Biology subjects

Garcia-Milian, R.

Publications and source records attributed to Garcia-Milian, R..

13 recordsLinked to original sources

bioRxiv2026

EnrichViz: An Interactive R Shiny Application for Visualization of Pathway Enrichment Results from Omics Data

Pathway and functional enrichment analysis is a cornerstone of omics data interpretation, enabling researchers to map differentially expressed proteins or genes onto curated biological processes, signaling cascades, and molecular functions. While tools such as Ingenuity Pathway Analysis (IPA), g:Profiler, and Enrichr are widely used to generate ranked enrichment results, translating these tabular outputs into clear, publication-ready figures remains a time-consuming step that typically requires custom scripting and familiarity with visualization libraries -- a significant barrier for researchers without a computational background. Here we present EnrichViz, a self-contained, browser-based R Shiny application that enables interactive, code-free visualization of pathway and functional enrichment results from quantitative proteomics, transcriptomics, and metabolomics experiments. EnrichViz accepts three standard CSV files as input -- a normalized abundance matrix, a sample annotation or metadata file, and enrichment results from any platform that exports tabular output -- and produces six complementary, publication-ready visualizations: bar and bubble plots for ranking enriched terms by significance, chord diagrams for exploring pathway-molecule connectivity, clustered heatmaps for displaying Z-score normalized expression patterns across experimental groups, and boxplots or violin plots for examining the abundance distribution of individual proteins, genes, or metabolites. The application supports both raw p-values and pre-transformed -log10(p) values through automatic detection, and all plot parameters are adjustable in real time through a graphical sidebar. Every figure can be exported as a high-resolution PNG file at 300 dpi. EnrichViz is implemented in R using the Shiny, ggplot2, pheatmap, and circlize packages, and is freely available at https://rgmilian.shinyapps.io/EnrichViz/.

bioinformatics↗

bioRxiv2026

mPFC Synaptosome Proteomics Reveals Novel Pathways and Muscarinic Receptor Changes in a Learned Helplessness Mouse Model

Stressful events are a leading factor in development of depression. The medial prefrontal cortex (mPFC) is strongly associated with depression etiology and exposure to uncontrollable stressors results in synaptic dysfunction and loss. Learned helplessness is a behavioral paradigm that measures effects of repeated exposure to uncontrollable, inescapable stress on later responses to escapable stress. We therefore performed a proteomic analysis of mPFC synaptosomes in a mouse learned helplessness model to identify molecular changes that could contribute to functional consequences of inescapable stress. Male and female mice were evaluated at baseline and following exposure to escapable or inescapable stress followed by an active avoidance test. Label-free mass spectrometry followed by pathway and protein-protein interaction network analyses identified alterations in signaling pathways involved in energy metabolism, neurotransmitter signaling, and protein shuttling. Furthermore, phosphoproteomics revealed alterations related to synaptic function, neurotransmitter signaling and protein internalization, as well as changes in activity of kinases previously identified as mediators of antidepressant efficacy (GSK3B) and receptor internalization (ADRBK1). We more deeply examined alterations in the Acetylcholine Receptor Signaling Pathway, and identified muscarinic receptor proteins (Chrm1, Chrm2, Chrm4) and key proteins involved in their translocation to and from the membrane. These results identify substantial changes in the mPFC proteome following exposure to inescapable stressors. In addition, mPFC muscarinic cholinergic signaling is well placed to mediate responses to an inescapable stressor. This proteomic study will be useful in guiding studies of human mPFC relevant to depression. Data are available via ProteomeXchange with identifier PXD073765.

neuroscience↗

bioRxiv2025

ATG2A engages Rab1a and ARFGAP1 positive membranes during autophagosome biogenesis

Autophagosomes form from seed membranes that expand through bulk-lipid transport via the bridge-like lipid transporter ATG2. The origins of the seed membranes and their relationship to the lipid transport machinery are poorly understood. Using proximity labeling and a variety of fluorescence microscopy techniques, we show that ATG2A localizes to extra-Golgi ARFGAP1 puncta during autophagosome biogenesis. ARFGAP1 itself is dispensable during macroautophagy, but among other proteins associating to these membranes, we find that RAB1 is essential. ATG2A co-immunoprecipitates strongly, albeit indirectly, with RAB1A, and siRNA-mediated depletion of RAB1A/B blocks autophagy downstream of LC3B lipidation, similar to ATG2A depletion. Further, when either autophagosome formation or the early secretory pathway is perturbed, ARFGAP1 and RAB1A accumulate at ectopic locations with autophagic machinery. Our results indicate that ATG2A engages a RAB1A complex on select early secretory membranes in support of autophagosome biogenesis. Significance StatementThis study expounds upon the role of early secretory membranes in autophagosome biogenesis. The authors demonstrate that RAB1/ARFGAP1-positive membranes are essential to autophagy and are recruited to the phagophore assembly site at an early step of autophagosome biogenesis. These membranes interact with the bridge-like lipid transport protein ATG2A and are positive for LC3B and WIPI2, suggesting that RAB1 membranes are a direct source for autophagosome formation.

cell biology↗

bioRxiv2025

SPINK1-COL18A1 Crosstalk Shapes Epigenome and Drives Cancer Stemness in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a devastating cancer with an increasing incidence and extremely dismal prognosis. Discovery and mechanistic understanding of the genetic and epigenetic drivers of PDAC is therefore of critical importance. Here, we uncover serine protease inhibitor Kazal type 1 (SPINK1) as a putative determinant of clinical progression and demonstrate that it can have a non-canonical function as a regulator of epigenomic states of PDAC cells and associated extensive changes in gene expression. We show that SPINK1 expression, which varies in PDAC, is associated with key aggressive phenotypic cancer states and is correlated with the expression of stemness markers both in vitro and in patient samples. Mechanistically, our results strongly suggest that SPINK1 acts through a new signaling axis, by interacting with COL18A1 in the Golgi apparatus, promoting endostatin release and eventually inducing extensive histone H3 modifications. These results reveal a new function of SPINK1 in PDAC and suggest a potential therapeutic route to combat PDAC aggressiveness by targeting the SPINK1-COL18A1-endostatin signaling.

cancer biology↗

bioRxiv2025

Liver Lymphatic Dysfunction as a Driver of Fibrosis and Cirrhosis Progression

The liver lymphatic system plays a critical role in maintaining interstitial fluid balance and immune regulation. Efficient lymphatic drainage is essential for liver homeostasis, but its role in liver disease progression remains poorly understood. In cirrhosis, lymphangiogenesis initially compensates for increased lymph production, but impaired lymphatic drainage in advanced stages may lead to complications such as ascites and portal hypertension. This study aimed to evaluate how liver lymphatic dysfunction affects disease progression and to assess therapeutic strategies. Using a surgical model to block liver lymphatic outflow, we found that impaired drainage accelerates liver injury, fibrosis, and immune cell infiltration, even in healthy livers. Mechanistically, enhanced TGF-{beta} signaling in liver lymphatic endothelial cells (LyECs) contributed to reduced lymphatic vessel (LV) density and function in late-stage decompensated cirrhosis. This dysfunction was linked to the progression from compensated to decompensated cirrhosis, particularly in patients with primary sclerosing cholangitis (PSC). Conversely, liver-specific overexpression of VEGF-C via AAV8 improved lymphatic drainage, restored LV density, reduced fibrosis, mitigated liver injury, and alleviated portal hypertension in cirrhotic rats. These findings establish impaired liver lymphatic function as a pivotal driver of cirrhosis progression and identify VEGF-C as a promising therapeutic target to prevent decompensation.

pathology↗

bioRxiv2024

Proliferative arrest induces neuron differentiation and innate immune responses in control and Creutzfeldt-Jakob Disease agent infected rat septal neurons

Rat post-mitotic septal neurons, engineered to proliferate and arrest under physiological conditions can be maintained for weeks without cytotoxic effects. Nine independent cDNA libraries were made to follow arrest-induced neural differentiation and innate immune responses in normal uninfected and CJ agent infected septal neurons for weeks. CJ infection created a non-productive latent (CJ-) and a productive (CJ+) high infectivity model (10 logs/gm). Arrest of normal uninfected cells upregulated a plethora of anti-proliferative transcripts and known neuronal differentiation transcripts (e.g., Agtr2, Neuregulin-1, GDF6, SFRP4 and Prnp). Notably, many activated IFN innate immune genes were simultaneously upregulated (e.g., OAS1, RTP4, ISG20, GTB4, CD80, cytokines, chemokines and complement) along with clusterin (CLU) that binds misfolded proteins. Arrest of latently infected CJ-cells induced even more profound global transcript differences. CJ+ cells markedly downregulated the anti-proliferative controls seen in arrested normal cells. CJ+ infection also suppressed neuronal differentiation transcripts, including Prnp which is essential for CJ agent infection. Additionally, IFN and cytokine/chemokine pathways were also strongly enhanced. Analysis of the 342 CJ+ unique transcripts revealed additional innate immune and anti-viral-linked transcripts, e.g., Il17, ISG15, and RSAD2 (viperin). These data show: 1) innate immune transcripts are produced by normal neurons during differentiation; 2) CJ infection enhances and expands anti-viral responses; 3) non-productive latent infection can epigenetically imprint many proliferative pathways to thwart complete arrest. Consequently, human blood and intestinal myeloid peripheral cells that are latently infected (silent) for many years may be stimulated in vitro to produce CJ+ linked diagnostic transcripts.

neuroscience↗

bioRxiv2024

Loss of cell junctional components and matrix alterations drive cell desquamation and fibrotic changes in Idiopathic Pulmonary Fibrosis

The distal bronchioles in Idiopathic Pulmonary Fibrosis (IPF) exhibit histopathological abnormalities such as bronchiolization, peribronchiolar fibrosis and honeycomb cysts that contribute to the overall architectural remodeling of lung tissue seen in the disease. Here we describe an additional histopathologic finding of epithelial desquamation in patients with IPF, wherein epithelial cells detach from the basement membrane of the distal bronchioles. To understand the mechanism driving this pathology, we performed spatial transcriptomics of the epithelial cells and spatial proteomics of the basement membrane of the distal bronchioles from IPF patients and patients with no prior history of lung disease. Our findings reveal a downregulation of cell junctional components, upregulation of epithelial-mesenchymal transition signatures and dysregulated basement membrane matrix in IPF distal bronchioles, facilitating epithelial desquamation. Further, functional assays identified regulation between Collagen IV in the matrix, and the junctional genes JUP and PLEC, that is crucial for maintaining distal bronchiolar homeostasis. In IPF, this balanced regulation between matrix and cell-junctions is disrupted, leading to loss of epithelial adhesion, peribronchiolar fibrosis and epithelial desquamation. Overall, our study suggests that in IPF the interplay between the loss of cell junctions and a dysregulated matrix results in desquamation of distal bronchiolar epithelium and lung remodeling, exacerbating the disease. One Sentence SummaryTwo-way regulation of cell junctional proteins and matrix proteins drives cellular desquamation and fibrosis in the distal bronchioles of patients with Idiopathic Pulmonary Fibrosis.

pathology↗

bioRxiv2023

Asparagine synthetase and G-protein coupled estrogen receptor are critical responders to nutrient supply in KRAS mutant colorectal cancer

The nutrient status of the tumor microenvironment has major impacts on cell growth. Under nutrient depletion, asparagine synthetase (ASNS)-mediated asparagine production increases to sustain cell survival. G protein-coupled estrogen receptor-1 (GPER1) signaling converges via cAMP/PI3K/AKT with KRAS signaling to regulate ASNS expression. However, the role of GPER1 in CRC progression is still debated, and the effect of nutrient supply on both ASNS and GPER1 relative to KRAS genotype is not well understood. Here, we modeled a restricted nutrient supply by eliminating glutamine from growing cancer cells in a 3D spheroid model of human female SW48 KRAS wild-type (WT) and KRAS G12A mutant (MT) CRC cells, to examine effects on ASNS and GPER1 expression. Glutamine depletion significantly inhibited cell growth in both KRAS MT and WT cells; however, ASNS and GPER1 were upregulated in KRAS MT compared to WT cells. When nutrient supply was adequate, ASNS and GPER1 were not altered between cell lines. The impact of estradiol, a ligand for GPER1, was examined for any additional effects on cell growth. Under glutamine deplete conditions, estradiol decreased the growth of KRAS WT cells but had no effect on KRAS MT cells; estradiol had no additive or diminutive effect on the upregulation of ASNS or GPER1 between the cell lines. We further examined the association of GPER1 and ASNS levels with overall survival in a clinical colon cancer cohort of The Cancer Genome Atlas. Both high GPER1 and ASNS expression associated with poorer overall survival for females only in advanced stage tumors. These findings suggest that KRAS MT cells have mechanisms in place that respond to decreased nutrient supply, typically observed in advanced tumors, by increasing the expression of ASNS and GPER1 to drive cell growth. Furthermore, KRAS MT cells are resistant to the protective effects of estradiol under nutrient deplete conditions. ASNS and GPER1 may therefore be potential therapeutic targets that can be exploited to manage and control KRAS MT CRC.

cancer biology↗

bioRxiv2022

Autologous humanized PDX modeling for immuno-oncology recapitulates the human tumor microenvironment

Interactions between immune and tumor cells are critical to determining cancer progression and response. In addition, preclinical prediction of immune-related drug efficacy is limited by inter-species differences between human and mouse, as well as inter-person germline and somatic variation. Here we develop an autologous system that models the TME in individual patients. With patient-derived bone marrow, we engrafted a patients hematopoietic system in MISTRG6 mice followed by patient-derived xenograft (PDX) tissue, providing a genetically matched autologous model. We used this system to prospectively study tumor-immune interactions in solid tumor patients. Autologous PDX mice generated innate and adaptive immune populations; these cells populated the TME; and tumors from autologously engrafted mice grew larger than tumors from non-engrafted littermate controls. Single-cell transcriptomics revealed a prominent VEGF-A signature in TME myeloid cells, and inhibition of human VEGF-A abrogated enhanced growth, demonstrating the utility of the autologous PDX system for pre-clinical testing.

cancer biology↗

bioRxiv2022

Bone marrow age dictates clonality of smooth muscle-derived cells in the atherosclerotic plaque

Aging is the predominant risk factor for atherosclerosis, the leading cause of death. Rare smooth muscle cell (SMC) progenitors clonally expand giving rise to up to [~]70% of atherosclerotic plaque cells; however, the effect of age on SMC clonality is not known. Our results indicate that aged bone marrow (BM)-derived cells non-cell autonomously induce SMC polyclonality and worsen atherosclerosis. Indeed, in myeloid cells from aged mice and humans, TET2 levels are reduced which epigenetically silences integrin {beta}3 resulting in increased tumor necrosis factor [TNF]- signaling. In turn, TNF signals through TNF receptor 1 on SMCs to promote proliferation and induces recruitment and expansion of multiple SMC progenitors into the atherosclerotic plaque. Notably, integrin {beta}3 overexpression in aged BM preserves dominance of the lineage of a single SMC progenitor and attenuates plaque burden. Our results demonstrate a molecular mechanism of aged macrophage-induced SMC polyclonality and atherogenesis and suggest novel therapeutic strategies. Graphical abstractAge of BM-derived monocytes/macrophages determines clonality of SMC lineage in the atherosclerotic plaque. Atherogenesis is depicted in a young (a) or aged (b) host. Aged monocytes/macrophages have decreased levels of the epigenetic regulator TET2, leading to reduction of the 5-hydroxymethylcytosine (5hmC) mark on the Itgb3 promoter. The resulting low integrin {beta}3 levels in aged monocytes/macrophages induces high TNF- levels, facilitating recruitment and expansion of multiple SMC progenitors (polyclonality) in the atherosclerotic plaque and worse disease burden. In contrast, the young control is characterized by mono/oligoclonal SMC expansion in a smaller plaque. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=135 SRC="FIGDIR/small/476756v2_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@12f7090org.highwire.dtl.DTLVardef@186ff92org.highwire.dtl.DTLVardef@1f4da69org.highwire.dtl.DTLVardef@2f509c_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2021

Peer teaching as bioinformatics training strategy: incentives, challenges, and benefits.

As biomedical research becomes more data-intensive, bioinformatics is becoming essential to understanding biological processes, systems, and diseases. In this paper we describe the use of a series of peer teaching workshops as a strategy to respond to the bioinformatics training needs at a research-intensive institution. In addition to the data collected from the workshops, we also used personal experiences of researchers who participated as peer teachers to understand the incentives, challenges, and benefits of peer teaching. Developing communication skills such as confidence in teaching, explaining complex concepts, and better understanding of the topic emerged as primary benefits that the teachers obtained from this experience. Lack of time for teaching and the struggles of classroom management were identified as two major challenges. We suggest that peer teaching can be beneficial not only to train researchers in bioinformatics, but also as a professional development opportunity for graduate students and postdoctoral trainees.

scientific communication and education↗

bioRxiv2020

Novel insights into the mode of action of 1,4-dioxane using a systems screening approach

1,4-Dioxane (1,4-DX) is an environmental contaminant found in drinking water throughout the United States (US). While it is a suspected liver carcinogen, there is no federal or state maximum contaminant level for 1,4-DX in drinking water. Very little is known about the mechanisms by which this chemical elicits liver carcinogenicity. In the present study, female BDF-1 mice were exposed to 1,4-DX (0, 50, 500 and 5,000 mg/L) in their drinking water for one or four weeks, to explore the toxic effects. Histopathological studies and a multi-omics approach (transcriptomics and metabolomics) were performed to investigate potential mechanisms of toxicity. Immunohistochemical analysis of the liver revealed increased H2AX{gamma}-positive hepatocytes (a marker of DNA double strand breaks), and an expansion of precholangiocytes (reflecting both DNA damage and repair mechanisms) after exposure. Liver transcriptomics revealed 1,4-DX-induced perturbations in signaling pathways predicted to impact the oxidative stress response, detoxification, and DNA damage. Liver, kidney, feces and urine metabolomic profiling revealed no effect of 1,4-DX exposure, and bile acid quantification in liver and feces similarly showed no effect of exposure. We speculate that the results may be reflective of DNA damage being counterbalanced by the repair response, with the net result being a null overall effect on the systemic biochemistry of the exposed mice. Our results show a novel approach for the investigation of environmental chemicals that do not elicit cell death but have activated the repair systems in response to 1,4-DX exposure.

pharmacology and toxicology↗

bioRxiv2019

Molecular pathway analysis indicates a distinct metabolic and immune phenotype in women with right-sided colon cancer

Colon cancer is the third most commonly diagnosed cancer in the United States. Recent reports have shown that the location of the primary tumor is of clinical importance. Patients with right-sided cancers (RCCs) (tumors arising between the cecum and proximal transverse colon) have poorer clinical outcomes than those with left-sided colon cancers (LCCs) (tumors arising between the distal transverse colon and sigmoid colon, excluding the rectum). Interestingly, women have a lower incidence of colon cancer than men do. However, women have a higher propensity for RCC than men. Identification of gene expression differences between RCC and LCC is considered a potential means of prognostication. Furthermore, studying colon cancer sidedness could reveal important predictive markers for response to various treatments. This study provides a comprehensive bioinformatic analysis of various genes and molecular pathways that correlated with sex and anatomical location of colon cancer using four publicly available annotated datasets housed in the National Center for Biotechnology Informations Gene Expression Omnibus (GEO). We identified differentially expressed genes in tumor tissues from women with RCC, which showed attenuated energy and nutrient metabolism when compared to women with LCC. Specifically, we showed that the downregulation of 5 AMP-activated protein kinase alpha subunit (AMPK) and downregulated anti-tumor immune response in women with RCC. This difference was not seen when comparing tumor tissues from men with RCC to men with LCC. Therefore, women with RCC may have a specific metabolic and immune phenotype which accounts for differences in prognosis and treatment response.

cell biology↗