Subtractive Cell-SELEX Selection of DNA Aptamers Binding Specifically and Selectively to Hepatocellular Carcinoma Cells with High Metastatic Potential

Abstract

Relapse and metastasis are two key risk factors of hepatocellular carcinoma (HCC) prognosis; thus, it is emergent to develop an early and accurate detection method for prognostic evaluation of HCC after surgery. In this study, we sought to acquire oligonucleotide DNA aptamers that specifically bind to HCC cells with high metastatic potential. Two HCC cell lines derived from the same genetic background but with different metastatic potential were employed: MHCC97L (low metastatic properties) as subtractive targets and HCCLM9 (high metastatic properties) as screening targets. To mimic a fluid combining environment, initial DNA aptamers library was firstly labelled with magnetic nanoparticles using biotin-streptavidin system and then applied for aptamers selection. Through 10-round selection with subtractive Cell-SELEX, six aptamers, LY-1, LY-13, LY-46, LY-32, LY-27/45, and LY-7/43, display high affinity to HCCLM9 cells and do not bind to MHCC97L cells, as well as other tumor cell lines, including breast cancer, lung cancer, colon adenocarcinoma, gastric cancer, and cervical cancer, suggesting high specificity for HCCLM9 cells. Thus, the aptamers generated here will provide solid basis for identifying new diagnostic targets to detect HCC metastasis and also may provide valuable clues for developing new targeted therapeutics.

Current Advances in Aptamers for Cancer Diagnosis and Therapy

“…For better specificity to highly metastatic cells, Chen et al developed aptamers against hepatocellular carcinoma cells from high metastatic (HCCLM9) and low metastatic (MHCC97L) cell lines derived from the same genetic background. These aptamers were found to have high specificity to the high metastatic line but did not bind to any of the other cell lines tested suggesting high specificity to HCCLM9 [ 123 , 124 ].…”

Aptamers as Diagnostic Tools in Cancer

“…Over the past two decades, cell-SELEX technology has been used for the selection of specific aptamers with diagnostic and therapeutic purposes over a wide variety of cell surface targets, particularly for tumor cells. Multiple groups have reported the discovery of new important biomarkers in different types of cancer and other diseases through the use of cell-SELEX [ 18 , 33 , 34 , 35 ].…”

The Potential of Aptamer-Mediated Liquid Biopsy for Early Detection of Cancer

“…Currently, most cancers lack effective non-invasive screening tests and are therefore detected too late. Liquid biopsy is a promising tool for the early detection of cancer [ 3 , 4 ], and significant advancement of the technique shows potential as a diagnostic tool for a variety of cancer types, including melanoma [ 5 , 6 , 7 , 8 ], breast [ 9 , 10 , 11 ], colorectal [ 12 , 13 , 14 ], lung [ 15 ], liver [ 16 , 17 , 18 ], ovarian [ 19 ], pancreatic [ 20 ], and gastric cancers [ 21 ]. The most common analytical targets of liquid biopsy are circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), microRNA, and extracellular vesicles (EVs) [ 22 , 23 , 24 , 25 , 26 ].…”