DNA‐Based Single Molecule Force Sensor For Characterization of α₅β₁ Integrin Tension Required for Invadopodia Formation and Maturation in Cancer Cells

Abstract

Invadopodia are involved in cancer invasion by generating mechanical forces and secreting proteolytic enzymes. It is hypothesized that physical forces applied to integrin, especially α 5 β 1 integrin, are strongly associated with the generation of invadopodial forces and protrusive activity of invadopodia; however, their mechanical relationship remains elusive. Here, a new deoxyribonucleic acid-based force probe is developed for mapping α 5 β 1 integrin tension with single-molecule precision. Using this probe, the formation and maturation of invadopodia depending on integrin type and tension are investigated. In addition, the spatio-temporal analysis of the integrin tension map is performed to measure changes in integrin tension and invadopodial force in each stage of invadopodia development. Consequently, it is found that α 5 β 1 integrin tension above 40 pN is critical not only for adhesion but also for the maturation of invadopodia, eventually leading to the generation of a strong invadopodial force greater than 100 pN through α 5 β 1 integrinligand complexes with actomyosin contractility. This biophysical mechanism underlying the invadopodia formation and mechanical activation may provide new insights into cancer invasion and metastasis.

Characterization of Integrin Molecular Tension of Human Breast Cancer Cells on Anisotropic Nanopatterns

“…In addition to the TGT ruptures, in all tested conditions, punctate fluorescent signal loss under cells (named “ventral rupture”) was observed. This might be caused by DNase recruited in invadopodia or invadopodia activity in the MDA-MB-231 cells ( Pal et al, 2021 ; Kim et al, 2022 ). For the MCF7 cells, the ventral rupture was rarely found; instead, the edge rupture was dominant in all conditions ( Figure 2B ).…”

Recent advances in label-free imaging of cell–matrix adhesions

“…Recently, Kim et al developed a novel TGT probe based on an ATN-16 ligand for specific binding to a 5 b 1 integrin. 99 As seen in Fig. 5a, a force tolerance of 43 pN or 54 pN can be controlled by the location of biotins on the bottom DNA strand, while T tol of 4100 pN was estimated by disassociation of the biotin-streptavidin bond.…”

Biophysical interplay between extracellular matrix remodeling and hypoxia signaling in regulating cancer metastasis

“…To modulate the specific force delivered by the integrins, a tension gauge tether (TGT) was prepared using an oligonucleotide ( Wang and Ha, 2013 ). The TGT method has shown that the adhesion and invadopodia maturation of metastatic cancer cells necessitate the presence of a particular integrin type, namely, α5β1 integrin, along with integrin tension exceeding 40pN ( Kim et al, 2022 ). Furthermore, a micro-confinement TGT (µC-TGT) has been developed to comprehend alterations in integrin-mediated force during cell migration and adhesion within restricted microchannels.…”