👤 Elizabeth Flaherty

Obesity and Alzheimer’s disease (AD) are epidemiologically associated. The locus coeruleus (LC)—the brain’s primary and most significant source of norepinephrine—is one of the earliest sites of neurodegeneration in AD. The LC participates in feeding behavior through connections with the hypothalamus. The cellular composition of the LC has been characterized at single-cell resolution. However, the constituent cellular signatures of genes related to energy homeostasis—such as the melanocortin pathway genes—in the LC are unclear. We performed single-nucleus RNA sequencing and spatial transcriptomics (Visium) in the human LC, and HiPlex RNAscope in the LC of mice. The melanocortin pathway gene The online version contains supplementary material available at 10.1186/s40478-026-02287-x. Show less

Genetic studies have established angiopoietin-related protein 4 (ANGPTL4) as a key regulator of triglyceride metabolism and a promising target to reduce atherosclerotic cardiovascular disease (ASCVD) risk beyond traditional risk factors. Human ANGPTL4 loss-of-function shows no adverse consequences and is associated with reduced triglycerides and remnant cholesterol, and a reduced risk of type 2 diabetes and ASCVD. Nonetheless, development of ANGPTL4 inhibitors has been delayed due to adverse findings in ANGPTL4-knockout mice fed a high saturated fat diet, including lipid accumulation in mesenteric lymph nodes, systemic inflammation, adverse clinical signs, and reduced survival. We previously reported the development and preclinical characterisation of MAR001, an ANGPTL4 inhibitory antibody. Here, we report a comprehensive safety assessment of ANGPTL4 inhibition, including novel analysis of genetic ANGPTL4 loss on mesenteric lymph node architecture in humans and two early-phase clinical trials. MAR001 was evaluated in a first-in-human, randomised, placebo-controlled, single-ascending-dose phase 1 study with three parts in which participants received a single subcutaneous injection of MAR001 or placebo. The study was developed and conducted by Novartis Biomedical Research (Cambridge, MA, USA). Eligible participants enrolled in part 1A were healthy men and women aged between 18 years and 65 years with a bodyweight of at least 50 kg and a BMI of 18-30 kg/m We found no evidence of clinical adversity in human germline ANGPTL4 loss-of-function, adding to preclinical support for initiating human studies. Between Nov 20, 2017, and Sept 10, 2019, in the first-in-human, randomised, placebo-controlled, single-ascending-dose phase 1 study, part 1A enrolled 32 healthy participants: six each received 15 mg, 50 mg, 150 mg, or 450 mg of MAR001, and eight received placebo. Part 1B enrolled 12 participants: nine received 450 mg of MAR001 and three received placebo. Part 1C enrolled 12 participants: eight received 450 mg of MAR001 and four received placebo. Between Nov 24, 2013, and July 1, 2024, in the multidose phase 1b/2a randomised, double-blind, placebo-controlled study, 55 participants were randomly assigned to receive subcutaneous injections of placebo (19 participants) or MAR001 at doses of 150 mg (ten participants), 300 mg (nine participants), or 450 mg (17 participants), followed by a 12-week safety follow-up period. MAR001 was safe and generally well tolerated, and we observed no treatment-related systemic inflammatory biomarker elevations or changes in mesenteric lymph node size or inflammation assessed by MRI. MAR001 (450 mg) yielded placebo-adjusted week 12 mean reductions in triglycerides of 52·7% (90% CI -77·0 to -28·3) and in remnant cholesterol of 52·5% (-76·1 to -28·9). ANGPTL4 inhibition with MAR001 can safely and effectively reduce circulating triglycerides and remnant cholesterol. The findings of these trials support further research and development of MAR001 as a promising potential lipid-lowering therapy to reduce risk of ASCVD. Marea Therapeutics. Show less

Angiopoietin-like protein 4 (ANGPTL4) inhibition is a promising approach to manage atherogenic dyslipidaemia and residual atherosclerotic cardiovascular disease (ASCVD) risk. Human ANGPTL4 loss-of-function (LoF) is associated with reduced plasma triglyceride (TG), remnant cholesterol (RC), and apolipoprotein B (ApoB) levels, and lower risk of type 2 diabetes and ASCVD, without observable safety concerns. However, development of ANGPTL4 inhibitors has been stalled by adverse findings in Angptl4 knockout mice fed a high-saturated-fat diet (HSFD), which show lipid accumulation in mesenteric lymph nodes (MLNs), systemic inflammation, severe adverse clinical signs, and reduced survival. Here, we present the development and preclinical characterisation of MAR001, a humanised monoclonal ANGPTL4 inhibitor antibody. We assessed single-dose MAR001 efficacy in hypertriglyceridemic (HTG) non-human primates (NHPs, n = 4), and safety in two NHP toxicology studies: a 15-week subchronic study with a standard or HSFD (n = 36), and a 9-month chronic study exclusively on an HSFD (n = 24). In HTG monkeys, single-dose MAR001 treatment reduced plasma TG by up to 58%, non-high-density lipoprotein cholesterol by 38%, ApoB by 30%, and RC by 59%. In safety studies, MAR001 was well tolerated without clinically adverse findings with either diet. Animals fed an HSFD exhibited minimal to moderate foamy macrophage formation in MLNs, but importantly, these histological findings did not progress to degeneration, necrosis, inflammation, fibrosis, or other reactive changes, and with no evidence of systemic effects, including no evidence of systemic inflammation or clinical adverse signs. MAR001 improved plasma lipid profiles in NHPs without clinical adversity, even during prolonged HSFD feeding. The favourable NHP safety profile aligns with human ANGPTL4 LoF findings, and contrasts with the severe pathology in mouse knockout models on an HSFD. These findings supported MAR001 clinical studies reported in our concurrent publication, which demonstrated robust lipid improvements without lymphatic pathology. Overall, these findings support continued development of MAR001 as a promising new therapy for ASCVD risk reduction. Marea Therapeutics. Show less

This multicenter phase II basket trial investigated the efficacy, safety, and pharmacokinetics of Debio 1347, an investigational, oral, highly selective, ATP-competitive, small molecule inhibitor of FGFR1-3, in patients with solid tumors harboring a functional FGFR1-3 fusion. Eligible adults had a previously treated locally advanced (unresectable) or metastatic biliary tract (cohort 1), urothelial (cohort 2), or another histologic cancer type (cohort 3). Debio 1347 was administered at 80 mg once daily, continuously, in 28-day cycles. The primary endpoint was the objective response rate. Secondary endpoints included duration of response, progression-free survival, overall survival, pharmacokinetics, and incidence of adverse events. Between March 22, 2019, and January 8, 2020, 63 patients were enrolled and treated, 30 in cohort 1, 4 in cohort 2, and 29 in cohort 3. An unplanned preliminary statistical review showed that the efficacy of Debio 1347 was lower than predicted, and the trial was terminated. In total, 3 of 58 evaluable patients had partial responses, representing an objective response rate of 5%, with a further 26 (45%) having stable disease (≥6 weeks duration). Grade ≥3 treatment-related adverse events occurred in 22 (35%) of 63 patients, with the most common being hyperphosphatemia (13%) and stomatitis (5%). Two patients (3%) discontinued treatment due to adverse events. Debio 1347 had manageable toxicity; however, the efficacy in patients with tumors harboring FGFR fusions did not support further clinical evaluation in this setting. Our transcriptomic-based analysis characterized in detail the incidence and nature of FGFR fusions across solid tumors. See related commentary by Hage Chehade et al., p. 4549. Show less

Despite fibroblast growth factor receptor ( EAY131-K1 was an open-label, single-arm, phase II study with central confirmation of presence of Thirty-five patients were enrolled into this study with 18 included in the prespecified primary efficacy analysis. The median age of the 18 patients was 60 years, and 78% had received ≥3 previous lines of therapy. There were no confirmed responses to erdafitinib; however, five patients experienced stable disease (SD) as best response. One patient with an Erdafitinib did not meet its primary end point of efficacy as determined by ORR in treatment-refractory solid tumors harboring Show less

Subprotocol K2 (EAY131-K2) of the NCI-MATCH platform trial was an open-label, single-arm, phase II study designed to evaluate the antitumor efficacy of the oral FGFR1-4 inhibitor, erdafitinib, in patients with tumors harboring FGFR1-4 mutations or fusions. Central confirmation of tumor FGFR1-4 mutations or fusions was required for outcome analysis. Patients with urothelial carcinoma were excluded. Enrolled subjects received oral erdafitinib at a starting dose of 8 mg daily continuously until intolerable toxicity or disease progression. The primary end point was objective response rate (ORR) with key secondary end points of safety, progression-free survival (PFS), and overall survival (OS). Thirty-five patients were enrolled, and 25 patients were included in the primary efficacy analysis as prespecified in the protocol. The median age was 61 years, and 52% of subjects had received ≥3 previous lines of therapy. The confirmed ORR was 16% (4 of 25 [90% CI, 5.7 to 33.0], This study met its primary end point in patients with several pretreated solid tumor types harboring FGFR1-3 mutations or fusions. These findings support advancement of erdafitinib for patients with fibroblast growth factor receptor-altered tumors outside of currently approved indications in a potentially tumor-agnostic manner. Show less

Introduction: Despite significant advances in pediatric burn care, bloodstream infections (BSIs) remain a compelling challenge during recovery. A personalized medicine approach for accurate prediction of BSIs before they occur would contribute to prevention efforts and improve patient outcomes. Methods: We analyzed the blood transcriptome of severely burned (total burn surface area [TBSA] ≥20%) patients in the multicenter Inflammation and Host Response to Injury ("Glue Grant") cohort. Our study included 82 pediatric (aged <16 years) patients, with blood samples at least 3 days before the observed BSI episode. We applied the least absolute shrinkage and selection operator (LASSO) machine-learning algorithm to select a panel of biomarkers predictive of BSI outcome. Results: We developed a panel of 10 probe sets corresponding to six annotated genes ( ARG2 [ arginase 2 ], CPT1A [ carnitine palmitoyltransferase 1A ], FYB [ FYN binding protein ], ITCH [ itchy E3 ubiquitin protein ligase ], MACF1 [ microtubule actin crosslinking factor 1 ], and SSH2 [ slingshot protein phosphatase 2 ]), two uncharacterized ( LOC101928635 , LOC101929599 ), and two unannotated regions. Our multibiomarker panel model yielded highly accurate prediction (area under the receiver operating characteristic curve, 0.938; 95% confidence interval [CI], 0.881-0.981) compared with models with TBSA (0.708; 95% CI, 0.588-0.824) or TBSA and inhalation injury status (0.792; 95% CI, 0.676-0.892). A model combining the multibiomarker panel with TBSA and inhalation injury status further improved prediction (0.978; 95% CI, 0.941-1.000). Conclusions: The multibiomarker panel model yielded a highly accurate prediction of BSIs before their onset. Knowing patients' risk profile early will guide clinicians to take rapid preventive measures for limiting infections, promote antibiotic stewardship that may aid in alleviating the current antibiotic resistance crisis, shorten hospital length of stay and burden on health care resources, reduce health care costs, and significantly improve patients' outcomes. In addition, the biomarkers' identity and molecular functions may contribute to developing novel preventive interventions. Show less

Resource acquisition and allocation impacts individual fitness. Using pellet analysis of breeding adults and stable isotopes of carbon and nitrogen of down feathers of Kelp Gull (Larus dominicanus) nestlings, we evaluated the relationship between urban refuse (beef and chicken) and natural food (fish) consumption of individual females during the pre-incubation period, with fecundity and young nesting's success in the Río de la Plata Estuary in Uruguay. Assimilated urban refuse positively correlated with egg weight and negatively with young nestling's success. This suggests a possible impact of urban refuse foraged by females during the pre-incubation period on their immediate fecundity (positively) and young nestling's survival (negatively). Differences between studies at the individual and colony levels are also discussed in light of an "ecological fallacy" of interpretation and we thus argue for the need of additional research to evaluate this relationship further, considering potential confounding factors. Show less

Triple-negative breast cancer (TNBC) presents a clinical challenge due to the aggressive nature of the disease and a lack of targeted therapies. Constitutive activation of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway has been linked to chemoresistance and metastatic progression through distinct mechanisms, including activation of epithelial-to-mesenchymal transition (EMT) when cells adopt a motile and invasive phenotype through loss of epithelial markers (CDH1), and acquisition of mesenchymal markers (VIM, CDH2). Although MAPK/ERK1/2 kinase inhibitors (MEKi) are useful antitumor agents in a clinical setting, including the Food and Drug Administration (FDA)-approved MEK1,2 dual inhibitors cobimetinib and trametinib, there are limitations to their clinical utility, primarily adaptation of the BRAF pathway and ocular toxicities. The MEK5 (HGNC: MAP2K5) pathway has important roles in metastatic progression of various cancer types, including those of the prostate, colon, bone and breast, and elevated levels of ERK5 expression in breast carcinomas are linked to a worse prognoses in TNBC patients. The purpose of this study is to explore MEK5 regulation of the EMT axis and to evaluate a novel pan-MEK inhibitor on clinically aggressive TNBC cells. Our results show a distinction between the MEK1/2 and MEK5 cascades in maintenance of the mesenchymal phenotype, suggesting that the MEK5 pathway may be necessary and sufficient in EMT regulation while MEK1/2 signaling further sustains the mesenchymal state of TNBC cells. Furthermore, additive effects on MET induction are evident through the inhibition of both MEK1/2 and MEK5. Taken together, these data demonstrate the need for a better understanding of the individual roles of MEK1/2 and MEK5 signaling in breast cancer and provide a rationale for the combined targeting of these pathways to circumvent compensatory signaling and subsequent therapeutic resistance. Show less

Triple-negative breast cancers (TNBCs) represent 15% to 20% of all breast cancers and are often associated with poor prognosis. The lack of targeted therapies for TNBCs contributes to higher mortality rates. Aberrations in the phosphoinositide-3-kinase (PI3K) and mitogen-activated protein kinase pathways have been linked to increased breast cancer proliferation and survival. It has been proposed that these survival characteristics are enhanced through compensatory signaling and crosstalk mechanisms. While the crosstalk between PI3K and extracellular signal-regulated kinase 1/2 (ERK1/2) pathways has been characterized in several systems, new evidence suggests that MEK5/ERK5 signaling is a key component in the proliferation and survival of several aggressive cancers. In this study, we examined the effects of dual inhibition of PI3K/protein kinase B (Akt) and MEK5/ERK5 in the MDA-MB-231, BT-549, and MDA-MB-468 TNBC cell lines. We used the Akt inhibitor ipatasertib, ERK5 inhibitors XMD8-92 and AX15836, and the novel MEK5 inhibitor SC-1-181 to investigate the effects of dual inhibition. Our results indicated that dual inhibition of PI3K/Akt and MEK5/ERK5 signaling was more effective at reducing the proliferation and survival of TNBCs than single inhibition of either pathway alone. In particular, a loss of Bad phosphorylation at two distinct sites was observed with dual inhibition. Furthermore, the inhibition of both pathways led to p21 restoration, decreased cell proliferation, and induced apoptosis. In addition, the dual inhibition strategy was determined to be synergistic in MDA-MB-231 and BT-549 cells and was relatively nontoxic in the nonneoplastic MCF-10 cell line. In summary, the results from this study provide a unique prospective into the utility of a novel dual inhibition strategy for targeting TNBCs. Show less

Congenital heart defects are the most common birth defects worldwide. Although defective Notch signaling is the major cause of mouse embryonic death from cardiovascular defects, how Notch signaling is regulated during embryonic vasculogenesis and heart development is poorly understood. Regulator of G protein signaling 6 (RGS6) RGS6 and oxidized CaMKIIδ together function as novel critical upstream modulators of Notch signaling required for normal cardiovascular development and embryo survival. Their combined need indicates that they function in parallel pathways needed for Notch1 signaling in yolk sac, placenta and embryos. Thus, dysregulated embryonic RGS6 expression and oxidative activation of CaMKII may potentially contribute to congenital heart defects. Show less

Mitogen-activated protein kinases (MAPKs) regulate diverse cellular processes including proliferation, cell survival, differentiation, and apoptosis. While conventional MAPK constituents have well-defined roles in oncogenesis, the MEK5 pathway has only recently emerged in cancer research. In this review, we consider the MEK5 signaling cascade, focusing specifically on its involvement in drug resistance and regulation of aggressive cancer phenotypes. Moreover, we explore the role of MEK5/ERK5 in tumorigenesis and metastatic progression, discussing the discrepancies in preclinical studies and assessing its viability as a therapeutic target for anti-cancer agents. Show less

The protein kinase B-Raf proto-oncogene, serine/threonine kinase (BRAF) is an oncogenic driver and therapeutic target in melanoma. Inhibitors of BRAF (BRAFi) have shown high response rates and extended survival in patients with melanoma who bear tumors that express mutations encoding BRAF proteins mutant at Val600, but a vast majority of these patients develop drug resistance. Here we show that loss of stromal antigen 2 (STAG2) or STAG3, which encode subunits of the cohesin complex, in melanoma cells results in resistance to BRAFi. We identified loss-of-function mutations in STAG2, as well as decreased expression of STAG2 or STAG3 proteins in several tumor samples from patients with acquired resistance to BRAFi and in BRAFi-resistant melanoma cell lines. Knockdown of STAG2 or STAG3 expression decreased sensitivity of BRAF(Val600Glu)-mutant melanoma cells and xenograft tumors to BRAFi. Loss of STAG2 inhibited CCCTC-binding-factor-mediated expression of dual specificity phosphatase 6 (DUSP6), leading to reactivation of mitogen-activated protein kinase (MAPK) signaling (via the MAPKs ERK1 and ERK2; hereafter referred to as ERK). Our studies unveil a previously unknown genetic mechanism of BRAFi resistance and provide new insights into the tumor suppressor function of STAG2 and STAG3. Show less

Gene expression during oocyte maturation, fertilization, and early embryo development until zygotic gene activation is regulated mainly by translational activation of maternally derived mRNAs. This process requires the presence of a poly(A)-binding protein. However, the cytoplasmic somatic cell poly(A)-binding protein (PABP1) is not expressed until later in embryogenesis. We recently identified an embryonic poly(A)-binding protein (ePAB) in Xenopus. ePAB is the predominant cytoplasmic PABP in Xenopus oocytes and early embryos and prevents deadenylation of mRNAs, suggesting its importance in the regulation of gene expression during early Xenopus development. Here we report the identification of the mouse ortholog of Xenopus ePAB. The mouse ePAB gene on chromosome 2 contains 14 exons that specify an alternatively spliced mRNA encoding a protein of 608 or 561 aa with approximately 65% identity to Xenopus ePAB. Mouse ePAB mRNA is expressed in ovaries and testis but not in somatic tissues. In situ hybridization localizes ePAB RNA to oocytes and confirms its absence from surrounding somatic cells in the mouse ovary. During early development, mouse ePAB is expressed in prophase I and metaphase II oocytes and one-cell and two-cell embryos and then becomes undetectable in four-or-more-cell embryos. In contrast, PABP1 mRNA expression is minimal in oocytes and early embryos until the eight-cell stage when it increases, becoming predominant at the blastocyst stage. The expression of mouse ePAB before zygotic gene activation argues for its importance in translational activation of maternally derived mRNAs during mammalian oocyte and early preimplantation embryo development. Show less