Caroline Arellano-Garcia

All Publications

• BMAL1 loss in oligodendroglia contributes to abnormal myelination and sleep. Neuron Rojo, D., Dal Cengio, L., Badner, A., Kim, S., Sakai, N., Greene, J., Dierckx, T., Mehl, L. C., Eisinger, E., Ransom, J., Arellano-Garcia, C., Gumma, M. E., Soyk, R. L., Lewis, C. M., Lam, M., Weigel, M. K., Damonte, V. M., Yalçın, B., Jones, S. E., Ollila, H. M., Nishino, S., Gibson, E. M. 2023

  Abstract

  Myelination depends on the maintenance of oligodendrocytes that arise from oligodendrocyte precursor cells (OPCs). We show that OPC-specific proliferation, morphology, and BMAL1 are time-of-day dependent. Knockout of Bmal1 in mouse OPCs during development disrupts the expression of genes associated with circadian rhythms, proliferation, density, morphology, and migration, leading to changes in OPC dynamics in a spatiotemporal manner. Furthermore, these deficits translate into thinner myelin, dysregulated cognitive and motor functions, and sleep fragmentation. OPC-specific Bmal1 loss in adulthood does not alter OPC density at baseline but impairs the remyelination of a demyelinated lesion driven by changes in OPC morphology and migration. Lastly, we show that sleep fragmentation is associated with increased prevalence of the demyelinating disorder multiple sclerosis (MS), suggesting a link between MS and sleep that requires further investigation. These findings have broad mechanistic and therapeutic implications for brain disorders that include both myelin and sleep phenotypes.

  View details for DOI 10.1016/j.neuron.2023.08.002

  View details for PubMedID 37657440

• Nonsteroidal sulfamate derivatives as new therapeutic approaches for Neurofibromatosis 2 (NF2). BMC pharmacology & toxicology Shen, Y. C., Arellano-Garcia, C. n., Menjivar, R. E., Jewett, E. M., Dohle, W. n., Karchugina, S. n., Chernoff, J. n., Potter, B. V., Barald, K. F. 2019; 20 (1): 67

  Abstract

  Neurofibromatosis 1 and 2, although involving two different tumour suppressor genes (neurofibromin and merlin, respectively), are both cancer predisposition syndromes that disproportionately affect cells of neural crest origin. New therapeutic approaches for both NF1 and NF2 are badly needed. In promising previous work we demonstrated that two non-steroidal analogues of 2-methoxy-oestradiol (2ME2), STX3451(2-(3-bromo-4,5-dimethoxybenzyl)-7-methoxy-6-sulfamoyloxy-1,2,3,4-tetrahydroisoquinoline), and STX2895 (7-Ethyl-6-sulfamoyloxy-2-(3,4,5-trimethoxybenzyl)-1,2,3,4-tetrahydroisoquinoline) reduced tumour cell growth and induced apoptosis in malignant and benign human Neurofibromatosis 1 (NF1) tumour cells. In earlier NF1 mechanism of action studies we found that in addition to their effects on non-classical hormone-sensitive pathways, STX agents acted on the actin- and myosin-cytoskeleton, as well as PI3Kinase and MTOR signaling pathways. Tumour growth in NF2 cells is affected by different inhibitors from those affecting NF1 growth pathways: specifically, NF2 cells are affected by merlin-downstream pathway inhibitors. Because Merlin, the affected tumour suppressor gene in NF2, is also known to be involved in stabilizing membrane-cytoskeletal complexes, as well as in cell proliferation, and apoptosis, we looked for potentially common mechanisms of action in the agents' effects on NF1 and NF2. We set out to determine whether STX agents could therefore also provide a prospective avenue for treatment of NF2.STX3451 and STX2895 were tested in dose-dependent studies for their effects on growth parameters of malignant and benign NF2 human tumour cell lines in vitro. The mechanisms of action of STX3451 and STX2895 were also analysed.Although neither of the agents tested affected cell growth or apoptosis in the NF2 tumour cell lines tested through the same mechanisms by which they affect these parameters in NF1 tumour cell lines, both agents disrupted actin- and myosin-based cytoskeletal structures in NF2 cell lines, with subsequent effects on growth and cell death.Both STX3451 and STX2895 provide new approaches for inducing cell death and lowering tumour burden in NF2 as well as in NF1, which both have limited treatment options.

  View details for DOI 10.1186/s40360-019-0369-8

  View details for PubMedID 31730023

• p38-mediated phosphorylation at T367 induces EZH2 cytoplasmic localization to promote breast cancer metastasis NATURE COMMUNICATIONS Anwar, T., Arellano-Garcia, C., Ropa, J., Chen, Y., Kim, H., Yoon, E., Grigsby, S., Basrur, V., Nesvizhskii, A. I., Muntean, A., Gonzalez, M. E., Kidwell, K. M., Nikolovska-Coleska, Z., Kleer, C. G. 2018; 9: 2801

  Abstract

  Overexpression of EZH2 in estrogen receptor negative (ER-) breast cancer promotes metastasis. EZH2 has been mainly studied as the catalytic component of the Polycomb Repressive Complex 2 (PRC2) that mediates gene repression by trimethylating histone H3 at lysine 27 (H3K27me3). However, how EZH2 drives metastasis despite the low H3K27me3 levels observed in ER- breast cancer is unknown. Here we show that in human invasive carcinomas and distant metastases, cytoplasmic EZH2 phosphorylated at T367 is significantly associated with ER- disease and low H3K27me3 levels. p38-mediated EZH2 phosphorylation at T367 promotes EZH2 cytoplasmic localization and potentiates EZH2 binding to vinculin and other cytoskeletal regulators of cell migration and invasion. Ectopic expression of a phospho-deficient T367A-EZH2 mutant is sufficient to inhibit EZH2 cytoplasmic expression, disrupt binding to cytoskeletal regulators, and reduce EZH2-mediated adhesion, migration, invasion, and development of spontaneous metastasis. These results point to a PRC2-independent non-canonical mechanism of EZH2 pro-metastatic function.

  View details for PubMedID 30022044

• Identification of myosin II as a cripto binding protein and regulator of cripto function in stem cells and tissue regeneration. Biochemical and biophysical research communications Hoover, M. n., Runa, F. n., Booker, E. n., Diedrich, J. K., Duell, E. n., Williams, B. n., Arellano-Garcia, C. n., Uhlendorf, T. n., La Kim, S. n., Fischer, W. n., Moresco, J. n., Gray, P. C., Kelber, J. A. 2018

  Abstract

  Cripto regulates stem cell function in normal and disease contexts via TGFbeta/activin/nodal, PI3K/Akt, MAPK and Wnt signaling. Still, the molecular mechanisms that govern these pleiotropic functions of Cripto remain poorly understood. We performed an unbiased screen for novel Cripto binding proteins using proteomics-based methods, and identified novel proteins including members of myosin II complexes, the actin cytoskeleton, the cellular stress response, and extracellular exosomes. We report that myosin II, and upstream ROCK1/2 activities are required for localization of Cripto to cytoplasm/membrane domains and its subsequent release into the conditioned media fraction of cultured cells. Functionally, we demonstrate that soluble Cripto (one-eyed pinhead in zebrafish) promotes proliferation in mesenchymal stem cells (MSCs) and stem cell-mediated wound healing in the zebrafish caudal fin model of regeneration. Notably, we demonstrate that both Cripto and myosin II inhibitors attenuated regeneration to a similar degree and in a non-additive manner. Taken together, our data present a novel role for myosin II function in regulating subcellular Cripto localization and function in stem cells and an important regulatory mechanism of tissue regeneration. Importantly, these insights may further the development of context-dependent Cripto agonists and antagonists for therapeutic benefit.

  View details for DOI 10.1016/j.bbrc.2018.12.059

  View details for PubMedID 30579599

• MMTV-cre; Ccn6 knockout mice develop tumors recapitulating human metaplastic breast carcinomas ONCOGENE Martin, E. E., Huang, W., Anwar, T., Arellano-Garcia, C., Burman, B., Guan, J., Gonzalez, M. E., Kleer, C. G. 2017; 36 (16): 2275–85

  Abstract

  Metaplastic breast carcinoma is an aggressive form of invasive breast cancer with histological evidence of epithelial to mesenchymal transition (EMT). However, the defining molecular events are unknown. Here we show that CCN6 (WISP3), a secreted matricellular protein of the CCN (CYR61/CTGF/NOV) family, is significantly downregulated in clinical samples of human spindle cell metaplastic breast carcinoma. We generated a mouse model of mammary epithelial-specific Ccn6 deletion by developing a floxed Ccn6 mouse which was bred with an MMTV-Cre mouse. Ccn6fl/fl;MMTV-Cre mice displayed severe defects in ductal branching and abnormal age-related involution compared to littermate controls. Ccn6fl/fl;MMTV-Cre mice developed invasive high grade mammary carcinomas with bona fide EMT, histologically similar to human metaplastic breast carcinomas. Global gene expression profiling of Ccn6fl/fl mammary carcinomas and comparison of orthologous genes with a human metaplastic carcinoma signature revealed a significant overlap of 87 genes (P=5 × 10-11). Among the shared deregulated genes between mouse and human are important regulators of epithelial morphogenesis including Cdh1, Ck19, Cldn3 and 4, Ddr1, and Wnt10a. These results document a causal role for Ccn6 deletion in the pathogenesis of metaplastic carcinomas with histological and molecular similarities with human disease. We provide a platform to study new targets in the diagnosis and treatment of human metaplastic carcinomas, and a new disease relevant model in which to test new treatment strategies.

  View details for DOI 10.1038/onc.2016.381

  View details for Web of Science ID 000399782700008

  View details for PubMedID 27819674

  View details for PubMedCentralID PMC5398917

• Mesenchymal Stem Cell-Induced DDR2 Mediates Stromal-Breast Cancer Interactions and Metastasis Growth CELL REPORTS Gonzalez, M. E., Martin, E. E., Anwar, T., Arellano-Garcia, C., Medhora, N., Lama, A., Chen, Y., Tanager, K. S., Yoon, E., Kidwell, K. M., Ge, C., Franceschi, R. T., Kleer, C. G. 2017; 18 (5): 1215–28

  Abstract

  Increased collagen deposition by breast cancer (BC)-associated mesenchymal stem/multipotent stromal cells (MSC) promotes metastasis, but the mechanisms are unknown. Here, we report that the collagen receptor discoidin domain receptor 2 (DDR2) is essential for stromal-BC communication. In human BC metastasis, DDR2 is concordantly upregulated in metastatic cancer and multipotent mesenchymal stromal cells. In MSCs isolated from human BC metastasis, DDR2 maintains a fibroblastic phenotype with collagen deposition and induces pathological activation of DDR2 signaling in BC cells. Loss of DDR2 in MSCs impairs their ability to promote DDR2 phosphorylation in BC cells, as well as BC cell alignment, migration, and metastasis. Female ddr2-deficient mice homozygous for the slie mutation show inefficient spontaneous BC metastasis. These results point to a role for mesenchymal stem cell DDR2 in metastasis and suggest a therapeutic approach for metastatic BC.

  View details for PubMedID 28147276