Research findings related to UNITE work packages A01/A03/A06/B01/B04/C01/C02

Advances in molecular understanding and diagnostic precision of glioblastoma enable the identification of key genetic alterations in a timely manner and, in principle, allow treatments with targeted compounds based on molecular markers. Here we report the results of the phase 1/2 umbrella trial NCT Neuro Master Match (N²M²), which evaluated targeted treatments in 228 patients with newly diagnosed glioblastoma without O6-methylguanine DNA-methyltransferase promoter hypermethylation. Stratification for treatment was conducted by a trial-specific molecular tumor board across five subtrials, each evaluating a targeted therapy—alectinib, idasanutlin, palbociclib, vismodegib or temsirolimus—selected according to the best-matching molecular alteration. Patients without matching alterations were randomized between subtrials without strong biomarkers using atezolizumab and asunercept, and the standard of care (SOC), temozolomide. All received radiotherapy. The primary endpoints were dose-limiting toxicities (phase 1) and progression-free survival at 6 months (PFS-6; phase 2). Secondary endpoints included safety and tolerability, as well as overall survival (OS). The subtrials for alectinib and vismodegib did not open as they did not have matching patients. The idasanutlin subtrial (n = 9) was terminated early at the discretion of the manufacturing company. The temsirolimus subtrial (n = 46) demonstrated a PFS-6 of 39.1% and median OS of 15.4 months in patients with activated mammalian target of rapamycin (mTOR) signaling compared to a PFS-6 at 18.5% in the SOC group (n = 54), meeting the primary endpoint. The atezolizumab (n = 42), asunercept (n = 26) and palbociclib (n = 41) subtrials did not meet the primary endpoint for efficacy. The safety signals of N²M² match prior experiences with the drugs in quality and quantity; no relevant negative interaction with the parallel radiotherapy was noted. The results of the N²M² trial support further investigation of temsirolimus in addition to radiotherapy in patients with newly diagnosed glioblastoma with activated mTOR signaling. ClinicalTrials.gov registration: NCT03158389.

Link to Publication

Wick W*, Lanz LM, Wick A, Harting I, Dettmer S, Suwala AK, Ketter R, Tabatabai G, Seliger C, Glas M, Burger MC, Timmer M, Ringel FA, Mildenberger I, Schulz-Schaeffer WJ, Winkler F*, König L, Herold-Mende C*, Eisenmenger A, Pfister SM*, Renovanz M, Bendszus M*, Sahm F*, Platten M*, Kessler T*. Molecularly matched targeted therapies plus radiotherapy in glioblastoma: the phase 1/2a N²M² umbrella trial. Nat Med. 2025 Oct;31(10):3534-3541. doi: 10.1038/s41591-025-03928-9. Epub 2025 Sep 5. PMID: 40913172; PMCID: PMC12532562. * UNITE Principal Investigators

Research findings related to UNITE work packages A06/A07/B06N

Glioblastomas are invasive brain tumors with high therapeutic resistance. Neuron-to-glioma synapses have been shown to promote glioblastoma progression. However, a characterization of tumor-connected neurons has been hampered by a lack of technologies. Here, we adapted retrograde tracing using rabies viruses to investigate and manipulate neuron-tumor networks. Glioblastoma rapidly integrated into neural circuits across the brain, engaging in widespread functional communication, with cholinergic neurons driving glioblastoma invasion. We uncovered patient-specific and tumor-cell-state-dependent differences in synaptogenic gene expression associated with neuron-tumor connectivity and subsequent invasiveness. Importantly, radiotherapy enhanced neuron-tumor connectivity by increased neuronal activity. In turn, simultaneous neuronal activity inhibition and radiotherapy showed increased therapeutic effects, indicative of a role for neuron-to-glioma synapses in contributing to therapeutic resistance. Lastly, rabies-mediated genetic ablation of tumor-connected neurons halted glioblastoma progression, offering a viral strategy to tackle glioblastoma. Together, this study provides a framework to comprehensively characterize neuron-tumor networks and target glioblastoma.

Link to Publication

Tetzlaff SK, Reyhan E, Layer N, Bengtson CP, Heuer A, Schroers J, Faymonville AJ, Langeroudi AP, Drewa N, Keifert E, Wagner J, Soyka SJ, Schubert MC, Sivapalan N, Pramatarov RL, Buchert V, Wageringel T, Grabis E, Wißmann N, Alhalabi OT, Botz M, Bojcevski J, Campos J, Boztepe B, Scheck JG, Conic SH, Puschhof MC, Villa G, Drexler R, Zghaibeh Y, Hausmann F, Hänzelmann S, Karreman MA *, Kurz FT, Schröter M, Thier M, Suwala AK, Forsberg-Nilsson K, Acuna C, Saez-Rodriguez J, Abdollahi A*, Sahm F*, Breckwoldt MO*, Suchorska B, Ricklefs FL, Heiland DH, Venkataramani V.* Characterizing and targeting glioblastoma neuron-tumor networks with retrograde tracing. Cell. 2025 Jan 23;188(2):390-411.e36. doi: 10.1016/j.cell.2024.11.002. Epub 2024 Dec 6. PMID: 39644898. *UNITE Principle Investigators

 

Research findings related to UNITE work package A01

Diffuse gliomas, particularly glioblastomas, are incurable brain tumours. They are characterized by networks of interconnected brain tumour cells that communicate via Ca²⁺ transients. However, the networks’ architecture and communication strategy and how these influence tumour biology remain unknown. Here we describe how glioblastoma cell networks include a small, plastic population of highly active glioblastoma cells that display rhythmic Ca²⁺ oscillations and are particularly connected to others. Their autonomous periodic Ca²⁺ transients preceded Ca²⁺ transients of other network-connected cells, activating the frequency-dependent MAPK and NF-κB pathways. Mathematical network analysis revealed that glioblastoma network topology follows scale-free and small-world properties, with periodic tumour cells frequently located in network hubs. This network design enabled resistance against random damage but was vulnerable to losing its key hubs. Targeting of autonomous rhythmic activity by selective physical ablation of periodic tumour cells or by genetic or pharmacological interference with the potassium channel KCa3.1 (also known as IK1, SK4 or KCNN4) strongly compromised global network communication. This led to a marked reduction of tumour cell viability within the entire network, reduced tumour growth in mice and extended animal survival. The dependency of glioblastoma networks on periodic Ca²⁺ activity generates a vulnerability that can be exploited for the development of novel therapies, such as with KCa3.1-inhibiting drugs.

LINK TO PUBLICATION

Hausmann D, Hoffmann DC, Venkataramani V*, Jung E, Horschitz S, Tetzlaff SK, Jabali A, Hai L, Kessler T*, Azorín DD, Weil S*, Kourtesakis A, Sievers P, Habel A, Breckwoldt MO*, Karreman M*, Ratliff M*, Messmer JM, Yang Y, Reyhan E, Wendler S, Loeb C, Mayer C, Figarella K, Osswald M, Solecki G, Sahm F*, Garaschuk O, Kuner T, Koch P, Schlesner M*, Wick W*, Winkler F*. Autonomous rhythmic activity in glioma networks drives brain tumor growth. Nature. 2023 Jan 613 7942 179 186. *UNITE Principle Investigators