Donor-recipient (D-R) mismatches outside of human leukocyte antigens (HLA) contribute to kidney allograft loss, but mechanisms remain unclear, specifically for intronic mismatches. We quantified non-HLA mismatches at variant-, gene-, and genome-wide scales from SNP data of D- Rs from two well-phenotyped transplant cohorts: Genomics of Chronic Allograft Rejection (GoCAR; n=385) and Clinical Trials in Organ Transplantation-01/17 (CTOT-01/17; n=146). Unbiased gene-level screening in GoCAR uncovered the LIMS1 locus as the top-ranked gene where D-R mismatches associated with death-censored graft loss (DCGL). A previously unreported, intronic, LIMS1 haplotype of 30 SNPs independently associated with DCGL in both cohorts. Haplotype mismatches showed a dosage effect, and minor-allele introduction to major- allele-carrying recipients showed greater hazard of DCGL. The LIMS1 haplotype and the previously reported LIMS1 SNP rs893403 are expression quantitative trait loci (eQTL) in immune cells for GCC2 (not LIMS1), which encodes a protein involved in mannose-6-phosphase receptor (M6PR) recycling. Peripheral blood and T-cell transcriptome analyses associated GCC2 gene and LIMS1 SNPs with the TGFB1-SMAD pathway, suggesting a regulatory effect. In vitro GCC2 modulation impacted M6PR-dependent regulation of active TGFB1 and downstream signaling in T-cells. Together, our data link LIMS1 locus D-R mismatches to DCGL via GCC2 eQTLs that modulate TGFB1-dependent effects on T-cells.
Zeguo Sun, Zhongyang Zhang, Khadija Banu, Ian W. Gibson, Robert B. Colvin, Zhengzi Yi, Weijia Zhang, Bony De Kumar, Anand Reghuvaran, John Pell, Thomas D. Manes, Arjang Djamali, Lorenzo Gallon, Philip J. O'Connell, John He, Jordan S. Pober, Peter S. Heeger, Madhav C. Menon
The discovery of frequent 8p11-p12 amplifications in squamous cell lung cancer has fueled hopes that FGFR1, located inside this amplicon, might be a therapeutic target. In a clinical trial, only 11% of patients with 8p11 amplification (detected by FISH) responded to FGFR kinase inhibitor treatment. To understand the mechanism of FGFR1 dependency, we performed deep genomic characterization of 52 squamous cell lung carcinomas with 8p11-p12-amplification, including 10 tumors obtained from patients who had been treated with FGFR inhibitors. We discovered somatically altered variants of FGFR1 with deletion of exons 1-8 that resulted from intragenic tail-to-tail rearrangements. These ectodomain-deficient FGFR1 variants (ΔEC-FGFR1) were expressed in the affected tumors and tumorigenic in in-vitro and in-vivo. Mechanistically, Breakage-Fusion-Bridges were the source of 8p11-p12 amplification, resulting from frequent head-to-head and tail-to-tail rearrangements. However, only tumors with tail-to-tail rearrangements within or in close proximity upstream of FGFR1 exhibited FGFR1 dependency. Thus, the genomic events shaping the architecture of the 8p11-p12 amplicon provide a mechanistic explanation for the emergence of FGFR1-driven squamous cell lung cancer. Specifically, FGFR1 ectodomain deficient and FGFR1-centered amplifications caused by tail-to-tail rearrangements are novel somatic genomic event, which might be predictive of therapeutically relevant FGFR1 dependency.
Florian Malchers, Lucia Nogova, Martijn H. van Attekum, Lukas Maas, Johannes Brägelmann, Christoph Bartenhagen, Luc Girard, Graziella Bosco, Ilona Dahmen, Sebastian Michels, Clare E. Weeden, Andreas H. Scheel, Lydia Meder, Kristina Golfmann, Philipp Schuldt, Janna Siemanowski, Jan Rehker, Sabine Merkelbach-Bruse, Roopika Menon, Oliver Gautschi, Johannes M. Heuckmann, Elisabeth Brambilla, Marie-Liesse Asselin-Labat, Thorsten Persigehl, John D. Minna, Henning Walczak, Roland T. Ullrich, Matthias Fischer, Hans Christian Reinhardt, Juergen Wolf, Reinhard Büttner, Martin Peifer, Julie George, Roman K. Thomas
Clonal hematopoiesis of indeterminate potential (CHIP) is associated with an increased risk of cardiovascular diseases (CVD), putatively via inflammasome activation. We pursued an inflammatory gene modifier scan for CHIP-associated CVD risk among 424,651 UK Biobank participants. CHIP was identified using whole exome sequencing data of blood DNA and modeled both as a composite and for common drivers (DNMT3A, TET2, ASXL1, and JAK2) separately. We developed predicted gene expression scores for 26 inflammasome-related genes and assessed how they modify CHIP-associated CVD risk. We identify IL1RAP as a potential key molecule for CHIP-associated CVD risk across genes and increased AIM2 gene expression leading to heightened JAK2- and ASXL1-associated CVD risks. We show that CRISPR-induced Asxl1 mutated murine macrophages have a particularly heightened inflammatory response to AIM2 agonism, associated with an increased DNA damage response, as well as increased IL-10 secretion, mirroring a CVD protective effect of IL10 expression in ASXL1 CHIP. Our study supports the role of inflammasomes in CHIP-associated CVD and provides new evidence to support gene-specific strategies to address CHIP-associated CVD risk.
Zhi Yu, Trevor P. Filder, Yunfeng Ruan, Caitlyn Vlasschaert, Tetsushi Nakao, Md Mesbah Uddin, Taralynn Mack, Abhishek Niroula, J. Brett Heimlich, Seyedeh M. Zekavat, Christopher J. Gibson, Gabriel K. Griffin, Yuxuan Wang, Gina M. Peloso, Nancy Heard-Costa, Daniel Levy, Ramachandran S. Vasan, François Aguet, Kristin G. Ardlie, Kent D. Taylor, Stephen S. Rich, Jerome I. Rotter, Peter Libby, Siddhartha Jaiswal, Benjamin L. Ebert, Alexander G. Bick, Alan R. Tall, Pradeep Natarajan
Protein aggregation is a hallmark of many neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). Although mutations in TARDBP, encoding TDP-43, account for less than 1% of all ALS cases, TDP-43-positive aggregates are present in nearly all ALS patients, including patients with sporadic ALS (sALS) or carrying other familial ALS (fALS)-causing mutations. Interestingly, TDP-43 inclusions are also present in subsets of patients with frontotemporal dementia, Alzheimer’s disease, and Parkinson’s disease; therefore, methods of activating intracellular protein quality control machinery capable of clearing toxic cytoplasmic TDP-43 species may alleviate disease-related phenotypes. Here, we identify a novel function of Nemo-like kinase (Nlk) as a negative regulator of lysosome biogenesis. Genetic or pharmacological reduction of Nlk increased lysosome formation and improved clearance of aggregated TDP-43. Furthermore, Nlk reduction ameliorated pathological, behavioral, and lifespan deficits in two distinct mouse models of TDP-43 proteinopathy. Because many toxic proteins can be cleared along the autophagy-lysosome axis, targeted reduction of Nlk represents a potential approach to therapy development for multiple neurodegenerative disorders.
Leon Tejwani, Youngseob Jung, Hiroshi Kokubu, Sowmithra Sowmithra, Luhan Ni, Changwoo Lee, Benjamin Sanders, Paul J. Lee, Yangfei Xiang, Kimberly Luttik, Armand Soriano, Jennifer Yoon, Junhyun Park, Hannah H. Ro, Hyoungseok Ju, Clara Liao, Sofia Massaro Tieze, Frank Rigo, Paymaan Jafar-Nejad, Janghoo Lim
Genetic testing is essential for patients with a suspected hereditary myopathy. More than 50% of patients clinically diagnosed with a myopathy carry a variant of unknown significance in a myopathy gene, often leaving them without a genetic diagnosis. Limb-girdle muscular dystrophy (LGMD) type R4/2E is caused by mutations in β-sarcoglycan (SGCB). Together, β-, α-, γ-, and δ-sarcoglycan form a 4-protein transmembrane complex (SGC) that localizes to the sarcolemma. Biallelic loss-of-function mutations in any subunit can lead to LGMD. To provide functional evidence for the pathogenicity of missense variants, we performed deep mutational scanning of SGCB and assessed SGC cell surface localization for all 6,340 possible amino acid changes. Variant functional scores were bimodally distributed and perfectly predicted pathogenicity of known variants. Variants with less severe functional scores more often appeared in patients with slower disease progression, implying a relationship between variant function and disease severity. Amino acid positions intolerant to variation mapped to points of predicted SGC interactions, validated in silico structural models, and enabled accurate prediction of pathogenic variants in other SGC genes. These results will be useful for clinical interpretation of SGCB variants and improving diagnosis of LGMD; we hope they enable wider use of potentially life-saving gene therapy.
Chengcheng Li, Jackson Wilborn, Sara Pittman, Jil Daw, Jorge Alonso-Pérez, Jordi Díaz-Manera, Conrad C. Weihl, Gabe Haller
Epigenetic status-altering mutations in chromatin-modifying enzymes are a feature of human diseases including many cancers. However, the functional outcomes and cellular dependencies arising from these mutations remain unresolved. In this study, we investigated cellular dependencies, or vulnerabilities, that arise when enhancer function is compromised by loss of the frequently mutated COMPASS family members MLL3 and MLL4. CRISPR dropout screens in MLL3/4-depleted mouse embryonic stem cells (mESCs) revealed synthetic lethality upon suppression of purine and pyrimidine nucleotide synthesis pathways. Consistently, we observed a shift in metabolic activity towards increased purine synthesis in MLL3/4 knockout (KO) mESCs. These cells also exhibited enhanced sensitivity to the purine synthesis inhibitor lometrexol, which induced a unique gene expression signature. RNA sequencing identified the top MLL3/4 target genes coinciding with suppression of purine metabolism, and tandem mass tag (TMT) proteomic profiling further confirmed upregulation of purine synthesis in MLL3/4 KO cells. Mechanistically, compensation by MLL1/COMPASS underlied these effects. Finally, we demonstrated that tumors with MLL3 and/or MLL4 mutations were highly sensitive to lometrexol in vivo, both in culture and in animal models of cancer. Our results depicted a targetable metabolic dependency arising from epigenetic factor deficiency, providing molecular insight to inform therapy for cancers with epigenetic alterations secondary to MLL3/4 COMPASS dysfunction.
Zibo Zhao, Kaixiang Cao, Jun Watanabe, Cassandra N. Philips, Jacob M. Zeidner, Yukitomo Ishi, Qixuan Wang, Sarah R. Gold, Katherine Junkins, Elizabeth T. Bartom, Feng Yue, Navdeep S. Chandel, Rintaro Hashizume, Issam Ben-Sahra, Ali Shilatifard
Increased levels and diversity of human endogenous retrovirus (HERV) transcription characterizes most cancer types, linked with disease outcomes. However, the underlying processes are incompletely understood. We show that elevated transcription of HERVH proviruses predicts survival of lung squamous cell carcinoma (LUSC) and identify an isoform of CALB1, encoding Calbindin, ectopically driven by an upstream HERVH provirus under the control of KLF5, as the mediator of this effect. HERVH-CALB1 expression initiates in pre-invasive lesions and associates with their progression. Calbindin loss in LUSC cell lines impairs in vitro and in vivo growth and triggers senescence, consistent with a pro-tumor effect. However, Calbindin also directly controls the senescence-associated secretory phenotype (SASP), marked by secretion of CXCL8 and other neutrophil chemoattractants. In established carcinomas, CALB1-negative cancer cells become the dominant source of CXCL8, correlating with neutrophil infiltration and worse prognosis. Thus, HERVH-CALB1 expression in LUSC may display antagonistic pleiotropy, whereby the benefits of escaping senescence early during cancer initiation and clonal competition are offset by the prevention of SASP and pro-tumor inflammation at later stages.
Jan Attig, Judith Pape, Laura Doglio, Anastasiya Kazachenka, Eleonora Ottina, George R. Young, Katey S.S. Enfield, Iker Valle Aramburu, Kevin W. Ng, Nikhil Faulkner, William Bolland, Venizelos Papayannopoulos, Charles Swanton, George Kassiotis
Childhood neuroblastomas exhibit plasticity between an undifferentiated neural crest–like mesenchymal cell state and a more differentiated sympathetic adrenergic cell state. These cell states are governed by autoregulatory transcriptional loops called core regulatory circuitries (CRCs), which drive the early development of sympathetic neuronal progenitors from migratory neural crest cells during embryogenesis. The adrenergic cell identity of neuroblastoma requires LMO1 as a transcriptional cofactor. Both LMO1 expression levels and the risk of developing neuroblastoma in children are associated with a single nucleotide polymorphism, G/T, that affects a GATA motif in the first intron of LMO1. Here, we showed that WT zebrafish with the GATA genotype developed adrenergic neuroblastoma, while knock-in of the protective TATA allele at this locus reduced the penetrance of MYCN-driven tumors, which were restricted to the mesenchymal cell state. Whole genome sequencing of childhood neuroblastomas demonstrated that TATA/TATA tumors also exhibited a mesenchymal cell state and were low risk at diagnosis. Thus, conversion of the regulatory GATA to a TATA allele in the first intron of LMO1 reduced the neuroblastoma-initiation rate by preventing formation of the adrenergic cell state. This mechanism was conserved over 400 million years of evolution, separating zebrafish and humans.
Nina Weichert-Leahey, Hui Shi, Ting Tao, Derek A. Oldridge, Adam D. Durbin, Brian J. Abraham, Mark W. Zimmerman, Shizhen Zhu, Andrew C. Wood, Deepak Reyon, J. Keith Joung, Richard A. Young, Sharon J. Diskin, John M. Maris, A. Thomas Look
Neonatal herpes simplex virus (HSV) infection is a devastating disease with substantial morbidity and mortality. The genetic basis of susceptibility to HSV in neonates remains undefined. We investigated a male infant with neonatal skin/eye/mouth (SEM) HSV1 disease who had complete recovery after acyclovir but developed HSV1 encephalitis at 1 year of age. Immune work up showed an anergic peripheral blood monocyte cytokine (PBMC) response to TLR3 stimulation but no other TLRs. Exome sequencing identified rare missense variants in IRF7 and UNC93B1. PBMC single cell RNA sequencing done during childhood revealed decreased expression of several innate immune genes and a repressed TLR3 pathway signature at baseline in several immune cell populations, including CD14 monocytes. Functional studies in fibroblasts and THP-1 showed that both variants individually suppressed TLR3-driven IRF3 promoter activity and type I interferon response in vitro. Furthermore, fibroblasts expressing the IRF7 and UNC93B1 variants had higher intracellular viral titers with blunting of the type I interferon response upon HSV1 challenge. This study reports an infant with recurrent HSV1 disease complicated by encephalitis associated with deleterious variants in IRF7 and UNC93B1 genes. Our results suggest that TLR3 pathway mutations may predispose neonates to recurrent severe HSV.
Megan H. Tucker, Wei Yu, Heather L. Menden, Sheng Xia, Carl F. Schreck, Margaret I. Gibson, Daniel A. Louiselle, Tomi Pastinen, Nikita Raje, Venkatesh Sampath
The deadliest anaplastic thyroid cancer (ATC) often transforms from indolent differentiated thyroid cancer (DTC); however, the complex intra-tumor transformation process is poorly understood. We investigated an anaplastic transformation model by dissecting both cell lineage and cell fate transitions using single cell transcriptomes and genetic alteration data from patients with different subtypes of thyroid cancer. The resulting spectrum of ATC transformation included stress-responsive DTC cells, inflammatory ATC cells (iATCs), mitotic-defective ATC cells and extended all the way to mesenchymal ATC cells (mATCs). Further, our analysis identified two important milestones: 1) a diploid stage, where iATC cells were diploids with inflammatory phenotypes, and 2) an aneuploid stage, where mATCs gained aneuploid genomes and mesenchymal phenotypes producing excessive collagens and collagen-interacting receptors. In parallel, cancer-associated-fibroblasts showed strong interactions among mesenchymal cell-types, macrophages shifted from M1 to M2 states, and T cells reprogrammed from cytotoxic to exhausted states, highlighting new therapeutic opportunities for ATC.
Lina Lu, Jennifer Rui Wang, Ying C. Henderson, Shanshan Bai, Jie Yang, Min Hu, Cheng-Kai Shiau, Timothy Y. Pan, Yuanqing Yan, Tuan M. Tran, Jianzhuo Li, Rachel Kieser, Xiao Zhao, Jiping Wang, Roza Nurieva, Michelle D. Williams, Maria E. Cabanillas, Ramona Dadu, Naifa Busaidy, Mark Zafereo, Nicholas Navin, Stephen Y. Lai, Ruli Gao