Search bioRxiv⌕ Search

Biology subjects

Song, W.-M.

Publications and source records attributed to Song, W.-M..

6 recordsLinked to original sources

Single-Nuclei Transcriptomic Characterization of APOE4-Associated Alzheimer's Disease

Apolipoprotein E (APOE) genotype contributes significantly to Alzheimers disease (AD) risk and pathogenesis. Cell-type specific effects of APOE alleles have been studied. However, due to the variable prevalence of APOE genotypes within human populations, characterization of cell-type specific transcriptomes across APOE genotypes has been challenging. Here, we integrated previous and newly generated single-nuclei sequencing (snRNA-seq) data in the prefrontal cortex (PFC) from individuals across APOE genotypes (2/2, 2/3, 3/3, 3/4, 4/4). Clustering analysis revealed distinct excitatory and microglial subpopulations that were uniquely enriched or depleted for APOE4/4 AD. Notably, an excitatory neuronal cluster exhibited neurofibrillary tangle (NFT) signatures and was selectively depleted in APOE4/4 AD cases. In addition, several microglial subpopulations were influenced by both APOE4 dosage and disease status. Among these, the putative AD risk gene FRMD4A emerged as APOE4 dose and AD-dependent. These findings were validated by RNAscope in an extended cohort. Together, our findings provide insights into how APOE4 reshapes cellular states and contributes to cell-type-specific vulnerability in AD.

neuroscience↗

ZNF180 modulates tumor intrinsic immunotherapy resistance in melanoma through driving plasticity

BackgroundBased on our previous study, we have identified ZNF180, a zinc finger protein, as a pro-tumorigenic regulator in primary melanoma and a marker for poor prognosis. Herein, we report that ZNF180-regulated pathway, hence ZNF180-regulome, underlies resistance towards immune checkpoint inhibitions (ICIs). MethodsTo investigate regulatory roles of ZNF180 to confer these immune suppressive phenotypes, we performed ZNF180 knock-down in melanoma cells in vitro with different genetic backgrounds, namely A375 (BRAF-mutant) and SKMEL147 (NRAS-mutant) cells, and performed RNA- and ATAC-sequencing. We performed integrative analysis of RNA- and ATAC-sequencing data with publicly available sequencing data from ICI-treated cohorts to construct comprehensive model of ZNF180-regulome and its impacts on immune microenvironment. Further, we performed ZNF180 silencing in immune competent Yumm1.7 murine model to confirm the changes in immune microenvironments. ResultsZNF180-regulome was predictive of ICI responses in independent bulk sequencing cohorts, and ZNF180+ tumors persisted after the therapy with immune-suppressive features such as MHC-I loss and CD155 expressions, the primary ligand to TIGIT inhibitory receptor. Further, ZNF180 silencing revealed its regulations on AP-1 transcription factors to drive melanoma reprogramming towards de-differentiated MITFlowAXLhigh cells, an established melanoma subtypes associated with recurrence and ICI resistance. In tandem, we observed that ZNF180+ tumor neighborhood significantly excluded with CD4 T-cells in metastatic tumor, and its silencing in immune competent murine model increased CD4 helper T-cell infiltrations with significant tumor regression in vivo. ConclusionCollectively, these results indicate ZNF180 is a tumor intrinsic regulator of melanoma plasticity to drive de-differentiated phenotypes with immune-suppressive features including loss of immunogenicity, T-cell inhibitory signals through TIGIT/CD155 checkpoint and exclusion of CD4 helper T-cells. As ZNF180-regulome manifests in non-metastatic melanoma in contrast to the current focus of standard-of-care ICI on the metastatic disease, these results establish ZNF180-regulome as a biomarker and novel therapeutic avenue for early-stage, non-metastatic melanoma to intervene ICI resistance.

cancer biology↗

Single-Cell Network Analysis Identifies CLEC4E as a Key Mediator of Proinflammatory mDC Responses in Influenza Infection

The severity of influenza is often driven by an excessive host immune response rather than the virus itself, yet the key molecular drivers within specific immune cells remain poorly understood. While recent single-cell RNA sequencing studies have successfully identified immune populations involved, they have largely not identified the upstream drivers modulating their pro-inflammatory functions. Here we employed an integrated single-cell co-expression network to address this gap. Our analysis identified myeloid dendritic cells (mDCs) as central to pro-inflammatory response during infection. Through a multi-layered key driver analysis, we pinpointed C-type lectin, CLEC4E as a top candidate modulating this pathological inflammatory response. The role of CLEC4E was confirmed in an independent single-cell dataset from influenza-infected patients and further validated in vivo. Pharmacological inhibition of CLEC4E in a murine influenza model significantly reduced disease severity and lower viral titers in the lungs. This study not only clarifies that CLEC4E overexpression in mDCs contributes to pro-inflammatory signaling pathways influencing influenza severity but also shows the power of single-cell network approaches to uncover novel and robust therapeutic targets hidden within complex immune responses.

systems biology↗

Master regulators governing protein abundance across ten human cancer types

Protein abundance correlates only moderately with mRNA levels, and are modulated post-transcriptionally by a network of regulators including ribosomes, RNA-binding proteins (RBPs), and the proteasome. Here, we identified Master Protein abundance Regulators (MaPRs) across ten cancer types by devising a new computational pipeline that jointly analyzed transcriptomes and proteomes from 1,305 tumor samples. We identified 232 to 1,394 MaPRs per cancer type, mediating up to 79% of post- transcriptional regulatory networks. MaPRs exhibit high network connectivity, strong genetic dependency in cancer cells, and significant enrichment for RBPs. Combining tumor up-regulation, druggability, and target network analyses identified cancer-specific vulnerabilities. MaPRs predict tumor proteomic subtypes more accurately than other proteins. Finally, significant portions of RBP MaPR-target relationships were validated by experimental evidence from eCLIP binding and knockdown assays. Our findings uncover central MaPRs that govern post-transcriptional networks, highlighting diverse processes underlying human proteome regulation and identifying key regulators in cancer biology.

systems biology↗

Single-cell atlas of progressive supranuclear palsy reveals a distinct hybrid glial cell population

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder whose molecular complexity at a single cell level has not been evaluated. Here we analyzed 45,559 high quality nuclei from the subthalamic nucleus and associated basal ganglia regions from post-mortem human PSP brains with varying degrees of tau pathology compared to controls (n=3 per group). We identified novel astrocyte-oligodendrocyte hybrid cell populations that overexpress neurotropic factors in conjunction with suppression of the unfolded protein response pathway. Notably, trajectory analysis identified subpopulations of hybrid cells with distinct astrocytic, oligodendrocytic and hybrid molecular states that change from a neuroprotective hybrid cell to an astrocytic cell with impaired homeostatic function in PSP. Our single nucleus transcriptomic data provides insights into the cell-type-specific contributions to the disease for investigating the molecular and cellular basis of PSP.

neuroscience↗

Gut microbiota density influences host physiology and is shaped by host and microbial factors

To identify factors that regulate gut microbiota density and the impact of varied microbiota density on health, we assayed this fundamental ecosystem property in fecal samples across mammals, human disease, and therapeutic interventions. Physiologic features of the host (carrying capacity) and the fitness of the gut microbiota shape microbiota density. Therapeutic manipulation of microbiota density in mice altered host metabolic and immune homeostasis. In humans, gut microbiota density was reduced in Crohns disease, ulcerative colitis, and ileal pouch-anal anastomosis. The gut microbiota in recurrent Clostridium difficile infection had lower density and reduced fitness that were restored by fecal microbiota transplantation. Understanding the interplay between microbiota and disease in terms of microbiota density, host carrying capacity, and microbiota fitness provide new insights into microbiome structure and microbiome targeted therapeutics.

microbiology↗