A DNA aptamer recognizing MMP14 for in�vivo and in�vitro imaging identified by cell‑SELEX

Abstract

A key challenge for the management of various types of cancer, including pancreatic cancer and hepatocellular carcinoma, is accurate diagnosis at an early stage. Matrix metalloproteinase 14 (MMP14) is overexpressed in numerous types of cancer and is associated with poor prognosis. Therefore, MMP14-specific imaging probes have potential use in the diagnosis of MMP14-positive cancer. Aptamers are short oligonucleotide sequences that can bind to molecular targets with a high specificity and affinity. Aptamers are typically obtained from an in vitro library; this process is usually termed systematic evolution of ligands by exponential enrichment (SELEX). In the present study, a DNA aptamer targeting MMP14 was obtained by cell-SELEX and termed M17, which specifically recognizes MMP14-positive cells. Aptamer M17 selectively binds to membrane proteins of MMP14-transfected 293T cells (Kd, 4.98±1.26 nM). Pancreatic cancer cell imaging suggested that aptamer M17 can bind to the cell membranes of two pancreatic cancer cell lines (MIA PaCa-2 and PANC-1). In vivo tumor imaging demonstrated that the targeting recognition of MIA PaCa-2 tumor cells in mice could be visualized using Cy5-labeled aptamer M17. Aptamer M17-conjugated polyethylene glycol-Fe3O4 can specifically bind to MIA PaCa-2 and PANC-1 cells, and reduce MRI T2-weighted imaging signal intensity. The DNA aptamer M17 has the advantages of simplicity of synthesis, small size, low immunogenicity, high penetrability and high affinity. Therefore, aptamer M17 is a potential molecular probe for the diagnosis and treatment of MMP14-positive cancer.

Advances in Medical Imaging: Aptamer- and Peptide-Targeted MRI and CT Contrast Agents

“…The Huan group was able to select a DNA aptamer, M17, using MMP14-transfected 293T cells. 24 In vivo fluorescence imaging, utilizing MIA PaCa-2 tumor-bearing BALB/c mice, was used to confirm that M17 is able to specifically recognize MMP14-positive cells. They subsequently utilized M17 in surface functionalization of magnetic nanoparticles (Fe 3 O 4 ) for MRI imaging.…”

Aptamers: a novel targeted theranostic platform for pancreatic ductal adenocarcinoma

“…Recently, a novel matrix metalloproteinase 14 (MMP14)-targeted aptamer (M17) conjugated with polyethylene glycol-Fe 3 O 4 was synthesized. This molecule can specifically bind to pancreatic cancer cells in vitro and hereby reduce MRI T2-weighted imaging signal intensity [ 51 ]. As a result, this novel molecular-targeted MRI approach bears potential for PDAC diagnostics.…”

Development and characterization of aptamer-conjugated imaging tools for diagnostic applications

“…These advantages are based on their small size, non-immunogenic nature, tight and specific target binding, and ease of synthesis and handling. [88][89][90][91][92] As above, Table 1.4 highlights some of the important aspects that were highlighted in the research described in this section. These can be used as recommendations for important elements of testing in the future development of aptamer-targeted contrast agents.…”

“…The Huan group was able to select a DNA aptamer, M17, using MMP14-transfected 293T cells. 90 In vivo fluorescence imaging, utilizing MIA PaCa-2 tumor-bearing BALB/c mice, was used to confirm that M17 is able to specifically recognize MMP14-positive cells. They subsequently utilized M17 in surface-functionalization of magnetic nanoparticles (Fe3O4) for MRI imaging.…”

“…Overall, targeted delivery resulted in high specificity and high affinity of SPIONs towards MMP14 marker, confirming that this formulation is a promising targeting agent with potential to be used for targeted diagnosis and treatment of MMP14-positive cancers. 90 It is commonly accepted that early cancer detection is crucial for optimized therapeutic response. While hepatocellular carcinoma (HCC) is readily diagnosed in its late stage with the help of MRI and CT imaging, detection of lesions smaller than 2 cm, associated with early stages of this cancer, is 47% or less.…”