The aberrant activation of the mTOR pathway and its crosstalk with other signaling cascades represent key drivers of hepatocellular carcinoma (HCC) progression. mTOR-mediated ferroptosis suppression has been implicated in HCC resistance to chemotherapy. This study aimed to elucidate the mechanisms underlying mTOR inhibitor resistance and to evaluate the therapeutic potential of multidrug combinations in β-catenin-mutant HCC.

MHCC97H and SNU449 cells were transfected with 4EBP1WT, 4EBP1A4, or HSP90β expression plasmids and then treated with rapamycin to assess their effects on ferroptosis and rapamycin sensitivity. The role of 4EBP1 in regulating ferroptosis was further explored by Western blotting, co-immunoprecipitation, and immunofluorescence. The inhibitory effects of mTOR inhibitors (rapamycin, MLN0128), ERK inhibitors (PD901), and their combination (MLN0128 + PD901) on tumor cells were evaluated. HCC mouse models were generated via hydrodynamic tail vein injection of c-Met/β-cateninΔN90 or c-Met/β-cateninΔN90/4EBP1A4 plasmids to evaluate the therapeutic effects of the four treatment regimens.

Rapamycin more potently inhibited mTOR/RPS6 than mTOR/4EBP1 and concurrently induced ferroptosis. 4EBP1A4 promoted ferroptosis and potentiated rapamycin efficacy. Mechanistically, 4EBP1A4 competitively bound HSP90β, displacing Keap1, thereby increasing Keap1–Nrf2 complex formation and promoting Nrf2 degradation. Furthermore, rapamycin, MLN0128, PD901, and their combination reduced p-4EBP1 levels, induced ferroptosis, and inhibited HCC cell proliferation, thereby suppressing tumor growth, with the combination exhibiting the strongest effect.

4EBP1A4 enhances Nrf2 ubiquitination and degradation via the HSP90β/Keap1 axis, relieving mTOR-mediated ferroptosis suppression and synergistically improving rapamycin efficacy. Additionally, rapamycin, MLN0128, and PD901 suppress HCC progression by inducing ferroptosis, with their combination showing superior potency.

Chronic pelvic pain remains a significant clinical challenge, often refractory to conservative and interventional treatments. Superior hypogastric plexus block is an established technique; however, conventional anterior and posterior approaches may be limited by anatomical variability and potential risks to adjacent structures. Based on these anatomical findings, we propose that a posterior transosseous S1 pedicular approach represents a novel and anatomically robust corridor for accessing the superior hypogastric plexus. We hypothesize that the highly reproducible osseous anatomy of the S1 pedicle, combined with its consistent spatial relationship to the anterior sacral cortex and retroperitoneal compartment, may enable precise and fluoroscopically reproducible instrument guidance toward the plexus. Furthermore, this trajectory may mitigate the anatomical variability and procedural limitations associated with conventional anterior or paravertebral techniques while potentially reducing the risk of inadvertent injury to adjacent visceral, vascular, and neural structures. This concept is based on anatomical reasoning and fluoroscopic observations obtained during cadaveric anatomical orientation, suggesting that a transosseous trajectory through the S1 pedicle toward the anterior sacral cortex may offer improved spatial control and reproducibility compared with soft-tissue-based approaches. The proposed pathway remains conceptual and is not intended for clinical application at this stage. Further cadaveric, imaging-based, and clinical studies are required to evaluate its anatomical validity, safety, and potential clinical relevance.

Liver fibrosis is a central pathological process driving the progression of chronic liver disease, yet effective antifibrotic therapies remain limited. Increasing evidence has identified the mineralocorticoid receptor (MR), a ligand-activated nuclear receptor, as a key regulator of intrahepatic homeostasis and fibrogenesis. MR is expressed across multiple hepatic cell types, including hepatocytes, hepatic stellate cells, macrophages, and liver sinusoidal endothelial cells, where it integrates metabolic, inflammatory, and microvascular signaling. Under pathological conditions, MR activation—mediated by both aldosterone-dependent and ligand-independent mechanisms such as hypoxia and oxidative stress—amplifies core profibrotic pathways, including transforming growth factor-β (TGF-β) signaling, reactive oxygen species (ROS) generation, and nuclear factor-kappa B (NF-κB)–driven inflammation. These molecular mechanisms are executed in a cell-type–specific manner, promoting hepatic stellate cell activation, macrophage-mediated inflammation, hepatocyte metabolic dysfunction, and liver sinusoidal endothelial cell capillarization, thereby forming a self-reinforcing fibrogenic network. Preclinical studies consistently demonstrate that mineralocorticoid receptor antagonists attenuate fibrosis by targeting these interconnected pathways. However, clinical evidence remains limited, with only early-phase trials in metabolic dysfunction-associated steatohepatitis and indirect support from cardiorenal studies. Nonsteroidal mineralocorticoid receptor antagonists, particularly finerenone, exhibit improved receptor selectivity and safety profiles, highlighting their therapeutic potential. Future research should focus on disease-specific patient stratification, validated antifibrotic endpoints, and rigorous safety evaluation to enable effective clinical translation of MR-targeted therapies in liver fibrosis.