Biology subjects

Luty, M.

Publications and source records attributed to Luty, M..

3 recordsLinked to original sources

bioRxiv2025

Offsetting ROS-mediated arrest of endothelial fenestration dynamics permits long-term optical super-resolution- and AFM-imaging

Advances in cell biology demand methods that resolve the structure and dynamics of subcellular organelles in living cells. Live-cell super-resolution fluorescence microscopy meets this need but is constrained by phototoxicity, which disturbs cellular function and biases interpretation. Liver sinusoidal endothelial cells (LSECs), with their physiologically critical and highly dynamic fenestrations, represent a particularly challenging model system. We show that photoactivation-generated reactive oxygen species (ROS) are the primary cause of fenestration arrest during fluorescence imaging. Using three-dimensional structured illumination microscopy (3D SR-SIM), we systematically evaluated fluorophores and ROS scavengers to optimize imaging conditions. A combination of BioTracker staining and CO2-independent medium supplemented with N-acetylcysteine (NAC) preserved fenestration dynamics without altering fenestration number or size. Complementary atomic force microscopy (AFM) confirmed ROS-dependent impairment of fenestration dynamics and revealed nanomechanical changes upon illumination. These findings establish the mechanism underlying imaging-induced artefacts in LSECs and provide a broadly applicable strategy to extend live-cell super-resolution microscopy.

cell biology↗

bioRxiv2024

Tubulin-Targeted Therapy in Melanoma Increases Cell Invasive Potential by Activation of Actomyosin Cytoskeleton - an in vitro study

One of the most dangerous aspects of cancers is their ability to metastasize, which is the leading cause of death. Hence, it holds significance to develop therapies targeting the eradication of cancer cells, in parallel, inhibiting metastases in cells surviving the applied therapy. Here, we focused on two melanoma cell lines - WM35 and WM266-4 - representing the less and more invasive melanomas. We investigated mechanisms of cellular processes regulating the activation of actomyosin being the effect of colchicine treatment. Additionally, we investigated biophysical aspects of supplement therapy using Rho-associated protein kinase (ROCK) inhibitor (Y-27632), and myosin II inhibitor ((-)-blebbistatin), focusing on the microtubules and actin filaments. We analyzed their effect on the proliferation, migration, and invasiveness of melanoma cells, supported by studies on cytoskeletal architecture using confocal fluorescence microscopy and nanomechanics using atomic force microscopy and novel method based on constriction channels. Our results showed that colchicine inhibits the migration of most melanoma cells, while for a small cell population, it paradoxically increases their migration and invasiveness. These changes are also accompanied by the formation of stress fibers compensating for the loss of microtubules. Simultaneous administration of selected agents led to the inhibition of this compensatory effect. Collectively, our results highlighted that colchicine led to actomyosin activation and increased cancer cell invasiveness. We emphasized a cellular pathway of Rho-ROCK-dependent actomyosin contraction to be responsible for the increased invasive potential of melanoma cells in tubulin-targeted therapy. HighlightsO_LIColchicine strongly increased (trans)migration in the subpopulation of melanoma cells. C_LIO_LIColchicine disrupted tubulin but compensated for the activation of the actomyosin network. C_LIO_LIRho-ROCK-targeted or myosin-targeted therapies vanished the side-effect of colchicine. C_LIO_LIIncreased actin polymerisation correlated with the transit time in the constriction channel. C_LIO_LIElastic modulus variations reflected observed alterations in the actomyosin network. C_LI

biophysics↗

bioRxiv2024

Migration, proliferation, and elasticity of bladder cancer cells on lectin-coated surfaces

The alterations in migration, proliferation, and mechanics of cells observed during cancer progression can potentially be linked to enhanced tumor invasiveness. These properties are frequently attributed to the ability to form distant metastasis; however, the direct mutual connection between these properties is not always proven. Here, we studied the migratory, proliferative, and mechanical phenotype of three bladder cancer cells originating from various stages of cancer progression, i.e., non-malignant cell cancer of ureter (HCV29 cells), bladder carcinoma (HT1376 cells) and transitional bladder carcinoma (T24 cells). The results were linked with the organization of actin filaments because of their major role in cell migration. The results classified cells into non-malignant, non-invasive, and invasive, revealing the significant impact of actin filaments in bladder cancer invasion. Based on the reported changes in cancer cell glycosylation, the potential applicability of the observed cancer-related changes to identify invasive cells was demonstrated for the lectin-coated surfaces, which is the potential surface modification for biosensors.

biophysics↗