Reaction Biology (Germany)

Technological systems increasingly shape how people live, love, and relate-often revealing hidden social pressures and vulnerabilities.This Spotlight traces how digital and cultural infrastructures reorganize everyday life: a hyper-competitive housing market that pushes students toward self-marketing and extreme compromises; growing "app fatigue" that drives singles back toward face-to-face dating; and the continued appeal of biography as a distinctly human form that resists algorithmic speed and simplification.The collection also confronts technology's darker edges, including evidence that addictive patterns of digital use (more than screen time alone) correlate with youth mental health risks, and the severe harms enabled by online coercion networks targeting children.Curated in JOSHA's interdisciplinary spirit, these pieces invite readers to see technology not as a neutral backdrop, but as a force reshaping intimacy, opportunity, attention, and safety.

Dysregulated cellular signaling pathways involving protein kinases are critically implicated in cancer development. Consequently, protein kinases have emerged as key targets for novel anticancer therapies. A range of kinase inhibitors, including small molecules and monoclonal antibodies, has been developed. Although early strategies focused on achieving high specificity to minimize adverse effects, resistance to these targeted therapies has limited their effectiveness. As a result, broader-spectrum inhibitors that act on multiple cancer-related kinases are now considered more promising therapeutic options. We developed twenty-five new pyrrolopyrimidine derivatives featuring diverse substitution patterns to assess their potential as small-molecule inhibitors of the protein kinases CLK4 and HER2, both of which are significant therapeutic targets in metastatic breast cancer. Pyrrolopyrimidine derivatives were synthesized and purified by column chromatography. Their protein kinase inhibitory activity was evaluated through a radioactive ATPcompetition assay. The compounds were obtained through a multi-step synthetic procedure, concluding with substitution reactions. The effects of different substituents on the inhibitory properties of the observed protein kinases are analyzed and discussed. Aniline-substituted derivatives exhibited the most potent activities, which were further modulated by N-substituted pyrroles. Consequently, we identified both selective and dual inhibitors of the target kinases, demonstrating activity in the nanomolar range.

Abstract Protein kinases are essential for the regulation of many biological processes, e.g. proliferation, differentiation, migration, and apoptosis. Deregulated kinase activity is observed in tumor cells and altered activity of specific kinases is essential for development and progression of cancer and other diseases. Consequently, regulation of protein kinase activity became a target for therapeutic intervention. Intensive research resulted in the development of many small molecule kinase inhibitors (SMI) being clinically approved as targeted therapies. Functional biochemical in-vitro assays are essential requirements to assess SMIs effects on target kinase activity after validation of specific kinases being molecular drivers of a pathological condition. Only limited information is gained by monitoring the interaction of kinase and compound in pure binding assays, but more conclusive data can be generated by in-vitro kinase activity assays. However, the relevance of results from both approaches depends on how well the assay setup responds to the mode-of-action of the compounds. Recombinant proteins and generic substrates are well established in development of protein kinase assays due to cost and technical feasibility considerations. Especially some generic substrates are highly artificial e.g. the commonly used Tyrosine-kinase substrate Poly(Glu/Tyr)4:1 and may be considered as phosphate group acceptors only. However, such generic substrates have successfully been used for development of numerous clinically approved SMIs. Other kinases however are not compatible with generic substrates and can only be established using less artificial substrates or even require their respective physiological in-vivo substrate for in-vitro activity. These kinases include several members of the RAF and MAPK family. Functional in-vitro assay using a generic substrate are rarely replaced by physiological substrate due to more complex assay conditions and increased cost for drug screening. We compared biochemical in-vitro kinase activity assays for the LIM kinases, LIMK1 and LIMK2, using either generic substrates or the published physiological substrates, CFL1 and CFL2. We further evaluated these results by comparing them in different assays, using radiometric and luminescent read-out technologies. Several published LIMK inhibitors displayed significant differences in the relative potency when tested with generic or physiological substrates. Generic substrates for biochemical in-vitro kinase activity assays in preclinical drug development have been well established and successfully applied in the past. However, our data indicate, that the choice of a more physiological substrate should be considered carefully, as it might significantly increase the relevance and therefore value of the results obtained from early-stage compound screening. Citation Format: Robert Torka, Andreas Gericke, Frank Totzke, Carolin Heidemann-Dinger, Constance Rademann, Thomas Weber, Daniel Mueller. Apparent potency of small molecule inhibitors is influenced by the choice of substrate in LIMK biochemical in-vitro kinase activity assays [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6966.

Abstract The recent advances in cellular immunotherapies have revolutionized the treatment options for hematological malignancies. Among others, genetically engineered T cells to express chimeric antigen receptors targeting CD19 have shown clinical success in patients with B cell malignancies. However, depending on the study design only one to two thirds of the patients experience a complete response upon CD19 CAR T cells treatment. Antigen escape, immune suppressive microenvironment, CAR T cell dysfunction as well as lack of CAR T cell persistence have been discussed to be reasons for the lack of sustained therapy response. Well established models for the preclinical evaluation of cellular therapies are needed for the evaluation of next generation CAR T cells as well as novel combination therapies. Here, we describe a xenograft animal model of human acute lymphoblastic leukemia (NALM-6 cells) with a suboptimal treatment response to human CD19 CAR T cells from three different donors. First, the activation status and memory phenotype of the CAR T cells from the different donors was characterized by flow cytometry and the anti-tumoral efficacy of the CD19 CAR T cells was evaluated in an in vitro co-culture killing assay using luciferase expressing NALM-6 cells. Next, CD19 CAR T cells from three donors were injected in NALM-6_luc tumor bearing animals. The tumor growth was monitored by bioluminescence imaging and the phenotype of the transferred CAR T cells was checked by flow cytometry. The frequency of memory T cells differed between the donors whereas the T cells from all donors exhibited all low expression of activation markers. In vitro, all three donors showed high and comparable anti-tumoral killing efficacy independent of their memory status. In vivo, CD19 CAR T cells from all three donors delayed the tumor growth significantly although none of the animals had a complete remission. In line with the individual memory status of the CAR T cells prior to infusion, there were slight differences in the kinetics of the anti-tumoral response. The flow cytometric analysis revealed that the transferred CAR T cells were almost absent in the peripheral blood and spleen whereas for individual animals tumor cells and highly activated CAR T cells were detectable in the bone marrow of the animals. In summary, the NALM-6_luc xenograft model is a value tool for evaluating next generation cellular therapies and novel combination strategies to overcome the current limitations of cellular therapies. Citation Format: Philipp Metzger, Carla N. Castro, Jonas F. Hummel, Maria Silvia Roman Azcona, Dinu Antony, Claudio Mussolino, Daniel Zurr, Swetlana Adamsky, Holger Weber. Donor-dependent anti-tumoral efficacy of human CD19 CAR T cells in a leukemic xenograft mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4020.

Abstract We sought to screen all FDA approved, cancer-indicated, kinase targeting drugs using the gold standard radiometric biochemical activity assay (HotSpot) against the largest collection of kinases in the world (>100 drugs against 735 total kinases including 395 wild type and 340 mutants). One of these drugs, mitapivat, is an activator of Pyruvate Kinase. Here, we show mitapivat-driven biochemical inhibition of several, but not all, mutants of c-KIT. We also observed the equal and opposite phenomenon whereby many ATP-competitive kinase inhibitors demonstrate biochemical activation of certain kinases, several of which seem particularly susceptible to the effect. Previous work by other investigators (at Genentech and the Rosen lab, MSKCC) demonstrated that PLX4720 (precursor to Vemurafenib) paradoxically activated wild type BRAF, but not BRAF mutants, by driving dimerization of the kinase in drug concentrations insufficient to inhibit both members of the dimerized pair. Our data suggests this phenomenon may be more widespread than previously appreciated and fully observable in vitro. Such paradoxical activation could be driving both toxicities and inefficacy against cancers expressing some of these activatable kinases. This information could suggest novel opportunities for combination therapy and improve outcomes by contraindicating certain medication from use based on tumor expression profile. Citation Format: Christian M. Loch, Mia Eason, Shuguang Liang, Alison Goupil, Anthony Acinapura, Jamie Purcell, Maia Domiguez. Paradoxical activation of kinases occurs directly with ATP-competitive kinase inhibitors and is observable biochemically at physiologically relevant drug concentrations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6489.

Abstract Over the recent years, knowledge of RNA modifications and their regulation has expanded extensively, providing novel insights and strategies to explore potential therapeutics for pathogenesis of various diseases, including cancer. Several chemical modifications in RNA have been identified so far, among these N6-methyladenosine (m6A) modification is the most abundant and well-studied epitranscriptomic marker found in mRNA and long noncoding RNA. Abnormal m6A expression is proven to be associated with tumorigenesis, cancer stemness and drug resistance of cancers. Methylation in 6-Adenosin of RNA is a dynamic and reversible process tightly regulated by its writer, m6A methyltransferase complex and erasers, FTO and ALKBH5. m6A methyltransferase complex contains METTL3-METTL14-WTAP as core components. METTL3 is the catalytic component, which is activated by heterodimer formation with METTL14. High METTL3 expression is found in several cancers such as breast, lung, liver, gastric, colorectal, AML and a METTL3 catalytic inhibitor is found to delay AML progression in mouse models. Protein that binds RNA m6A modification to execute it signaling are known as m6A readers. Readers are categorized into three main classes, YTH domain proteins, IGF2 mRNA-binding proteins and heterogeneous nuclear ribonucleoproteins. YTH family readers are found to have oncogenic roles in several cancers including AML, breast, lung, CRC and glioblastoma. Recent studies suggest inhibition of m6A binding of individual YTH family proteins is a promising therapeutic strategy however, potent inhibitors are yet to be identified. This poster summarizes current assays we have developed to facilitate cancer therapeutic discovery in m6A related protein targets. We present development and validation of an assay suitable identify in METTL3 catalytic inhibitors using our proprietary hotspot technology. We also show development of HTRF based biochemical assays for all five YTH family protein YTHDF1-3 and YTHDC1-2, to screen for molecules that disrupt protein-m6A interaction. We further study the selectivity of an FDA approved drug Tegaserod, a reported YTHDF1 inhibitor by a structure based virtual screening, between YTH family proteins. Citation Format: Safnas F. AbdulSalam, Sung Won Oh, Brenna P. Lee, Joseph J. Ferry, John R. Ries, Kurumi Y. Horiuchi. Development of biochemical screening assays to facilitate drug discovery in RNA m6A modification regulators [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4417.

The WRKY transcription factor (TF) belongs to one of the major plant protein superfamilies. The WRKY TF gene family plays an important role in the regulation of transcriptional reprogramming associated with plant stress responses. Change in the expression patterns of WRKY genes or the modifications in their action; participate in the elaboration of numerous signaling pathways and regulatory networks. WRKY proteins contribute to plant growth, for example, gamete formation, seed germination, post-germination growth, stem elongation, root hair growth, leaf senescence, flowering time, and plant height. Moreover, they play a key role in many types of environmental signals, including drought, temperature, salinity, cold, and biotic stresses. This review summarizes the current progress made in unraveling the functions of numerous WRKY TFs under drought, salinity, temperature, and cold stresses as well as their role in plant growth and development.

Over the last three decades, the human brain and its role in determining behavior have been receiving a growing amount of attention in academia as well as in society more generally. Neuroscientific explanations of human behavior or other phenomena are often especially appealing to lay people. Therefore, neuroscientific explanations that can affect individuals, groups, or social relations in general should be formulated in a careful and responsible way. One field in which especially feminist scholars request more caution is the neuroscientific examination of sex/gender differences. Feminist scholars have described various ways in which sexist bias might be present in neuroscientific research on sex/gender differences. In this context, they coined the term "neurosexism" to describe the entanglement between neuroscientific work and sexist ideology, and "neurofeminism" as a response to that. Here, we aim to give an overview over the contemporary neurofeminist literature. In the first part, common levels of analysis in the neurofeminist literature are presented and the research level is explored in more detail. In the second part, some common developments in more recent neurofeminist scholarship are discussed. For this, we review recent publications with the aim to provide neuroscientists with a solid understanding of neurofeminist criticism so that they may evaluate neuroscientific claims about on sex/gender differences from this critical perspective.

Abstract Epigenetic modifications are dynamic and reversible processes that regulate gene expression without altering the underlying sequence of the DNA. Gene expression is instead controlled by modification to the chromatin including DNA methylation, histone modifications, and chromatin remodeling. The proteins that perform these epigenetic modifications can be divided into three classes: writers, which perform the modifications; readers, which recognize the modifications; and erasers, which remove the modifications. While essential for normal cellular function, abnormal expression or alteration of the proteins involved in epigenetic regulation can lead to disease, such as cancer. As a result, epigenetic modifiers present attractive targets for the discovery and development of novel therapeutics. At Reaction Biology we offer a suite of services to enable epigenetic drug including the largest panel for epigenetic screening and profiling in the industry and biochemical and biophysical technologies to evaluate inhibition, potency, target occupancy, and even binding modes. Here we highlight our biophysical platform surface plasmon resonance (SPR) using the epigenetic target PRMT5 as an example. SPR was used to measure the binding kinetics of several small molecule inhibitors of PRMT5 and explore their distinct binding modes. Citation Format: Rebecca Eells, Lynn K. Baker, Christopher Bray, Haiching Ma. Probing PRMT5 inhibitors with distinct binding modes using surface plasmon resonance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2921.

Abstract The small GTPase, KRAS, is a known oncogene and a desirable drug target due to prevalence of mutations with poor disease prognosis. The absence of good druggable binding pockets has made modulator compound discovery challenging and unsuccessful. Identification of new inhibitor target sites has led to the resurgence of interest in KRAS drug discovery. To facilitate drug discovery activities targeting KRAS/MAPK pathway, we have produced the full spectrum of pathway proteins including kinases, wild type and mutated KRAS, guanine nucleotide exchange factor and effectors. This poster will summarize our most recent assay development efforts for biochemical and biophysical assays for these targets. Citation Format: Ekaterina Kouznetsova, Lauren McCauley, Elaine Steinke-Neal, Timothy Sullivan, Louis Primavera, Rebecca Eells, Haiching Ma. A versatile assay suite for the discovery of new KRAS pathway inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2987.