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Biology subjects

Gonzalez, Y.

Publications and source records attributed to Gonzalez, Y..

3 recordsLinked to original sources

Targeting Monoallelic CREBBP/EP300 Mutations in Germinal Center-Derived B-Cell Lymphoma with a First-in-Class Histone Acetyltransferase Activator

Germinal center B-cell lymphomas frequently exhibit monoallelic loss-of-function mutations in the histone acetyltransferases CREBBP and p300, which contribute to lymphoma development, disrupt normal germinal center biology, and promote immune evasion. This study evaluates YF2, a histone acetyltransferase activator that increases CREBBP/p300 activity, as a potential therapeutic approach for B-cell lymphoma. YF2 binds the bromodomain of CREBBP/p300, increasing their auto-acetylation and enzymatic activity. It also induces cytotoxicity in B-cell lymphoma cell lines, with a stronger response in those carrying CREBBP/EP300 mutations. Additionally, YF2 increases the acetylation of key CREBBP/p300 substrates, including H3K27, p53, and BCL6, leading to enhanced apoptosis and altered B-cell diTerentiation. YF2 is well tolerated in vivo and extends survival in both cell line- and patient-derived xenograft mouse models. Moreover, YF2 exposure upregulates antigen-presentation markers and reshapes the immune microenvironment, strengthening responses to immune checkpoint blockade. Taken together, these findings support pharmacologic activation of CREBBP/p300 with YF2 as a compelling therapeutic strategy for B-cell lymphoma. SignificanceYF2 stimulates CREBBP/p300 activity to normalize B-cell diTerentiation and enhance immune recognition, oTering a potential approach to limit lymphoma progression and strengthen immunotherapy responses.

cancer biology↗

Micronutrient Optimization Using Design of Experiments Approach in Tissue Engineered Articular Cartilage for Production of Type II Collagen

Tissue Engineering of cartilage has been hampered by the inability of engineered tissue to express native levels of type II collagen in vitro. Inadequate levels of type II collagen are, in part, due to a failure to recapitulate the physiological environment in culture. In this study, we engineered primary rabbit chondrocytes to express a secreted reporter, Gaussia Luciferase, driven by the type II collagen promoter, and applied a Design of Experiments approach to assess chondrogenic differentiation in micronutrient-supplemented medium. Using a Response Surface Model, 240 combinations of micronutrients absent in standard chondrogenic differentiation medium, were screened and assessed for type II collagen expression. Five conditions predicted to produce the greatest Luciferase expression were selected for further study. Validation of these conditions in 3D aggregates identified an optimal condition for type II collagen expression. Engineered cartilage grown in this condition, showed a 170% increase in type II collagen expression (Day 22 Luminescence) and in Youngs tensile modulus compared to engineered cartilage in basal media alone. Collagen cross-linking analysis confirmed formation of type II-type : II collagen and type II-type : IX collagen cross-linked heteropolymeric fibrils, characteristic of mature native cartilage. Combining a Design of Experiments approach and secreted reporter cells in 3D aggregate culture enabled a high-throughput platform that can be used to identify more optimal physiological culture parameters for chondrogenesis.

cell biology↗

Examining multiple cellular pathways at once using multiplex hextuple luciferase assaying

Sensitive simultaneous assessment of multiple signaling pathways within the same cells requires orthogonal reporters that can assay over large dynamic ranges. Luciferases have arisen as possible genetically encoded candidates due to their sensitivity, versatility, and cost-effectiveness. Here, we expanded luciferase multiplexing in post-lysis endpoint luciferase assays from two towards six. Light emissions are distinguished by a combination of distinct substrates and emission spectra deconvolution. Using synthetic assembly cloning, all six luciferase reporter units are stitched together into one plasmid; facilitating delivery of all reporter units through a process we named solotransfection, minimizing experimental errors. We engineered a multiplex hextuple luciferase assay to probe pathway fluxes through five transcriptional response elements against a control constitutive promoter. We were able to monitor the effects of siRNA, ligand, and chemical compound treatments on their target pathways along with the four other probed cellular pathways. We demonstrate the effectiveness and adaptiveness of multiplex luciferase assaying, as well as its broad application across different research fields.

molecular biology↗