BACKGROUND: The coronavirus disease of 2019 (COVID-19), which is caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently been designated a pandemic by the World Health Organization, affecting 2.7 million individuals globally as of April 25, 2020, with more than 187,000 deaths. An increasing body of evidence has supported central nervous system involvement.-METHODS: We conducted a review of the reported data for studies concerning COVID-19 pathophysiology, neurological manifestations, and neuroscience provider recommendations and guidelines.-RESULTS: Central nervous system manifestations range from vague nonfocal complaints to severe neurological impairment associated with encephalitis. It is unclear whether the neurological dysfunction results from direct viral injury or systemic disease. The virus could affect brainstem pathways that lead to indirect respiratory dysfunction, in addition to direct pulmonary injury. Necessary adaptations in patient management, triage, and diagnosis are evolving in light of the ongoing scientific and clinical findings.-CONCLUSIONS: The present review has consolidated the current body of data regarding the neurological impact of coronaviruses, discussed the reported neurological manifestations of COVID-19, and highlighted the recommendations for patient management. Specific recommendations pertaining to clinical practice for neurologists and neurosurgeons have also been provided.
It is well established that the tumor microenvironment plays an important role in cancer development and progression. The tumor microenvironment is composed of neoplastic cells, endothelial cells, pericytes, adipocytes, fibroblasts and other connective tissue cells, extracellular matrix components, multiple stem and progenitor cells, and a diverse array of innate and adaptive immune cells [Nat Rev Cancer 2007;7:139–147]. Understanding the mechanisms behind cell–cell communication in the tumor microenvironment is critical to understanding the drivers of tumorigenesis and metastasis. In this review, we discuss the interactions between adipose stem cells, a critical component of the tumor microenvironment, and various forms of cancer. Stem Cells 2019;37:1261–1266
Adipose stem cells (ASCs) play an essential role in tumor microenvironments. These cells are altered by obesity (obASCs) and previous studies have shown that obASCs secrete higher levels of leptin. Increased leptin, which upregulates estrogen receptor alpha (ERα) and aromatase, enhances estrogen bioavailability and signaling in estrogen receptor positive (ER+) breast cancer (BC) tumor growth and metastasis. In this study, we evaluate the effect of obASCs on ER+BC outside of the ERα signaling axis using breast cancer models with constitutively active ERα resulting from clinically relevant mutations (Y537S and D538G). We found that while obASCs promote tumor growth and proliferation, it occurs mostly through abrogated estrogen signaling when BC has constitutive ER activity. However, obASCs have a similar promotion of metastasis irrespective of ER status, demonstrating that obASC promotion of metastasis may not be completely estrogen dependent. We found that obASCs upregulate two genes in both ER wild type (WT) and ER mutant (MUT) BC: SERPINE1 and ABCB1. This study demonstrates that obASCs promote metastasis in ER WT and MUT xenografts and an ER MUT patient derived xenograft (PDX) model. However, obASCs promote tumor growth only in ER WT xenografts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.