Multi-parameter Inputted Logic-Gating on Aptamer-Encoded Extracellular Vesicles for Colorectal Cancer Diagnosis

Extracellular vesicles (EVs) have emerged as a potential biomarker in liquid biopsy. However, cancer heterogeneity poses significant challenge to precise molecular diagnosis based on single-parameter input. Hence, strategies for analyzing multiple inputs with molecular computing were developed with the aim of improving diagnostic accuracy in liquid biopsy. In the present study, based on the surface of aptamer-encoded EVs, three toe-hold extended DNA aptamers served as specific inputs to perform AND-logic-gating to distinguish between healthy and cancerous EVs. In addition, this strategy has been successfully employed to analyze circulating EVs in clinical samples from colorectal cancer patients and healthy donors. The developed method has a promising future in the analysis of multiplex EV membrane proteins and the identification of early cancer

Conjugating Aptamer and Mitomycin C with Reductant-Responsive Linker Leading to Synergistically Enhanced Anticancer Effect

Mitomycin C (MMC) has been using for the treatment of a variety of digestive tract cancers. However, its nonspecific DNA-alkylating ability usually causes severe side effects, thus largely limiting its clinical applications. The utilization of an efficient active targeted drug delivery technique would address this issue. Accordingly, we report the design and development of aptamer–mitomycin C conjugates that use different cross-linking chemistry. The targeted delivery ability and cytotoxicity of these conjugates were carefully studied. It is worth noting that a linker-dependent cytotoxicity effect was observed for these conjugates. The use of a reductant-sensitive disulfide bond cross-linking strategy resulted in significantly enhanced cytotoxicity of MMC against the target cancer cell lines. Importantly, this cytotoxicity enhancement was suited to different types of aptamers, demonstrating the success of our design. Mechanistic studies of the enhanced cytotoxicity effect indicated that the target recognition, specific binding, and receptor-mediated internalization of aptamer were also critical for the observed effect

The interaction energy between PA and <i>β</i>-CD calculated with amber 11 program.

The interaction energy between PA and β-CD calculated with amber 11 program.</p

Phase solubility diagram of PA and <i>β</i>-CD at 25, 35°C (n = 3).

<p>Phase solubility diagram of PA and <i>β</i>-CD at 25, 35°C (n = 3).</p

Biocompatible Surface-Coated Probe for <i>in Vivo</i>, <i>in Situ</i>, and Microscale Lipidomics of Small Biological Organisms and Cells Using Mass Spectrometry

Lipidomics is a significant way to understand the structural and functional roles that lipids play in biological systems. Although many mass spectrometry (MS)-based lipidomics strategies have recently achieve remarkable results, <i>in vivo</i>, <i>in situ</i>, and microscale lipidomics for small biological organisms and cells have not yet been obtained. In this article, we report a novel lipidomics methodology for <i>in vivo</i>, <i>in situ</i>, and microscale investigation of small biological organisms and cells using biocompatible surface-coated probe nanoelectrospray ionization mass spectrometry (BSCP-nanoESI-MS). A novel biocompatible surface-coated solid-phase microextration (SPME) probe is prepared, which possesses a probe-end diameter of less than 5 μm and shows excellent enrichment capacity toward lipid species. <i>In vivo</i> extraction of living biological organisms (e.g., zebrafishes), <i>in situ</i> sampling a precise position of small organisms (e.g., <i>Daphnia magna</i>), and even microscale analysis of single eukaryotic cells (e.g., HepG2) are easily achieved by the SPME probe. After extraction, the loaded SPME probe is directly applied for nanoESI-MS analysis, and a high-resolution mass spectrometer is employed for recording spectra and identifying lipid species. Compared with the conventional direct infusion shotgun MS lipidomics, our proposed methodology shows a similar result of lipid profiles but with simpler sample pretreatment, less sample consumption, and shorter analytical times. Lipidomics of zebrafish, <i>Daphnia magna</i>, and HepG2 cell populations were investigated by our proposed BSCP-nanoESI-MS methodology, and abundant lipid compositions were detected and identified and biomarkers were obtained via multivariate statistical analysis

Lowest energy PA-<i>β</i>-CD docked complex.

<p>(A) Stick model. (B) The optimized model. Yellow stick represents <i>β</i>-CD and grey small molecule represents PA.</p

Degradation profiles of PA-CD inclusion complex (a, c, e) and PA (b, d, f).

<p>Thermal stability (a, b), humidity stability (c,d), and photostability (e,f).</p

Chemical structures of (A) PA and (B) <i>β</i>-cyclodextrin.

<p>Chemical structures of (A) PA and (B) <i>β</i>-cyclodextrin.</p