> For the complete documentation index, see [llms.txt](https://www.brexatlas.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.brexatlas.org/bre-001/bre-042.md).
# BRE 042
## TTFields, Tumor Microtubes, and Glioblastoma Network Disruption
**Clinical Cancer Name:** Glioblastoma
**Common Cancer Name:** Aggressive Brain Cancer
## Source
Schlieper-Scherf, S., Hebach, N., Hausmann, D., Azorín, D. D., Hoffmann, D. C., Horschitz, S., Maier, E., Koch, P., Karreman, M. A., Etminan, N., & Ratliff, M. (2024).
*Disrupting glioblastoma networks with tumor treating fields (TTFields) in in vitro models.*
*Journal of Neuro-Oncology, 170, 139–151.*
***
## BRS Score
* **BRS:** 9.0 / 10
* **STEMD:** S9 / T9 / E9 / M10 / D8
* **External Evidence Level:** High experimental tumor-network biology evidence
## Score Interpretation
BRE-042 receives a strong BRS because it provides experimental evidence that TTFields disrupted glioblastoma tumor microtube networks, reduced intercellular connectivity, reduced calcium transient activity, reduced synchronization, reduced infiltration, and reduced proliferation.
***
## Entry Summary
BRE-042 asks a cancer-neuroscience question:
Can TTFields disrupt the communication networks that help glioblastoma cells coordinate, invade, and survive?
Glioblastoma cells can form connected networks through structures called tumor microtubes.
In simple language:
Some brain cancer cells do not act alone. They connect with each other, communicate, and coordinate activity. BRE-042 suggests TTFields may weaken those cancer-cell networks.
***
## What BREXAtlas Found
BREXAtlas identifies this primary mechanism chain:
TTFields\
↓\
Tumor microtube disruption\
↓\
Reduced intercellular connectivity\
↓\
Reduced network integrity\
↓\
Tumor-network collapse
The calcium chain is:
TTFields\
↓\
Reduced calcium transients\
↓\
Reduced periodic activity\
↓\
Reduced intercellular co-activity\
↓\
Network desynchronization
The invasion chain is:
TTFields\
↓\
Reduced tumor microtube connectivity\
↓\
Reduced infiltration\
↓\
Reduced glioblastoma spread
This makes BRE-042 important because it frames glioblastoma not only as a dividing-cell problem, but also as a connected tumor-network problem.
***
## Questions This BRE Helps Answer
What are tumor microtubes?
Tumor microtubes are long cellular extensions that help glioblastoma cells connect with each other.
What BREXAtlas found:\
BRE-042 supports that TTFields can disrupt tumor microtube architecture and reduce network interconnectivity.
Why does calcium signaling matter?
Calcium signaling helps cells communicate and coordinate activity.
What BREXAtlas found:\
TTFields reduced calcium transient activity, periodic activity, intercellular co-activity, and network synchronization.
Why is this different from earlier TTFields entries?
Earlier entries focused on cell division, DNA repair, immune activation, or drug combinations.
What BREXAtlas found:\
BRE-042 adds a new layer: TTFields may interfere with tumor-cell communication networks.
What models were studied?
What BREXAtlas found:\
BRE-042 used S24, BG5, T269, patient-derived tumoroids, and brain tumor organoids.
***
## Study Classification
| Category | Classification |
| ------------------------------------ | ---------------------------------------------------------------- |
| Study Type | Experimental glioblastoma network biology study |
| Tissue Category | Glioblastoma; cancer neuroscience; tumor network biology |
| Models | S24, BG5, T269, patient-derived tumoroids, brain tumor organoids |
| Exposure System | TTFields |
| Primary Frequency | 200 kHz |
| Comparison Frequency | 50 kHz |
| Direct TTFields Evidence | Yes |
| Direct Calcium-Network Evidence | Yes |
| Suitable for Glioblastoma Index | Yes |
| Suitable for Tumor Network Index | Yes |
| Suitable for Calcium Signaling Index | Yes |
***
## Mechanisms
* **MEC-007: Calcium Signaling**\
TTFields reduced calcium transients and network-level calcium coordination.
* **MEC-027: Voltage-Gated Ion Channel Activation**\
BRE-042 connects to ion-channel and calcium-signaling ontology through network desynchronization, though it does not primarily define a specific channel target.
* **MEC-038: Tumor Microenvironment Bioelectric Regulation**\
TTFields may alter how glioblastoma cells coordinate within their microenvironment.
* **MEC-098: Tumor Microtube Disruption**\
TTFields may disrupt tumor microtube architecture.
* **MEC-099: Network Connectivity Collapse**\
TTFields may reduce intercellular connectivity and weaken tumor-network integrity.
* **MEC-100: Glioblastoma Network Desynchronization**\
TTFields may reduce synchronized calcium activity and coordinated tumor behavior.
***
## Discoveries
* **DISC-017: Bioelectric Tumor Microenvironment Systems**\
BRE-042 strengthens the discovery that tumor behavior may depend on bioelectric and network-level communication.
* **DISC-021: Clinical Systems-Level TTFields Integration**\
BRE-042 expands TTFields systems integration by showing a network-level mechanism in glioblastoma.
* **DISC-027: Tumor-Network Disruption by TTFields**\
BREXAtlas identifies this as a major discovery:\
TTFields may disrupt glioblastoma not only by killing dividing cells, but also by weakening tumor-cell communication networks.
***
## Connections to Other BRE Entries
### Connected to BRE-036
BRE-036 established TTFields as a clinical glioblastoma systems platform.
BRE-042 adds a tumor-network biology mechanism that helps explain another possible layer of glioblastoma response.
### Connected to BRE-031
BRE-031 described bioelectric dysregulation across cancer initiation, progression, tumor microenvironment, extracellular vesicles, and mechanotransduction.
BRE-042 provides glioblastoma-specific experimental evidence for tumor-network bioelectric disruption.
### Connected to BRE-030
BRE-030 connected calcium-channel signaling with breast cancer brain metastasis suppression.
BRE-042 also centers calcium signaling, but in glioblastoma tumor-network synchronization rather than breast cancer metastasis.
### Connected to BRE-014 through BRE-016
BRE-014 through BRE-016 focused on mitotic and cytokinetic disruption.
BRE-042 adds a non-mitotic network-disruption layer.
### Connected to BRE-021
BRE-021 emphasized field optimization and clinical translation.
BRE-042 contributes frequency-relevant glioblastoma evidence using 200 kHz with 50 kHz comparison.
***
## Research Gaps Identified
* **RG-208: Tumor Microtube Mechanism Gap**\
More research is needed to determine exactly how TTFields disrupt tumor microtube architecture.
* **RG-209: Calcium Network Mapping Gap**\
More work is needed to map how TTFields changes calcium signaling across tumor networks.
* **RG-210: Frequency-Specific Network Gap**\
Future studies should clarify why 200 kHz affects glioblastoma networks and how it compares with 50 kHz.
* **RG-211: Organoid-to-Patient Translation Gap**\
Patient-derived tumoroid and organoid findings require clinical validation.
* **RG-212: Network Resistance Gap**\
More research is needed to determine whether glioblastoma networks adapt or reconnect under long-term TTFields exposure.
***
## Scientific Caution
BRE-042 provides experimental tumor-network evidence in in-vitro and organoid-style glioblastoma models. Clinical interpretation requires additional validation in patient systems and long-term treatment contexts.
***
## Why This Entry Matters
For researchers, BRE-042 shows that TTFields may affect glioblastoma as a connected network, not only as individual dividing cells.
For patients and families, the simple idea is this:
Some aggressive brain cancer cells connect and communicate with each other. This study suggests electric-field therapy may weaken those cancer-cell connections.
This is not a standalone cure claim. It is a new way to understand how TTFields may affect glioblastoma behavior.
***
## Entry Conclusion
BRE-042 is a major glioblastoma network-biology entry.
BRE-036 showed clinical TTFields translation in glioblastoma.
BRE-042 adds tumor microtube disruption, calcium signaling collapse, network desynchronization, reduced infiltration, and reduced proliferation.
The central question emerging from this entry is:
Can TTFields weaken glioblastoma by disrupting the networks cancer cells use to communicate, coordinate, and invade?
For BREXAtlas, BRE-042 is essential because it adds cancer neuroscience and tumor-network disruption to the TTFields mechanism map.
---
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