IU Indianapolis ScholarWorks :: Browsing by Author "Zhang, Siyuan"

Browsing by Author "Zhang, Siyuan"

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Aged Breast Extracellular Matrix Drives Mammary Epithelial Cells to an Invasive and Cancer-Like Phenotype
(Wiley, 2021-11) Bahcecioglu, Gokhan; Yue, Xiaoshan; Howe, Erin; Guldner, Ian; Stack, M. Sharon; Nakshatri, Harikrishna; Zhang, Siyuan; Zorlutuna, Pinar; Surgery, School of Medicine
Age is a major risk factor for cancer. While the importance of age related genetic alterations in cells on cancer progression is well documented, the effect of aging extracellular matrix (ECM) has been overlooked. This study shows that the aging breast ECM alone is sufficient to drive normal human mammary epithelial cells (KTB21) to a more invasive and cancer‐like phenotype, while promoting motility and invasiveness in MDA‐MB‐231 cells. Decellularized breast matrix from aged mice leads to loss of E‐cadherin membrane localization in KTB21 cells, increased cell motility and invasion, and increased production of inflammatory cytokines and cancer‐related proteins. The aged matrix upregulates cancer‐related genes in KTB21 cells and enriches a cell subpopulation highly expressing epithelial‐mesenchymal transition‐related genes. Lysyl oxidase knockdown reverts the aged matrix‐induced changes to the young levels; it relocalizes E‐cadherin to cell membrane, and reduces cell motility, invasion, and cytokine production. These results show for the first time that the aging ECM harbors key biochemical, physical, and mechanical cues contributing to invasive and cancer‐like behavior in healthy and cancer mammary cells. Differential response of cells to young and aged ECMs can lead to identification of new targets for cancer treatment and prevention.
CNS-Native Myeloid Cells Drive Immune Suppression in the Brain Metastatic Niche through Cxcl10
(Cell Press, 2020) Guldner, Ian H.; Wang, Qingfei; Yang, Lin; Golomb, Samantha M.; Zhao, Zhuo; Lopez, Jacqueline A.; Brunory, Abigail; Howe, Erin N.; Zhang, Yizhe; Palakurthi, Bhavana; Barron, Martin; Gao, Hongyu; Xuei, Xiaoling; Liu, Yunlong; Li, Jun; Chen, Danny Z.; Landreth, Gary E.; Zhang, Siyuan; Medical and Molecular Genetics, School of Medicine
Brain metastasis (br-met) develops in an immunologically unique br-met niche. Central nervous system-native myeloid cells (CNS-myeloids) and bone-marrow-derived myeloid cells (BMDMs) cooperatively regulate brain immunity. The phenotypic heterogeneity and specific roles of these myeloid subsets in shaping the br-met niche to regulate br-met outgrowth have not been fully revealed. Applying multimodal single-cell analyses, we elucidated a heterogeneous but spatially defined CNS-myeloid response during br-met outgrowth. We found Ccr2+ BMDMs minimally influenced br-met while CNS-myeloid promoted br-met outgrowth. Additionally, br-met-associated CNS-myeloid exhibited downregulation of Cx3cr1. Cx3cr1 knockout in CNS-myeloid increased br-met incidence, leading to an enriched interferon response signature and Cxcl10 upregulation. Significantly, neutralization of Cxcl10 reduced br-met, while rCxcl10 increased br-met and recruited VISTAHi PD-L1+ CNS-myeloid to br-met lesions. Inhibiting VISTA- and PD-L1-signaling relieved immune suppression and reduced br-met burden. Our results demonstrate that loss of Cx3cr1 in CNS-myeloid triggers a Cxcl10-mediated vicious cycle, cultivating a br-met-promoting, immune-suppressive niche.
Death effector domain-containing protein induces vulnerability to cell cycle inhibition in triple-negative breast cancer
(Springer Nature, 2019-06-28) Ni, Yingjia; Schmidt, Keon R.; Werner, Barnes A.; Koenig, Jenna K.; Guldner, Ian H.; Schnepp, Patricia M.; Tan, Xuejuan; Jiang, Lan; Host, Misha; Sun, Longhua; Howe, Erin N.; Wu, Junmin; Littlepage, Laurie E.; Nakshatri, Harikrishna; Zhang, Siyuan; Surgery, IU School of Medicine
Lacking targetable molecular drivers, triple-negative breast cancer (TNBC) is the most clinically challenging subtype of breast cancer. In this study, we reveal that Death Effector Domain-containing DNA-binding protein (DEDD), which is overexpressed in > 60% of TNBCs, drives a mitogen-independent G1/S cell cycle transition through cytoplasm localization. The gain of cytosolic DEDD enhances cyclin D1 expression by interacting with heat shock 71 kDa protein 8 (HSC70). Concurrently, DEDD interacts with Rb family proteins and promotes their proteasome-mediated degradation. DEDD overexpression renders TNBCs vulnerable to cell cycle inhibition. Patients with TNBC have been excluded from CDK 4/6 inhibitor clinical trials due to the perceived high frequency of Rb-loss in TNBCs. Interestingly, our study demonstrated that, irrespective of Rb status, TNBCs with DEDD overexpression exhibit a DEDD-dependent vulnerability to combinatorial treatment with CDK4/6 inhibitor and EGFR inhibitor in vitro and in vivo. Thus, our study provided a rationale for the clinical application of CDK4/6 inhibitor combinatorial regimens for patients with TNBC.
Engineering bioactive nanoparticles to rejuvenate vascular progenitor cells
(Springer Nature, 2022-06-29) Bui, Loan; Edwards, Shanique; Hall, Eva; Alderfer, Laura; Round, Kellen; Owen, Madeline; Sainaghi, Pietro; Zhang, Siyuan; Nallathamby, Prakash D.; Haneline, Laura S.; Hanjaya-Putra, Donny; Pediatrics, School of Medicine
Fetal exposure to gestational diabetes mellitus (GDM) predisposes children to future health complications including type-2 diabetes mellitus, hypertension, and cardiovascular disease. A key mechanism by which these complications occur is through stress-induced dysfunction of endothelial progenitor cells (EPCs), including endothelial colony-forming cells (ECFCs). Although several approaches have been previously explored to restore endothelial function, their widespread adoption remains tampered by systemic side effects of adjuvant drugs and unintended immune response of gene therapies. Here, we report a strategy to rejuvenate circulating vascular progenitor cells by conjugation of drug-loaded liposomal nanoparticles directly to the surface of GDM-exposed ECFCs (GDM-ECFCs). Bioactive nanoparticles can be robustly conjugated to the surface of ECFCs without altering cell viability and key progenitor phenotypes. Moreover, controlled delivery of therapeutic drugs to GDM-ECFCs is able to normalize transgelin (TAGLN) expression and improve cell migration, which is a critical key step in establishing functional vascular networks. More importantly, sustained pseudo-autocrine stimulation with bioactive nanoparticles is able to improve in vitro and in vivo vasculogenesis of GDM-ECFCs. Collectively, these findings highlight a simple, yet promising strategy to rejuvenate GDM-ECFCs and improve their therapeutic potential. Promising results from this study warrant future investigations on the prospect of the proposed strategy to improve dysfunctional vascular progenitor cells in the context of other chronic diseases, which has broad implications for addressing various cardiovascular complications, as well as advancing tissue repair and regenerative medicine.
GAD1 Upregulation Programs Aggressive Features of Cancer Cell Metabolism in the Brain Metastatic Microenvironment
(American Association for Cancer Research, 2017-06-01) Schnepp, Patricia M.; Lee, Dennis D.; Guldner, Ian H.; O'Tighearnaigh, Treasa K.; Howe, Erin N.; Palakurthi, Bhavana; Eckert, Kaitlyn E.; Toni, Tiffany A.; Ashfeld, Brandon L.; Zhang, Siyuan; Medicine, School of Medicine
The impact of altered amino acid metabolism on cancer progression is not fully understood. We hypothesized that a metabolic transcriptome shift during metastatic evolution is crucial for brain metastasis. Here, we report a powerful impact in this setting caused by epigenetic upregulation of glutamate decarboxylase 1 (GAD1), a regulator of the GABA neurotransmitter metabolic pathway. In cell-based culture and brain metastasis models, we found that downregulation of the DNA methyltransferase DNMT1 induced by the brain microenvironment-derived clusterin resulted in decreased GAD1 promoter methylation and subsequent upregulation of GAD1 expression in brain metastatic tumor cells. In a system to dynamically visualize cellular metabolic responses mediated by GAD1, we monitored the cytosolic NADH:NAD+ equilibrium in tumor cells. Reducing GAD1 in metastatic cells by primary glia cell coculture abolished the capacity of metastatic cells to utilize extracellular glutamine, leading to cytosolic accumulation of NADH and increased oxidative status. Similarly, genetic or pharmacologic disruption of the GABA metabolic pathway decreased the incidence of brain metastasis in vivo Taken together, our results show how epigenetic changes in GAD1 expression alter local glutamate metabolism in the brain metastatic microenvironment, contributing to a metabolic adaption that facilitates metastasis outgrowth in that setting.
Generating intravital super-resolution movies with conventional microscopy reveals actin dynamics that construct pioneer axons
(The Company of Biologists, 2019-03-08) Zhang, Yide; Nichols, Evan L.; Zellmer, Abigail M.; Guldner, Ian H.; Kankel, Cody; Zhang, Siyuan; Howard, Scott S.; Smith, Cody J.; Medicine, School of Medicine
Super-resolution microscopy is broadening our in-depth understanding of cellular structure. However, super-resolution approaches are limited, for numerous reasons, from utilization in longer-term intravital imaging. We devised a combinatorial imaging technique that combines deconvolution with stepwise optical saturation microscopy (DeSOS) to circumvent this issue and image cells in their native physiological environment. Other than a traditional confocal or two-photon microscope, this approach requires no additional hardware. Here, we provide an open-access application to obtain DeSOS images from conventional microscope images obtained at low excitation powers. We show that DeSOS can be used in time-lapse imaging to generate super-resolution movies in zebrafish. DeSOS was also validated in live mice. These movies uncover that actin structures dynamically remodel to produce a single pioneer axon in a 'top-down' scaffolding event. Further, we identify an F-actin population - stable base clusters - that orchestrate that scaffolding event. We then identify that activation of Rac1 in pioneer axons destabilizes stable base clusters and disrupts pioneer axon formation. The ease of acquisition and processing with this approach provides a universal technique for biologists to answer questions in living animals.
The glutathione peroxidase Gpx4 prevents lipid peroxidation and ferroptosis to sustain Treg cell activation and suppression of antitumor immunity
(Elsevier, 2021-06) Xu, Chengxian; Sun, Shaogang; Johnson, Travis; Qi, Rong; Zhang, Siyuan; Zhang, Jie; Yang, Kai; Pediatrics, School of Medicine
T regulatory (Treg) cells are crucial to maintain immune tolerance and repress antitumor immunity, but the mechanisms governing their cellular redox homeostasis remain elusive. We report that glutathione peroxidase 4 (Gpx4) prevents Treg cells from lipid peroxidation and ferroptosis in regulating immune homeostasis and antitumor immunity. Treg-specific deletion of Gpx4 impairs immune homeostasis without substantially affecting survival of Treg cells at steady state. Loss of Gpx4 results in excessive accumulation of lipid peroxides and ferroptosis of Treg cells upon T cell receptor (TCR)/CD28 co-stimulation. Neutralization of lipid peroxides and blockade of iron availability rescue ferroptosis of Gpx4-deficient Treg cells. Moreover, Gpx4-deficient Treg cells elevate generation of mitochondrial superoxide and production of interleukin-1β (IL-1β) that facilitates T helper 17 (TH17) responses. Furthermore, Treg-specific ablation of Gpx4 represses tumor growth and concomitantly potentiates antitumor immunity. Our studies establish a crucial role for Gpx4 in protecting activated Treg cells from lipid peroxidation and ferroptosis and offer a potential therapeutic strategy to improve cancer treatment.
Integration of molecular features with clinical information for predicting outcomes for neuroblastoma patients
(BioMed Central, 2019-08-23) Han, Yatong; Ye, Xiufen; Wang, Chao; Liu, Yusong; Zhang, Siyuan; Feng, Weixing; Huang, Kun; Zhang, Jie; Medicine, School of Medicine
BACKGROUND: Neuroblastoma is one of the most common types of pediatric cancer. In current neuroblastoma prognosis, patients can be stratified into high- and low-risk groups. Generally, more than 90% of the patients in the low-risk group will survive, while less than 50% for those with the high-risk disease will survive. Since the so-called "high-risk" patients still contain patients with mixed good and poor outcomes, more refined stratification needs to be established so that for the patients with poor outcome, they can receive prompt and individualized treatment to improve their long-term survival rate, while the patients with good outcome can avoid unnecessary over treatment. METHODS: We first mined co-expressed gene modules from microarray and RNA-seq data of neuroblastoma samples using the weighted network mining algorithm lmQCM, and summarize the resulted modules into eigengenes. Then patient similarity weight matrix was constructed with module eigengenes using two different approaches. At the last step, a consensus clustering method called Molecular Regularized Consensus Patient Stratification (MRCPS) was applied to aggregate both clinical information (clinical stage and clinical risk level) and multiple eigengene data for refined patient stratification. RESULTS: The integrative method MRCPS demonstrated superior performance to clinical staging or transcriptomic features alone for the NB cohort stratification. It successfully identified the worst prognosis group from the clinical high-risk group, with less than 40% survived in the first 50 months of diagnosis. It also identified highly differentially expressed genes between best prognosis group and worst prognosis group, which can be potential gene biomarkers for clinical testing. CONCLUSIONS: To address the need for better prognosis and facilitate personalized treatment on neuroblastoma, we modified the recently developed bioinformatics workflow MRCPS for refined patient prognosis. It integrates clinical information and molecular features such as gene co-expression for prognosis. This clustering workflow is flexible, allowing the integration of both categorical and numerical data. The results demonstrate the power of survival prognosis with this integrative analysis workflow, with superior prognostic performance to only using transcriptomic data or clinical staging/risk information alone.
Integrative analysis based on survival associated co-expression gene modules for predicting Neuroblastoma patients' survival time
(Biomed Central, 2019-02-13) Han, Yatong; Ye, Xiufen; Cheng, Jun; Zhang, Siyuan; Feng, Weixing; Han, Zhi; Zhang, Jie; Huang, Kun; Medicine, School of Medicine
BACKGROUND: More than 90% of neuroblastoma patients are cured in the low-risk group while only less than 50% for those with high-risk disease can be cured. Since the high-risk patients still have poor outcomes, we need more accurate stratification to establish an individualized precise treatment plan for the patients to improve the long-term survival rate. RESULTS: We focus on extracting features and providing a workflow to improve survival prediction for neuroblastoma patients. With a workflow for gene co-expression network (GCN) mining in microarray and RNA-Seq datasets, we extracted molecular features from each co-expressed module and summarized them into eigengenes. Then we adopted the lasso-regularized Cox proportional hazards model to select the most informative eigengene features regarding association to the risk of metastasis. Nine eigengenes were selected which show strong association with patient survival prognosis. All of the nine corresponding gene modules also have highly enriched biological functions or cytoband locations. Three of them are unique modules to RNA-Seq data, which complement the modules from microarray data in terms of survival prognosis. We then merged all eigengenes from these unique modules and used an integrative method called Similarity Network Fusion to test the prognostic power of these eigengenes for prognosis. The prognostic accuracies are significantly improved as compared to using all eigengenes, and a subgroup of patients with very poor survival rate was identified. CONCLUSIONS: We first compared GCNs mined from microarray and RNA-seq data. We discovered that each data modality yields unique GCNs, which are enriched with clear biological functions. Then we do module unique analysis and use lasso-cox model to select survival-associated eigengenes. Integration of unique and survival-associated eigengenes from both data types provides complementary information that leads to more accurate survival prognosis.
Isolation of mouse brain-infiltrating leukocytes for single cell profiling of epitopes and transcriptomes
(Elsevier, 2021-05-13) Guldner, Ian H.; Golomb, Samantha M.; Wang, Qingfei; Wang, Emilia; Zhang, Siyuan; Medicine, School of Medicine
High dimensional compositional and transcriptional profiling of heterogeneous brain-infiltrating leukocytes can lead to novel biological and therapeutic discoveries. High-quality single-cell leukocyte preparations are a prerequisite for optimal single cell profiling. Here, we describe a protocol for epitope and RNA-preserving dissociation of adult mouse brains and subsequent leukocyte purification and staining, which is adaptable to homeostatic and pathogenic brains. Leukocyte preparation following this protocol permits exquisite single-cell surface protein and RNA profiling in applications including CyTOF and CITE-seq. For complete details on the use and execution of this protocol, please refer to Guldner et al. (2020) and Golomb et al. (2020).

Browsing by Author "Zhang, Siyuan"

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