Biology subjects

Pogoda, K.

Publications and source records attributed to Pogoda, K..

9 recordsLinked to original sources

bioRxiv2026

An Effective Metal Nanoparticle-Based Drug Delivery System for an In Vitro Model of Non Small Cell Lung Cancer

This study presents the development and spectroscopic characterization of an erlotinib-functionalized gold nanoparticle (erlotinib:AuNP) nanosystem designed for targeted delivery to metastatic non-small cell lung cancer H1299 cells. Initial MTS assays demonstrated that free erlotinib induced a concentration-dependent reduction in cell viability, while 0.1 {micro}M erlotinib exhibited negligible cytotoxicity and was therefore selected for nanosystem fabrication. AuNPs alone showed minimal toxicity toward H1299 cells over the investigated concentration range. Following conjugation of erlotinib with AuNPs, the resulting nanosystems reduced cell viability to approximately 60%, indicating enhanced biological activity of the drug after nanoparticle-assisted delivery. Fluorescence microscopy confirmed the intracellular internalization of the nanosystems in H1299 cells, with nanoparticle aggregates predominantly localized in the perinuclear and perimitochondrial regions. Three-dimensional Raman spectroscopy (3D RS) mapping further verified the intracellular localization of the conjugates through characteristic Raman signatures of erlotinib:AuNPs. Importantly, 3D RS enabled detection of nanosystems at concentrations below the sensitivity limit of fluorescence imaging, demonstrating superior analytical performance for intracellular nanosystem tracking. Atomic force microscopy-infrared (AFM-IR) spectroscopy coupled with principal component analysis (PCA) demonstrated substantial biochemical modifications induced by the erlotinib:AuNP nanosystems, including enhanced lipid-related spectral features and significant alterations in protein secondary structure, particularly the increased contribution of unordered and antiparallel {beta}-turn conformations. The obtained results demonstrate that combining plasmonic nanocarriers with advanced vibrational spectroscopy enables highly sensitive monitoring of intracellular drug delivery and nanosystem-induced biochemical responses in cancer cells.

biophysics↗

bioRxiv2026

Lipid droplet isolation as a novel platform for spectroscopic investigation of cargo modifications

Lipid droplets (LDs) are dynamic organelles involved in metabolic regulation and cellular stress responses, yet their biochemical heterogeneity and treatment-dependent remodeling in the context of radiotherapy remain poorly understood. Here, we present the first label-free Raman spectroscopic analysis of isolated lipid droplets (iLDs) from normal Schwann cells and malignant peripheral nerve sheath tumor (MPNST) cells subjected to cannabidiol (CBD) treatment, ionizing radiation, and their combination. Raman spectroscopy revealed pronounced chemical heterogeneity of iLDs both between and within cell types, reflecting differences in acyl chain organization, conformational order, and lipid class composition. CBD treatment induced substantial lipid remodeling in Schwann cells, giving rise to multiple iLD subpopulations, whereas MPNST cells exhibited a more constrained response. Irradiation altered lipid droplet heterogeneity in a cell-type-dependent manner, while combined CBD treatment and irradiation induced characteristic alterations in LD cargo that differed markedly between Schwann and MPNST cells, highlighting lipid droplets as sensitive reporters of metabolic reprogramming and stress adaptation. Overall, these findings establish Raman-based lipid droplet profiling as a powerful approach for resolving treatment-specific metabolic remodeling at the suborganelle level and provide new insight into lipid-mediated mechanisms underlying radiosensitization in cancer cells.

biophysics↗

bioRxiv2026

Spectrolipidomics of glial cell lines: a deuterated probe for semiquantitative monitoring of cannabidiol-induced cholesterol modulation

Understanding lipid metabolism in peripheral glial cells is crucial for elucidating the molecular mechanisms underlying neurodegeneration, cancerogenesis and therapy resistance. Here, we introduce a spectrolipidomic sensing approach that integrates Raman, FT-IR, and AFM-IR spectroscopy to monitor nanoscale cholesterol remodeling in glial cells exposed to cannabidiol (CBD). Deuterated cholesterol (dChol) was employed as an intrinsic, spectroscopically active molecular probe, enabling selective tracking of cholesterol transformations through characteristic C-D vibrational signatures within the 2300-2000 cm-1 silent spectral region. Multimodal vibrational spectroscopy provided label-free, spatially resolved insight into lipid organization, redistribution, and metabolic reprogramming across micro- and nanoscales. The dChol probe enabled semi-quantitative evaluation of cholesterol uptake, esterification, and membrane integration, revealing that the sequence of CBD exposure, before or after probe addition, triggers distinct lipid metabolic pathways. Raman spectroscopy demonstrated superior sensitivity, with reliable detection of intracellular dChol at concentrations as low as 10 {micro}M, outperforming FT-IR imaging and confirming its suitability for cell lipid sensing. This analytical platform establishes deuterium-labeled lipids as powerful vibrational sensors for probing lipid metabolism and CBD-induced remodeling in situ. The presented spectrolipidomic framework paves the way for next-generation, spectroscopy-based biosensing systems capable of visualizing lipid dynamics, membrane restructuring, and drug- lipid interactions under pharmacological or environmental stress conditions. HighlightsO_LIDeuterated cholesterol (dChol) used as an intrinsic vibrational sensor C_LIO_LILower detection threshold of intracellular dChol for Raman than FT-IR C_LIO_LIAFM-IR reveals phases of lipid droplet formation in nanoscale C_LIO_LICBD alters cholesterol uptake, esterification, and lipid unsaturation profiles C_LI

biophysics↗

bioRxiv2023

High resolution optical spectroscopy for the evaluation of cannabidiol efficiency as a radiation therapy support of peripheral nervous system tumors

An increasing number of scientific papers discuss the promising therapeutic potential of cannabidiol (CBD) not only for the treatment of cancer, but also for asthma and neurodegenerative disorders. This happens mainly due to its proven anticancer, anti-inflammatory, and antioxidant properties. In the field of cancer research, the use of CBD has already been investigated on malignant tumors of the central nervous system, like gliomas. So far, CBD has not yet been explored in the therapy of peripheral nervous system (PNS) tumors. Peripheral nerves reside outside the central nervous system, therefore peripheral nerve tumors can occur anywhere in the body. When the tumor develops within large blood vessels, spinal nerves or involves more than one peripheral nerve, radiotherapy is recommended. Due to high doses of ionizing radiation, complications such as dizziness, damage to adjacent nerves, or malignancy of the lesion may occur. Therefore, it is important to develop a treatment scheme that efficiently reduces tumor volume while maintaining the normal functions of the surrounding cells and decrease the side effects. Herein, we proposed to combine hyperspectral imaging using Raman and FTIR spectroscopy and AFM-IR technique as a novel approach to monitor the therapeutic efficacy of CBD. Performed studies reviled the dual effect of CBD, that protects normal cells from ionizing radiation and increases its toxicity in cancer cells.

biophysics↗

bioRxiv2020

The Atr-Chek1 pathway inhibits axon regeneration in response to Piezo-dependent mechanosensation

Atr is a serine/threonine kinase, known to sense single-stranded DNA breaks and activate the DNA damage checkpoint by phosphorylating Chek1, which inhibits Cdc25, causing cell cycle arrest. This pathway has not been implicated in neuroregeneration. We show that in Drosophila sensory neurons, removing Atr or Chek1, or overexpressing Cdc25 promotes regeneration, whereas Atr or Chek1 overexpression, or Cdc25 knockdown impedes regeneration. Inhibiting the Atr-associated checkpoint complex in neurons promotes regeneration and improves synapse/behavioral recovery after CNS injury. Independent of DNA damage, Atr responds to the mechanical stimulus elicited during regeneration, via the mechanosensitive ion channel Piezo and its downstream NO signaling. Sensory neuron-specific knockout of Atr in adult mice, or pharmacological inhibition of Atr-Chek1 in mammalian neurons in vitro and in flies in vivo enhance regeneration. Our findings reveal the Piezo-Atr-Chek1-Cdc25 axis as an evolutionarily conserved inhibitory mechanism for regeneration, and identify potential therapeutic targets for treating nervous system trauma.

neuroscience↗

bioRxiv2020

Tumor stiffening reversion through collagen crosslinking inhibition improves T cell migration and anti-PD-1 treatment

Only a fraction of cancer patients benefits from immune checkpoint inhibitors. This may be partly due to the dense extracellular matrix (ECM) that forms a barrier for T cells. Comparing 5 preclinical mouse tumor models with heterogeneous tumor microenvironments, we aimed to relate the rate of tumor stiffening with the remodeling of ECM architecture and to determine how these features affect intratumoral T cell migration. An ECM-targeted strategy, based on the inhibition of lysyl oxidase (LOX) was used. In vivo stiffness measurements were found to be strongly correlated with tumor growth and ECM crosslinking but negatively correlated with T cell migration. Interfering with collagen stabilization reduces ECM content and tumor stiffness leading to improved T cell migration and increased efficacy of anti-PD-1 blockade. This study highlights the rationale of mechanical characterizations in solid tumors to understand resistance to immunotherapy and of combining treatment strategies targeting the ECM with anti-PD-1 therapy.

cancer biology↗

bioRxiv2019

Role of a kinesin motor in cancer cell mechanics

Molecular motors play important roles in force generation, migration and intracellular trafficking. Changes in specific motor activities are altered in numerous diseases. KIF20A, a motor protein of the kinesin-6 family, is overexpressed in bladder cancer, and KIF20A levels correlate negatively with the clinical outcome. We report here a new role for the KIF20A kinesin motor protein in intracellular mechanics. Using optical tweezers to probe intracellular mechanics and surface AFM to probe cortical mechanics, we first confirm that bladder cells soften with increasing cancer grade. We then show that inhibiting KIF20A makes the intracellular environment softer for both high and low grade bladder cancer cells. Upon inhibition of KIF20A cortical stiffness also decreases in lower grade cells, while it surprisingly increases in higher grade malignant cells. Changes in cortical stiffness correlate with the interaction of KIF20A with myosin IIA. Moreover, KIF20A negatively regulates bladder cancer cell motility irrespective of the underlying substrate stiffness. Our results reveal a central role for a microtubule motor in cell mechanics and migration in the context of bladder cancer.

biophysics↗

bioRxiv2019

Vimentin protects the structural integrity of the nucleus and suppresses nuclear damage caused by large deformations

Mammalian cells frequently migrate through tight spaces during normal embryogenesis, wound healing, diapedesis or in pathological situations such as metastasis. The nucleus has recently emerged as an important factor in regulating 3D cell migration. At the onset of migratory behavior, cells often initiate the expression of vimentin, an intermediate filament protein which forms networks extending from a juxtanuclear cage to the cell periphery. However, the role of vimentin intermediate filaments (VIFs) in regulating nuclear shape and mechanics remains unknown. Here, we used wild type and vimentin-null mouse embryonic fibroblasts to show that VIFs regulate nuclear shape, motility, and the ability of cells to resist large deformations. The results show that loss of VIFs alters nuclear shape, reduces perinuclear stiffness, and enhances motility in 3D. These changes increase nuclear rupture and activation of DNA damage repair mechanisms, which are rescued by exogenous re-expression of vimentin. Our findings show that VIFs provide mechanical support to protect the nucleus and genome during migration.

cell biology↗

bioRxiv2018

Loss of vimentin intermediate filaments decreases peri-nuclear stiffness and enhances cell motility through confined spaces

The migration of cells through tight constricting spaces or along fibrous tracks in tissues is important for biological processes, such as embryogenesis, wound healing, and cancer metastasis, and depends on the mechanical properties of the cytoskeleton. Migratory cells often express and upregulate the intermediate filament protein vimentin. The viscoelasticity of vimentin networks in shear deformation has been documented, but its role in motility is largely unexplored. Here, we studied the effects of vimentin on cell motility and stiffness using mouse embryo fibroblasts derived from wild-type and vimentin-null mice. We find that loss of vimentin increases motility through small pores and along thin capillaries. Atomic force microscopy measurements reveal that the presence of vimentin enhances the perinuclear stiffness of the cell, to an extent that depends on surface ligand presentation and therefore signaling from extracellular matrix receptors. Together, our results indicate that vimentin hinders three-dimensional motility by providing mechanical resistance against large strains and may thereby protect the structural integrity of cells.

biophysics↗