Non-small cell lung cancer (NSCLC) is one of the deadliest cancers worldwide. In search for new NSCLC treatment options, we screened a cationic amphiphilic drug (CAD) library for cytotoxicity against NSCLC cells and identified several CAD antihistamines as inducers of lysosomal cell death. We then performed a cohort study on the effect of CAD antihistamine use on mortality of patients diagnosed with non-localized cancer in Denmark between 1995 and 2011. The use of the most commonly prescribed CAD antihistamine, loratadine, was associated with significantly reduced all-cause mortality among patients with non-localized NSCLC or any non-localized cancer when compared with use of non-CAD antihistamines and adjusted for potential confounders. Of the less frequently described CAD antihistamines, astemizole showed a similar significant association with reduced mortality as loratadine among patients with any non-localized cancer, and ebastine use showed a similar tendency. The association between CAD antihistamine use and reduced mortality was stronger among patients with records of concurrent chemotherapy than among those without such records. In line with this, sub-micromolar concentrations of loratadine, astemizole and ebastine sensitized NSCLC cells to chemotherapy and reverted multidrug resistance in NSCLC, breast and prostate cancer cells. Thus, CAD antihistamines may improve the efficacy of cancer chemotherapy.

Repurposing cationic amphiphilic drugs (CAD) for cancer treatment is emerging as an attractive means to enhance the efficacy of chemotherapy. Many commonly used CADs, including several cation amphiphilic antihistamines and antidepressants, induce cancer-specific, lysosome-dependent cell death and sensitize cancer cells to chemotherapy. CAD-induced inhibition of lysosomal acid sphingomyelinase is necessary, but not sufficient, for the subsequent lysosomal membrane permeabilization and cell death, while other pathways regulating this cell death pathway are largely unknown. Prompted by significant changes in the expression of genes involved in Ca2+ and cyclic AMP (cAMP) signaling pathways in CAD-resistant MCF7 breast cancer cells, we identified here an early lysosomal Ca2+ release through P2X purinergic receptor 4 (P2RX4) and subsequent Ca2+- and adenylyl cyclase 1 (ADCY1)-dependent synthesis of cAMP as a signaling route mediating CAD-induced lysosomal membrane permeabilization and cell death. Importantly, pharmacologic and genetic means to increase cellular cAMP levels either by activating cAMP-inducing G-protein–coupled receptors (GPR3 or β2 adrenergic receptor) or ADCY1, or by inhibiting cAMP-reducing guanine nucleotide-binding protein G(i) subunit α2, C-X-C motif chemokine receptor type 4, or cAMP phosphodiesterases, sensitized cancer cells to CADs. These data reveal a previously unrecognized lysosomal P2RX4- and ADCY1-dependent signaling cascade as a pathway essential for CAD-induced lysosome-dependent cell death and encourage further investigations to find the most potent combinations of CADs and cAMP-inducing drugs for cancer therapy.

This international consensus statement synthesizes key findings on the complex roles of microglia and macrophages (tumor-associated microglia/macrophages or TAMs) in glioma progression and therapeutic resistance. Recent advances have highlighted the cellular, spatial, and temporal heterogeneity of TAMs, their functional plasticity, and the intricate interactions between TAMs, glioma stem cells, and the neuronal microenvironment, challenging the M1/M2 classification paradigm for TAMs in gliomas and other misconceptions. The statement emphasizes that glioma cells manipulate TAMs to suppress anti-tumor functions, while microglia-mediated modulation of neuron-glioma cell interactions promotes tumor progression. Furthermore, glioblastoma-derived extracellular vesicles (EVs) reprogram microglia to support tumor progression, offering novel therapeutic targets. To advance research and develop more effective treatments, the statement advocates for precision therapies targeting specific TAM subsets or functions, the use of bioengineered EVs as a therapeutic approach, and a shift away from simplistic terminology like “M1/M2” and “neuroinflammation”. Ultimately, this new understanding can support innovative strategies to modulate the tumor microenvironment, turning immunosuppression into immunostimulation and improving outcomes for patients with glioblastoma and other types of gliomas.

Background: Glioblastoma undergoes a complex and dynamic evolution involving genetic and epigenetic changes. Understanding the mechanisms underlying this evolution is vital for the development of efficient therapeutic strategies. Although treatment resistance is associated with intratumoral heterogeneity in glioblastoma, it remains uncertain whether hypometabolic and hypermetabolic lesions observed through clinical positron emission tomography (PET) imaging are influenced by spatial intratumoral genomic evolution. Methods: In this study, we precisely isolated autologous hypometabolic and hypermetabolic lesions from glioblastoma using advanced neurosurgical and brain tumor imaging technologies, followed by comprehensive whole-genome, exome, transcriptome, and imaging analyses. Results: Our findings unveil that hypermetabolic lesions, originating from hypometabolic lesions, exhibit strategic focal amplifications and deletions, and heightened APOBEC3 activity. Furthermore, we identify dipeptidase 1 as a novel vascular endothelial tip marker for hypermetabolic lesions in glioblastoma, facilitating angiogenesis and tumor metabolism by regulating transporter activities. Conclusions: Hypermetabolic lesions are associated with a higher frequency of genomic abnormalities and dipeptidase 1 emerges as a novel diagnostic and prognostic vascular marker for hypermetabolic lesions. This study underscores a spatial genomic evolution with diagnostic implications and elucidates challenges and opportunities crucial for the development of novel therapeutic strategies.

Glioblastoma undergoes a complex and dynamic evolution involving genetic and epigenetic changes. Understanding the mechanisms underlying this evolution is vital for the development of efficient therapeutic strategies. Although treatment resistance is associated with intratumoral heterogeneity in glioblastoma, it remains uncertain whether hypometabolic and hypermetabolic lesions observed through positron emission tomography (PET) imaging are influenced by spatial intratumoral genomic evolution. In this study, we precisely isolated autologous hypometabolic and hypermetabolic lesions from glioblastoma using advanced neurosurgical and brain tumor imaging technologies, followed by comprehensive whole-genome exome and transcriptome analyses. Our findings revealed that hypermetabolic lesions evolved from hypometabolic lesions, harbored shrewd focal amplifications and deletions, and exhibited a higher frequency of critical genomic alterations linked to increased aggressiveness, upregulated APOBEC3 and hypoxic genes, and downregulated putative tumor suppressors. This study highlights spatial genomic evolution with diagnostic implications and unveils the obstacles and possibilities that should be considered in the development of novel therapeutic strategies. Statement of significance: Glioblastoma is a multifaceted disease that is difficult to treat, and insights into the metabolic gradient observed in imaging and the underlying role of genomic evolution are lacking. This study is the first to investigate the molecular basis of hypermetabolic tumor lesions in glioblastoma using precise three-dimensional biopsy isolation, whole genome/exome, and mRNA sequencing. These findings have diagnostic significance, provide insights into therapeutic resistance, and shed light on the obstacles encountered by precision therapeutics for glioblastoma.