The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points.
a b s t r a c tAlterations in the levels of molecules which interact with the extracellular matrix, such as integrins, are associated with invasion of oral squamous cell carcinomas (OSCC). The molecular mechanisms underlying dysregulation of integrin expression in OSCC, however, remain unclear. Here, we show that microRNA-124, a small non-coding RNA down-regulated in OSCC, is able to downregulate expression of integrin beta-1 (ITGB1) by interacting with its 3 0 untranslated region. Over-expression of miR-124 attenuates endogenous ITGB1 expression and reduces the adherence and motility of OSCC cells, suggesting disruption of miR-124-mediated repression of ITGB1 may be a key factor in OSCC progression.
The efficacy of current anti-cancer gene therapies is limited by the inability of gene vectors to penetrate the poorly vascularized, hypoxic regions of tumors, leaving these sites untreated. We describe a new approach for targeting gene therapy to these sites, which employs an attenuated strain of the non-pathogenic bacterium, Salmonella typhimurium, carrying an exogenous (that is, reporter or therapeutic) gene under the regulation of a new, highly hypoxia-inducible promoter (FF+20 *). This bacterial vector was seen to rapidly migrate into, and thrive in, hypoxic areas of both mammary tumor spheroids grown in vitro and orthotopic mammary tumors after systemic injection. Using the reporter gene construct, FF+20 *-lacZ, we show that bacterial expression of high levels of b-galactosidase occurred only in hypoxic/necrotic sites of spheroids and tumors. We then replaced the reporter gene with one encoding a novel cytotoxic protein (HlyE) and showed that this was also expressed by bacteria only in hypoxic regions of murine mammary tumors. This resulted in a marked increase in tumor necrosis and reduced tumor growth. Our system represents a promising new strategy for delivering gene therapy to poorly vascularized regions of tumors and shows, for the first time, the efficacy of HlyE as an anti-tumor agent.
N,N,N,N-tetrakis(2-pyridylmethyl)ethylenediamine.
The role of extracellular vesicles (EVs) as vehicles for cell-to-cell communication between a tumour and its environment is a relatively new concept. The hypothesis that EVs may be critical in co-opting tissues by tumours to generate distant metastatic niches is particularly pertinent to prostate cancer (PCa), where metastatic-tropism to bone predominates over other tissue types. The potential role of EVs as a means of communication between PCa cells and cells of the bone stroma such as osteoblasts, is yet to be fully explored. In this study, we demonstrate that PCa cell EVs both enhance osteoblast viability and produce a significantly more supportive growth environment for PCa cells when grown in co-culture with EV-treated osteoblasts ( p < 0.005). Characterisation of the RNA cargo of EVs produced by the bone-metastatic PCa cell line PC3, highlights the EV-RNA cargo is significantly enriched in genes relating to cell surface signalling, cell–cell interaction, and protein translation ( p < 0.01). Using novel techniques to track RNA, we demonstrate the delivery of a set of PCa-RNAs to osteoblast via PCa-EVs and show the effect on osteoblast endogenous transcript abundance. Taken together, by using proof-of-concept studies we demonstrate for the first time the contribution of the RNA element of the PCa EV cargo, providing evidence to support PCa EV communication via RNA molecules as a potential novel route to mediate bone metastasis. We propose targeting PCa EVs could offer a potentially important preventative therapy for men at risk of metastatic PCa.
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.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.