> 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-034.md). # BRE 034 ## TTFields, Sorafenib, Autophagy, and ER Stress in Liver Cancer **Clinical Cancer Name:** Hepatocellular Carcinoma\ **Common Cancer Name:** Liver Cancer ## Source Davidi, S., Jacobovitch, S., Shteingauz, A., Martinez-Conde, A., Braten, O., Tempel-Brami, C., Zeevi, E., Frechtel-Gerzi, R., Ene, H., Dor-On, E., Voloshin, T., Tzchori, I., Haber, A., Giladi, M., Kinzel, A., Weinberg, U., & Palti, Y. (2022). *Tumor Treating Fields (TTFields) Concomitant with Sorafenib Inhibit Hepatocellular Carcinoma In Vitro and In Vivo.* *Cancers, 14(12), 2959.* *** ## BRS Score **BRS:** 9.3 / 10\ **STEMD:** S9 / T9 / E10 / M10 / D9\ **External Evidence Level:** High preclinical evidence ## Score Interpretation BRE-034 receives a very strong BRS because it provides both in-vitro and orthotopic in-vivo validation. It supports TTFields activity at 150 kHz in hepatocellular carcinoma and shows that TTFields can amplify sorafenib response through autophagy induction, ER stress escalation, and apoptosis amplification. *** ## Entry Summary BRE-034 asks a major liver cancer question: Can Tumor Treating Fields strengthen sorafenib treatment in liver cancer by pushing cancer cells from stress adaptation into cell death? This study tested TTFields alone and with sorafenib in liver cancer models. In simple language: Liver cancer cells may try to survive stress by activating repair or adaptation pathways. BRE-034 suggests that TTFields, especially when combined with sorafenib, may overload those stress systems and push the cancer cells toward death. *** ## What BREXAtlas Found BREXAtlas identifies this primary mechanism chain: TTFields\ ↓\ Autophagy induction\ ↓\ ER stress escalation\ ↓\ Cleaved PARP increase\ ↓\ Apoptosis\ ↓\ Reduced HCC growth A combination chain is: TTFields\ +\ Sorafenib\ ↓\ Amplified cellular stress\ ↓\ Autophagy overload\ ↓\ ER stress elevation\ ↓\ Apoptotic collapse\ ↓\ Stable disease induction This makes BRE-034 a major liver cancer systems entry because it connects electric-field exposure, drug sensitization, stress biology, and tumor suppression. *** ## Questions This BRE Helps Answer ### What frequency was used for liver cancer? What BREXAtlas found:\ BRE-034 used TTFields at 150 kHz. The study also recorded field intensity differences by cell line: * HepG2: 1.0 V/cm RMS * Huh-7D12: 1.7 V/cm RMS This strengthens the liver cancer frequency map first introduced in BRE-033. ### What is autophagy? Autophagy is a process where cells recycle damaged parts to survive stress. Sometimes autophagy helps a cell survive. But under too much stress, it may become part of the pathway toward cell death. What BREXAtlas found:\ BRE-034 supports an autophagy–apoptosis transition, where TTFields and sorafenib may push liver cancer cells from stress adaptation into apoptotic collapse. ### What is ER stress? ER stress happens when the endoplasmic reticulum, a cell structure involved in protein processing, becomes overwhelmed. What BREXAtlas found:\ BRE-034 links TTFields and sorafenib with ER stress escalation, GRP78 elevation, cleaved PARP increase, and apoptosis. ### Why does sorafenib matter? Sorafenib is a liver cancer drug. What BREXAtlas found:\ BRE-034 supports that TTFields plus sorafenib produced stronger anti-tumor effects than either treatment alone, including reduced tumor volume and tumor weight in vivo. *** ## Study Classification | Category | Classification | | ---------------------------------------- | ---------------------------------------------------------- | | Study Type | Experimental in-vitro + in-vivo TTFields combination study | | Tissue Category | Hepatocellular carcinoma / liver cancer | | Cell Lines / Models | HepG2, Huh-7D12, N1S1 orthotopic rat HCC model | | Frequency | 150 kHz | | Intensity | HepG2: 1.0 V/cm RMS; Huh-7D12: 1.7 V/cm RMS | | Drug Combination | Sorafenib | | Direct TTFields Evidence | Yes | | Direct In-Vivo Evidence | Yes | | Direct Combination Evidence | Yes | | Suitable for Liver Cancer Index | Yes | | Suitable for Frequency Index | Yes | | Suitable for Autophagy / ER Stress Index | Yes | *** ## Cell Lines / Models BRE-034 identified: * HepG2 * Huh-7D12 * N1S1 orthotopic rat HCC model These models make BRE-034 stronger than BRE-033 because BRE-034 includes in-vivo liver tumor validation. *** ## Mechanisms **MEC-004: Combination Therapy Amplification** TTFields plus sorafenib produced stronger anti-tumor effects than either treatment alone. **MEC-031: Mitochondrial / Cellular Electrical Stress** TTFields contributed to cellular stress pathways that reduced HCC growth. **MEC-032: ROS-Electromagnetic Coupling** BRE-034 connects to the broader ROS and stress-response pathway. **MEC-042: Autophagy–Apoptosis Stress Transition** TTFields and combination therapies may induce progressive stress that shifts protective autophagy into apoptotic collapse. **MEC-043: ER-Stress Amplification Signaling** TTFields-induced cellular stress may amplify ER stress pathways, contributing to tumor-cell apoptosis and stable disease induction. **MEC-090: HCC TTFields In-Vivo Validation** BRE-034 supports in-vivo liver cancer suppression under TTFields plus sorafenib conditions. *** ## Discoveries **DISC-013: ROS and Electromagnetic Stress Integration** BRE-034 supports the discovery that electric-field exposure may interact with oxidative and stress-response pathways. **DISC-019: Autophagy–Apoptosis Transition Systems** BREXAtlas identifies this as a major liver cancer discovery: TTFields and sorafenib may push HCC cells from autophagic adaptation into apoptotic collapse. **DISC-021: HCC TTFields Translational Validation** BRE-034 strengthens the liver cancer section by moving beyond in-vitro cell response into in-vivo orthotopic tumor suppression. *** ## Connections to Other BRE Entries ### Connected to BRE-033 BRE-033 showed TTFields at 150 kHz suppressed Hep3B and HepG2 liver cancer cells and amplified sorafenib effects in vitro. BRE-034 strengthens that pathway by adding Huh-7D12, HepG2, and in-vivo orthotopic HCC evidence. ### Connected to BRE-020 BRE-020 described TTFields combination potential with radiation and chemotherapy. BRE-034 provides liver cancer evidence that TTFields can amplify a drug-combination pathway. ### Connected to BRE-024 BRE-024 connected electromagnetic exposure with ROS, mitochondrial stress, and altered cancer-cell viability. BRE-034 extends stress-response logic into liver cancer through autophagy, ER stress, and apoptosis escalation. ### Connected to BRE-021 BRE-021 emphasized frequency optimization. BRE-034 supports 150 kHz as a liver cancer TTFields frequency point. ### Connected to BRE-018 BRE-018 showed treatment amplification through DNA repair vulnerability in lung cancer. BRE-034 shows treatment amplification through stress overload and apoptosis in liver cancer. *** ## Research Gaps Identified **RG-167: HCC Autophagy-Threshold Quantification Gap** More research is needed to determine when autophagy shifts from protective adaptation to apoptotic collapse. **RG-168: ER Stress Normalization Gap** ER stress markers need standardized measurement across HCC models and TTFields protocols. **RG-169: Liver-Specific TTFields Optimization Gap** More work is needed to determine whether 150 kHz is optimal across HCC cell lines and tumor subtypes. **RG-170: Stable Disease Prediction Gap** Future studies should determine which biomarkers predict stable disease under TTFields plus sorafenib. **RG-171: Clinical Translation Gap** Controlled human trials and standardized TTFields delivery protocols are needed before clinical conclusions can be made. *** ## Scientific Caution BRE-034 demonstrates strong preclinical evidence, but translation into clinical HCC treatment requires controlled human trials and standardized TTFields delivery systems. *** ## Why This Entry Matters For researchers, BRE-034 is one of the strongest liver cancer entries because it includes both cell-level and animal-model evidence. For patients and families, the simple idea is this: Electric fields helped slow liver cancer growth in preclinical models, especially when paired with sorafenib. The study suggests cancer cells may be pushed from stress survival into cell death. This is not yet proof of a standard treatment. It is strong preclinical evidence that deserves clinical testing. *** ## Entry Conclusion BRE-034 strengthens the Liver / HCC section of the BREXAtlas Encyclopedia. BRE-033 introduced TTFields plus sorafenib in Hep3B and HepG2 cells. BRE-034 adds HepG2, Huh-7D12, and an orthotopic rat HCC model, while showing autophagy, ER stress, apoptosis escalation, and in-vivo tumor suppression. The central question emerging from this entry is: Can TTFields plus sorafenib push liver cancer cells beyond stress adaptation and into apoptotic collapse? For BREXAtlas, BRE-034 is a cornerstone liver cancer entry because it links frequency, drug sensitization, stress biology, and in-vivo validation. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://www.brexatlas.org/bre-001/bre-034.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.