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Adams, J.

Publications and source records attributed to Adams, J..

At least 19 recordsLinked to original sources

Random mtDNA mutagenesis maps genotype-phenotype associations across metabolic contexts and lineages

Mitochondrial DNA (mtDNA) mutations cause inherited disease, accumulate with age, and recur in tumors, yet their effects remain unresolved because existing models interrogate one engineered allele at a time. We developed mtDIVE, a random C[->]T mutagenesis platform for pooled mitochondrial forward genetics in human epithelial cells and zebrafish embryos. mtDIVE generates genotypes ranging from single substitutions to >100 mutations per molecule, impairs respiration, and causes lineage-specific developmental delay. Coupling single-cell transcriptomics with mtDNA genotyping revealed that selection on mutant genomes and their transcriptional consequences depend on metabolic state and developmental lineage. Obligate OXPHOS eliminates highly mutated cells by apoptosis, whereas glycolytic conditions promote their competitive displacement. Individual loci exert modest but non-redundant effects that predict cell state beyond aggregate mutation burden, and cancer-recurrent variants are enriched among mutations linked to reduced mitochondrial transcription. Thus, mtDIVE links mtDNA genotypes to cellular phenotypes, separating the consequences of mutation identity from mutational load.

genomics↗

Vibrotactile transcutaneous auricular vagus nerve stimulation (taVNS) during working memory: convergent electrophysiological evidence for cortical efficiency

Background: Working memory, the cognitive ability to maintain and manipulate a finite amount of information, is fundamental in reasoning, learning, and decision-making. Working memory erodes in conditions from Alzheimer's disease to stroke to healthy aging. Transcutaneous auricular vagus nerve stimulation (taVNS) is a promising neuromodulation method for improving working memory. By stimulating the auricular branch of the vagus nerve, taVNS is thought to engage ascending arousal systems such as the locus coeruleus-norepinephrine (LC-NE) system. However, the physiological link between LC-NE system modulation via taVNS and improved working memory remains largely unknown. This mechanistic gap limits the rational optimization of the stimulation protocol and the identification of the cognitive functions and patient populations that are likely to benefit. Objective: We test two competing hypotheses for how taVNS may improve working memory: sensory amplification or enhancement of cortical efficiency. The sensory-amplification hypothesis predicts increased cortical responses to stimuli, whereas the cortical-efficiency hypothesis predicts reduced cortical responses. Methods: Twenty healthy adults completed N-back working memory tasks during three counterbalanced sessions: baseline, active vibrotactile taVNS (vtaVNS), and sham stimulation, while we simultaneously recorded electroencephalography, electrocardiography, eye-tracking, and behavioral responses. To study the effect of vtaVNS on neuronal activity, we also recruited 20 patients with epilepsy undergoing invasive monitoring. Of these, 19 fully completed the spatial working-memory task. We quantified cortical responses to visual stimuli using event-related potentials (ERPs) in scalp EEG and high-gamma activity in intracranial local field potentials. To examine prediction of the cortical-efficiency hypothesis, we further explored the effect of vtaVNS on distance to criticality and heartbeat-evoked potentials. Results: Active vtaVNS reduced both scalp-recorded visual ERP and high-gamma response in temporal cortices, relative to sham stimulation. Moreover, smaller visual event-related potentials were associated with successful encoding during the most demanding working-memory condition (i.e., 4-back task). Exploratory analyses showed that vtaVNS shifted cortical dynamics closer to criticality. Conclusion: Our results converge on the conclusion that vtaVNS does not uniformly amplify cortical responses to external stimuli. Instead, vtaVNS enhances cortical efficiency, supporting more effective allocation of cognitive resources between exteroceptive and mnemonic processes. These findings provide a framework for predicting when taVNS will be most beneficial and for optimizing stimulation protocols across cognitive and clinical applications.

neuroscience↗

AGROtools: A comprehensive modular cloning toolset for Agrobacterium strain engineering

Agrobacterium-mediated transformation is a cornerstone of plant genetic engineering, yet many crops remain recalcitrant to transformation and its efficiency is highly species- and genotype-dependent. The limited diversity of disarmed agrobacterial strains available for biotechnology, and the technically challenging workflows typically required for strain modification, constrain efforts to develop improved plant transformation platforms. Here, we describe the development of AGROtools-a versatile, expandable, and user-friendly modular cloning plasmid collection comprising more than 75 individual components, that is designed to simplify genetic engineering of agrobacteria. Constructs assembled with this toolkit couple visual reporters with selectable and counterselectable markers to facilitate identification of recombinant clones, thereby reducing reliance on PCR-based screening. We constructed and tested reporter cassettes that are functional across diverse agrobacterial strains and genomic contexts. By linking a visual reporter combinatorially with various antibiotic resistance markers and orthogonal site-specific recombinase recognition sequences, AGROtools can enable marker removal and recycling for up to four successive genomic modifications. We demonstrate the utility of AGROtools by disarming 10 novel wild-type strains, and accomplishing serial modifications within individual strain backgrounds. In addition to conventional recA-mediated homologous recombination, the collection incorporates components for applying contemporary strain engineering approaches, including CRISPR/dCas9 base editing, INTEGRATE-mediated targeted insertion, and phage-derived recombineering systems. Constructs can be assembled and deployed rapidly, enabling isolation of strains carrying an intended modification in less than two weeks. AGROtools provides a broadly applicable resource for accelerating strain development and genetic studies in agrobacteria, with potential to advance plant biotechnology by aiding improvement of disarmed strains.

plant biology↗

The basal cell state maintains pancreatic cancers by controlling an immunosuppressive circuit

Intra-tumoral heterogeneity is a cardinal feature of solid tumors, yet how distinct cancer cell states functionally contribute to malignant and stromal diversity in situ remains poorly understood. Using mouse models to lineage-trace or genetically ablate the two predominant cancer cell states in autochthonous pancreatic ductal adenocarcinoma (PDAC), we discover that basal cancer cells are highly plastic, whereas classical cancer cells exhibit limited plasticity. Strikingly, ablation of the basal, but not the classical, state induced rapid and durable tumor collapse, driven by loss of immunosuppressive cancer-associated fibroblasts, macrophage repolarization, and reprogramming of the tumor cytokine milieu, culminating in tumor destruction by cytotoxic lymphocytes. Knockout of a single cytokine, GM-CSF, specifically in basal cells recapitulated macrophage repolarization and lymphocyte recruitment observed upon basal state ablation and shrank tumors. These results reveal the basal cell state controls an immunosuppressive cell circuit critical for PDAC maintenance, motivating therapeutic targeting of the basal cells.

cancer biology↗

Disordered N-terminal region of CLK1 oligomerizes for recruitment to nuclear substructures and splicing function

Cdc2-like kinase 1 (CLK1) phosphorylates the serine-arginine (SR) proteins, a family of nuclear factors essential for mRNA splicing. The ability of CLK1 to recognize and efficiently modify SR proteins is strictly dependent on a lengthy, disordered N-terminus flanking its kinase domain. In addition to stimulating phosphorylation, this 150-residue extension also induces large oligomer formation in CLK1 but it is unclear whether said structure is important for catalytic or cellular function. We identified a subset of N-terminal residues that, upon removal, impairs oligomerization of CLK1 but does not abolish phosphorylation of the SR protein SRSF1. Despite robust phosphorylation, CLK1 lacking these high-order oligomerization sequences cannot effectively enter nuclear speckles and release SRSF1. This inability to mobilize CLK1 has detrimental effects on the alternative splicing of the CLK1 gene, severing an important, autoregulatory mechanism that controls active cellular levels of the kinase. Such findings indicate that whereas a limited group of residues in the N-terminus activates the kinase domain for SR protein phosphorylation, sequences that induce oligomerization direct CLK1 to the proper subnuclear structures for splicing function.

biochemistry↗

Human and generative AI integrate visual cues differently in a shape completion task

In amodal completion observers perceive complete objects despite partial occlusion. When two object parts are divided by an occluder, completion can result in perceiving one or two objects. This phenomenon involves both lower-level cues (e.g., symmetry, contour continuity) and higher-level cues (e.g., prior knowledge). Experiment 1 investigates how occluder size, familiarity, and symmetry affect human completions using a drawing task. Narrow occluders and asymmetry promote single-shape completions, while familiarity and (global) symmetry promote two-shape interpretations. Good continuation emerges as the strongest cue, with symmetry and familiarity playing increasingly important roles as occluder width increases. Experiment 2 compares human performance with three state-of-the-art generative AI models. Models often generated creative but non-compliant outputs, altering even unoccluded regions. We restricted analysis to instruction-following generations, identified through ratings by naive observers. Among compliant outputs, models showed some human-like biases (e.g., more two-shape completions for wide occluders), but failed with higher-level cues. They did not use symmetry to guide completions and showed reversed familiarity effects. Our findings highlight differences between human and AI completions. Humans integrate low- and high-level cues, whereas compliant outputs from the AI models rely primarily on low-level pattern continuation. Current AI models lack the flexible integration of multiple representational levels that characterize human perception. This work establishes an analytical framework for evaluating whether next-generation models achieve more human-like visual reasoning. HighlightsO_LIHumans see one or two objects behind occluders using geometric and semantic cues. C_LIO_LIHuman drawings and generative AI completions show how different cues modulate perception C_LIO_LIGood continuation dominates human and AI shape completions C_LIO_LISymmetry and familiarity guide humans, but not instruction-following AI outputs C_LIO_LIHumans integrate multiple levels; instruction-following AI engages lower-level-processing. C_LI

neuroscience↗

A hormonally regulated gating mechanism controls EMT timing to ensure progenitor cell specification occurs prior to epithelial breakdown

Epithelial-to-mesenchymal transitions (EMTs) are essential for morphogenesis, converting static epithelial cells into migratory mesenchymal cells. As EMT disrupts epithelial barriers, its timing must be tightly regulated during development. We investigated this regulation in the Drosophila posterior embryonic midgut, where the GATA transcription factor Serpent (Srp) drives a collective partial EMT in the principal midgut epithelial cells (PMECs). Srp is expressed well before PMEC-EMT initiation and is also required for an earlier event: the specification and delamination of endoblasts, which give rise to different midgut lineages including adult midgut progenitors (AMPs). Here we identify the steroid hormone ecdysone as a temporal cue that triggers PMEC-EMT. Although Srp activates and represses numerous genes during early stages of midgut development, including polarity regulators such as crumbs (crb), the removal of polarity proteins and E-Cadherin from the membrane of PMECs only properly occurs in the presence of ecdysone signalling. This suggests that Srp primes cells transcriptionally for EMT, which proceeds only once polarity and adhesion proteins are downregulated post-translationally. When PMECs undergo a premature EMT, this leads to a reduction in the number of progenitor cells, suggesting that maintaining epithelial integrity until after endoblasts are selected is crucial for early fate decisions. These findings reveal that ecdysone functions as a EMT gatekeeper, ensuring that EMT is temporally restricted to occur only after progenitor specification, and in coordination with other developmental processes. More broadly, our work shows that in this context, transcriptional priming of EMT can be uncoupled from its execution, which is post-translationally triggered by hormonal signals. Given the conserved role of nuclear steroid hormone receptors as GATA co-factors and their association with poor prognosis in cancer, this may represent a broader strategy by which systemic cues regulate EMT in development and cancer.

developmental biology↗

Heme drives cardiac endothelial senescence in sepsis via STING activation

Sepsis-induced cardiac dysfunction is a major contributor to sepsis-related mortality, and many patients continue to experience long-term cardiac complications after recovery. Here, we demonstrate that cardiac senescence is a key feature of sepsis-associated cardiac dysfunction, with endothelial cells identified as the predominant senescent population in septic cardiac tissue. Yet, the pathogenic drivers of endothelial senescence in sepsis remain poorly characterized. Among potential mediators, we found that elevated levels of heme, a byproduct of hemolysis, strongly correlate with increased endothelial senescence and impaired cardiac function. Mechanistic studies revealed that heme acts as a novel ligand for STING, exacerbating bacterial infection induced STING polymerization and activation, thereby promoting endothelial senescence. Notably, either STING inhibition or enhanced heme clearance via increased hemopexin expression significantly alleviated cardiac endothelial senescence and facilitated cardiac functional recovery in septic mice. These findings identify heme as a critical pathogenic driver of endothelial senescence and highlight heme clearance as a promising therapeutic strategy for mitigating sepsis induced cardiac dysfunction.

cell biology↗

AAV-mediated ARSA replacement for the treatment of Metachromatic Leukodystrophy

Metachromatic leukodystrophy (MLD) is an autosomal recessive neurodegenerative disorder caused by mutations in the arylsulfatase A (ARSA) gene, resulting in lower sulfatase activity and the toxic accumulation of sulfatides in the central and peripheral nervous system. Children account for 70% of cases and become progressively disabled with death occurring within 10 years of disease onset. Gene therapy approaches to restore ARSA expression via adeno-associated viral vectors (AAV) have been promising but hampered by limited brain biodistribution. We report the development of a novel capsid AAV.GMU01, demonstrating superior biodistribution and transgene expression in the central nervous system of non-human primates (NHPs). Next, we show that AAV.GMU01-ARSA treated MLD mice exhibit persistent, normal levels of sulfatase activity and a concomitant reduction in toxic sulfatides. Treated mice also show a reduction in MLD-associated pathology and auditory dysfunction. Lastly, we demonstrate that treatment with AAV.GMU01-ARSA in NHPs is well-tolerated and results in potentially therapeutic ARSA expression in the brain. In summary, we propose AAV.GMU01-ARSA mediated gene replacement as a clinically viable approach to achieve broad and therapeutic levels of ARSA.

neuroscience↗

Transcriptional stochasticity reveals multiple mechanisms of long noncoding RNA regulation at the Xist - Tsix locus

Long noncoding RNAs (LncRNAs) are increasingly recognized as being involved in human physiology and diseases, but there is a lack of mechanistic understanding for the majority of lncRNAs. We comparatively tested proposed mechanisms of antisense lncRNA regulation at the X-chromosome Inactivation (XCI) locus. We find that due to stochasticity in transcription, different mechanisms based on the act of transcription regulate Xist and Tsix at different levels of nascent transcription. At medium levels, RNA polymerases transcribe Xist and Tsix on each strand at the same transcription site and deposit significant amounts of the histone mark H3K36me3, which inhibits Xist. At high levels of nascent transcription, many RNA polymerases transcribe Xist or Tsix resulting in transcriptional interference. Therefore, lncRNA expression variability is not just a quirk of transcription but an important aspect of regulation that allows multiple mechanisms to be employed by the same gene locus within the same cell population.

systems biology↗

SSTR2-targeted theranostics in hepatocellular carcinoma

(1) BackgroundWhile the clinical use of radiolabeled somatostatin analogs is established in neuroendocrine tumors, there is significant interest in expanding their use for other somatostatin receptor 2 (SSTR2)-expressing cancers. This study investigates the utility of SSTR2-targeted theranostics in hepatocellular carcinoma (HCC); (2) MethodsWe measured SSTR2 expression in HCC cell lines and clinical samples using qRT-PCR, Western blot, and a public dataset. We evaluated [67Gallium]Ga-DOTATATE uptake, tested [177Lutetium]Lu-DOTATATE cytotoxicity, and assessed [68Gallium]Ga-DOTATATE tumor targeting in HCC animal models and a patient via PET/CT; (3) ResultsSSTR2 expression was confirmed in HCC cell lines and clinical samples. Radioligand uptake studies validated SSTR2-mediated [67Gallium]Ga-DOTATATE uptake, and [177Lutetium]Lu-DOTATATE treatment reduced cell proliferation. [68Gallium]Ga-DOTATATE PET/CT scans detected tumors in animal models and spinal metastases in a patient with HCC; (4) ConclusionThese findings suggest for the first time that SSTR2-based theranostics could have strong implications for detection and treatment of HCC. Simple SummaryThis study investigates the use of SSTR2-targeted theranostics, combining diagnostic and therapeutic approaches, in hepatocellular carcinoma (HCC). We confirmed significant SSTR2 expression in HCC cells and patient samples, showing that radiolabeled compounds such as [67Ga]Ga-DOTATATE and [177Lu]Lu-DOTATATE, commonly used in neuroendocrine tumors, could also target HCC. In preclinical models and a patient case, PET/CT imaging and treatments demonstrated effective tumor detection and shrinkage. These findings suggest that SSTR2-targeted theranostics could offer a novel, targeted method for diagnosing and treating HCC, potentially improving outcomes for patients with this challenging cancer.

cancer biology↗

Induction of Meiosis from Human Pluripotent Stem Cells

An in vitro model of human meiosis would accelerate research into this important reproductive process and development of therapies for infertility. We have developed a method to induce meiosis starting from male or female human pluripotent stem cells. We demonstrate that DNMT1 inhibition, retinoid signaling activation, and overexpression of regulatory factors (anti-apoptotic BCL2, and pro-meiotic HOXB5, BOLL, or MEIOC) rapidly activates meiosis, with leptonema beginning at 6 days, zygonema at 9 days, and pachynema at 12 days. Immunofluorescence microscopy shows key aspects of meiosis, including chromosome synapsis and sex body formation. The meiotic cells express genes similar to meiotic oogonia in vivo, including all synaptonemal complex components and machinery for meiotic recombination. These findings establish an accessible system for inducing human meiosis in vitro.

synthetic biology↗

Near infrared fluorescent nanosensors for high spatiotemporal oxytocin imaging

Oxytocin is a neuropeptide involved in regulating social and emotional behavior. Current techniques for oxytocin imaging are generally limited in spatial and temporal resolution, real-time imaging capacity, selectivity for oxytocin over vasopressin, and application in young and non-model organisms. To address these issues, we developed a method to evolve purely synthetic molecular recognition for oxytocin on the surface of near-infrared fluorescent single-walled carbon nanotubes (SWCNT) using single-stranded DNA (ssDNA). The best-performing nanosensor nIROT-SELEC reversibly undergoes up to a 172% fluorescence increase in response to oxytocin with micromolar dissociation, nanomolar limit of detection, and and high selectivity over oxytocin analogs, receptor agonists and antagonists, and co-released neurochemicals. We next demonstrated the versatility of nIROT-SELEC by performing live imaging of synaptic evoked oxytocin released in acute brain slices of mice and prairie voles. Our method for high throughput evolution of neuropeptide nanosensors holds promise to enable synaptic scale visualization of neuropeptide signaling in the brain cross different species and developmental stages, to advance the study of neurochemical signaling for its role in both health and disease.

neuroscience↗

Does Vibrotactile Stimulation of the Auricular Vagus Nerve Enhance Working Memory? A Behavioral and Physiological Investigation

BackgroundWorking memory is essential to a wide range of cognitive functions and activities. Transcutaneous auricular VNS (taVNS) is a promising method to improve working memory performance. However, the feasibility and scalability of electrical stimulation are constrained by several limitations, such as auricular discomfort and inconsistent electrical contact. ObjectiveWe aimed to develop a novel and practical method, vibrotactile taVNS, to improve working memory. Further, we investigated its effects on arousal, measured by skin conductance and pupil diameter. MethodThis study included 20 healthy participants. Behavioral response, skin conductance, and eye tracking data were concurrently recorded while the participants performed N-back tasks under three conditions: vibrotactile taVNS delivered to the cymba concha, earlobe (sham control), and no stimulation (baseline control). ResultsIn 4-back tasks, which demand maximal working memory capacity, active vibrotactile taVNS significantly improved the performance metric d compared to the baseline but not to the sham. Moreover, we found that the reduction rate of d with increasing task difficulty was significantly smaller during vibrotactile taVNS sessions than in both baseline and sham conditions. Arousal, measured as skin conductance and pupil diameter, declined over the course of the tasks. Vibrotactile taVNS rescued this arousal decline, leading to arousal levels corresponding to optimal working memory levels. Moreover, pupil diameter and skin conductance level were higher during high-cognitive-load tasks when vibrotactile taVNS was delivered to the concha compared to baseline and sham. ConclusionOur findings suggest that vibrotactile taVNS modulates the arousal pathway and could be a potential intervention for enhancing working memory. HighlightsO_LIVibrotactile stimulation of the auricular vagus nerve increases general arousal. C_LIO_LIVibrotactile stimulation of the auricular vagus nerve mitigates arousal decreases as subjects continuously perform working memory tasks. C_LIO_LI6 Hz Vibrotactile auricular vagus nerve stimulation is a potential intervention for enhancing working memory performance. C_LI

bioengineering↗

Predicting Serotonin Detection with DNA-Carbon Nanotube Sensors Across Multiple Spectral Wavelengths

Owing to the value of DNA-wrapped single-walled carbon nanotube (SWNT) based sensors for chemically-specific imaging in biology, we explore machine learning (ML) predictions DNA-SWNT serotonin sensor responsivity as a function of DNA sequence based on the whole SWNT fluorescence spectra. Our analysis reveals the crucial role of DNA sequence in the binding modes of DNA-SWNTs to serotonin, with a smaller influence of SWNT chirality. Regression ML models trained on existing datasets predict the change in the fluorescence emission in response to serotonin, {Delta}F/F, at over a hundred wavelengths for new DNA-SWNT conjugates, successfully identifying some high- and low-response DNA sequences. Despite successful predictions, we also show that the finite size of the training dataset leads to limitations on prediction accuracy. Nevertheless, incorporating entire spectra into ML models enhances prediction robustness and facilitates the discovery of novel DNA-SWNT sensors. Our approaches show promise for identifying new chemical systems with specific sensing response characteristics, marking a valuable advancement in DNA-based system discovery.

bioengineering↗

The AMsh glia of C. elegans modulates the duration of touch-induced escape responses

Once considered mere structural support cells in the nervous system, glia have recently been demonstrated to play pivotal roles in sensorimotor processing and to directly respond to sensory stimuli. However, their response properties and contributions to sensory-induced behaviors remain little understood. In Caenorhabditis elegans, the amphid sheath glia (AMsh) directly respond to aversive odorants and mechanical stimuli, but their precise transduction machinery and their behavioral relevance remain unclear. We investigated the role of AMsh in mechanosensation and their impact on escape behaviors in C. elegans. We found that nose touch stimuli in immobilized animals induced a slow calcium wave in AMsh, which coincided with the termination of escape reversal behaviors. Genetic ablation of AMsh resulted in prolonged reversal durations in response to nose touch, but not to harsh anterior touch, highlighting the specificity of AMshs role in distinct escape behaviors. Mechanotransduction in AMsh requires the -tubulin MEC-12 and the ion channels ITR-1 and OSM-9, indicating a unique mechanosensory pathway that is distinct from the neighboring ASH neurons. We find that GABAergic signaling mediated by the GABA-A receptor orthologs LGC-37/8 and UNC-49 play a crucial role in modulating the duration of nose touch-induced reversals. We conclude that in addition to aversive odorant detection, AMsh mediate mechanosensation, play a pivotal role in terminating escape responses to nose touch, and provide a mechanism to maintain high sensitivity to polymodal sensory stimuli. SignificancePolymodal nociceptive sensory neurons have the challenge of multitasking across sensory modalities. They must respond to dangerous stimuli of one modality, but also adapt to repeated nonthreatening stimuli without compromising sensitivity to harmful stimuli from different modalities. Here we show that a pair of glia in the nematode C. elegans modulate the duration of nose-touch induced escape responses. We identify several molecules involved in the transduction of mechanical stimuli in these cells and show that they use the signaling molecule GABA to modulate neural function. We propose a mechanism through which these glia might function to maintain this polysensory neuron responsive to dangerous stimuli across different modalities.

neuroscience↗

The timing of transcription of RpoS-dependent genes varies across multiple stresses

The alternative sigma factor RpoS regulates transcription of over 1000 genes in Escherichia coli in response to many different stresses. RpoS levels rise continuously after exposure to stress, and the consequences of changing levels of RpoS for the temporal patterns of expression of RpoS-regulated genes have not been described. We measured RpoS levels at various times during the entry to stationary phase, or in response to high osmolarity or low temperature, and found that the time required to reach maximum levels varied by several hours. We quantified the transcriptome across these stresses using RNA-seq. The number of differentially expressed genes differed among stresses, with 1379 DE genes identified in stationary phase, 633 in high osmolarity, and 302 in cold shock. To quantify the timing of gene expression, we fit sigmoid or double sigmoid models to differentially expressed genes in each stress. During the entry into stationary phase, genes whose expression rose earlier tended to be those that had been found to respond most strongly to low levels of RpoS. The timing of individual genes expression was not correlated across stresses. Taken together, our results demonstrate E. coli activates RpoS with different timing in response to different stresses, which in turn generates a unique pattern of timing of the transcription response to each stress. ImportanceBacteria adapt to changing environments by altering the transcription of their genes. Specific proteins can regulate these changes. This study explored how a single protein called RpoS controls how many genes change expression during adaptation to three stresses. We found that: 1) RpoS is responsible for activating different genes in different stresses; 2) that during a stress, the timing of gene activation depends on the what stress it is, and; 3) that how much RpoS a gene needs in order to be activated can predict when that gene will be activated during the stress of stationary phase.

microbiology↗

Topical GZ21T inhibits the growth of actinic keratoses in a UVB induced model of skin carcinogenesis

Actinic keratoses (AKs) are premalignant intraepidermal neoplasms that occur as a result of cumulative sun damage. AKs commonly relapse, and up to 16% undergo malignant transformation into cutaneous squamous cell carcinoma (cSCC). There is a need for novel therapies that reduce the quantity and surface area of AKs as well as prevent malignant transformation to cSCCs. We recently showed that GZ17-6.02, an anti-cancer agent composed of curcumin, haramine, and isovanillin, inhibited the growth of H297.T cells. The present study evaluated the efficacy of a novel topical formulation of GZ17-6.02, known as GZ21T, in a murine model of AK generated by exposing SKH1 mice to ultraviolet irradiation. Treatment of mice with topical GZ21T inhibited the growth of AKs by decreasing both lesion count (p=.028) and surface area occupied by tumor (p=.026). GZ21T also suppressed the progression of AKs to cSCC by decreasing the count (p=.047) and surface area (p=.049) of lesions more likely to represent cSCC. RNA sequencing and proteomic analyses revealed that GZ21T suppressed several pathways, including MAPK (p=.026), Pi3K-Akt (p=.028), HIF-1 (p=.030), Wnt (p=.031), insulin (p=.011), and ErbB (p=.006) signaling. GZ21T also upregulated the autophagy-promoting protein AMPK, while suppressing proteins such as PD-L1, glutaminase, pAkt1 S473, and eEF2K. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/506864v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@1254e6corg.highwire.dtl.DTLVardef@3fd190org.highwire.dtl.DTLVardef@1d75eb5org.highwire.dtl.DTLVardef@8afc97_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗