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Biology subjects

Provenzano, P.

Publications and source records attributed to Provenzano, P..

9 recordsLinked to original sources

Physiomimetic culture bias durotaxis toward soft environments

Directed cell migration underlies many biological phenomena, from embryonic development to tumor metastasis and organ fibrosis. Most cells typically migrate toward stiffer regions of their extracellular matrix -a behavior known as positive durotaxis. Here we show that culture on rigid plastic reinforces this response, whereas preconditioning in soft 3D physiomimetic environments reprograms migration towards softer environments, a phenomenon known as negative durotaxis. Fetal rat lung fibroblasts preconditioned in 3D physiomimetic hydrogels exhibited negative durotaxis and accumulated near [~]5 kPa, corresponding to the physiological stiffness of the lung. In contrast, genetically identical cells maintained on conventional 2D plastic substrates migrated up stiffness gradients, toward stiffer regions. Although both populations displayed a biphasic force-stiffness relationship, they differed in force magnitude and cytoskeletal organization. Molecular-clutch modeling revealed that durotaxis reversal emerges from two distinct mechanical regimes: a mechanosensitive, high-motor-clutch state that stabilizes adhesions on stiff substrates and drives positive durotaxis, and a low-motor, weak-adhesion state in which clutch slippage on the stiff side causes negative durotaxis. Our results show that durotaxis direction is not an intrinsic cellular property. Rather, it emerges from the interplay between motor activity and adhesion dynamics and can be tuned by culture conditions.

biophysics↗

Engineering physically optimized T cells for increased sampling of complex tumor microenvironments

Pancreatic ductal adenocarcinoma (PDA) remains highly lethal, in part, because its dense fibroinflammatory stroma restricts therapy distribution, including adoptive T cell immunotherapies where direct interactions between T and carcinoma cells are essential for effective therapy. While T cell function must be maintained once effector-target engagement occurs, without inducing co-localization subsequent cytotoxic function steps cannot be undertaken. We therefore developed a strategy to "physically optimize" T cells to more effectively sample complex tumor volumes. Informed by pharmacologic perturbations and mathematical modeling we shifted T cell phenotype through expression of constitutively activated RhoA to increase cortical contractility, activation, migration, and sampling in PDA, while showing decreases in exhaustion markers. In CAR T cells this results in more efficient targeting through decreased sampling time and increased engagement with carcinoma cells, consistent with modeling predictions. This significantly increases T cell infiltration and distribution in PDA, resulting in improved tumor control in vivo, suggesting that this is an effective strategy to overcome stromal constraints, improve tumor engagement, and enhance the therapeutic performance of engineered T cell therapies in solid tumors.

bioengineering↗

Collagen-Based Tumor Spheroid Model for Investigating Tumor-Macrophage Interactions through Extracellular Matrix Remodeling

Macrophages in the tumor microenvironment (TME) can constitute up to 50% of tumor mass and play a critical role in cancer cell proliferation, invasion, and metastasis. While their contribution to extracellular matrix (ECM) degradation through matrix metalloproteinases (MMPs) has been explored, the role of other macrophage-derived factors in ECM remodeling and their impacts beyond degradation remain poorly understood. Here, we describe the development of a 3D collagen-based tumor spheroid model to investigate the impact of peripheral blood mononuclear cell (PBMC)-derived macrophages on cancer cell-ECM and cancer cell-macrophage interactions within the TME. We observed that cancer cells stimulated PBMC-derived macrophages into an M2-like phenotype and that tumor spheroid conditioned macrophages (TSCMs) shifted cancer cell populations toward phenotypes with greater invasion distances and reduced circularity, indicative of increased malignancy. Such observations can be explained by macrophage-mediated ECM remodeling. Specifically, we demonstrate that TSCMs secreted a variety of soluble factors that are known to contribute to ECM remodeling, including ECM degradation and fiber realignment. These processes collectively create a tumor-favoring environment by loosening the collagen matrix and aligning fibers that serve as invasion tracks for migrating tumor cells that facilitate cancer cell migration and invasion. This model provides a robust platform to study the interactions between cellular and non-cellular components in the TME and to identify the molecular mechanisms underlying cancer progression. These insights may aid in the development of novel therapeutic strategies targeting macrophage-mediated processes in cancer. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=75 SRC="FIGDIR/small/679587v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@17d1f9forg.highwire.dtl.DTLVardef@1a71500org.highwire.dtl.DTLVardef@53deeeorg.highwire.dtl.DTLVardef@510268_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

A Singular Base Editing Platform for Polyfunctional Multiplex Engineering of Immune Cells

Current methods to engineer antigen-specific receptors rely on randomly integrating vectors or double-strand break induced targeted integration, both of which pose safety risks. To implement an all-in-one tool for multiplex knockout (KO) and knock in (KI), we expand the use of cytosine and adenine base editor (ABE) nickase activity to stimulate homology-directed repair (HDR) and insert clinically relevant chimeric antigen receptors (CARs) into specific loci. Through a novel sgRNA design strategy and a recombinant adeno-associated virus (rAAV) delivered DNA template, we enhanced the efficiency of ABE8e-stimulated HDR in human T cells. By combining KI of CD19-, CD33-, or mesothelin-targeting CARs with >95% quadplex gene KO (B2M/CD3{varepsilon}/PDCD1/CISH), we achieve single-step generation of highly functional off-the-shelf CAR T cell products with enhanced function. Importantly, we found no detectable translocations or significant off-target edits and demonstrated efficacy against multiple cancer lines, and a suppressive 3D spheroid culture model. This efficient engineering process of Iterative Nicking for Synchronous Engineered Reprogramming of T cells (INSERT) establishes a safe, simplified platform for advanced therapeutic CAR T engineering.

bioengineering↗

Abrogating TGFβ signaling in TCR-engineered T cells and enhancing antigen processing by tumor cells promotes sustained therapeutic activity in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDA) is a deadly malignancy with limited effective therapies. Adoptive cell therapy (ACT) is a promising treatment modality for patients with solid tumors but has been limited by the highly fibroinflammatory and immunosuppressive tumor microenvironment (TME). Transforming growth factor-{beta} (TGF{beta}) participates in the inordinately suppressive TME in PDA. Here, we test the impact of selective Tgfbr2 deletion using CRISPR/Cas9 or genetic approaches in mesothelin (Msln)-specific T cell receptor (TCR) engineered T cells during ACT of PDA. Abrogating TGF{beta} signaling augmented TCR-engineered T cell accumulation in autochthonous and orthotopic PDA models and promoted terminal effector T cells, although this largely required inclusion of a vaccine at the time of T cell transfer. While loss of Tgfbr2 impaired CD103 upregulation, it only modestly impaired donor T cell central, tissue resident, or Tcf1+Slamf6+ stem-like memory T cell formation. These attributes ultimately result in heightened functional capacity and delayed tumor growth. Unexpectedly, however, most tumor-infiltrating engineered T cells failed to differentiate into PD-1+Lag3+ exhausted T cells (TEX) regardless of TGF{beta}R2 expression and despite abundant Msln protein expression by PDA cells. Forcing Msln epitope processing in KPC tumor cells promoted donor T cell accumulation, acquisition of PD-1 and Lag3, increased IFN{gamma} production by TCR-engineered T cells refractory to TGF{beta} and bypassed the vaccine requirement for therapeutic efficacy. Thus, promoting increased antigen processing/presentation by tumor cells while abrogating Tgfbr2 in engineered T cells can sustain donor T cell function in the suppressive TME and enhance the therapeutic efficacy of ACT. Our study supports pursuit of strategies that modulate tumor intrinsic antigen processing while relieving T cell suppression to safely promote the antitumor activity of TCR-engineered T cells.

immunology↗

Biophysical modeling identifies an optimal hybrid amoeboid-mesenchymal phenotype for maximal T cell migration speeds

Despite recent advances in understanding cell migration mechanics, the principles governing rapid T cell movement remain unclear. Efficient migration is critical for antitumoral T cells to locate and eliminate cancer cells. To investigate the upper limits of cell speed, we developed a hybrid stochastic-mean field model of bleb-based cell motility. Our model suggests that cell-matrix adhesion-free bleb-based migration is highly inefficient, challenging the feasibility of cell swimming/adhesion-independent migration as a primary fast motility mode. Instead, we show that T cells can achieve rapid migration by combining bleb formation with adhesion-based forces. Supporting our predictions, our three-dimensional gel experiments confirm that T cells migrate significantly faster under adherent conditions than in adhesion-free environments. These findings highlight the mechanical constraints of T cell motility and suggest that modifying tissue adhesion properties in a controlled manner could enhance immune cell infiltration into tumors. Our computational and experimental work provides insights for optimizing T cell-based immunotherapies. While antifibrotic treatments could alter the tumor microenvironment, indiscriminate reduction of adhesion may not be ideal for T cell infiltration and motility, highlighting the need for targeted antifibrotic strategies.

biophysics↗

Stromal architecture directs early dissemination in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDA) is an extremely metastatic and lethal disease. Here in both murine and human PDA we demonstrate that extracellular matrix architecture regulates cell extrusion and subsequent invasion from intact ductal structures through Tumor-Associated Collagen Signatures (TACS), resulting in early dissemination from histologically pre-malignant lesions and continual invasion from well-differentiated disease. Furthermore, we show that pancreatitis results in invasion-conducive architectures, thus priming the stroma prior to malignant disease. Analysis in novel microfluidics-derived microtissues and in vivo demonstrates decreased extrusion and invasion following focal adhesion kinase (FAK) inhibition, consistent with decreased metastasis. Thus, data suggest that targeting FAK or strategies to re-engineer and normalize tumor microenvironments, may have a role not only in also in very early disease but also for limiting continued dissemination from unresectable disease. Likewise, it may be beneficial to employ stroma targeting strategies to resolve precursor diseases such as pancreatitis in order to remove stromal architectures that increase risk for early dissemination. Impact StatementCollagen architectures in the tumor stroma facilitate dissemination of carcinoma cells from the earliest histologically "pre-malignant" lesions and continue to promote disease spread from well-differentiated PDA.

cancer biology↗

Biophysical modeling of the SARS-CoV-2 viral cycle reveals ideal antiviral targets

Effective therapies for COVID-19 are urgently needed. Presently there are more than 800 COVID-19 clinical trials globally, many with drug combinations, resulting in an empirical process with an enormous number of possible combinations. To identify the most promising potential therapies, we developed a biophysical model for the SARS-CoV-2 viral cycle and performed a sensitivity analysis for individual model parameters and all possible pairwise parameter changes (162 = 256 possibilities). We found that model-predicted virion production is fairly insensitive to changes in most viral entry, assembly, and release parameters, but highly sensitive to some viral transcription and translation parameters. Furthermore, we found a cooperative benefit to pairwise targeting of transcription and translation, predicting that combined targeting of these processes will be especially effective in inhibiting viral production.Competing Interest StatementThe authors have declared no competing interest.View Full Text

systems biology↗

Engineering T cells to enhance 3D migration through structurally and mechanically complex tumor microenvironments

Defining the principles of T cell migration in structurally and mechanically complex tumor microenvironments is critical to understanding sanctuaries from antitumor immunity and optimizing T cell-related therapeutic strategies. To enhance T cell migration through complex microenvironments, we engineered nanotextured platforms that allowed us to define how the balance between T cell phenotypes influences migration in response to tumor-mimetic structural and mechanical cues and characterize a mechanical optimum for migration that can be perturbed by manipulating an axis between microtubule stability and force generation. In 3D environments and live tumors, we demonstrate that microtubules instability, leading to increased Rho pathway-dependent cell contractility, promotes migration while clinically used microtubule-targeting chemotherapies profoundly decrease effective migration. Indeed, we show that rational manipulation of the microtubule-contractility axis, either pharmacologically or through genome engineering, results in engineered T cells that more effectively move through and interrogate 3D matrix and tumor volumes. This suggests that engineering cells to better navigate through 3D microenvironments could be part of an effective strategy to enhance efficacy of immune therapeutics.

cancer biology↗