Plant Compound p-Coumaric Acid Fights Liver Cancer by Boosting ROS

Hepatocellular carcinoma, the most common form of liver cancer, remains one of the most lethal malignancies worldwide, and clinicians have long sought new strategies that exploit vulnerabilities unique to cancer cells. A research team at Nanchang University in China now reports that p-coumaric acid, a naturally occurring phenolic compound abundant in fruits, vegetables, and grains, shows striking anti-cancer activity against liver cancer cells by deliberately pushing them into a state of catastrophic oxidative stress. The study, published in Medical Oncology, is the first to document this effect for the compound and to map the molecular machinery behind it, offering a fresh example of how dietary phytochemicals might be repurposed as candidates for cancer therapy.

The paradox at the heart of the work is one that has fascinated cancer biologists for years: although reactive oxygen species, or ROS, are often painted as molecular vandals that damage DNA and drive tumor formation, cancer cells actually live dangerously close to the edge of oxidative tolerance. Having adapted to a certain baseline of ROS, they depend heavily on antioxidant defenses to keep levels from tipping into lethal territory. Pushing ROS past that threshold has therefore emerged as a promising therapeutic concept, and the Nanchang team set out to test whether p-coumaric acid could serve as the tipping force.

In a battery of in vitro experiments, the researchers exposed hepatocellular carcinoma cells to the compound and measured its effects on growth, proliferation, migration, and survival. The results were unambiguous. p-Coumaric acid significantly inhibited the growth and proliferation of the cancer cells, impeded their ability to migrate in wound healing and Transwell assays, and triggered the characteristic physical hallmarks of programmed cell death, including cell shrinkage. Flow cytometry confirmed that the treated cells were dying by apoptosis, and further analysis showed that the compound suppressed the levels of anti-apoptotic and pro-proliferative proteins that liver cancer cells rely on to survive.

The mechanistic story, however, is where the study becomes technically compelling. Using measurements of mitochondrial function, the team found that p-coumaric acid reduced the mitochondrial membrane potential and cut ATP production in the cancer cells. This energetic collapse is significant because mitochondria are both the power plants of the cell and a major source of ROS: when the electron transport chain is disrupted, electrons leak and combine with oxygen to form superoxide and related reactive species. By destabilizing mitochondrial function, the compound effectively opened the floodgates for endogenous ROS accumulation, drowning the cancer cells in their own reactive byproducts.

The researchers then turned their attention to the cell’s principal antioxidant safety valve, the Nrf2 signaling pathway. Nrf2, or nuclear factor erythroid 2-related factor 2, is a transcription factor that, when activated, switches on a broad program of antioxidant and detoxification genes, including heme oxygenase-1, or HO-1. In many tumors, Nrf2 is constitutively active, granting cancer cells remarkable resistance to oxidative stress and to chemotherapy. The team found that p-coumaric acid inhibits this pathway in liver cancer cells, removing a critical layer of protection and allowing ROS levels to climb even higher. The compound thus attacks from two directions at once: it boosts ROS production through mitochondrial dysfunction while simultaneously dismantling the defenses that would normally neutralize it.

To confirm that the Nrf2 arm of the mechanism was genuinely responsible for part of the effect, the researchers used hemin, an agonist of the antioxidant enzyme HO-1. When hemin was applied, it counteracted the inhibitory effect of p-coumaric acid on the viability of the cancer cells, demonstrating that re-engaging the antioxidant machinery could rescue the tumor cells from the oxidative assault. This pharmacological rescue experiment strengthens the causal chain linking Nrf2 inhibition, ROS accumulation, and cell death, rather than leaving the pathway as a mere correlation observed in treated cells.

The in vivo evidence proved equally persuasive. Using a subcutaneous xenograft mouse model of hepatocellular carcinoma, the team showed that p-coumaric acid suppressed tumor growth in living animals. Crucially, when the mice were also treated with N-acetylcysteine, a well-established ROS scavenger, the anti-cancer effects of the compound were reversed. This is the kind of result that carries real weight in redox biology: if mopping up reactive oxygen species abolishes the therapeutic effect, then ROS accumulation is not a side effect but the engine of the compound’s anti-tumor activity. The N-acetylcysteine experiment therefore serves as the linchpin connecting the cellular mechanism to the whole-animal outcome.

The findings also sit within a growing body of literature on p-coumaric acid, a compound already known for anti-inflammatory, antioxidant, and protective effects in contexts ranging from diabetic kidney disease to lung inflammation. Earlier work had hinted at anti-cancer potential, including studies showing apoptotic effects in colon cancer cells and cytotoxicity in neuroblastoma cells through ROS-mediated mitochondrial dysfunction, as well as nanoparticle delivery strategies for breast cancer therapy. What distinguishes the new study is its systematic dissection of the compound’s action in hepatocellular carcinoma specifically, a cancer for which treatment options remain limited and recurrence rates remain high, and its dual demonstration of mitochondrial and Nrf2-targeted mechanisms backed by in vivo validation.

The broader implications are twofold. First, the work reinforces the emerging view that redox homeostasis is a pivotal regulator of liver cancer progression and that deliberately disrupting it is a viable therapeutic strategy, one shared by other natural products and by synthetic agents designed to induce oxidative stress in tumors. Second, it suggests that p-coumaric acid, a cheap and widely available dietary molecule with a favorable safety profile in other contexts, could be developed further as a lead compound, whether administered directly, formulated into targeted delivery systems, or combined with existing therapies to sensitize tumors. The authors, led by Jiahao Zheng and corresponding author Yange Liu of the School of Basic Medical Sciences at Nanchang University, caution that the findings come from cell culture and mouse models, and that translating them into clinical practice will require pharmacokinetic studies, dosing optimization, and eventually human trials. Still, the study adds a compelling entry to the pharmacopeia of plant-derived molecules under investigation for cancer therapy, and it underscores a lesson that modern oncology keeps relearning: sometimes the most effective way to kill a cancer cell is not to poison it directly, but to strip away its defenses and let the chemistry it cannot escape do the rest.

Subject of Research: The anti-cancer effects and ROS-based mechanism of p-coumaric acid in hepatocellular carcinoma

Article Title: p-Coumaric acid inhibits hepatocellular carcinoma through promoting ROS accumulation

Article References: Zheng, J., Zhang, Q., Wang, L., Yuan, M., Wang, Y., Wei, X., Lian, H., Liu, X., & Liu, Y. (2026). p-Coumaric acid inhibits hepatocellular carcinoma through promoting ROS accumulation. Medical Oncology, 43(10), Article 279. https://doi.org/10.1007/s12032-026-03367-7

Image Credits: AI Generated

DOI: 10.1007/s12032-026-03367-7

Keywords: p-coumaric acid, hepatocellular carcinoma, reactive oxygen species, Nrf2 pathway, mitochondrial dysfunction, apoptosis, liver cancer, oxidative stress, natural compounds, HO-1, N-acetylcysteine, cancer therapy