The Benedict Arnold of the Central Nervous System Tumor Microenvironment? The Role of Microglia/Macrophages in Glioma

Nanocarriers for the treatment of glioblastoma multiforme: A succinct review of conventional and repositioned drugs in the last decade

Glioblastoma multiforme is a very combative and threatening type of cancer. The standard course of treatment involves excising the tumor surgically, then administering chemotherapy and radiation therapy. Because of the presence of the blood-brain barrier and the unique characteristics of the tumor microenvironment, chemotherapy is extremely difficult and has a high incidence of relapse. With their capacity to precisely target and transport therapeutic medications to the tumor while overcoming the challenges provided by invasive and infiltrative gliomas, nanocarriers offer a potentially beneficial treatment option for gliomas. Drug repositioning or, in other words, finding novel therapeutic uses for medications that have received approval for previous uses has also recently emerged to provide alternative treatments for many diseases, with glioblastoma being among them. In this article, our goal is to shed light on the pathogenesis of glioma and summarize the proposed treatment approaches in the last decade, highlighting how combining repositioned drugs and nanocarriers technology can reduce drug resistance and improve therapeutic efficacy in primary glioma.

LAT1, a novel pharmacological target for the treatment of glioblastoma

The L-Type Amino Acid transporter, LAT1 (SLC7A5), has a crucial role in mediating amino acid uptake into the cells, thus modulating cell growth and proliferation as well as other intracellular functions. Different studies have reported a central role of LAT1 in glioblastoma development and progression, suggesting that the modulation of its activity could be a novel therapeutic strategy. LAT1 also has an important role in the peripheral immune system, by regulating the activation status of several immune cells through modulation of the mechanistic target of rapamycin kinase. In glioblastoma (GBM), the blood-brain barrier is disrupted, which allows the recruitment of peripheral immune cells to the tumour site. These cells, together with resident microglia, contribute to cancer growth and progression. Currently, little is known about the function of LAT1 in the reprogramming of the immune component of the tumour microenvironment in the context of GBM. In this article, we review the available data on the role of LAT1 in the regulation of GBM biology, including its potential role in the tumour microenvironment, particularly in infiltrating-peripheral immune cells and resident microglial cells. In addition, we review the available data on the main pharmacological inhibitors of LAT1, aiming to evaluate their possible role as novel therapeutics for GBM.