Imaging of Cancer Cells and Dictated Cytotoxicity Using Aptamer‐Guided Hybridization Chain Reaction (HCR)‐Generated G‐Quadruplex Chains

Abstract

DNA nanotechnology provides powerful tools for developing cancer theranostics. Here we introduce the autonomous surface‐nucleolin‐guided HCR that leads to the polymerization of G‐quadruplex polymer chains, in which the ZnII‐protoporphyrin IX is intercalated. We demonstrate that MDA‐MB‐231 (Triple Negative Breast Cancer cells, TNBC) with overexpressed surface nucleolin were able to induce HCR leading to the formation of the ZnIIPPIX‐loaded G‐quadruplex polymer chains, while the M10 epithelial breast cells served as control. The ZnIIPPIX‐loaded nanowires allow the selective imaging of TNBC, and their permeation into the TNBC leads to selective cytotoxicity and guided photodynamic therapy toward the cancer cells due to structural perturbation of the membranes. The aptamer‐guided HCR‐generated G‐quadruplex polymer chains may serve as a versatile tool to target TNBC featuring poor prognosis and high pathological risk of recurrence, thus offering a promising theranostic platform.

Monitoring and modulating a catalytic hybridization circuit for self-adaptive bioorthogonal DNA assembly

“…In contrast, nearly no detectable fluorescence response appeared in normal human lung fibroblast (MRC-5) and MCF-10A cells, implying a relatively higher expression of miR-21 in tumour cells than in normal cells, which was consistent with previous research. [41][42][43][44][45] Meanwhile, the performance of our designed LCC system to distinguish the varied miR-21 expression levels in different cells was furtherly verified by a quantitative flow cytometry assay (Figure 6B). In addition, the shortest characteristic diffusion time was exhibited in MCF-10A and MRC-5 cells, followed by HeLa cells, while the slowest molecular diffusion signal was shown in MCF-7 cells (Figure 6C).…”

“…In contrast, nearly no detectable uorescence response appeared in normal human lung broblast (MRC-5) and MCF-10A cells, implying a relatively higher expression of miR-21 in tumour cells than that in normal cells, which was consistent with previous research. [41][42][43][44][45] Meanwhile, the performance of our designed LCC system to distinguish the varied miR-21 expression levels in different cells was further veried by a quantitative ow cytometry assay (Fig. 6B).…”

Sensitive fluorescence assay of chloramphenicol coupled with two-level isothermal amplification using a self-powered catalyzed hairpin assembly and entropy-driven circuit

“…21 To achieve better sensitivity, some isothermal amplication techniques have been coupled with aptamers, such as the hybridization chain reaction (HCR), rolling circle amplication (RCA), catalytic hairpin assembly (CHA) and entropy-driven circuit (EDC). [22][23][24][25][26][27] Isothermal amplication reactions of nucleic acids have emerged as promising alternatives for signal amplication, which can rapidly and efficiently amplify signals with constant temperature. 28 So far, they have been widely used for the bio-sensing of various targets such as ions, small molecules, DNA, RNA, proteins and cells.…”

Fluorescent Features and Applicable Biosensing of a Core–Shell Ag Nanocluster Shielded by a DNA Tetrahedral Nanocage

“…The G12 motif was able to fold into a G-quadruplex (G4) conformation and form a hemin/G4 (hG4) conjugate in the presence of 20 mM K + , 40 mM Na + (Figure S11A), and 1.0 μM hemin. This was verified by the orthogonal fluorescence signals, CD spectra, and UV−vis absorption spectra of hG4 (Figure S11B−D), 37 respectively. The immobilization of GS in uTDC directed the creation of a biosensing platform in a signal "on− off−on" fashion.…”