Andreyeva et al. generated a mouse model that uncovers how immune cells destroy the adrenal glands in Addison’s disease and identified IFN-γ as a promising target for future therapies. The cover image shows characteristic granuloma formation within the adrenal cortex. Immunofluorescence staining was performed for DAPI (blue) to visualize nuclei and CYP11A1 (red) to identify steroidogenic adrenocortical cells. Granulomatous lesions appear green because of the strong intrinsic autofluorescence of lipid-laden macrophages within the granulomas. Image credit: Arina Andreyeva and Ales Neuwirth.
Resistance to endocrine therapy (ET) in ER+ breast cancer is mediated by Notch signaling, but the clinical application of anti-Notch therapy has been limited by the lack of predictive biomarkers. To identify Notch-regulated biomarkers, we conducted a pre-surgical window study evaluating ET combined with the γ-secretase inhibitor (GSI) MK-0752. RNA expressions in tumors were measured using an Affymetrix array and by real-time PCR. ET plus GSI showed more genes were decreased than ET alone. Specifically, DAXX, NOXA, and LFNG RNAs were increased, while fifteen additional transcripts were decreased. Mechanistically, GSI reduced Notch1 occupancy at CSL-binding elements within HES1, HEY2, HEYL, CCND1, MKI67, and DAXX genes, and inhibited cancer stem cells (CSCs) by 90% to 100%. This anti-CSC effect required DAXX, while GSI treatment or Notch1/4 knockdown increased DAXX expression, suggesting transcriptional repression by Notch. Using mouse tumor xenograft studies, ET plus MK-0752 resulted in complete regression of MCF-7 tumors, with DAXX-high tumors showing greater treatment sensitivity. Clinically, high DAXX expression was associated with improved recurrence-free and overall survival. This study found that anti-Notch plus ET in ER+ breast cancer inhibits cancer stem cells by increasing DAXX, a promising predictive biomarker. These findings support clinical evaluation of therapies that increase DAXX expression.
Kathy S. Albain, Debra Wyatt, Andrei Zlobin, Susan G. Hilsenbeck, Cheryl M. Czerlanis, Daniel S. Peiffer, Kyle R. Convington, Constantine Godellas, Shelly S. Lo, Patricia A. Robinson, Kathy Czaplicki, Barbara Busby, Davide Bova, Ping Tang, Patrick J. Stiff, Suzanne A.W. Fuqua, Lucio Miele, Clodia Osipo
Defective feedback inhibition of serine palmitoyltransferase (SPT) caused by pathogenic SPTSSA variants underlies childhood-onset complex hereditary spastic paraplegia, yet the developmental timing and therapeutic reversibility of sphingolipid dysregulation remain unclear. We generated a knock-in mouse carrying the disease-associated SptssaT51I variant and show that heterozygous animals exhibit preserved intrinsic SPT activity but impaired ORMDL-mediated regulation, leading to sustained elevation of bioactive sphingolipid intermediates that peak during postnatal myelination. Although gross myelin formation was initially maintained, excess sphingolipid flux rendered oligodendrocytes and neurons selectively vulnerable. Dietary L-serine, which augments SPT substrate availability, amplified sphingolipid accumulation in mutant but not wild-type mice, unmasking progressive spasticity, axonal injury, myelin ultrastructural defects, and, when administered during early postnatal development, severe pulmonary pathology likely responsible for lethality. Pharmacologic SPT inhibition with myriocin normalized sphingolipid synthesis, prevented serine-induced lethality, and reversed neurological and metabolic abnormalities. Translating these findings, treatment of a child with SPTSSA-T51I–associated complex hereditary spastic paraplegia using the FDA approved SPT inhibitor D-Cycloserine resulted in sustained improvement in spasticity, reduced baclofen requirement, and decreased plasma levels of neurofilament light chain (NFL). These data define dysregulated sphingolipid biosynthesis as a developmentally and metabolically sensitive driver of neurodegeneration and suggest SPT inhibition as a mechanistically grounded therapeutic strategy.
Yi Gong, Robert Thompson, Ashley M. Glover, Kenneth Gable, Sita D. Gupta, Natalie Golovanov, Julie Tassinari, Nathan Casey, Brian D. Wishart, Elise L. Townsend, April Qian, Martin Selig, Armen Yerevanian, Teresa M. Dunn, Florian Eichler
Premature infants often require supplemental oxygen therapy, a major risk factor for bronchopulmonary dysplasia and subsequent neurodevelopmental impairment. To determine how neonatal hyperoxia affects prefrontal cortex (PFC) development, we exposed neonatal mice to 85% oxygen (O₂) from postnatal day (P)1–P14 and performed integrated single-nucleus transcriptomic and chromatin accessibility profiling with in vivo and in vitro validation. Hyperoxia induced sex-dependent cellular remodeling, reducing L4/5 intratelencephalic projecting glutamatergic neurons in females and mature oligodendrocytes in males. Across both sexes, hyperoxia suppressed oligodendrocyte maturation, with decreased expression of the myelination genes proteolipid protein 1 (Plp1) and myelin basic protein (Mbp), altered chromatin accessibility, and increased oligodendrocyte transcription factor 2 (OLIG2) protein expression. Regulatory responses were sex specific, with tumor protein p53 (TP53)-regulated metabolic disruption and lysine demethylase 3A (Kdm3a) induction in females, and Netrin-1 signaling in males. Hyperoxia impaired oligodendrocyte progenitor cell (OPC) proliferation and differentiation. These abnormalities were recapitulated in postmortem PFC tissue from infants with BPD and human induced pluripotent stem cell (iPSC)-derived OPCs. These findings show that neonatal hyperoxia disrupts PFC development through sex-dependent effects on neuronal and oligodendrocyte lineages while converging on impaired myelination, highlighting oligodendrocyte dysfunction as a clinically relevant consequence of neonatal oxygen exposure.
Xingrao Ke, Wei Yu, Carl F. Schreck, Joseph M. Varberg, Melissa A. Gener, Daniel A. Louiselle, Sheng Xia, Sherry M. Mabry, Heather L. Menden, Venkatesh Sampath, Robert H. Lane, Kaela M. Varberg
BACKGROUND. Long-COVID, or post-acute sequelae of COVID-19 (PASC), leads to debilitating physical and cognitive deficits. No PASC molecular signature present in patients with diverse symptoms has been described. While PASC engages pathways regulating pro-fibrotic programs, no comparison of PASC with fibrosis-associated epigenetic landscapes has been reported at the bulk or single-cell level. We hypothesize that a subset of DNA methylation changes are present in PASC patients from multiple cohorts, predominate in specific immune or inflammatory cell-types, and overlap with the epigenetic profile of patients at risk of pulmonary fibrosis. METHODS. Two distinct prospective cohorts, in 2021 and in 2022-24, involving 203 patients with PASC underwent bulk whole genome methylation sequencing (WGMS). Single-cell WGMS data was generated from an independent PASC cohort. Sixty-eight pre-pandemic patients with conditions elevating risk of pulmonary fibrosis development were compared with PASC. RESULTS. Sixteen differentially methylated regions distinguished PASC versus multiple independent, healthy controls. Single-cell analysis of these regions indicated trending relative hypermethylation at multiple cell types, with T4 lymphocytes eliciting hypermethylation at most of the sequences identified to be PASC-specific DMRs in the bulk analysis. Patients at risk of pulmonary fibrosis development elicited DNA methylation changes overlapping PASC. CONCLUSION. In two independent prospective cohorts, blood WGMS identifies differentially methylated regions associated with PASC. Hypermethylation of these regions is predominantly, although not exclusively, associated with T4 lymphocytes and overlap with changes present in pre-pandemic pulmonary fibrosis at-risk patients. FUNDING. National Institutes of Health award HL160661 (AJ); and AI173035 (AJ and RSA).
Andy Madrid, Joseph Balnis, Lisa A. Drake, Anupama Tiwari, Vraj J. Patel, Paul J. Feustel, Jihua Liu, Sündüz Keleş, Fangxiu Xu, Chris L. Wright, Alvaro G. Hernandez, Recai Yucel, Marc A. Judson, Harold A. Singer, Reid S. Alisch, Ariel Jaitovich
BACKGROUND. Hepatocellular carcinoma (HCC) exhibits molecular heterogeneity that challenges histopathologic classification and biomarker discovery. We assessed whether spatially resolved N-glycan imaging with machine learning could classify tumor regions and infer glutamine synthetase (GS) status. METHODS. In this retrospective study, MALDI mass spectrometry imaging of N-glycans was performed on formalin-fixed, paraffin-embedded sections from two independent cohorts (discovery, n = 88; validation, n = 60) with pathologist annotation. An XGBoost classifier was trained on 90 discriminative N-glycan features using patient-grouped cross-validation. Performance was assessed by AUC for pixel- and biopsy-level discrimination of tumor from adjacent non-tumor tissue, and for GS status classification. RESULTS. Pixel-level AUCs were 0.95 (cross-validation) and 0.89 (external validation); biopsy-level AUCs were 1.0 and 0.97, correctly identifying 97% of tumor-containing biopsies. Probability maps recapitulated pathologist-defined boundaries; UMAP embeddings captured inter- and intratumoral heterogeneity. Discriminative species (m/z 2393.846, 1905.634, 1743.579, 1809.639) reflected complex, fucosylated, branched remodeling. N-glycans bearing six GlcNAc residues were enriched in GS+ (n = 45) versus GS− (n = 17) tumors (P = 0.001) and discriminated GS status (AUC = 0.75), consistent with GLUL and MGAT5 upregulation in TCGA-LIHC. CONCLUSION. MALDI N-glycan imaging with machine learning enables spatially resolved, objective classification of HCC and links glycan phenotypes to tumor-associated metabolic programs. TRIAL REGISTRATION. Not applicable; retrospective analysis of archival, de-identified tissue. FUNDING. NIH/NCI R01CA285370, 1R01CA289381, R33CA267226, R01CA282022, R21CA263464, R21CA286287, R01CA253460, S10OD030212, R01CA251155, R01CA250227, U01CA271887, P50CA295495, P30CA138313, P20GM130457, P30DK123704, P30DK120531,R24DK139775; NIH/NIA R01AG078702; Smart State Endowment, State of South Carolina; LeDucq Foundation.
Muhammed F. Bayram, Jade K. Macdonald, Andrew DelaCourt, Peggi M. Angel, Richard R. Drake, Aatur Singhi, David Geller, Satdarshan P. Monga, Amit Singal, Anand Mehta