RESUMO
The hybridization chain reaction (HCR), as one of the nucleic acid amplification technologies, is combined with fluorescence signal output with excellent sensitivity, simplicity, and stability. However, current HCR-based fluorescence sensing methods still have some defects such as the blocking effect of the HCR combination with fluorophores and the aggregation-caused quenching (ACQ) phenomenon of traditional fluorophores. Herein, a triplex DNA-based aggregation-induced emission probe (AIE-P) was designed as the fluorescent signal transduction, which is able to provide a new platform for HCR-based sensing assay. The AIE-P was synthesized by attaching the AIE fluorophores to terminus of the oligonucleotide through amido bond, and captured the products of HCR to form triplex DNA. In this case, the AIE fluorophores were located in close proximity to generate fluorescence. This assay provided turn-on fluorescence efficiency with a high signal-to-noise ratio and excellent amplification capability to solve the shortcoming of HCR-based fluorescence sensing methods. It enabled sensitive detection of Vibrio parahaemolyticus in the range of 102-106 CFU mL-1, and with a low limit of detection down to 39 CFU mL-1. In addition, this assay expressed good specificity and practicability. The triplex DNA-based AIE probe forms a universal molecular tool for developing HCR-based fluorescence sensing methods.
Assuntos
Técnicas Biossensoriais , DNA , DNA/genética , DNA/química , Hibridização de Ácido Nucleico/métodos , Corantes Fluorescentes/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas Biossensoriais/métodos , Limite de DetecçãoRESUMO
Cancer stem cells (CSCs) and epithelialmesenchymal transition (EMT) are critical factors contributing to tumor metastasis and recurrence. The BMI1 protooncogene (Bmi1) promotes the development and progression of hematologic malignancies and of several types of solid tumors. The aim of the present study was to explore the mechanism by which Bmi1 may promote invasion and migration of hepatocellular carcinoma Hep G2 cells. CD133 antigen is a transmembrane glycoprotein and regarded as a cancer stem cells marker in hepatocellular carcinoma. CD133+Hep G2 cells were enriched by magneticactivated cell sorting and exhibited greater viability compared with CD133Hep G2 cells, as measured by Cell Counting kit8 assay. Then, Bmi1 was overexpressed in CD133+Hep G2 cells by transfection with the Bmi1/pcDNA3.1(+) expression plasmid, and overexpression was confirmed by reversetranscriptionpolymerase chain reaction and western blotting. Overexpression of Bmi1in CD133+Hep G2 cells resulted in the downregulation of Ecadherin and upregulation of Vimentin at the protein level. The invasion and migration abilities of CD133+Hep G2 cells were increased in the Bmi1/pcDNA3.1(+)transfected group, as measured by Transwell invasion and wound healing assays, respectively. In conclusion, Bmi1 promoted invasion and migration of CD133+Hep G2 cells most likely through inducing EMT. The present findings may offer a potential novel target for the development of hepatocellular carcinoma therapies.