Biosensor Design for the Detection of Circulating Tumor Cells Using the Quartz Crystal Resonator Technique.

A new mass-sensitive biosensing approach for detecting circulating tumor cells (CTCs) using a quartz crystal resonator (QCR) has been developed. A mathematical model was used to design a ring electrode-based QCR to eliminate the Gaussian spatial distribution of frequency response in the first harmonic mode, a characteristic of QCRs, without compromising the sensitivity of frequency response. An ink-dot method was used to validate the ring electrode fabricated based on our model. Furthermore, the ring electrode QCR was experimentally tested for its ability to capture circulating tumor cells, and the results were compared with a commercially available QCR with a keyhole electrode. An indirect method of surface immobilization technique was employed via modification of the SiO2 surface of the ring electrode using a silane, protein, and anti-EpCAM. The ring electrode successfully demonstrated eliminating the spatial nonuniformity of frequency response for three cancer cell lines, i.e., MCF-7, PANC-1, and PC-3, compared with the keyhole QCR, which showed nonuniform spatial response for the same cancer cell lines. These results are promising for developing QCR-based biosensors for the early detection of cancer cells, with the potential for point-of-care diagnosis for cancer screening.

Nanotechnology for ultrafast nucleic acid amplification

Nucleic acid detection has been one of the most valued tools in point-of-care diagnostics from life science, agriculture, food safety and environmental surveillance, because of its high sensitivity, great specificity and simple operation. Since polymerase chain reactions (PCR) were discovered, more and more researchers attach importance to exploring ultrafast nucleic acid amplification methods for further expediting the process of detection and curbing infectious diseases' high spread rate, especially after the coronavirus disease 2019 (COVID-19) worldwide pandemic event. Nowadays, nanotechnology as one of the most cut-ting-edge technologies has aroused growing attention. In this review, we describe new advances in na-notechnology research for ultrafast nucleic acid amplification. We have introduced commonly used nanotechnologies, namely nanofluidics, nanoporous materials, nanoparticles and so on. Recent advances in these nanotechnologies for ultrafast sample pretreatments, accelerated enzymatic amplification and rapid heating/cooling processes was summarized. Finally, challenges and perspectives for the future applications of ultrafast nucleic acid amplification are presented.(c) 2022 Elsevier Ltd. All rights reserved.

Nanotechnology Solution for Early Detection of Micrometastatic Prostate Cancer After Radical Prostatectomy

The overall objective of this research proposal is to conduct the initial development of a rapid circulating tumor cell-based blood test that can identify men with micrometastatic disease in order to facilitate patient selection for salvage radiotherapy. Aim 1 of this study was do perform a technical validation study and Aim 2 to embark upon testing of banked clinical specimens then to test the new assay in the setting of the NRG-GU-006 clinical trial (salvage radiotherapy /- apalutamide). In the first year of work we have begun a series of key technical validation studies while completing the sample collection from the now fully accrued NRG-GU-006 trial. Due to COVID-19 there were delays in progress but due to rapid clinical accrual and regearing of our studies, this effort is still on time.

Multimodal CTC detection using stem cell antigen-specific immunosilica particles and immunofluorescent quantum dots

Amid the COVID-19 pandemic, cancer continues to be the most devastating disease worldwide. Liquid biopsy of circulating tumor cells (CTCs) has recently become a painless and noninvasive tool for obtaining carcinoma cell samples for molecular profiling. Here, we report efficient detection and collection of cancer cells in blood samples by combining stem cell antigen (CD44)-specific immunosilica particles and immunofluorescent quantum dots with spectrally and temporally resolved single-photon counting. We accurately detect 1-10 cells among 100 cancer cells of the breast, lungs, or cervix in 1 mL blood samples. In addition, the bright and narrowband emission of CdSe/ZnS quantum dots enables temporally and spectrally resolved photon counting for multiplexed cancer cell detection. The cancer cell-specific and large immunosilica particles helped us collect the specific cells. We validate the detection efficiency and multimodality of this strategy by time-stamped and energy-dispersed single-photon counting of orange- and red-emitting quantum dots and green-fluorescing nuclei stained with Syto-13/25 dye. Thus, the present work highlights the prospects of multimodal CTC detection for noninvasive cancer screening and postsurgical or therapeutic follow-up.

The Breast Tumor Microenvironment: A Key Player in Metastatic Spread.

The tumor microenvironment plays a pivotal role in the tumorigenesis, progression, and metastatic spread of many cancers including breast. There is now increasing evidence to support the observations that a bidirectional interplay between breast cancer cells and stromal cells exists within the tumor and the tumor microenvironment both at the primary tumor site and at the metastatic site. This interaction occurs through direct cell to cell contact, or by the release of autocrine or paracrine factors which can activate pro-tumor signaling pathways and modulate tumor behavior. In this review, we will highlight recent advances in our current knowledge about the multiple interactions between breast cancer cells and neighboring cells (fibroblasts, endothelial cells, adipocytes, innate and adaptive immune cells) in the tumor microenvironment that coordinate to regulate metastasis. We also highlight the role of exosomes and circulating tumor cells in facilitating breast cancer metastasis. We discuss some key markers associated with stromal cells in the breast tumor environment and their potential to predict patient survival and guide treatment. Finally, we will provide some brief perspectives on how current technologies may lead to the development of more effective therapies for the clinical management of breast cancer patients.

Twelfth Annual ENBDC Workshop: Methods in Mammary Gland Biology and Breast Cancer.

The twelfth annual workshop of the European Network for Breast Development and Cancer focused on methods in mammary gland biology and breast cancer, was scheduled to take place on March 26-28, 2020, in Weggis, Switzerland. Due to the COVID-19 pandemic, the meeting was rescheduled twice and eventually happened as a virtual meeting on April 22 and 23, 2021. The main topics of the meeting were branching and development of the mammary gland, tumor microenvironment, circulating tumor cells, tumor dormancy and breast cancer metastasis. Novel and unpublished findings related to these topics were presented, with a particular focus on the methods used to obtain them. Virtual poster sessions were a success, with many constructive and fruitful interactions between researchers and covered many areas of mammary gland biology and breast cancer.

Graphene-Based Strategies in Liquid Biopsy and in Viral Diseases Diagnosis.

Graphene-based materials are intriguing nanomaterials with applications ranging from nanotechnology-related devices to drug delivery systems and biosensing. Multifunctional graphene platforms were proposed for the detection of several typical biomarkers (i.e., circulating tumor cells, exosomes, circulating nucleic acids, etc.) in liquid biopsy, and numerous methods, including optical, electrochemical, surface-enhanced Raman scattering (SERS), etc., have been developed for their detection. Due to the massive advancements in biology, material chemistry, and analytical technology, it is necessary to review the progress in this field from both medical and chemical sides. Liquid biopsy is considered a revolutionary technique that is opening unexpected perspectives in the early diagnosis and, in therapy monitoring, severe diseases, including cancer, metabolic syndrome, autoimmune, and neurodegenerative disorders. Although nanotechnology based on graphene has been poorly applied for the rapid diagnosis of viral diseases, the extraordinary properties of graphene (i.e., high electronic conductivity, large specific area, and surface functionalization) can be also exploited for the diagnosis of emerging viral diseases, such as the coronavirus disease 2019 (COVID-19). This review aimed to provide a comprehensive and in-depth summarization of the contribution of graphene-based nanomaterials in liquid biopsy, discussing the remaining challenges and the future trend; moreover, the paper gave the first look at the potentiality of graphene in COVID-19 diagnosis.