In Vivo Cancer Cells Elimination Guided by Aptamer-Functionalized Gold-Coated Magnetic Nanoparticles and Controlled with Low Frequency Alternating Magnetic Field

Biomedical applications of magnetic nanoparticles in a magnetic field have exceeded many expectations in cancer therapy. Magnetic nanoparticles are effective heat mediators, drug nanocarriers, and contrast agents; various strategies have been suggested to selectively target tumor cancer cells but not healthy cells. Our study presents magnetodynamic nanotherapy utilizing DNA aptamer-functionalized 50 nm gold-coated magnetic nanoparticles exposed to a low frequency alternating magnetic field for precise elimination of tumor cells in vivo. The cell specific DNA aptamer AS-14 binds to fibronectin protein in Ehrlich carcinoma and delivers gold-coated magnetic nanoparticles to a mouse tumor. An alternating magnetic field of 50 Hz causesthe nanoparticles to oscillate and pull fibronectin and integrins on the surface of the cell membrane resulting in massive cell apoptosis followed by necrosis without heating the tumor, adjacent healthy cells and tissues. The aptamer-guided nanoparticles and the low frequency alternating magnetic field demonstrates a unique technology of a non-invasive nanoscalpel for precise cancer surgery at a single cell level

In Vivo Cancer Cells Elimination Guided by Aptamer-Functionalized Gold-Coated Magnetic Nanoparticles and Controlled with Low Frequency Alternating Magnetic Field

Biomedical applications of magnetic nanoparticles in a magnetic field have exceeded many expectations in cancer therapy. Magnetic nanoparticles are effective heat mediators, drug nanocarriers, and contrast agents; various strategies have been suggested to selectively target tumor cancer cells but not healthy cells. Our study presents magnetodynamic nanotherapy utilizing DNA aptamer-functionalized 50 nm gold-coated magnetic nanoparticles exposed to a low frequency alternating magnetic field for precise elimination of tumor cells in vivo. The cell specific DNA aptamer AS-14 binds to fibronectin protein in Ehrlich carcinoma and delivers gold-coated magnetic nanoparticles to a mouse tumor. An alternating magnetic field of 50 Hz causesthe nanoparticles to oscillate and pull fibronectin and integrins on the surface of the cell membrane resulting in massive cell apoptosis followed by necrosis without heating the tumor, adjacent healthy cells and tissues. The aptamer-guided nanoparticles and the low frequency alternating magnetic field demonstrates a unique technology of a non-invasive nanoscalpel for precise cancer surgery at a single cell level

Development of DNA Aptamers to Native EpCAM for Isolation of Lung Circulating Tumor Cells from Human Blood

We selected DNA aptamers to the epithelial cell adhesion molecule (EpCAM) expressed on primary lung cancer cells isolated from the tumors of patients with non-small cell lung cancer using competitive displacement of aptamers from EpCAM by a corresponding antibody. The resulting aptamers clones showed good nanomolar affinity to EpCAM-positive lung cancer cells. Confocal microscopy imaging and spectral profiling of lung cancer tissues confirmed the same protein target for the aptamers and anti-EpCAM antibodies. Furthermore, the resulted aptamers were successfully applied for isolation and detection of circulating tumor cells in clinical samples of peripheral blood of lung cancer patients

Aptamer-Targeted Plasmonic Photothermal Therapy of Cancer

Novel nanoscale bioconjugates combining unique plasmonic photothermal properties of gold nanoparticles (AuNPs) with targeted delivery using cell-specific DNA aptamers have a tremendous potential for medical diagnostics and therapy of many cell-based diseases. In this study, we demonstrate the high anti-cancer activity of aptamer-conjugated, 37-nm spherical gold nanoparticles toward Ehrlich carcinoma in tumor-bearing mice after photothermal treatment. The synthetic anti-tumor aptamers bring the nanoparticles precisely to the desired cells and selectively eliminate cancer cells after the subsequent laser treatment. To prove tumor eradication, we used positron emission tomography (PET) utilizing radioactive glucose and computer tomography, followed by histological analysis of cancer tissue. Three injections of aptamer-conjugated AuNPs and 5 min of laser irradiations are enough to make the tumor undetectable by PET. Histological analysis proves PET results and shows lower damage of healthy tissue in addition to a higher treatment efficiency and selectivity of the gold nanoparticles functionalized with aptamers in comparison to control experiments using free unconjugated nanoparticles

DNA Aptamers for the Characterization of Histological Structure of Lung Adenocarcinoma

Nucleic acid aptamers are becoming popular as molecular probes for identification and imaging pathology and, at the same time, as a convenient platform for targeted therapy. Recent studies have shown that aptamers may be effectively used for tumor characterization and as commercially available monoclonal antibodies. Here we present three DNA aptamers binding to whole transformed lung cancer tissues, including tumor cells, connective tissues, and blood vessels. Protein targets have been revealed using affinity purification followed by mass spectrometry analyses, and they have been validated using a panel of correspondent antibodies and 3D imaging of tumor tissues. Each of the proteins targeted by the aptamers is involved in cancer progression and most of them are crucial for lung adenocarcinoma. We propose the use of these aptamers in aptahistochemistry for the characterization of the histological structure of lung adenocarcinoma. The value of the presented aptamers is their application together or separately for indicating the spread of neoplastic transformation, for complex differential diagnostics, and for targeted therapy of the tumor itself as well as all transformed structures of the adjacent tissues. Moreover, it has been demonstrated that these aptamers could be used for intraoperative tumor visualization and margin assessment. Keywords: DNA-aptamer, lung adenocarcinoma, histological structur