Exploration of Targeted Anti-tumor Therapy

Table 3. Current clinical studies using liquid biopsy in glioblastomas

Year	Study	Tumor	Name/Method	Outcome measures
2020–2024	NCT04201873 [72] Interventional phase I	40 Recurrent GBM	RNA-seq and nanoString IO360	Other outcome/measures: gene expression signature from peripheral blood before/after treatment
2020–2025	NCT04274283 [73] Observational	1,000 Glioma II–IV	Tessa Jowell BRAIN MATRIX, whole genome and epigenomic classification	Matching tumor and blood, but not CSF, for targetable mutations
2021–2024	NCT04931732 [74] CircTeloDIAG Observational	150 MRI suspected: glioma II–IV, incl. GBM	CicTeloDIAG 3 oncogenic pathways: IDH TERT ATRX	Validate liquid biopsy for glioma II–IV; blood ctDNA (also from CTCs) for diagnosis and monitoring of relapse
2021–2025	NCT05099068 [75] Interventional	500 Advanced/metastatic tumors, GBM, CLL	PLANET sequential liquid biopsy, WES, RNA-seq	Monitoring changes in the genetic profile of GBM after chemotherapy
2022	Pagès et al. [76]	258 CNS tumors, incl. HGG (no adult GMB)	ULP-WGS	ctDNA detection: CSF > blood, not in urine. Liquid biopsy is useful for high-grade tumors
2022	NCT04539431 [77] Observational	220 Glioma	SensiScreen glioma	Validation of cheaper, more sensitive PCR-platform for liquid biopsy (blood and CSF), comparison with tissue
2022–2023	NCT05383872 [78] Diagnostic	57 GBM	Microbubble resonator (Exablate Model 4000)	BBBD or liquid biopsy expected to increase cfDNA
2022–2024	NCT05281731 [87] Interventional	20 GBM	Sonobiopsy device testing, blood ctDNA, deep sequencing	Matching mutations post-sonobiopsy and tumor tissue
2022	NCT05133154 [79] Exploratory	50 Participants, DLGG (30 low-grade, 10 high-grade glioma, 10 controls)	Liquid biopsy in low-grade glioma, CTC, TEP	Search for CTCs (> 0), TEP in blood, evaluation of blood-based biomarkers (IDH, 1p19q, ATRX) for diagnosis and monitoring
2022–2023	NCT05536024 [80] Observational	500 Glioma	Liquid biopsy, deep learning MRI	Prediction of glioma grading and molecular subtype

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IO360: Immuno-Oncology 360°; HGG: high-grade glioma; ULP-WGS: ultra-low-pass whole-genome sequencing

Declarations

Acknowledgments

We gratefully acknowledge the introduction into the field of brain tumor research by Otmar D. Wiestler and the late Paul Kleihues, as well as discussions with Irving L. Weissman and Eugene C. Butcher on immune and tumor cell migration and metastasis, and Catherine Alix-Panabières on liquid biopsy.

Author contributions

RHE: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. MS: Conceptualization, Investigation, Writing—review & editing. Both of the authors read and approved the submitted version.

Conflicts of interest

The authors declare that they have no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent to publication

Not applicable.

Availability of data and materials

Not applicable.

Funding

Not applicable.

Copyright

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