Quantification Of Cancer Cells Research Articles

Logic Signal Amplification System for Sensitive Electrochemiluminescence Detection and Subtype Identification of Cancer Cells.

Achieving sensitive detection and accurate identification of cancer cells is vital for diagnosing and treating the disease. Here, we developed a logic signal amplification system using DNA tetrahedron-mediated three-dimensional (3D) DNA nanonetworks for sensitive electrochemiluminescence (ECL) detection and subtype identification of cancer cells. Specially designed hairpins were integrated into DNA tetrahedral nanostructures (DTNs) to perform a catalytic hairpin assembly (CHA) reaction in the presence of target microRNA, forming hyperbranched 3D nanonetworks. Benefiting from the "spatial confinement effect," the DNA tetrahedron-mediated catalytic hairpin assembly (DTCHA) reaction displayed significantly faster kinetics and greater cycle conversion efficiency than traditional CHA. The resulting 3D nanonetworks could load a large amount of Ru(phen)32+, significantly enhancing its ECL signal, and exhibit detection limits for both miR-21 and miR-141 at the femtomolar level. The biosensor based on modular logic gates facilitated the distinction and quantification of cancer cells and normal cells based on miR-21 levels, combined with miR-141 levels, to further identify different subtypes of breast cancer cells. Overall, this study provides potential applications in miRNA-related clinical diagnostics.

A Novel Approach for Quantifying Cancer Cells Showing Hybrid Epithelial/Mesenchymal States in Large Series of Tissue Samples: Towards a New Prognostic Marker.

In cancer biology, epithelial-to-mesenchymal transition (EMT) is associated with tumorigenesis, stemness, invasion, metastasis, and resistance to therapy. Evidence of co-expression of epithelial and mesenchymal markers suggests that EMT should be a stepwise process with distinct intermediate states rather than a binary switch. In the present study, we propose a morphological approach that enables the detection and quantification of cancer cells with hybrid E/M states, i.e., which combine partially epithelial (E) and partially mesenchymal (M) states. This approach is based on a sequential immunohistochemistry technique performed on the same tissue section, the digitization of whole slides, and image processing. The aim is to extract quantitative indicators able to quantify the presence of hybrid E/M states in large series of human cancer samples and to analyze their relationship with cancer aggressiveness. As a proof of concept, we applied our methodology to a series of about a hundred urothelial carcinomas and demonstrated that the presence of cancer cells with hybrid E/M phenotypes at the time of diagnosis is strongly associated with a poor prognostic value, independently of standard clinicopathological features. Although validation on a larger case series and other cancer types is required, our data support the hybrid E/M score as a promising prognostic biomarker for carcinoma patients.

Whole-Cell Impedance Analysis for Highly and Poorly Metastatic Cancer Cells

A micro electrical impedance spectroscopy (muEIS) system has been developed and implemented to analyze highly and poorly metastatic head and neck cancer (HNC) cell lines with single-cell resolution. The microsystem has arrays of 16 impedance analysis sites, each of which is capable of capturing a single cell and analyzing its whole-cell electrical impedance spectrum. This muEIS system was used to obtain the electrical impedance spectra of the poorly metastatic HNC cell line 686 LN and the highly metastatic HNC cell line 686 LN-M4e over a frequency range of 40 Hz - 10 MHz. The 686 LN cells had higher impedance phase compared to that of 686 LN-M4e cells at frequencies between 50 kHz and 2 MHz. This result demonstrates that the metastatic state of HNC cells can be distinguished using the developed muEIS system. This system is expected to serve as a powerful tool for future detection and quantification of cancer cells from various tumor stages.

Experimental Metastasis Assays in the Chick Embryo

Experimental metastasis assays are used to measure the ability of cancer cells to grow in secondary organs following injection of the cells into the circulation of an experimental animal. The chicken embryo provides an alternative to the more commonly used assays in mice. Details of the experimental metastasis assay in chick embryo are provided, including protocols for maintenance of fertilized chicken eggs, injection of cells into the circulation of 11-day-old chick embryos, recovery and quantification of cancer cells from chick liver using the ouabain plating assay, labeling of cells with fluorescent nanospheres, and monitoring of individual steps in the metastatic process in the chick chorioallantoic membrane using intravital videomicroscopy. These assays provide a cost-effective, readily accessible, and rapid approach for studying the process of cancer metastasis.