The WNT/β-catenin pathway is one of the most intensively studied signaling networks in liver cancer biology. Under basal conditions, cytoplasmic β-catenin is held in check by a destruction complex containing APC, Axin, and GSK-3β, which tags the protein for phosphorylation and degradation. When WNT ligands engage their receptors, this process is inhibited, allowing β-catenin to accumulate and translocate to the nucleus, where it partners with TCF/LEF transcription factors to drive the expression of target genes controlling proliferation, differentiation, migration, and survival. Dysregulation of this pathway is a well-established molecular feature of hepatocellular carcinoma, and because it integrates signals governing cell fate, alterations in its activity may represent an important molecular interface between metabolic stress and cancer-associated phenotypes in the liver.

Non-alcoholic fatty liver disease, recently redefined as metabolic dysfunction-associated steatotic liver disease, is the most prevalent chronic liver disease worldwide and carries an increased risk of hepatocellular carcinoma. Disease progression is accompanied by excessive lipid accumulation, oxidative stress, chronic inflammation, mitochondrial dysfunction, and metabolic disturbances that can impair hepatic homeostasis. Lipid overload promotes the production of pro-inflammatory cytokines and reactive oxygen species, contributing to lipid peroxidation that can damage cellular macromolecules and membrane integrity. Persistent oxidative and inflammatory stress may also contribute to DNA damage and genomic instability, providing a mechanistic bridge between metabolic injury and altered cellular signaling. Defining how specific fatty acids alter cancer-relevant signaling pathways may therefore illuminate the molecular connection between metabolic liver disease and hepatocellular carcinoma.

To establish a reproducible lipid-loading model, the researchers first used the MTT assay to determine suitable exposure conditions. Palmitate reduced HepG2 cell viability in a concentration-dependent manner, with estimated IC50 values of approximately 0.8 millimolar after 24 hours and 0.7 millimolar after 48 hours. Oleate was somewhat better tolerated, with IC50 values of approximately 1.0 and 0.9 millimolar at the same time points. Because no significant difference emerged between the 24- and 48-hour values, the shorter exposure was selected for all subsequent experiments. The IC50 concentrations were treated as standardized, experimentally defined exposure levels associated with a measurable cellular response rather than as representations of physiological fatty acid concentrations in vivo.

Combining the two fatty acids proved more challenging than combining their individual tolerances would suggest. When the IC50 concentrations of palmitate and oleate were simply added together, metabolic viability collapsed to roughly 20 percent of control levels, leaving too few viable cells for molecular analysis. The team therefore evaluated lower combinations and settled on 0.4 millimolar palmitate plus 0.8 millimolar oleate, which maintained approximately 50 percent viability while still delivering a robust cellular response. Oil Red O staining confirmed that all treatments significantly increased intracellular lipid droplet accumulation, with the combined treatment producing the highest lipid content of all, indicating a stronger steatotic effect than either fatty acid alone. Lipid droplet accumulation rose progressively with increasing combined concentrations, and an inverse relationship was observed between cell viability and intracellular lipid deposition.

The transcriptional analysis revealed a strikingly asymmetric molecular landscape. Palmitate produced a coordinated activation of canonical WNT/β-catenin signaling components, significantly upregulating WNT expression by 1.53-fold, β-catenin transcript by 3.60-fold, TCF by 1.63-fold, and Axin2, a canonical downstream target gene, by 3.12-fold. In contrast, oleate produced a qualitatively different response, strongly inducing LEF expression by 5.79-fold, the highest transcriptional response among all examined genes, and elevating GSK-3β transcript by 2.27-fold, without significantly altering WNT or TCF expression. Both individual fatty acids suppressed Axin1 transcript levels by approximately 89 percent relative to control, a theoretically significant finding because Axin1 serves as an important scaffold of the β-catenin destruction complex.

Protein-level measurements added crucial nuance to the transcriptional picture. Palmitate significantly increased WNT-1 protein expression by 1.30-fold and β-catenin protein by 1.19-fold, consistent with the corresponding mRNA changes. Oleate and the combined treatment also significantly elevated β-catenin transcript levels, by 2.87-fold and 2.88-fold respectively, but neither produced a corresponding increase in β-catenin protein abundance, which remained comparable to or slightly lower than control levels. Palmitate also significantly elevated Glypican-3 protein expression by 1.35-fold, whereas oleate reduced GPC3 protein levels, although not significantly. These findings demonstrate that palmitate promotes WNT and β-catenin expression at both transcriptional and protein levels, whereas oleate partially attenuates this response despite producing a common phenotype of intracellular lipid accumulation.

The authors interpret these results as evidence that palmitate generates a molecular environment more compatible with enhanced canonical WNT/β-catenin signaling, whereas oleate does not produce the same coordinated pattern. Mechanistically, the simultaneous suppression of Axin1 and induction of Axin2 in palmitate-treated cells is compatible with a shift toward enhanced pathway signaling, because reduced Axin1 may favor β-catenin stabilization while increased Axin2 may reflect activation of a downstream transcriptional response and an accompanying negative-feedback mechanism. The oleate-associated increase in β-catenin transcript without corresponding protein accumulation suggests that transcriptional regulation alone is insufficient to infer sustained canonical WNT activity, and that posttranscriptional and posttranslational mechanisms may contribute to the dissociation between mRNA and protein abundance. The pronounced induction of LEF by oleate should not be interpreted as direct evidence of canonical WNT activation, because TCF and LEF can participate in overlapping as well as context-dependent transcriptional programs.

The combined palmitate/oleate treatment generally produced intermediate molecular responses, attenuating several of the effects induced by each fatty acid alone while maintaining significant activation of selected pathway components. However, the authors caution that because the palmitate concentration differed between the palmitate-alone and combined-treatment conditions, these differences cannot be interpreted as direct evidence of an oleate-mediated protective or antagonistic effect. Rather, they indicate that combined fatty acid exposure produced a molecular response distinct from that observed with palmitate alone. This distinction may be particularly relevant in metabolic liver disease, where hepatocytes are exposed to mixtures of fatty acids rather than to individual lipid species, and where the balance between pathway-promoting and pathway-restraining signals may depend on fatty acid composition.

Several limitations frame the conclusions. The study was performed exclusively in HepG2 cells, a hepatocellular carcinoma-derived model with a transformed phenotype and potentially altered WNT/β-catenin regulation, so the findings cannot be directly extrapolated to normal hepatocytes or to the early stages of metabolic dysfunction-associated steatotic liver disease. Functional WNT/β-catenin activation was not directly assessed through β-catenin nuclear localization, active non-phosphorylated β-catenin measurement, or β-catenin-dependent transcriptional assays, and GSK-3β phosphorylation status and enzymatic activity were not evaluated. Lipidomic and detailed metabolic analyses were not performed, so specific intracellular lipid species, oxidative stress responses, endoplasmic reticulum stress, mitochondrial function, and inflammatory mediators remain unexplored. The MTT assay provides an indirect assessment of metabolic activity and cannot independently distinguish changes in metabolic activity from alterations in cell number or specific cell death mechanisms. Future studies incorporating functional assays, primary or non-transformed hepatocyte models, and appropriate in vivo approaches will be required to validate these findings and clarify the specific contribution and interaction of these fatty acids.

Subject of Research: Fatty acid composition and WNT/β-catenin signaling in lipid-loaded HepG2 cells

Article Title: Differential Modulation of WNT/β‐Catenin Pathway‐Associated Molecular Responses by Palmitate and Oleate in Lipid‐Loaded HepG2 Cells

Article References: Al‐Haeri, M., Mohammadi, Y., Pashaei‐Asl, R., & Bahreini, E. (2026). Differential Modulation of WNT /β‐Catenin Pathway‐Associated Molecular Responses by Palmitate and Oleate in Lipid‐Loaded HepG2 Cells. Cancer Reports, 9(10), Article e70703. https://doi.org/10.1002/cnr2.70703

Image Credits: AI Generated

DOI: 10.1002/cnr2.70703

Keywords: Differential, Modulation, Catenin, Pathway, Associated, Molecular, Responses, Palmitate, Oleate, Lipid, Loaded, HepG2

The research, led by Thoria Donia and Mohamed Hessien along with colleagues at Tanta University and collaborating Egyptian institutes, focused on two cell lines that loom large in cancer biology. HepG2 cells, derived from a human hepatocellular carcinoma, represent the most common form of liver cancer and a leading cause of cancer death worldwide. MDA-MB-231 cells, meanwhile, are a notoriously aggressive model of triple-negative breast cancer, the subtype that resists hormone therapy and targeted drugs alike. The team measured how much chlorpromazine was needed to kill half of the cells in each culture, a standard benchmark known as the IC50. When mdivi-1 was added alongside the antipsychotic, that lethal dose dropped in both cell lines, with the liver cancer cells proving noticeably more responsive than their breast cancer counterparts.

That synergy is not accidental, and the study’s technical work explains why it happens. Mdivi-1 was originally identified in 2008 as a small molecule that blocks dynamin-related protein 1, or Drp1, the molecular engine that pinches mitochondria in two during cell division of these organelles. Cancer cells are famously dependent on finely tuned mitochondrial dynamics, the constant cycling of fusion and fission that keeps their powerhouses distributed, their metabolism flexible, and their survival machinery primed. By jamming the fission machinery, mdivi-1 throws that balance into disarray. Chlorpromazine, for its part, has long been known to disrupt clathrin-mediated endocytosis, the cellular trafficking route that tumors exploit for growth signaling, and earlier studies have shown it can trigger cell cycle arrest and autophagy in cancers ranging from glioblastoma to colorectal tumors.

To probe what the combination was actually doing inside the cells, the researchers deployed a battery of assays that read out the hallmarks of dying and migrating cancer cells. Annexin V and propidium iodide staining, which flags the flipping of membrane phospholipids that marks early apoptosis, revealed a surge in programmed cell death under the dual treatment. Acridine orange and ethidium bromide, together with DAPI staining, exposed the nuclear signature of apoptosis: chromatin condensing into dense, fragmented clumps as the genome was dismantled. The combination also compromised cell membrane integrity, a sign that the cells were losing the structural coherence needed to survive. In clonogenic assays, which test whether single cells can found new colonies over days to weeks, the treated cultures produced far fewer colonies, indicating that the damage was not merely a transient shock but a lasting blow to reproductive capacity.

Migration, the behavior that lets tumors seed metastases throughout the body, was similarly throttled. In wound-healing assays, where a scratch is made across a confluent cell layer and the researchers watch how quickly cells crawl in to close the gap, the combination-treated cells moved sluggishly compared with controls. Behind that physical slowdown lay a molecular shift in epithelial-mesenchymal transition, the developmental program that cancer cells hijack to become mobile and invasive. The team found that the dual treatment downregulated the expression of vimentin and DDR2, two mesenchymal markers that signal a cell’s conversion into the migratory, invasive state. Suppressing this program is a major therapeutic goal in oncology, because mesenchymal tumor cells are typically the ones that break away, circulate, and establish deadly secondary tumors.

The mitochondrial story proved to be the most intricate thread of the study. On its own, mdivi-1 upregulated the expression of the fusion genes MFN1, MFN2, and OPA1, which encode the proteins that merge mitochondria and preserve their functional network. But when chlorpromazine entered the picture, the picture changed: the combined treatment dysregulated both the fusion and the fission gene sets, throwing the entire dynamical system out of balance. This matters because tumor cells rely on a specific rhythm of mitochondrial remodeling to support their abnormal metabolism and to evade apoptosis. Disrupting both sides of the fusion-fission equilibrium at once appears to deprive the cells of the flexibility they need to adapt, compounding the stress imposed by chlorpromazine itself.

Oxidative stress emerged as the engine that converts that mitochondrial chaos into cell death. Using 2′,7′-dichlorodihydrofluorescein diacetate staining, a fluorescent probe that lights up in the presence of reactive oxygen species, the researchers documented an overproduction of cellular ROS in the treated cells. At the same time, the cells’ antioxidant capacity was depleted, and the expression of Nrf2, the master transcription factor that orchestrates the cellular antioxidant response, was downregulated. Nrf2 is a double-edged sword in cancer: many tumors crank it up to neutralize the oxidative byproducts of their runaway metabolism and to resist chemotherapy. By suppressing Nrf2 while simultaneously flooding the cells with ROS, the drug combination stripped cancer cells of both the insult and the defense, leaving them with no route back to equilibrium except apoptosis.

The broader context makes the result more than a laboratory curiosity. Chlorpromazine belongs to a growing list of central nervous system drugs being reexamined as anticancer agents, a strategy that appeals to researchers because these compounds have decades of clinical safety data, known pharmacokinetics, and low manufacturing costs. Recent studies have shown phenothiazines can suppress proliferation in leukemic cells while sparing normal lymphocytes, overcome temozolomide resistance in glioblastoma by interfering with DNA repair pathways, and suppress the YAP signaling axis that drives stemness and drug resistance in breast cancer. Chlorpromazine has also been shown to induce G2/M cell cycle arrest in colorectal and oral cancer cells. Meanwhile, mdivi-1 has independently attracted attention for sensitizing cancer cells to cisplatin and paclitaxel and for suppressing oxidative metabolism in tumors, making the two drugs natural partners in a combination strategy.

Cautions remain before any of this reaches patients. The work was conducted entirely in cell culture, and the gap between a dish of HepG2 cells and a living tumor is wide, encompassing drug delivery, metabolism, immune interactions, and toxicity that no in vitro system can fully model. Chlorpromazine itself carries known liabilities, including hepatotoxicity under inflammatory conditions and extrapyramidal neurological side effects at antipsychotic doses, and the study’s authors and prior literature alike note that safety profiling would be essential. The researchers also point to ongoing efforts to design chlorpromazine derivatives that retain anticancer activity while shedding the neurological side effects, an approach that could yield cleaner candidates. Still, the convergence of a repurposed psychiatric drug with a mitochondrial dynamics inhibitor offers a mechanistically coherent blueprint: attack the trafficking, the power grid, and the antioxidant shield of a tumor cell all at once.

What makes the study resonate beyond its immediate findings is the way it reframes an old drug through a modern lens. Mitochondrial dynamics has moved from a niche organelle-biology topic to a recognized axis of cancer vulnerability, and the Tanta team’s data show that a fission inhibitor can convert a moderately cytotoxic antipsychotic into a substantially more potent anticancer combination. The work was supported by Egypt’s Academy of Scientific Research and Technology and the Science and Technology Development Fund, and the authors report no competing interests. For now, the combination lives in the realm of preclinical promise, but it strengthens the case for clinical exploration of phenothiazine-based regimens, particularly for liver and triple-negative breast cancers where treatment options remain painfully limited. If subsequent animal and human studies bear out the synergy, a drug that has treated the mind since the Eisenhower era may yet earn a second career treating the body.

Subject of Research: Repurposing chlorpromazine combined with the mitochondrial fission inhibitor mdivi-1 as an anticancer strategy in liver and breast cancer cell lines

Article Title: Mdivi-1 augments chlorpromazine’s anticancer effect via modulation of mitochondrial dynamics, hallmarks of cancer-related cellular behavior, and oxidative stress

Article References: Donia, T., Ismail, D. F., Alkafaas, S. S., Adly, E., Tabll, A. A., & Hessien, M. (2026). Mdivi-1 augments chlorpromazine’s anticancer effect via modulation of mitochondrial dynamics, hallmarks of cancer-related cellular behavior, and oxidative stress. Medical Oncology, 43(11), Article 325. https://doi.org/10.1007/s12032-026-03364-w

Image Credits: AI Generated

DOI: 10.1007/s12032-026-03364-w

Keywords: chlorpromazine, mdivi-1, mitochondrial dynamics, drug repurposing, HepG2, MDA-MB-231, apoptosis, oxidative stress, Nrf2, epithelial-mesenchymal transition, mitochondrial fission, Medical Oncology

Organotin compounds have long intrigued medicinal chemists because of their structural versatility and pronounced biological activity, but translating that raw potency into safe therapies has proven difficult. The type and number of organic groups attached to the tin atom strongly influence both cytotoxicity and selectivity, and diorganotin species of the form R2SnX2 generally offer the best balance between killing cancer cells and sparing healthy tissue. Methyl, butyl, and phenyl substituents each tune the Lewis acidity of the central tin and the spatial shape of the complex, which in turn governs how the molecule engages biological targets. The problem, the researchers note, is that the quantitative relationship between structure and activity remains stubbornly hard to predict, which is why systematic comparisons of closely related complexes matter for the field.

To build the new compounds, the team refluxed dimethyltin oxide with a series of substituted cinnamic acids in methanol under a strict 2:1 stoichiometry. The reaction proved remarkably reliable: five distinct complexes, C1 through C5, crystallized in yields of 80 to 86 percent after the filtrate was left to stand at room temperature for several days. The mild conditions and simple operation suggest the route is a general one for constructing this class of tetranuclear tin oxide clusters. Infrared spectroscopy provided the first confirmation that coordination had occurred, with the carboxylate stretching band shifting from the 1700 to 1725 wavenumber range typical of free carboxylic acids down to about 1640, a redshift that signals successful binding to the tin center.

Single-crystal X-ray diffraction revealed that all five complexes share a striking common architecture: a ladder-like Sn4O4 core built from three edge-sharing Sn2O2 rhomboids. The central ring features notably shorter tin-oxygen bonds, between 2.024 and 2.040 angstroms, than the terminal rings, which measure 2.217 to 2.254 angstroms. That contraction reflects the triple-bridging mode of the central oxygen atoms, which link three metal centers each and impose distinctive electronic and steric constraints. Perhaps the most intriguing structural detail is that the terminal, electrophilic tin atoms are capped exclusively by methoxy ligands generated in situ from the methanol solvent, rather than by the carboxylate groups of the cinnamate ligands, a clear example of site selectivity during the self-assembly process.

The two kinds of tin centers in each cluster adopt different geometries. Those in the central ring are five-coordinate with a trigonal bipyramidal arrangement, bound to two bridging oxygens, two methyl groups, and one methoxy ligand. The terminal tin atoms are six-coordinate and distorted octahedral, carrying a chelating carboxylate in addition to the other ligands. Nuclear magnetic resonance data corroborate this picture: the 119Sn spectra of all five complexes show two resonances, near minus 136 and minus 173 parts per million, consistent with coexisting five- and six-coordinate tin centers. Thermogravimetric analysis traced decomposition through loss of methoxy ligands near 100 degrees Celsius followed by pyrolysis of the organic framework, leaving a residue whose mass matched the theoretical yield of tin dioxide.

Before any biological claims could be made, the team needed to know whether the lead complex would survive in the body’s aqueous environment. Ultraviolet-visible spectroscopy showed that C1’s absorption profile is essentially identical in ethanol and in a dilute ethanol-Tris buffer, and the spectrum barely changes across pH values from 3 to 10, a range that spans the acidic microenvironment of tumors to physiological pH. Over 24 hours at pH 7.4, absorbance declined only slightly. Hirshfeld surface analysis of the crystal packing of C1, meanwhile, quantified the intermolecular forces holding the lattice together, finding that hydrogen-hydrogen van der Waals contacts dominate at 63.3 percent, followed by carbon-hydrogen contacts at 15.9 percent and bromine-hydrogen contacts at 8.9 percent.

The mechanistic core of the study concerns how C1 interacts with DNA. Ultraviolet titration showed the complex’s 300-nanometer absorption band shifting about 5 nanometers to the red and diminishing in intensity as DNA concentration rose, behavior characteristic of a planar molecule slipping between stacked base pairs through pi-pi interactions. The calculated binding constant of 1.22 times 10 to the fourth liters per mole falls squarely in the range of established intercalators. A competitive assay using ethidium bromide, a fluorescent dye that fluoresces only when intercalated into DNA, showed dose-dependent quenching as C1 displaced the dye from the helix, with a Stern-Volmer constant of 2.04 times 10 to the fourth. Viscosity measurements sealed the case: DNA viscosity rose sharply with increasing C1 concentration, far more than with the free cinnamic acid ligand or dimethyltin oxide alone, because intercalation lengthens the helix and increases its hydrodynamic volume.

Molecular docking simulations added atomic-level texture to the picture. The optimized binding pose shows the planar cinnamate moiety of C1 slotting coplanar between DNA base pairs, while the tin-bound methyl groups split their duties: some project into the minor groove to make van der Waals contacts, and others point outward to avoid clashing with the phosphate backbone. In cell-based assays against MCF-7 breast cancer, HepG2 liver cancer, and NCI-H460 lung cancer lines, every complex beat cisplatin by a wide margin. Substituent effects were decisive. The 2-bromo derivative C1 led with IC50 values of 3.04, 1.86, and 4.78 micromolar across the three lines, likely because bromine’s electron-withdrawing character and halogen-bonding capacity improve target affinity. The 2,6-dichloro complex C4 followed closely, while the alpha-methyl derivative C5 was weakest, its electron-donating group apparently disrupting favorable interactions.

Flow cytometry revealed how the cells actually die. Using Annexin V-FITC and propidium iodide dual staining, the researchers showed that C1 triggers apoptosis in a dose-dependent fashion in HepG2 cells: 21.26 percent of the population after 48 hours at 1 micromolar, 35.6 percent at 2 micromolar, and 53.6 percent at 4 micromolar. Cell-cycle analysis showed a corresponding concentration-dependent accumulation of cells in the G2/M phase, with depletion of the G0/G1 and S populations. That arrest pattern suggests C1 interferes with mitotic machinery or introduces DNA lesions that activate the cell’s damage response; when the damage cannot be repaired, the intrinsic apoptotic pathway takes over. This coupling of cycle disruption to programmed death offers a coherent mechanistic account of the compound’s antiproliferative power.

The authors position C1 as a high-activity lead for the design of next-generation metallodrugs, emphasizing that its cytotoxicity arises from a synergistic interplay of mechanisms rather than a single target. The work also fills a gap in the organotin literature: while dibutyltin and tricyclohexyltin cinnamates have been systematically studied, dimethyltin analogues remained scarce. The Hunan-based team, funded by the Hunan Provincial Natural Science Foundation, argues that systematically mapping how substituent type and position modulate activity is the surest path from laboratory curiosity to clinical candidate. Considerable distance remains between potent in vitro activity and an approved medicine, and organotin compounds carry well-known toxicity concerns that selectivity data alone cannot resolve. Still, a molecule that is stable across physiological pH, intercalates DNA by a classical mechanism, arrests cancer cells in mitosis, and spares normal liver cells at therapeutic concentrations gives medicinal chemists a concrete scaffold to optimize.

Subject of Research: Synthesis, crystal structures, and anticancer activity of tetranuclear dimethyltin(IV)-cinnamate complexes with ladder-type Sn4O4 clusters

Article Title: Tetranuclear dimethyltin(IV)-cinnamate complexes with a ladder-type Sn4O4 cluster: synthesis, crystal structures, and anticancer activity

Article References: Zhang, Z., Jiang, Z., Tan, Y., Tan, Y., & Jiang, W. (2026). Tetranuclear dimethyltin(IV)-cinnamate complexes with a ladder-type Sn4O4 cluster: synthesis, crystal structures, and anticancer activity. Journal of Saudi Chemical Society, 30(5), Article 75. https://doi.org/10.1007/s44442-026-00129-y

Image Credits: AI Generated

DOI: 10.1007/s44442-026-00129-y

Keywords: organotin, dimethyltin, cinnamic acid, anticancer, Sn4O4 cluster, DNA intercalation, cisplatin, HepG2, apoptosis, cell cycle arrest, crystal structure, metallodrugs