Detection of HER2+ Breast Cancer Cells using Bioinspired DNA-Based Signal Amplification

DNA framework signal amplification platform-based high-throughput systemic immune monitoring

Systemic immune monitoring is a crucial clinical tool for disease early diagnosis, prognosis and treatment planning by quantitative analysis of immune cells. However, conventional immune monitoring using flow cytometry faces huge challenges in large-scale sample testing, especially in mass health screenings, because of time-consuming, technical-sensitive and high-cost features. However, the lack of high-performance detection platforms hinders the development of high-throughput immune monitoring technology. To address this bottleneck, we constructed a generally applicable DNA framework signal amplification platform (DSAP) based on post-systematic evolution of ligands by exponential enrichment and DNA tetrahedral framework-structured probe design to achieve high-sensitive detection for diverse immune cells, including CD4+, CD8+ T-lymphocytes, and monocytes (down to 1/100 μl). Based on this advanced detection platform, we present a novel high-throughput immune-cell phenotyping system, DSAP, achieving 30-min one-step immune-cell phenotyping without cell washing and subset analysis and showing comparable accuracy with flow cytometry while significantly reducing detection time and cost. As a proof-of-concept, DSAP demonstrates excellent diagnostic accuracy in immunodeficiency staging for 107 HIV patients (AUC > 0.97) within 30 min, which can be applied in HIV infection monitoring and screening. Therefore, we initially introduced promising DSAP to achieve high-throughput immune monitoring and open robust routes for point-of-care device development.

Polymerase-Driven Logic Signal Amplification for the Detection of Small Extracellular Vesicle Surface Proteins and the Identification of Breast Cancer

Small extracellular vesicles (sEVs) derived from tumors contain a vast amount of cellular information and are regarded as a potential diagnostic biomarker for noninvasive cancer diagnosis. Nevertheless, it remains challenging to accurately measure sEVs from clinical samples due to the low abundance of these vesicles as well as their phenotypic heterogeneity. Herein, a polymerase-driven logic signal amplification system (PLSAS) was developed for the high-sensitivity detection of sEV surface proteins and breast cancer (BC) identification. Aptamers were introduced to serve as sensing modules to specifically recognize target proteins. By changing the input DNA sequences, two polymerase-driven primer exchange reaction systems were rationally designed for DNA logic computing. This allows for autonomous targeting of a limited number of targets using "OR" and "AND" logic, leading to a significant increase in fluorescence signals and enabling the specific and ultrasensitive detection of sEV surface proteins. In this work, we investigated surface proteins of mucin 1 (MUC1) and the epithelial cell adhesion molecule (EpCAM) as model proteins. When MUC1 or EpCAM proteins were used as single signal input in the "OR" DNA logic system, the detection limit of sEVs was 24 or 58 particles/μL, respectively. And MUC1 and EpCAM proteins of sEVs can be simultaneously detected in the AND logic method, which can significantly reduce the effect of phenotypic heterogeneity of sEVs to distinguish the source of sEVs derived from various mammary cell lines, such as MCF-7, MDA MB 231, SKBR3, and MCF-10A. The approach has achieved high discrimination in serologically tested positive BC samples (AUC 98.1%) and holds significant potential in advancing the early diagnosis and prognostic assessments of BC.

Impact of Nanomedicine in Women's Metastatic Breast Cancer

Metastatic breast cancer is responsible for 90% of mortalities among women suffering from various types of breast cancers. Traditional cancer treatments such as chemotherapy and radiation therapy can cause significant side effects and may not be effective in many cases. However, recent advances in nanomedicine have shown great promise in the treatment of metastatic breast cancer. For example, nanomedicine demonstrated robust capacity in detection of metastatic cancers at early stages (i.e., before the metastatic cells leave the initial tumor site), which gives clinicians a timely option to change their treatment process (for example, instead of endocrine therapy they may use chemotherapy). Here recent advances in nanomedicine technology in the identification and treatment of metastatic breast cancers are reviewed.

A novel electrochemical biosensor based on AMNFs@ZIF-67 nano composite material for ultrasensitive detection of HER2

Antimonene (AMNFs) is a new kind of sp²-bonded honeycomb lattice two-dimensional material with strong rod-rail coupling, stability and hydrophilicity. Compared with graphene, antimonene has better sensitivity in DNA molecular sensing. We developed a suitable biosensor-Cd²⁺-aptamer@AMNFs@ZIF-67 nanocomposite for HER2 biomarker detection. Two-dimensional antimonene can be grown on the surface of ZIF-67 to enhance stability and biocompatibility. The aptamer chain can also be adsorbed on the surface of antimonene, and the complexes of the aptamer and the marker can be detached analytically after targeting the biomarker. The detection limit (LOD) was 4.853 fg/mL within 60 min, the detection range was 0-1000 pg/mL, and the LOD was lower than the existing HER2 aptamer biosensors. The results show that the biosensor has certain applicability and potential, and is expected to be a powerful tool for breast cancer diagnosis in the future.

Ultrasensitive and multiplexed miRNA detection system with DNA-PAINT

MiRNAs hold great potential as biomarkers for the early detection and monitoring of diseases based on their differential expression profiles. Therefore, the sensitive, specific and accurate detection of miRNAs represents an emerging new tool to improve diagnosis and treatment of several diseases, cancer in particular. DNA origami-based miRNA detection is particularly advantageous as it allows to incorporate multiple attachment sites to capture different target miRNAs at the nanoscale. In this work, we present a DNA origami nanoarray system providing distance-dependent recognition of miRNAs by applying super-resolution microscopy technique; DNA-PAINT (point accumulation for imaging in nanoscale topography). The sensor can detect up to 4 miRNAs either separately or in combination based on the relative distance to the boundary markers on the structure using a single imager strand. The detection is highly sensitive, with a limit of detection down to the low femtomolar range (11 fM - 388 fM) and has a large dynamic range up to 10 nM without need for amplification. Moreover, our detection system can discriminate single base mismatches with low false positive rates. Using our strategy, we demonstrate the detection of endogenous miRNAs from cell extracts of cancer cell lines and plasma from breast cancer patients. Overall, we developed an ultrasensitive and amplification-free, DNA-PAINT imaging-based miRNA detection method using DNA origami nanoarray system for the detection of breast-cancer associated miRNAs which potentially provides a sensitive and accurate alternative to the current multiplexed diagnostic technologies.

An ultrasensitive dual-signal ratio electrochemical aptamer biosensor for the detection of HER2

Electrochemical ratiometric biosensors have received attention from researchers because of their self-calibration capability, which can improve the accuracy of detection. In the present study, a ratiometric dual signal electrochemical aptamer biosensor based on ZIF-67 @polydopamine (PDA) nanocomposite and Cu/UiO-66 @ 3, 3', 5, 5'-tetramethylbenzidine (TMB) nanocomposite was fabricated for the detection of breast cancer biomarker- human epidermal growth factor receptor 2 (HER2). PDA was chosen as the electroactive material with electrochemical redox activity and ZIF-67 with a high specific surface area, forming the ZIF-67 @PDA+Apt as the nanoprobe for capturing HER2 in this paper. Cu/UiO-66 is a bimetallic compound with high stability, specific surface area, and strong adsorption onto aptamer chains, and the Cu/UiO-66 @TMB+Apt nanocomposite was used as a probe for signal labeling. In the presence of HER2, the capture of HER2 by the ZIF-67 @PDA+Apt probe results in a weakening of the conductivity of the electrode, however, by attenuating the electrochemical signal from the PDA, altering the probe-Cu/UiO-66 @TMB+Apt signaling will result in the enhancement of the TMB electrochemical signal. With a sensitive detection of HER2 biomarkers in as little as 30 min with the detection range of 0.75-40 pg/mL and a limit of detection as low as 44.8 fg/mL. Dual signal ratio biosensors have a low limit of detection, short detection time, which can accurately detect targets in complex biological samples, which has important theoretical importance.

Nucleic acid and nanomaterial-assisted signal-amplified strategies in fluorescent analysis of circulating tumor cells and small extracellular vesicles

As two main types of liquid biopsy markers, both circulating tumor cells (CTCs) and small extracellular vesicles (sEVs) play important roles in the diagnosis and prognosis of cancers. CTCs are malignant cells that detach from the original tumor tissue and enter the circulation of body fluids. sEVs are nanoscale vesicles secreted by normal cells or pathological cells. However, CTCs and sEVs in body fluids are scarce, leading to great difficulties in the accurate analysis of related diseases. For the sensitive detection of CTCs and sEVs in body fluids, various types of nucleic acid and nanomaterial-assisted signal amplification strategies have been developed. In this review, we summarize the recent advances in fluorescent detection of CTCs and sEVs in liquid biopsy based on nucleic acid and nanomaterial-assisted signal amplification strategies. We also discuss their advantages, challenges, and future prospects.

Nucleic Acid Tests for Clinical Translation

Nucleic acids, including deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are natural biopolymers composed of nucleotides that store, transmit, and express genetic information. Overexpressed or underexpressed as well as mutated nucleic acids have been implicated in many diseases. Therefore, nucleic acid tests (NATs) are extremely important. Inspired by intracellular DNA replication and RNA transcription, in vitro NATs have been extensively developed to improve the detection specificity, sensitivity, and simplicity. The principles of NATs can be in general classified into three categories: nucleic acid hybridization, thermal-cycle or isothermal amplification, and signal amplification. Driven by pressing needs in clinical diagnosis and prevention of infectious diseases, NATs have evolved to be a rapidly advancing field. During the past ten years, an explosive increase of research interest in both basic research and clinical translation has been witnessed. In this review, we aim to provide comprehensive coverage of the progress to analyze nucleic acids, use nucleic acids as recognition probes, construct detection devices based on nucleic acids, and utilize nucleic acids in clinical diagnosis and other important fields. We also discuss the new frontiers in the field and the challenges to be addressed.

Detection of HER2+ Breast Cancer Cells using Bioinspired DNA-Based Signal Amplification

Circulating tumor cells (CTC) are promising biomarkers for metastatic cancer detection and monitoring progression. However, detection of CTCs remains challenging due to their low frequency and heterogeneity. Herein, we report a bioinspired approach to detect individual cancer cells, based on a signal amplification cascade using a programmable DNA hybridization chain reaction (HCR) circuit. We applied this approach to detect HER2⁺ cancer cells using the anti‐HER2 antibody (trastuzumab) coupled to initiator DNA eliciting a HCR cascade that leads to a fluorescent signal at the cell surface. At 4 °C, this HCR detection scheme resulted in highly efficient, specific and sensitive signal amplification of the DNA hairpins specifically on the membrane of the HER2⁺ cells in a background of HER2⁻ cells and peripheral blood leukocytes, which remained almost non‐fluorescent. The results indicate that this system offers a new strategy that may be further developed toward an in vitro diagnostic platform for the sensitive and efficient detection of CTC.