Lung cancer is the first malignant tumor with morbidity and mortality in the world. To identify a novel lung cancer biomarker facilitating early detection lung cancer, we had obtained a nucleic acid aptamer (Apt-5) that specifically recognized lung cancer serum. An affinity purification experiment by using magnetic nanoparticles was used to pull down the target proteins, protein CLEC3B was subsequently identified as the target of the aptamer Apt-5 by MS analysis. The aptamer Apt-5 displayed high affinity to the CLEC3B protein with a dissociation constant (KD) of 23.9 � 5.5 nM by SPR. The specificity and selectivity of the CLEC3B protein with the aptamer Apt-5 were verified by EMSA. It was further confirmed by ELISA experiments that the average concentration of CLEC3B in lung cancer serum was higher than that in healthy human serum (3.272 � 0.1732 ng/mL vs. 2.104 � 0.1174 ng/mL, P < 0.001.). Moreover, the sensitivity and specificity of ELISA assay in this study are 90 % and 80 %, respectively. So the protein CLEC3B might serve as a potential lung cancer biomarker for early diagnosis and therapy.

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.

No abstract

No abstract