Biology subjects

Gligorijevic, B.

Publications and source records attributed to Gligorijevic, B..

10 recordsLinked to original sources

bioRxiv2026

Pancreatic cancer fibrosis activates protumorigenic Schwann cells through a nuclear mechanosensing mechanism.

BackgroundFibrosis and tumor innervation are two features of the tumor microenvironment (TME) that contribute directly to the lethality of pancreatic ductal adenocarcinoma (PDAC), but their potential interactions have not been explored. Moreover, although it is known that activated Schwann cells (SCs) stimulate cancer cell invasion, it remains unclear how SCs are activated. ObjectiveWe determined how SCs are activated in the pancreatic fibrotic microenvironment. DesignThe correlation between physical features of the microenvironment and SC activation was assessed in human patient samples and in mice by SC c-Jun phosphorylation monitoring, atomic force microscopy and multiphoton live imaging. Several in vitro models in which forces were applied to SCs expressing a reporter for c-Jun phosphorylation and RNA-Seq analysis were used to decipher the cellular and molecular mechanisms of SC activation. ResultsNerves surrounded by stiff stroma present higher SC activation. Intravital imaging shows a matrix dependent SC activation. Mechanical forces on SCs induce c-Jun phosphorylation in SCs in a non-canonical manner that involves a nuclear sensing machinery with the proinflammatory enzyme Phospholipase A2. ConclusionFibrosis enhances the protumorigenic impact of innervation by activating SCs via a mechanism in which nuclear compression triggers non-canonical activation of the AP-1 transcription factor complex. Pancreatic fibrosis alone, without cancer cells, is sufficient to activate SCs, suggesting this mechanism may be common across non-malignant pancreatic diseases. Notably, SCs are more sensitive to mechanical activation than PDAC cells. These findings reveal TME interactions that may guide future microenvironment-targeted PDAC therapies. What is already known on this topicThe pancreatic cancer tumor microenvironment is highly innervated and fibrotic, two components of the tumor microenvironment that regulate tumorigenesis. How they impact each other is unknown. Schwann cells have emerged as a significant protumorigenic player, but the triggers of Schwann cell activation remain undefined. What this study addsWe establish that fibrosis induces Schwann cell activation and characterize the mechanism by which it occurs. We uncovered a mechanical mode of action that deforms nuclear membrane and activates c-Jun in Schwann cells, which contradicts the traditional view of c-Jun activation through a stimulus detected at the plasma membrane. How this study might affect research, practice or policyThis study provides a better understanding of the biology of pancreatic ductal adenocarcinoma and supports the development of novel precision therapies that target the fibrotic microenvironment to impact the protumorigenic effect of tumor innervation.

cancer biology↗

bioRxiv2026

Sensory neurons inhibit invadopodia and metastasis via direct CGRP-RAMP1-cAMP signaling to cancer cells

Breast cancer is globally the most common cancer among women. Although the five-year survival rate exceeds 80% for patients with localized disease, it drops to approximately 30% once metastasis occurs, underscoring the urgent need to define mechanisms that drive metastatic progression. Breast is a highly innervated organ and most of its innervation is sensory. However, whether sensory neurons can directly impact breast cancer cells remains an understudied topic. Here, we show that mammary tumors have increased CGRP sensory innervation. Using our novel microfluidic Device for Cancer cell-Axon Interaction Testing (DACIT), we demonstrate that the presence of axons strongly inhibits ECM-degrading ability of cancer cells. The sensory neuron secretome suppresses assembly and function of invadopodia, which are cancer cell protrusions controlling ECM degradation, and essential for intravasation and metastasis. We identify calcitonin gene-related peptide (CGRP) as the key component of the sensory neuron secretome responsible for the inhibitory effect. CGRP signaling occurs through the CRLR/RAMP1 receptor complex expressed by breast cancer cells, inducing a rapid increase in intracellular cAMP levels in breast cancer cells, followed by an increase in RhoC activity and suppression of invadopodia and ECM degradation. Loss of RAMP1 function enhances 3D spheroid invasion, cancer cell motility in vivo and significantly increases the number and the size of lung metastatic foci. Consistently, in silico analyses of both mouse and human RNASeq data point to a link between increasingly invasive subtypes with a gradual decrease in expression of RAMP1 and CRLR. To validate in silico findings, we compare RAMP1 expression in the patient breast tumors with adjacent normal tissues, confirming the invasive breast tumors have reduced levels of RAMP1. Together, our findings identify a protective role for the paracrine CGRP signaling in limiting breast cancer invasion and metastasis. We also demonstrate how cancer cells circumvent CGRP inhibition by suppressing RAMP1 expression, highlighting CGRP-RAMP1-cAMP axis as a potential therapeutic target in breast cancer.

cancer biology↗

bioRxiv2025

Cell cycle- and EMT-dependent expression of Filip1L controls invadopodia in breast cancer cells

Invadopodia are actin- and protease-rich membrane structures that enable cancer cells to degrade extracellular matrix (ECM). Invadopodia activity is cell cycle-dependent, but how their regulation across the cell cycle is influenced by epithelial-to-mesenchymal transition (EMT) remains unclear. We show that as the EMT progresses, cell engagement in invadopodia-mediated ECM degradation shits from G2 phase in Early E/M cells to G1 phase in Late E/M or M cells. Using bulk mRNA sequencing of Early- versus Late- E/M cells sorted by cell cycle phase, we identified FILIP1L as an EMT- and cell cycle-regulated candidate whose expression peaks in the invasive phase of each cell state: G2 in Early E/M cells and G1 in Late E/M cells. We next demonstrated that FILIP1L is a novel invadopodia component, whose loss increases ECM degradation while impairing migration and 3D invasion. In mouse models, FILIP1L KD tumors develop fewer metastatic colonies, suggesting that FILIP1L supports productive invasion by coordinating between invadopodia and migratory cell states. FILIP1L expression increases with EMT progression and correlates with poor outcomes in breast cancer patients. Together, these findings identify a previously unrecognized link between EMT, cell cycle and invadopodia and establish FILIP1L as the key regulator of this process.

cancer biology↗

bioRxiv2024

Retrograde tracing of breast cancer-associated sensory neurons

Breast cancer is one of the leading causes of mortality among women. The tumor microenvironment, consisting of host cells and extracellular matrix, has been increasingly studied for its interplay with cancer cells, and the resulting effect on tumor progression. While the breast is one of the most innervated organs in the body, the role of neurons, and specifically sensory neurons, has been understudied, mostly for technical reasons. One of the reasons is the anatomy of sensory neurons: sensory neuron somas are located in the spine, and their axons can extend longer than a meter across the body to provide innervation in the breast. Next, neurons are challenging to culture, and there are no cell lines adequately representing the diversity of sensory neurons. Finally, sensory neurons are responsible for transporting several different types of signals to the brain, and there are many different subtypes of sensory neurons. The subtypes of sensory neurons which innervate and interact with breast tumors are unknown. To establish the tools for labeling and subtyping neurons that interact with breast cancer cells, we utilized two retrograde tracers standards in neuroscience, wheat-germ agglutinin (WGA) and cholera toxin subunit B (CTB). In vitro, we employed primary sensory neurons isolated from mouse dorsal root ganglia, cultured in a custom-built microfluidic device DACIT, that mimics the anatomical compartmentalization of the sensory neurons soma and axons. In vivo, we utilized both syngeneic and transgenic mouse models of mammary carcinoma. We show that CTB and WGA trace different but overlapping sensory neuronal subpopulations: while WGA is more efficient in labeling CGRP+ neurons, CTB is superior in labeling the NF200+ neurons. Surprisingly, both tracers are also taken up by a significant population of breast cancer cells, both in vitro and in vivo. In summary, we have established methodologies for retrograde tracing of sensory neurons interacting with breast cancer cells. Our tools will be useful for future studies of breast tumor innervation, and development of therapies targeting breast cancer-associated neuron subpopulations of sensory neurons.

cancer biology↗

bioRxiv2024

DACIT: Device for Axon - Cancer cell Interaction Testing in 2D and 3D

There is increasing interest in studying the role of peripheral innervation in tumor growth and metastasis. However, in vitro studies of interactions between cancer cells and axonal projections are technically challenging. To address this, we have developed a microfluidic Device for Axon-Cancer cell Interaction Testing in 2D and 3D (DACIT). We show that DACIT successfully separates neuronal soma from the axons and cancer cells into two compartments, which can be exposed to similar, or different growth conditions, depending on the experimental needs. We compare neoaxonogenesis using either the PC-12 cell line or primary embryonic or adult sensory neurons, demonstrating superior neurite growth in primary cells. Additionally, we show that DACIT can accommodate assessing growth and 3D invasion of tumor spheroids, due to its unique height profile. Hence, DACIT can be used to analyze cancer cell interactions with axons in most typical cell biology assays such as proliferation, invasion, and calcium activity which we demonstrate on examples of imaging transients in GCaMP6-labeled neurons, invadopodia assay, and 3D cancer spheroid invasion.

cancer biology↗

bioRxiv2023

Trogocytosis of cancer-associated fibroblasts promotes pancreatic cancer growth and immune suppression via phospholipid scramblase anoctamin 6 (ANO6).

In pancreatic ductal adenocarcinoma (PDAC), the fibroblastic stroma constitutes most of the tumor mass and is remarkably devoid of functional blood vessels. This raises an unresolved question of how PDAC cells obtain essential metabolites and water-insoluble lipids. We have found a critical role for cancer-associated fibroblasts (CAFs) in obtaining and transferring lipids from blood-borne particles to PDAC cells via trogocytosis of CAF plasma membranes. We have also determined that CAF-expressed phospholipid scramblase anoctamin 6 (ANO6) is an essential CAF trogocytosis regulator required to promote PDAC cell survival. During trogocytosis, cancer cells and CAFs form synapse-like plasma membranes contacts that induce cytosolic calcium influx in CAFs via Orai channels. This influx activates ANO6 and results in phosphatidylserine exposure on CAF plasma membrane initiating trogocytosis and transfer of membrane lipids, including cholesterol, to PDAC cells. Importantly, ANO6-dependent trogocytosis also supports the immunosuppressive function of pancreatic CAFs towards cytotoxic T cells by promoting transfer of excessive amounts of cholesterol. Further, blockade of ANO6 antagonizes tumor growth via disruption of delivery of exogenous cholesterol to cancer cells and reverses immune suppression suggesting a potential new strategy for PDAC therapy.

cancer biology↗

bioRxiv2021

Invadopodia enable cooperative invasion and metastasis of breast cancer cells

Invasive and non-invasive cancer cells can invade together during the cooperative invasion. However, the events leading to it, role of EMT and the consequences this may have on metastasis are unknown. In this study, we demonstrate that the isogenic 4T1 and 67NR breast cancer cells sort from each other in 3D spheroids, followed by cooperative invasion. By time-lapse microscopy, we show that the invasive 4T1 cells move more persistently compared to non-invasive 67NR, sorting and accumulating at the spheroid-ECM interface, a process dependent on cell-ECM adhesions and independent from E-cadherin cell-cell adhesions. Elimination of invadopodia in 4T1 cells blocks invasion, demonstrating that invadopodia requirement is limited to leader cells. Importantly, we demonstrate that cells with and without invadopodia can also engage in cooperative metastasis in preclinical mouse models. Altogether, our results suggest that a small number of cells with invadopodia can drive the metastasis of heterogeneous cell clusters.

cancer biology↗

bioRxiv2018

Invadopodia degrade ECM in the G1 phase of the cell cycle

Invadopodia are cancer cell protrusions rich in structural proteins (e.g. Tks5, cortactin) and proteases (e.g. MT1-MMP) and are responsible for degradation of the extracellular matrix (ECM). Tumor cell invasion and metastasis require cancer cells to be both proliferative and invasive, i.e. migrate through the tissue and assemble invadopodia. While several studies addressed how cell motility parameters change throughout the cell cycle, the relationship between invadopodia and cell cycle progression has not been elucidated. In this study, using invadopodia- and cell cycle- fluorescent markers, we show in 2D and 3D cell cultures, as well as in vivo, that breast carcinoma cells assemble invadopodia and invade into the surrounding ECM preferentially during the G1 phase of the cell cycle. Cells synchronized in the G0/G1 phase of the cell cycle degrade at significantly higher levels during the first 20 hours post-synchronization release. Consistent with this, mRNA and protein levels of the invadopodia key components, cortactin and MT1-MMP, peak at 14 hours post-release. Cell cycle progression is faster in cells in which invadopodia are abolished (by Tks5 knockdown), evidenced by earlier induction of cyclins A and B. A close look at the regulators of G1 revealed that the overexpression of p27kip1, but not p21cip1, causes faster turnover of invadopodia and increased ECM degradation. Furthermore, both endogenous and over-expressed p27kip1 localizes to the sites of invadopodia assembly. Taken together, these findings suggest that invadopodia function is tightly linked to cell cycle progression and is controlled by specific cell cycle regulators. Our results caution that this coordination between invasion and cell cycle must be considered when designing effective chemotherapies.

cancer biology↗

bioRxiv2018

Directed, but not random, breast cancer cell migration is faster in the G1 phase of the cell cycle in 2D and 3D environments

Cancer cell migration is essential for the early steps of metastasis, during which cancer cells move through the primary tumor and reach the blood vessels. In vivo, cancer cells are exposed to directional guidance cues, either soluble, such as gradients of growth factors, or insoluble, such as collagen fiber alignment. Depending on the number and strength of such cues, cells will migrate in a random or directed manner. Interestingly, similar cues also stimulate cell proliferation. In this regard, it is not clear whether cell cycle progression affects migration of cancer cells and whether this effect is different in random versus directed migration. In this study, we tested the effect of cell cycle progression on random and directed migration, both in 2D and 3D environments, in the breast carcinoma cell line, FUCCI-MDA-MB-231, using computational image analysis by LEVER. Directed migration in 2D was modeled as chemotaxis along a gradient of soluble EGF inside 10 {micro}m-wide microchannels. In 3D, directed migration was modeled as contact guidance (alignotaxis) along aligned collagen fibers. Time-lapse recordings of cells in 2D and 3D revealed that directed, but not random migration, is cell cycle-dependent. In both 2D and 3D directed migration, cells in the G1 phase of the cell cycle outperformed cells in the G2 phase in terms of migration persistence and instantaneous velocity. These data suggest that in the presence of guidance cues in vivo, breast carcinoma cells in the G1 phase of the cell cycle may be more efficient in reaching vasculature.

cancer biology↗

bioRxiv2017

ECM cross-linking regulates invadopodia dynamics

InvadopodiInvadopodia are membrane protrusions dynamically assembled by invasive cancer cells in contact with extracellular matrix (ECM). Invadopodia are enriched for the structural proteins actin and cortactin, as well as metalloproteases such as MT1-MMP, whose function is to degrade the surrounding ECM. During metastasis, invadopodia are necessary for cancer cell intravasation and extravasation. While signaling pathways involved in the assembly and function of invadopodia are well studied, few studies address invadopodia dynamics and how the cell-ECM interactions contribute to cell invasion. Using iterative analysis based on time-lapse microscopy and mathematical modeling of invasive cancer cells, we found that cells oscillate between invadopodia presence and cell stasis, termed Invadopodia state and invadopodia absence during cell translocation, termed Migration state. Our data suggests that {beta}1-integrin-ECM binding and ECM cross-linking control the duration of each of the two states. By changing the concentration of cross-linkers in 2D and 3D cultures, we generate ECM where 0-0.92 of total lysine residues are cross-linked. Using ECM with a range of cross-linking degrees we demonstrate that the dynamics of invadopodia-related functions have a biphasic relationship to ECM cross-linking. At intermediate levels of ECM cross-linking (0.39), cells exhibit rapid invadopodia protrusion-retraction cycles and rapid calcium spikes, which lead to more frequent MT1-MMP delivery, causing maximal invadopodia-mediated ECM degradation. In contrast, both extremely high or low levels of cross-linking lead to slower invadopodia-related dynamics and lower ECM degradation. Additionally, {beta}1-integrin inhibition modifies dynamics of invadopodia-related functions, as well as the length of time cells spend in either of the states. Collectively, these data suggest that {beta}1-integrin-ECM binding non-linearly translates small physical differences in extracellular environment to differences in the dynamics of cancer cell behaviors. Understanding conditions under which invadopodia can be reduced by subtle environment-targeting treatments may lead to combination therapies for preventing metastatic spread.

cancer biology↗