma of Breast

Breast cancer is a common malignant tumor disease in women, and early diagnosis has a better preventive effect on cancer. Aptamers, which are mainly screened by the exponential enrichment ligand phylogenetic technique, play an important role in the early diagnosis of cancer as early diagnostic molecules. In this study, aptamers identified specifically infiltrating ductal carcinoma of breast were obtained and their specificity was investigated. The aptamers of invasive ductal carcinoma of breast were screened based on Serum‐SELEX (Ser‐SELEX) technology, and sequences that specific binding were obtained by high‐throughput sequencing. The secondary structure of the aptamers was predicted by online software, the affinity and specificity of the aptamers were determined by q‐PCR and ELASA. After 13 rounds of screening, the aptamer IDC31 was obtained, and its secondary structure was predicted to have a stem ring structure. The q‐PCR results showed that the aptamer IDC31 had strong affinity and specificity for infiltrating ductal carcinoma of breast, and the dissociation constants were within the nanomolar range. The ELASA test showed that IDC31 had great specificity for breast invasive ductal carcinoma, and the detection rate was over 80 %. Therefore, the aptamer IDC31 could be used as an early diagnosis tool for breast invasive ductal carcinoma, which provided a possibility for the early diagnosis of breast invasive ductal carcinoma. We used Serum‐SELEX technology to screen aptamer of IDC serum, and finally obtained the IDC31 with high specificity and affinity. Through serum and ELASA method monitoring, it was found that the aptamer had a strong specificity to IDC serum. In conclusion, IDC31 can be used as a molecular probe for the early diagnosis of IDC patients, providing a possibility for the early diagnosis of IDC.