Gliomas are highly aggressive and accompanied by numerous microglia/macrophages (MG/MP) in and about the tumor. Little is known about what MG/MP do in this setting, or whether modulating MG/MP activation might affect glioma progression. Here, we used a glioma-microglia in culture system to establish the effects the tumor and microglia have on each other. We assessed glioma progression in vivo after MG/MP ablation or in the setting of exaggerated MG/MP activation. We show that glioma cells activate microglia but inhibit their phagocytic activities. Local ablation of MG/MP in vivo decreased tumor size and improved survival curves. Conversely, pharmacological activation of MG/MP increased glioma size through stimulating tumor proliferation and inhibiting apoptosis.
Wikipedia talk:WikiProject Chemistry/CAS validation/CAS-German Wikipedia From Wikipedia, the free encyclopedia. 4320-01-353-2977 A positive displacement device which utilzes the rotating motion of one or more gears, cams, vanes, or screws in an enclosure as a means of transferring a liquid from one place to another. It is designed to be driven manually or by a prime mover which is not an integral part of the pump. Excludes aircraft engine pumps.
In agreement with recent reports, expression of the chemokine CCL21 is enhanced after MG/MP activation and correlates with tumor growth. Taken together, our findings demonstrate that inhibition of MG/MP activation may constitute a new and effective contribution towards suppressing glioma proliferation.
Introduction Malignant gliomas are primary central nervous system (CNS) tumors arising from glial cells and are one of the deadliest cancers - median survival time is one year even with aggressive surgical resection combined with irradiation and chemotherapy. Although many therapeutic approaches have been explored, there has been no major improvement in survival over the last 30 years (; ). Gliomas are infiltrated by MG/MP, and the extent of MG/MP infiltration correlates positively with malignancy (;; ). Microglia are capable of antigen presentation to T cells patrolling the CNS (). Upon injury, microglia undergo activation characterized by changes in morphology, gene expression, proliferation, phagocytic capacity, and migration towards the injury site (; ). The role of MG/MP in glioma progression remains controversial.
Materi gerbang logika. Studies reported that the immune defensive functions of glioma-infiltrating MG/MP (GIMs) are compromised. Moreover, GIMs have been proposed to promote glioma growth by secreting growth factors, immune-suppressive cytokines and angiogenic factors (;;;;; ), thus stimulating interest in therapies that modulate MG/MP activity/function. However, such approaches yielded conflicting results: injection of CpG-containing oligonucleotides, which stimulate MG/MP, induced glioma apoptosis and prolonged survival times of tumor-bearing animals in one report, whereas the same approach caused increased animal tumor size in others (; ). Here we investigate the consequences of interaction of MG/MP and glioma cells in culture using MG/MP activation and glioma cell proliferation as functional endpoints.