Identifying definitive biomarkers that predict clinical response and resistance to immunotherapy remains a critical challenge. One emerging factor is extracellular acidosis in the tumor microenvironment (TME), which significantly impairs immune cell function and contributes to immunotherapy failure. However, acidic conditions in the TME disrupt the interaction between cancer and immune cells, driving tumor-infiltrating T cells and NK cells into an inactivated, anergic state. Simultaneously, acidosis promotes the recruitment and activation of immunosuppressive cells, such as myeloid-derived suppressor cells and regulatory T cells (Tregs). Notably, tumor acidity enhances exosome release from Tregs, further amplifying immunosuppression. Tumor acidity thus acts as a “protective shield,” neutralizing anti-tumor immune responses and transforming immune cells into pro-tumor allies. Therefore, targeting lactate metabolism has emerged as a promising strategy to overcome this barrier, with approaches including buffer agents to neutralize acidic pH and inhibitors to block lactate production or transport, thereby restoring immune cell efficacy in the TME. Recent discoveries have identified genes involved in extracellular pH (pHe) regulation, presenting new therapeutic targets. Moreover, ongoing research aims to elucidate the molecular mechanisms driving extracellular acidification and to develop treatments that modulate pH levels to enhance immunotherapy outcomes. Additionally, future clinical studies are crucial to validate the safety and efficacy of pHe-targeted therapies in cancer patients. Thus, this review explores the regulation of pHe in the TME and its potential role in improving cancer immunotherapy.

Glioblastoma multiforme (GBM) is a highly malignant brain tumor that has a bleak outlook despite existing treatments such as surgery, radiation, and chemotherapy. The utilization of nanoparticles for drug delivery presents a promising method by which to improve the effectiveness of treatment while reducing the harmful effects on the entire body. This review examines the application of nanoparticles in the treatment of GBM, focusing on different types of nanoparticles, including lipid-based, polymeric, metallic, and those under development. Every variety is analyzed for its distinct characteristics and therapeutic capacity. Lipid-based nanoparticles, such as liposomes and solid lipid nanoparticles, enhance the transport of medicines that are not soluble in water and have shown considerable potential in preclinical investigations. Polymeric nanoparticles have benefits in terms of controlled release and targeted distribution, whereas metallic nanoparticles have potential in both therapy and imaging. In the current review we would like to emphasize the ways in which nanoparticles improve medicine delivery, specifically by enhancing penetration of the blood–brain barrier (BBB), targeting tumors, and enabling controlled release. Additionally, we also discuss current preclinical and clinical discoveries, highlighting both achievements and obstacles in the process of converting these technologies into effective treatments for GBM. This study offers a thorough examination of the present status and prospects of nanoparticles in the treatment of GBM.

Glioblastoma (GBM), the most common, invasive, and chemoresistant form of adult primary brain cancer, is characterized by rapid cell proliferation, local invasiveness, and resistance to chemotherapy (e.g., temozolomide (TMZ)) and radiation therapy. Curcumin, a bioactive polyphenol derived from Curcuma longa, has exhibited exceptional anti-cancer properties, including anti-proliferative, pro-apoptotic, anti-inflammatory, and anti-angiogenic activities in a wide range of cancer models, including GBM. However, the clinical application of curcumin has been seriously limited by several challenges, including low water solubility, low bioavailability, rapid systemic clearance, and poor blood–brain barrier (BBB) penetration. To overcome these challenges, several nanocarrier systems to produce nanocurcumin have been developed, including liposomes, polymeric nanoparticles, solid lipid nanoparticles, dendrimers, and micelles. These nanoformulations improve the solubility, stability, systemic circulation, and target-directed delivery of curcumin to glioma cells, thereby resulting in a high level of accumulation in the glioma microenvironment. On the other hand, this work is devoted to the potential of curcumin and nanocurcumin for the treatment of GBM. The article provides a detailed review of the major molecular targets of curcumin, such as NF-κB, STAT3, PI3K/AKT/mTOR, and p53 signaling pathways, as well as recent advancements in nanotechnology-based delivery platforms that improve drug delivery across the BBB and their possible clinical translation. We also include a thorough examination of the issues, limitations, and potential opportunities associated with the clinical advancement of curcumin-based therapeutics for GBM.