Abstract Breast cancer is the most frequently diagnosed cancer in women with an estimated 316,950 new cases and 42,170 deaths in the United States in 2025. Approximately 15% of all breast cancers are diagnosed as a malignant subtype known as triple negative breast cancer (TNBC; ER-/PR-/HER2-), which render hormonal therapies ineffective. Combination chemotherapy is the standard-of-care in TNBC patients, but many experience chemoresistance, which accounts for 90% of drug failures in metastatic cancers. Thus, the discovery of new drugs and treatment options is critically needed to improve TNBC patient outcomes. Isorhapontigenin (ISO) is a stilbene derivative from the Chinese herb, Gnetum Cleistostachyun, and has been shown to exert anti-cancer effects in bladder, lung, and prostate cancer, but very few studies have investigated ISO in the context of TNBC. In the present study, we investigated potential anti-cancer effects on MDA-MB-231 and 4T1, human and murine TNBC cell lines, respectively. ISO significantly inhibited the proliferation and clonogenicity of TNBC cells in a dose-dependent manner. In addition, the capacity of cell migration was significantly reduced upon ISO treatment, along with increased expression of claudin-1, a tight-junction marker and tumor-suppressor. Moreover, ISO treatment reduced the size of TNBC spheroids in vitro 3D cancer model, accompanied by decreased expression of cell proliferation markers, PCNA and Ki-67. Further mechanistic studies revealed that ISO treatment significantly increased protein expression of ferroptosis suppressor protein 1 (FSP1), a recently discovered marker of chemoresistance in many cancers. Cycloheximide chase assay and MG132 treatment confirmed that ISO stabilized FSP1 protein stability in the proteasome-dependent manner. Cotreatment of ISO with an FSP1 inhibitor (iFSP1) had significant synergistic effects in reducing TNBC cell proliferation and clonogenicity. In summary, our study demonstrates that ISO inhibits TNBC cancer cell proliferation and migration. Additionally, this is the first study demonstrating the combined treatment of ISO and iFSP1 exerts robust synergistic inhibition of cell proliferation, highlighting ISO as a promising anticancer drug and support its combination with iFSP1 as a novel therapeutic strategy against TNBC. Citation Format: Franklin Tran, Yvette Shteynfeld, Sydney Tsao, Hong Sun, Wei Dai. Combination of isorhapontigenin and FSP1 inhibitor suppresses triple negative breast cancer cell progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(8_Suppl):Abstract nr LB071.

Ras proteins are integral to the mediation of signaling cascades to downstream effectors, regulating a multitude of cellular processes. Mutations within Ras and its associated signaling pathways are implicated in various human pathologies, including inflammatory disorders and malignancies. The immune checkpoint proteins, programmed cell death protein 1 (PD-1) and its ligands PD-L1, along with Indoleamine 2,3-dioxygenase-1 (IDO1), are pivotal in facilitating tumor immune escape. While the influence of oncogenic Ras on PD-L1 expression is extensively documented, the regulatory role of KRas in IDO1 expression remains inadequately understood. In the current study, we demonstrate that IDO1 and PD-L1 expressions are differentially regulated in KRas-mutant cancers. Treatment with the KRasG12C-specific inhibitor, ARS-1620, significantly increased IDO1 expression, which inversely correlated with PD-L1 expression in the KRasG12C-mutant H358 cell line. Notably, IDO1 expression was slightly diminished in KRas-mutant patients with lung and pancreatic ductal adenocarcinomas. Experimental data revealed that IFN-γ induces IDO1 expression; however, this induction is attenuated in the presence of constitutively active KRas. These findings suggest that KRas signaling negatively regulates IDO1 expression while enhancing PD-L1 expression. Moreover, the induction of IDO1 expression following KRas inhibition appears to operate independently of the MAPK pathway. Our results propose that concurrent targeting of KRas and IDO1 could potentiate therapeutic efficacy in KRas-mutant cancers, overcoming resistance to immune checkpoint blockade.

Oral squamous cell carcinoma (OSCC) is an aggressive cancer with limited improvement in patient outcomes despite advances in surgery, chemotherapy, and radiotherapy. The LIM-only protein LMO4 functions as a transcriptional co-regulator and is known to be increased in several epithelial cancers, but its contribution to OSCC has not been well defined. In this study, we found that LMO4 expression was markedly higher in OSCC tissues and was associated with poorer overall survival. Cellular experiments showed that LMO4 enhanced OSCC cell proliferation, migration, and resistance to ferroptosis by promoting the ubiquitin–proteasome–dependent degradation of the tumor suppressor RAB17. Restoration of RAB17 expression reduced these malignant behaviors. In a nude mouse xenograft model, tumors with high LMO4 grew faster and displayed lower RAB17 protein levels. Taken together, our results indicate that LMO4 contributes to OSCC progression through post-translational regulation of RAB17 and ferroptosis control, suggesting that this pathway could serve as a new therapeutic target. RAB17 and LMO4 modulate ferroptosis by regulating GPX4 expression through the Nrf2-Keap1 signaling pathway.

Traumatic brain injury (TBI), particularly at high altitudes (HA-TBI), is a leading cause of mortality and disability, yet clear diagnostic and treatment protocols are lacking. This study explores the early pathophysiological changes occurring within 24 h following HA-TBI, with a focus on differentially expressed proteins (DEPs) and phosphorylated proteins (DEPPs). Using a low-pressure hypoxic chamber to simulate high-altitude conditions combined with a controllable cortical impact (CCI) model, we established a rat model of HA-TBI. Neurological function was evaluated using the modified Neurologic Severity Score (mNSS), while neuropathological and inflammatory responses following HA-TBI were evaluated through hematoxylin and eosin (HE) staining, immunofluorescence, Western blot (WB), and Enzyme-Linked Immunosorbent Assay (ELISA). In-depth proteomic and phosphoproteomic analyses were performed on the cerebral cortex at 6, 12, and 24 h post-injury. Bioinformatic analysis identified time-dependent DEPs, revealing dynamic changes in mRNA metabolism, ATP metabolism, and MAPK signaling during the early stages of HA-TBI. Common DEPs at 6, 12, and 24 h post-injury were linked to complement and coagulation cascades. Time-dependent DEPPs influenced synaptic structure and neurotransmission, with early changes in glutamatergic synapses being especially pronounced. Key pathways, including the complement and coagulation cascades and dopaminergic synapses, emerged as central to the injury response. Furthermore, proteins such as AHSG, APOA1, GRIN2B, phospho-GSK3β-S9, and CAMK2G were identified as critical regulators in these pathways. WB validated these findings, offering new insights into the mechanisms underlying HA-TBI and highlighting potential therapeutic targets for early intervention in high-altitude trauma.

The strategy of restoring mitochondrial function by modulating mitochondrial membrane potential (MMP) through uncoupling protein 2 (UCP2) offers significant therapeutic potential against cerebral ischemia-reperfusion injury (CIRI). However, traditional strategies ignored elevation of mitochondrial reactive oxygen species (mtROS) resulting from UCP2 inhibition, resulting in poor therapeutic effects. Here, we reported a multifunctional SGB nanomedicine formed by pioneering the prepolymerization of the UCP2 inhibitor genipin and glycine and a cerebral infarction targeting peptide via a metastable imine bond. After intravenous injection, SGB was highly targeted to affected brain tissue and reached neuronal mitochondria. SGB could not only restore MMP by cleaving the metastable imine bond to release genipin to inhibit overexpressed UCP2, but also simultaneously eliminated excessive mtROS. Compared with traditional UCP2 inhibition, SGB could not only significantly improve the bioavailability of genipin and reduce systemic side effects, but also effectively protected neuronal mitochondria, reduced endoplasmic reticulum stress and inhibited the inflammatory storm of microglia, ultimately significantly reduced neuronal apoptosis. Correspondingly, SGB nearly reversed CIRI with a low 5 mg/kg dose. This innovative approach redefines the role of UCP2 inhibition and provides a framework for the treatment of CIRI by maintaining mitochondrial function.

OBJECTIVES:To investigate the inhibitory effect of polyphyllin VII (PP7) on osteosarcoma xenograft growth in mice and explore the underlying molecular mechanism. METHODS:Ultra‑performance liquid chromatography‑tandem mass spectrometry was used to analyze the main active components of Paris polyphylla. Six nude mice bearing patient‑derived xenograft (PDX) were randomized into two groups for treatment with 2 mg/kg PP7 gavage or saline every other day for 28 days, and the changes in tumor volume and mass were measured. In cultured 143B and HOS cells, the effect of PP7 treatment (0, 1.25, 2.5, 5, and 10 μmol/L) on cell proliferation was assessed with CCK‑8 assay, and Transwell assays were employed to examine the changes in cell migration and invasion. The target of PP7 was predicted by integrated analyses with single‑cell RNA sequencing (scRNA‑seq), bulk RNA sequencing (bulk RNA‑seq) and molecular docking and verified using Western blotting. In osteosarcoma cells transfected with SOHLH1 siRNAs or a negative control sequence, the effects of PP7 treatment (5 μmol/L) on cell migration, invasion, ferroptosis, reactive oxygen species (ROS) production and lipid peroxidation (LPO) were analyzed. RESULTS:PP7 was identified as one of the major active constituents of Paris polyphylla. In the tumor-bearing mice, PP7 treatment significantly lower the tumor volume and mass. In 143B and HOS cells, PP7 concentration‑dependently inhibited cell proliferation, and at 5 μmol/L, PP7 significantly inhibited cell proliferation, migration and invasion. Multi‑omics analysis identified SOHLH1 as a potential target of PP7, and Western blotting confirmed that PP7 upregulated SOHLH1 expressions at both the mRNA and protein levels. SOHLH1 silencing obviously attenuated the inhibitory effects of PP7 on cell migration and invasion and reduced PP7‑induced ferroptosis. CONCLUSIONS:PP7 suppresses osteosarcoma xenograft growth in mice by inducing ferroptosis via upregulating SOHLH1 expression.

The dysregulation of cyclin-dependent kinase 12 (CDK12), which may result from genomic alterations or modulation by upstream effectors, is implicated in cancer oncogenesis and progression. CDK12 overexpression or activation is sufficient to induce tumor initiation, recurrence, and therapeutic resistance. However, CDK12 may also exert tumor-suppressive functions in a context-dependent manner. Therefore, caution is warranted when targeting CDK12 in future clinical trials. A comprehensive elucidation of the dual roles and underlying mechanisms of CDK12 in carcinogenesis is urgently needed to advance precision oncology. This review provides an overview of the current understanding of the dysregulation and biological roles of CDK12 in cancer. Subsequently, we systematically summarize the functions and mechanisms of the oncogenic and tumor-suppressive roles of CDK12 in different contexts. Finally, we discuss the potential of CDK12 as a novel therapeutic target and its implications in clinical oncology, offering insights into future directions for innovative cancer treatment strategies.

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is pivotal in development, metabolic homeostasis, and immune responses. While recent research has highlighted AhR's significant role in modulating oxidative stress responses, its mechanistic relationship with ferroptosis—an iron-dependent, non-apoptotic cell death—remains to be fully elucidated. In our study, we discovered that AhR plays a crucial role in ferroptosis, in part by transcriptionally regulating the expression of the solute carrier family 7 member 11 (SLC7A11). Our findings indicate that both pharmacological inactivation and genetic ablation of AhR markedly enhance erastin-induced ferroptosis. This enhancement is achieved by suppressing SLC7A11, leading to increased lipid peroxidation. We also obtained evidence of post-translational modifications of SLC7A11 during ferroptosis. Additionally, we observed that indole 3-pyruvate (I3P), an endogenous ligand of AhR, protects cells from ferroptosis through an AhR-dependent mechanism. Based on these insights, we propose that AhR transcriptionally regulates the expression of SLC family genes, which in turn play a pivotal role in mediating ferroptosis. This underscores AhR's essential role in suppressing lipid oxidation and ensuring cell survival under oxidative stress.

Objective Sepsis, which is the body’s response to overwhelming infection, can lead to septic shock, characterized by thrombocytopenia, hypotension, and organ damage. Polo-like kinase 3 (Plk3) is a ubiquitously expressed serine/threonine kinase, but its exact role in immune function is unknown.Approach and Results We used Plk3−/− and WT mice to evaluate the function of Plk3 in several models of severe sepsis. We found that WT mice die within 48 hours of 100% cecal ligation and puncture (CLP), while Plk3−/− mice survive. Survival following cecal slurry (CS) injection mirrored that of CLP as recipient WT mice succumbed, while recipient Plk3−/− mice survived. Analysis of bacterial load 24 hours after CLP revealed that WT blood and peritonea were loaded with bacteria, but bacteria were virtually undetectable in the peritonea or blood of Plk3−/− mice. To determine if bacteria infiltrate the blood of Plk3−/− mice shortly after infection, we measured bacteria 1 and 3 hours after CS injection. We found a time-dependent increase in bacteria in the blood of WT mice that was not observed in Plk3−/− mice. To determine if the lack of bacteria in the blood of Plk3−/− mice is due to enhanced clearance, we injected E. coli IV into WT and Plk3−/− mice. We found 75% mortality for both WT and Plk3−/− mice within 72 hours following IV injection suggesting that survival of Plk3−/− mice following enteric infection is likely due to reduced bacteremia.Conclusion Collectively our data suggest that Plk3 supports the systemic dissemination of bacteria and subsequent sepsis following enteric infection.### Competing Interest StatementThe authors have declared no competing interest.* Plk3 : polo-like kinase 3 WT : wildtype CLP : cecal ligation and puncture CS : cecal slurry PAMP : pathogen associated molecular pattern LPS : lipopolysaccharide PRR : pattern recognition receptor TLR4 : toll-like receptor 4 GFP : green fluorescent protein IL : interleukin CIB1 : calcium- and integrin-binding protein 1 PE : phycoerythrin AST : aspartate aminotransferase ALT : alanine aminotransferase PBS : phosphate buffered saline GPIX : glycoprotein IX WBC : white blood cell LY : lymphocyte NE : neutrophil MO : monocyte Plt : platelet

While EZH2 enzymatic activity is well-known, emerging evidence suggests that EZH2 can exert functions in a methyltransferase-independent manner. In this study, we have uncovered a novel mechanism by which EZH2 positively regulates the expression of SKP2, a critical protein involved in cell cycle progression. We demonstrate that depletion of EZH2 significantly reduces SKP2 protein levels in several cell types, while treatment with EPZ-6438, an EZH2 enzymatic inhibitor, has no effect on SKP2 protein levels. Consistently, EZH2 depletion leads to cell cycle arrest, accompanied by elevated expression of CIP/KIP family proteins, including p21, p27, and p57, whereas EPZ-6438 treatment does not modulate their levels. We also provide evidence that EZH2 knockdown, but not enzymatic inhibition, suppresses SKP2 mRNA expression, underscoring the transcriptional regulation of SKP2 by EZH2 in a methyltransferase-independent manner. Supporting this, analysis of the Cancer Genome Atlas database reveals a close association between EZH2 and SKP2 expression in human malignancies. Moreover, EZH2 depletion but not enzymatic inhibition positively regulates the expression of major epithelial-mesenchymal transition (EMT) regulators, such as ZEB1 and SNAIL1, in transformed cells. Our findings shed light on a novel mechanism by which EZH2 exerts regulatory effects on cell proliferation and differentiation through its methyltransferase-independent function, specifically by modulating SKP2 expression.

The Aryl Hydrocarbon Receptor (AhR) is a ligand-activated transcriptional factor pivotal in responding to environmental stress and maintaining cellular homeostasis. Exposure to specific xenobiotics or industrial compounds in the environment activates AhR and its subsequent signaling, inducing oxidative stress and related toxicity. Past research has also identified and characterized several classes of endogenous ligands, particularly some tryptophan (Trp) metabolic/catabolic products, that act as AhR agonists, influencing a variety of physiological and pathological states, including the modulation of immune responses and cell death. Heavy metals, being non-essential elements in the human body, are generally perceived as toxic and hazardous, originating either naturally or from industrial activities. Emerging evidence indicates that heavy metals significantly influence AhR activation and its downstream signaling. This review consolidates current knowledge on the modulation of the AhR signaling pathway by heavy metals, explores the consequences of co-exposure to AhR ligands and heavy metals, and investigates the interplay between oxidative stress and AhR activation, focusing on the regulation of immune responses and ferroptosis.

Leukemia inhibitory factor receptor (LIFR), in complex with glycoprotein 130 (gp130) as the receptor for leukemia inhibitory factor (LIF), can bind to a variety of cytokines and subsequently activate a variety of signaling pathways, including Janus kinase/signal transducer and activator of transcription 3. LIF, the most multifunctional cytokines of the interleukin-6 family acts as both a growth factor and a growth inhibitor in different types of tumors. LIF/LIFR signaling regulates a broad array of tumor-related processes including proliferation, apoptosis, migration, invasion. However, due to the activation of different signaling pathways, opposite regulatory effects are observed in certain tumor cells. Therefore, the role of LIFR in human cancers varies across different tumor and tissue, despite their recognized value in tumor treatment and prognosis observation is affirmed. Given its aberrant expression in numerous tumor cells and crucial regulatory function in tumorigenesis and progression, LIFR is considered as a promising targeted therapeutic agent. This review provides an overview of LIFR's initiating signaling pathway function as a cytokine receptor and summarize the current literature on the role of LIFR in cancer and its possible use in therapy.

Figure S1 - Biological and pharmacological inhibition of EZH2 potently dampens growth of IM-sensitive and -resistant CML cells; Figure S2 - GSK126 induces apoptosis in CML cells in a dose- and time-dependent manner; Figure S3 - GSK126 elicits cytochrome c release and mitochondrial damage; Figure S4 - Administration of GSK126 in CML mice reduces LSCs in spleen nucleated cells from CML mice; Figure S5 - Knockdown of EZH2 reduces in vivo LSCs in CML mice; Figure S6 - Pharmacological and biological inhibition of EZH2 in CML mice has minimal effect on LSCs and progenitor cells in BM and spleen nucleated cells from CML mice; Figure S7 - BCR-ABL is not involved in the EZH2 knockdown-enabled PTEN transcriptional elevation; Figure S8 - Knockdown of PTEN weakens the effect of LSCs reduction mediated by silencing EZH2.

List of 349 differentially expressed genes in normal-looking colonic mucosal tissues in Sgo1, compared with control wild type. (P<0.05, 2-fold cutoff)

Soil arsenic (As) pollution not only decreases plant productivity but also soil quality, in turn hampering sustainable agricultural development. Despite the negative effects of As contamination on rice yield and quality being reported widely, the responses of microbial communities and co-occurrence networks in paddy soil to As pollution have not been explored. Here, based on high-throughput sequencing technologies, we investigated bacterial abundance and diversity in paddy soils with different levels of As contamination, and constructed associated microbial co-occurrence networks. As pollution reduced soil bacterial diversity significantly (p < 0.001). In addition, bioavailable As concentrations were negatively correlated with Actinobacteria and Acidobacteria relative abundance (p < 0.05). Conversely, As pollution had a positive relationship with Chloroflexi, Betaproteobacteria, and Bacteroidetes relative abundance (p < 0.05). Firmicutes relative abundance decreased with an increase in total As concentration. The ecological clusters and key groups in bacterial co-occurrence networks exhibited distinct trends with an increase in As pollution. Notably, Acidobacteria play an important role in maintaining microbial networks in As contaminated soils. Overall, we provide empirical evidence that As contamination influences soil microbial community structure, posing a threat to soil ecosystem health and sustainable agriculture.

Table S1 shows the Characteristics of patients with CML; Table S2 shows the sequence of shRNA; Table S3 shows the limiting dilution assay of mouse LT-HSC after shEZH2 treatment

Supplement 1 from Polo-like Kinase 3 Functions as a Tumor Suppressor and Is a Negative Regulator of Hypoxia-Inducible Factor-1α under Hypoxic Conditions

Skp2, an F box protein and a substrate-binding component of the SCFSkp2 ubiquitin E3 ligase complex, promotes ubiquitination and degradation of cyclin-dependent kinase inhibitors (CKIs), including p21, p27, and p57. Aberrant Skp2 expression is associated with many human cancers. EZH2 (Enhancer of Zeste Homologue 2) is a core catalytic subunit of the polycomb repressive complex 2 (PRC2) that can regulate gene expression by mediating the methylation of lysine 27 of histone H3 (H3K27me3). Accumulating evidence shows that EZH2 could bind to transcription factors and activate gene expression independently of its methyltransferase activity, leading to the activation of oncogenic signaling pathways and promoting the proliferation of tumor cells. Although the methyltransferase-independent function of EZH2 is important in cell proliferation, its mechanism in cell cycle regulation is still unclear. In this study, we demonstrate that EZH2 positively regulates Skp2 gene expression. We show that suppression of EZH2 expression resulted in a significant decrease of Skp2 protein levels, while the EZH2 enzymatic inhibitors, EPZ6438, had no impact on protein levels of Skp2, which suggests that EZH2 regulates Skp2 expression independently of its methyltransferase activity. Consistently, EZH2 depletion reduced the mRNA levels of Skp2, while EPZ6438 inhibited EZH2 methyltransferase activity without affecting the mRNA levels of Skp2. Importantly, EZH2 expression is positively correlated with the expression of EMT (Epithelial-mesenchymal transition) regulators (YAP1/TAZ, ZEB1, and Snail) and immune checkpoint proteins (FGL1 and Siglec-15) in cervical and pancreatic cancer cells, but reversely correlated with the expression of CKIs (p21, p27, and p57). Taken together, our findings suggest a novel mechanism by which EZH2 regulates tumorigenesis through its methyltransferase-independent function by regulating Skp2 expression. Targeting the methyltransferase-independent function of EZH2 may have therapeutic efficacy for cancer patients. Citation Format: Tania Marlyn Colon, Wei Dai, Byeong Hyeok Choi. Regulation of SKP2 expression by methyltransferase-independent function of EZH2 in tumor growth and progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1423.

Ras proteins are among the most widely studied proto‐oncogene products. Ras proteins are membrane‐anchored GTPases that participate in multiple signaling cascades regulating crucial cellular processes including cell survival, proliferation, and differentiation. Ras mutations and/or deregulated Ras activities frequently lead to inflammation and malignant transformation. Recent studies have also shown that Ras mutations are associated with immuno‐resistance by positive regulation of PD‐L1 expression. Indoleamine 2,3‐dioxygenases 1 (IDO1) is a heme‐containing enzyme that catalyzes the rate limiting step of conversion of tryptophan into kynurenine (Kyn). Extensive research in the past has shown that IDO1 and its catalytic product Kyn mediate immune tolerance, thus promoting tumorigenesis in vivo. IDO1 expression is activated by immune cytokines including interferon‐γ (IFN‐γ)and interleukin‐6 (IL‐6). However, whether there is a mechanistic link between oncogenic KRas and IDO1 expression and how IDO1 expression contributes to immune invasion of transformed cells with KRas mutations remain unclear. Here we report that oncogenic KRas significantly enhanced IFN‐γ‐induced IDO1 expression. In H358 lung carcinoma cells, IDO1 expression induced by IFN‐γ was at least in part dependent on ERK activation, and treatment with ARS‐1620, a covalent KRasG12C inhibitor, suppressed IDO1 expression induced by IFN‐γαμμα in a concentration‐dependent manner. IDO1 expression was also induced by IFN‐γ in HCT116 colon carcinoma cells that harbored a KRasG12D mutant allele, but not in HCT116 cells with wild‐type KRas, suggesting that IFN‐γ induced IDO1 expression requires Ras activation. In addition, KRas downregulation by specific siRNAs decreased IFN‐γ‐induced IDO1 expression in A549 lung cancer cells. Taken together, our study strongly suggests that Ras/ERK signaling pathway plays an important role in promoting IDO1 expression induced by IFN‐γ.