> 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-033.md).
# BRE 033
## TTFields, Sorafenib, ROS, and Apoptosis in Liver Cancer
**Clinical Cancer Name:** Hepatocellular Carcinoma
**Common Cancer Name:** Liver Cancer
## Source
Jang, Y., Lee, W. S., Sai, S., Kim, J. Y., Kim, J.-K., & Kim, E. H. (2022).
*Tumor-treating fields in combination with sorafenib restrain the proliferation of liver cancer in vitro.*
*Oncology Letters, 24*, 338.
## BRS Score
**BRS:** 8.7 / 10\
**STEMD:** S9 / T8 / E8 / M9 / D9\
**External Evidence Level:** Moderate experimental in-vitro evidence
## Score Interpretation
BRE-033 receives a strong BRS because it provides direct in-vitro evidence that TTFields at 150 kHz inhibited hepatocellular carcinoma cell viability, proliferation, colony formation, migration, and invasion. It also shows stronger suppression when TTFields were combined with sorafenib.
## Entry Summary
BRE-033 asks a liver cancer question:
Can Tumor Treating Fields weaken liver cancer cells and make sorafenib more effective?
This study tested TTFields in hepatocellular carcinoma models, specifically Hep3B and HepG2.
In simple language:
Liver cancer cells were exposed to electric fields. The fields reduced cancer-cell growth and movement. When combined with sorafenib, a liver cancer drug, the effects were stronger.
## What BREXAtlas Found
BREXAtlas identifies this primary mechanism chain:
TTFields at 150 kHz\
↓\
ROS generation\
↓\
Caspase-3 activation\
↓\
PARP cleavage\
↓\
Apoptosis\
↓\
Reduced HCC proliferation and viability
A combination chain is:
TTFields\
+\
Sorafenib\
↓\
Amplified ROS generation\
↓\
Increased apoptosis\
↓\
Reduced colony formation\
↓\
Reduced migration / invasion\
↓\
Enhanced HCC suppression
This makes BRE-033 important because it expands TTFields evidence into liver cancer and links electric-field exposure with oxidative stress, apoptosis, and drug sensitization.
## Questions This BRE Helps Answer
What is hepatocellular carcinoma?
Hepatocellular carcinoma, or HCC, is the most common form of primary liver cancer.
What BREXAtlas found:\
BRE-033 provides in-vitro HCC evidence using Hep3B and HepG2 liver cancer cell models.
What frequency was used?
What BREXAtlas found:\
The study used TTFields at 150 kHz with an intensity of 1.0 V/cm. Sorafenib was used at 5 µM.
This matters because BREXAtlas tracks frequency specificity across cancer types.
What is sorafenib?
Sorafenib is a cancer drug used in liver cancer treatment research and care.
What BREXAtlas found:\
BRE-033 supports that TTFields combined with sorafenib produced stronger anti-tumor effects than either treatment alone in Hep3B and HepG2 cell models.
Why do ROS and apoptosis matter?
ROS are stress molecules that can damage cells when they build up.
Apoptosis is programmed cell death.
What BREXAtlas found:\
BRE-033 links TTFields with ROS generation, caspase-3 activation, PARP cleavage, and apoptosis in liver cancer cells.
## Study Classification
| Category | Classification |
| -------------------------------------- | ------------------------------------------------------------ |
| Study Type | Experimental in-vitro TTFields + sorafenib combination study |
| Tissue Category | Liver cancer / hepatocellular carcinoma |
| Common Cancer Name | Liver cancer |
| Cell Lines | Hep3B, HepG2 |
| Frequency | 150 kHz |
| Intensity | 1.0 V/cm |
| Drug Combination | Sorafenib, 5 µM |
| Direct TTFields Evidence | Yes |
| Direct Combination Evidence | Yes |
| Suitable for Liver Cancer Index | Yes |
| Suitable for Frequency Index | Yes |
| Suitable for Combination Therapy Index | Yes |
## Cell Lines / Models
BRE-033 identified:
* Hep3B
* HepG2
These are foundational liver cancer cell lines for the Liver / HCC section of the encyclopedia.
## Mechanisms
**MEC-002: Frequency Specificity**
BRE-033 contributes a liver cancer TTFields frequency point: 150 kHz.
**MEC-004: Combination Therapy Amplification**
TTFields plus sorafenib produced stronger anti-tumor effects than either treatment alone.
**MEC-031: Mitochondrial Electrical Stress**
ROS generation and apoptosis suggest cellular stress pathways may contribute to reduced viability.
**MEC-032: ROS-Electromagnetic Coupling**
TTFields increased ROS generation in HCC cells.
**MEC-088: Sorafenib Sensitization in HCC**
TTFields may amplify sorafenib-induced suppression in liver cancer models.
**MEC-089: HCC Migration and Invasion Suppression**
TTFields reduced migration and invasion, with MMP9 downregulation identified as a related pathway.
## Discoveries
**DISC-013: ROS and Electromagnetic Stress Integration**
BRE-033 supports the discovery that electromagnetic or electric-field exposure can interact with oxidative stress and apoptosis pathways.
**DISC-019: Liver Cancer TTFields Transferability**
BREXAtlas identifies this as a major Batch 4 discovery:
TTFields mechanisms previously observed in other cancers may transfer into liver cancer models, but liver-specific optimization remains necessary.
**DISC-020: Sorafenib Combination Amplification in HCC**
BRE-033 supports the discovery that TTFields may strengthen sorafenib-related suppression in liver cancer models.
## Connections to Other BRE Entries
**Connected to BRE-018**
BRE-018 showed TTFields could increase radiation vulnerability in lung cancer by reducing DNA repair capacity.
BRE-033 shows another combination pathway: TTFields plus sorafenib in liver cancer.
**Connected to BRE-020**
BRE-020 synthesized TTFields combination potential with radiation and chemotherapy.
BRE-033 provides liver cancer evidence supporting combination-treatment amplification.
**Connected to BRE-024**
BRE-024 connected electromagnetic exposure with ROS generation and mitochondrial stress in breast cancer cells.
BRE-033 extends ROS-electromagnetic coupling into liver cancer TTFields response.
**Connected to BRE-032**
BRE-032 showed pattern-specific EMF response through calcium-channel signaling.
BRE-033 uses TTFields rather than calcium-channel targeting, but both support the broader concept that cancer cells may have parameter-specific electromagnetic vulnerabilities.
**Connected to BRE-021**
BRE-021 emphasized frequency optimization and clinical translation.
BRE-033 contributes a specific liver cancer frequency point: 150 kHz.
## Research Gaps Identified
**RG-162: Liver-Specific TTFields Optimization Gap**
More work is needed to determine optimal frequency, intensity, duration, and waveform parameters for liver cancer.
**RG-163: HCC Frequency Normalization Gap**
Future studies should compare whether 150 kHz is optimal for Hep3B, HepG2, and other HCC cell lines.
**RG-164: Sorafenib Resistance Reversal Gap**
More research is needed to determine whether TTFields can overcome sorafenib resistance pathways.
**RG-165: HCC ROS Threshold Quantification Gap**
More studies are needed to define how much ROS increase is needed for cancer-cell suppression without harming normal liver cells.
**RG-166: In-Vivo Translation Gap**
This study is in vitro and requires in-vivo and patient-level validation.
## Scientific Caution
BRE-033 supports TTFields and sorafenib combination effects in Hep3B and HepG2 in-vitro systems. It should not be treated as clinical validation without in-vivo and patient-level replication.
## Why This Entry Matters
For researchers, BRE-033 is important because it brings liver cancer into the TTFields encyclopedia with clear frequency, cell-line, and combination-treatment data.
For patients and families, the simple idea is this:
Electric fields slowed liver cancer cells in the lab, and the effect was stronger when combined with sorafenib.
This does not prove a treatment for patients yet. It shows a research path worth testing further.
## Entry Conclusion
BRE-033 expands BREXAtlas into liver cancer.
Earlier entries established TTFields mechanisms across mitosis, DNA repair, ROS, and combination therapy.
BRE-033 shows that liver cancer models Hep3B and HepG2 respond to TTFields at 150 kHz and that sorafenib may amplify the effect.
The central question emerging from this entry is:
Can TTFields be optimized for liver cancer and used to strengthen sorafenib-based treatment strategies?
For BREXAtlas, BRE-033 is a foundation entry for the Liver / HCC section and the future liver cancer frequency-response map.
---
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