Biology subjects

Anekalla, K. R.

Publications and source records attributed to Anekalla, K. R..

4 recordsLinked to original sources

bioRxiv2020

Vimentin is Required for Tumor Progression and Metastasis in a Mouse Model of Non-Small Cell Lung Cancer

Vimentin, a type III intermediate filament, is highly expressed in aggressive epithelial cancers and is associated with increased rates of metastasis. We show that vimentin is causally required for lung cancer metastasis using a genetic mouse model of lung adenocarcinoma (LSL-KrasG12D;Tp53fl/fl, termed KPV+/+) crossed with vimentin-null mice (thereby creating KPV-/- mice). Both KPV+/+ and KPV-/- mice developed lung tumors, yet KPV-/- mice had delayed tumorigenesis and prolonged survival. KPV+/+ cells implanted in the flank metastasized to the lung while KPV-/- cells did not, providing additional evidence that vimentin is required for metastasis. Differential expression analysis of RNA-seq data demonstrated that KPV-/- cells had suppressed expression of genes that drive epithelial-to-mesenchymal transition, migration, and invasion, processes that are critical to the metastatic cascade. Integrative metabolomic and transcriptomic analysis revealed altered glutaminolysis, with KPV-/- cells accumulating glutathione, leading to impaired cell motility in response to oxidative stress. Together, these results show that loss of vimentin impairs epithelial-to-mesenchymal transition and regulation of the oxidative stress response, resulting in decreased metastasis in murine lung adenocarcinoma.

cancer biology↗

bioRxiv2020

Maintenance DNA methylation is essential for regulatory T cell development and stability of suppressive function

Regulatory T (Treg) cells require Foxp3 expression and induction of a specific DNA hypomethylation signature during development, after which Treg cells persist as a self-renewing population that regulates immune system activation. Whether maintenance DNA methylation is required for Treg cell lineage development and stability and how methylation patterns are maintained during lineage self-renewal remain unclear. Here, we demonstrate that the epigenetic regulator Uhrf1 is essential for maintenance of methyl-DNA marks that stabilize Treg cellular identity by repressing effector T cell transcriptional programs. Constitutive and induced deficiency of Uhrf1 within Foxp3+ cells resulted in global yet non-uniform loss of DNA methylation, derepression of inflammatory transcriptional programs, destabilization of the Treg cell lineage, spontaneous inflammation, and enhanced tumor immunity. These findings support a paradigm in which maintenance DNA methylation is required in distinct regions of the Treg cell genome for both lineage establishment and stability of identity and suppressive function.

immunology↗

bioRxiv2019

The Aging Microenvironment Shapes Alveolar Macrophage Identity in Aging

A dysfunctional response to inhaled pathogens and toxins drives a substantial portion of the susceptibility to acute and chronic lung disease in the elderly. We used transcriptomic profiling combined with genetic lineage tracing, heterochronic adoptive transfer, parabiosis and treatment with metformin to show that the lung microenvironment defines the phenotype of long-lived alveolar macrophages during aging. While tissue-resident alveolar macrophages persist in the lung without input from monocytes over the lifespan, severe lung injury results in their replacement with monocyte-derived alveolar macrophages. These monocyte-derived alveolar macrophages are also shaped by the microenvironment both during aging and in response to a subsequent environmental challenge to become transcriptionally and functionally similar to tissue-resident alveolar macrophages. These findings show that changes in alveolar macrophage phenotypes during injury and aging are not cell autonomous but instead are shaped by changes in the aging lung microenvironment.

immunology↗

bioRxiv2018

Single-Cell Transcriptomic Analysis of Human Lung Reveals Complex Multicellular Changes During Pulmonary Fibrosis

Pulmonary fibrosis is a devastating disorder that results in the progressive replacement of normal lung tissue with fibrotic scar. Available therapies slow disease progression, but most patients go on to die or require lung transplantation. Single-cell RNA-seq is a powerful tool that can reveal cellular identity via analysis of the transcriptome, but its ability to provide biologically or clinically meaningful insights in a disease context is largely unexplored. Accordingly, we performed single-cell RNA-seq on lung tissue obtained from eight transplant donors and eight recipients with pulmonary fibrosis and one bronchoscopic cryobiospy sample. Integrated single-cell transcriptomic analysis of donors and patients with pulmonary fibrosis identified the emergence of distinct populations of epithelial cells and macrophages that were common to all patients with lung fibrosis. Analysis of transcripts in the Wnt pathway suggested that within the same cell type, Wnt secretion and response are restricted to distinct non-overlapping cells, which was confirmed using in situ RNA hybridization. Single-cell RNA-seq revealed heterogeneity within alveolar macrophages from individual patients, which was confirmed by immunohistochemistry. These results support the feasibility of discovery-based approaches applying next generation sequencing technologies to clinically obtained samples with a goal of developing personalized therapies.\n\nOne Sentence SummarySingle-cell RNA-seq applied to tissue from diseased and donor lungs and a living patient with pulmonary fibrosis identifies cell type-specific disease-associated molecular pathways.

systems biology↗