Owing to their robust antioxidant defense mechanisms, cancer stem-like cells (CSCs) maintain a low level of oxidative stress, which is crucial for preserving stemness and pluripotency. Therefore, agents that either directly generate reactive oxygen species (ROS) or inhibit the antioxidant defense systems can selectively induce oxidative cell death in CSCs. Loss of the tumor suppressor gene LKB1 makes CSCs more vulnerable to oxidative damage, as these cells cannot sense energy stress. In the present study, LKB1 wild-type (WT) and LKB1 mutant isogenic non-small cell lung cancer (NSCLC) cells were grown in sphere culture media, which enriches the CSC population, and treated with mitomet, an analog of the antidiabetic drug metformin. Subsequently, effects on self-renewal of spheres, mitochondrial membrane potential (MMP), ATP synthesis, expression of self-renewal-, cell proliferation/survival-, redox metabolism-, and lipid synthesis-related proteins, mitochondrial ROS (mROS), lipid peroxidation, and cell proliferation/survival were determined. Mitomet differentially increased mROS in LKB1 mutant tumor spheres, thereby suppressing levels of MMP, ATP synthesis, GPX4, and phospho-ACC, which then culminated in increased lipid peroxidation and cell death. Mitomet-induced lipid peroxidation and cell death were reversed by liproxstatin, a potent inhibitor of ferroptosis, indicating that mitomet-induced cell death was mediated via ferroptosis. Interestingly, Torin-1, an mTOR inhibitor, significantly potentiated lipid peroxidation and ferroptosis induced by mitomet. Our findings establish the potential of mitomet, especially when combined with mTOR inhibitors, for the prevention and treatment of LKB1 mutant lung cancer by targeting CSCs.

NAT10, an essential enzyme catalyzing RNA ac⁴C modification, is recognized as a critical regulator of tumorigenesis and progression. This study investigates the role and underlying molecular mechanisms of NAT10 in breast cancer. We found that NAT10 is significantly overexpressed in breast cancer tissues compared to adjacent normal tissues, exhibiting high diagnostic accuracy (AUC = 0.9702, p < 0.001). Consistently, NAT10 expression was also elevated in breast cancer cell lines. Knockdown of NAT10 potently inhibited cell viability, glycolysis (as indicated by reduced glucose uptake, lactate production, and ECAR), and metastatic potential (manifested as suppressed migration and invasion) in breast cancer cells. Mechanistically, NAT10 regulated TRAF6 expression and stability through ac⁴C modification; NAT10 knockdown led to reduced ac⁴C enrichment on TRAF6 mRNA and accelerated its degradation. Rescue experiments confirmed that TRAF6 overexpression partially reversed the inhibitory effects of NAT10 knockdown on glycolysis and metastasis. In vivo, NAT10 knockdown significantly suppressed tumor growth in nude mice, which was associated with reduced expression of Ki67 and TRAF6 in tumor tissues. Collectively, our findings highlight NAT10 as a key regulator of breast cancer progression via ac⁴C-mediated TRAF6 modulation, suggesting it as a promising therapeutic target for breast cancer therapy.

Cutaneous squamous cell carcinoma (cSCC) is a malignant skin cancer which is derived from epidermal keratinocytes, and long-term exposure to ultraviolet rays is its main risk factor. Procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2) is a crucial gene for the formation and stability of collagen intermolecular cross-links, being vital in the development of cancer. Nevertheless, the interaction between cSCC and PLOD2 has not been elucidated. Here, we found PLOD2 upregulated in human cSCC. Its knockdown in cSCC cells suppressed proliferation, migration, invasion, and angiogenesis while inducing apoptosis and cell cycle arrest; overexpression promoted these malignant phenotypes. In mouse xenografts, PLOD2 knockdown inhibited tumor growth and collagen deposition. Furthermore, in a DMBA/TPA-induced carcinogenesis model, topical PLOD2 inhibition by minoxidil suppressed tumor development as well. Mechanistically, our studies revealed that PLOD2 acts as a key downstream effector of STAT3 to activate ERK and AKT signaling evidenced by rescue experiments. As a result, our study not only establishes the STAT3/PLOD2/ERK-AKT axis as a key driver of cSCC but also identifies the clinically approved drug minoxidil as a potent PLOD2 inhibitor, demonstrating immediate promise as a repurposed therapeutic agent.

Our previous preclinical studies demonstrated that non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin and naproxen significantly inhibited prostate tumorigenesis in a TMPRSS2-ERG fusion-driven model compared to non-fusion models. Since TMPRSS2-ERG fusion-positive tumors display heightened inflammatory signaling and substantial immune infiltration, we hypothesized that the differential efficacy of NSAIDs may arise from their ability to remodel the tumor immune microenvironment. Accordingly, in the present study, we systematically profiled innate and adaptive immune-cell populations: F4/80⁺ macrophages, mast cells, neutrophils, CD3⁺ T cells, CD8⁺ cytotoxic T cells, FoxP3⁺ regulatory T cells, CD20⁺ B cells, IgKC⁺ plasma cells, and Granzyme B⁺ effector cells in highly infiltrated dorso-lateral prostate regions of TMPRSS2-ERG fusion-driven and non-fusion PCa models, with and without NSAID intervention. Our analyses revealed pronounced macrophage infiltration in TMPRSS2-ERG. Ptenflox/flox and Hi-Myc+/ - model, which was further augmented by NSAIDs. Importantly, NSAID intervention shifted macrophage polarization toward an M1-like, pro-inflammatory state, contrasting with the M2-dominant phenotype characteristic of untreated tumors. NSAID treatment reduced mast cell density within the stromal compartment, suggesting suppression of mast cell-mediated tumor-promoting signals. In the fusion model, infiltration of total T cells and CD8⁺ cytotoxic T cells decreased following NSAID exposure, whereas FoxP3⁺ Tregs remained largely unaffected. Both models showed increased B-cell infiltration independent of NSAID efficacy, and no clear correlation was observed between plasma-cell presence and treatment response. Collectively, our findings offer new insight into NSAID-mediated immunomodulation in TMPRSS2-ERG fusion-driven PCa; however, further in-depth immune subtyping and spatial mapping could fully delineate the immunological mechanisms driving NSAID responsiveness.

Canine hepatocellular carcinoma (HCC) requires further molecular characterization to identify diagnostic and therapeutic targets, and to establish whether dogs with this condition can model the human disease. Accordingly, we aimed to identify differentially expressed genes (DEGs) in canine HCC and evaluate cross-species transcriptomic dysregulation in canine and human HCC. Liver tissue samples from three dogs with HCC and three healthy dogs were subjected to next-generation sequencing, followed by RT-qPCR validation. Identified DEGs were then targeted in bioinformatics analyses (pathway enrichment, protein-protein interaction network, and hub gene analyses) for molecular characterization and comparison with human HCC datasets. We identified 975 DEGs (upregulated: 604; and downregulated: 371). Extracellular matrix-receptor interaction, focal adhesion, cell adhesion molecule, PI3K/Akt signaling, and cytokine/chemokine-related pathways were enriched. C1R, APOC3, C1QA, APOA1, C1QB, ACTG1, C1QC, CRP, ANXA5, and ANXA2 were identified as hub genes. Canine and human HCCs share 118 DEGs, highlighting conserved alterations in metabolic pathways, PI3K-Akt signaling, focal adhesion, and PPAR signaling pathways. Based on human HCC data, SPP1, NQO1, RRM2, APOA1, APOC3, ALDOB, and IGF1 were identified as prognosticators indicating poor overall survival. This study presents the first cross-species transcriptomic analysis of canine HCC, revealing significant molecular resemblances to human HCC, indicating it may be a promising comparative model for studying tumor biology, drug responses, and novel therapeutic interventions.

Cyclin L1 (CCNL1) is highly expressed in multiple cancer types and has been linked to poor prognosis. However, the expression pattern of CCNL1 in breast cancer and its specific role in regulating breast cancer progression remain largely unknown. This study used cell and molecular biology techniques to examine how CCNL1 regulates the proliferation, invasion, migration, and epithelial-mesenchymal transition (EMT) of breast cancer cells. The applied methods encompassed plasmid transfection, Transwell assay, wound-healing assay, Western blot analysis, co-immunoprecipitation (Co-IP), and rescue assay. For the analysis of CCNL1-related factors and pathways, bioinformatics platforms including Metascape and HURI were also employed. CCNL1 is highly expressed in breast cancer cells and is associated with a poor prognosis. CCNL1 overexpression increased breast cancer cell invasion and migration and accelerated proliferation. Overexpression of CCNL1 was found to upregulate the mesenchymal marker Vimentin and downregulate the epithelial marker E-cadherin expression. There is close relationship between CCNL1, the NF-κB and PI3K/AKT signaling pathways. The direct interaction is verified between CCNL1 and DVL3 by Co-IP, indicating a negative correlation between the two proteins. CCNL1 overexpression affects breast cancer cells' paclitaxel sensitivity through the PI3K/AKT pathway. CCNL1 activates the NF-κB signaling pathway through its interaction with DVL3; additionally, it promotes the PI3K/AKT pathway. Together, these two mechanisms enable CCNL1 to exert a regulatory role in the progression of breast cancer.

ABSTRACTRadiotherapy (RT) has evolved significantly since its inception from treating benign conditions to becoming a cornerstone of cancer treatment. This review examines the complex interactions between RT and the immune system, highlighting its diverse effects on various immune cell populations, and exploring emerging strategies to enhance therapeutic outcomes. We discuss lessons learned from the re‐emergence of low‐dose irradiation for non‐malignant disorders, the use of RT in managing graft‐versus‐host disease, and the importance of fractionation in modulating immune responses. This review addresses abscopal effects and their clinical implications. We emphasize the critical role of tumor‐draining lymph nodes in mediating systemic immune responses. Recent advancements, including FLASH radiotherapy and targeted approaches to preserving immune function, have been explored. By integrating historical insights with contemporary research, this review aims to guide future RT practices and optimize their immunomodulatory potential, while minimizing adverse effects. We conclude by emphasizing the need for personalized approaches, biomarker identification, and innovative combination therapies to maximize the efficacy of RT in oncology.

Metastatic cells migrate from primary tumors and persist as dormant clusters. The mechanisms that allow these cells to escape their dormant state are an area of intense investigation. Protein phosphatase 2 (PPP2) is a tumor suppressor that dephosphorylates protein kinases involved in proliferation and metastasis. Increased PPP2 expression has been associated with progression-free survival in head and neck cancer (HNSC). A frequently altered epigenetic modifier in HNSC is the lysine demethylase KDM5A. KDM5A catalyzes demethylation of histone H3K4, resulting in chromatin compaction and repression of target genes. Despite the frequency of altered KDM5A expression in HNSC, the mechanism by which it regulates the progression of these cancers is unclear. Our present study demonstrates, using novel genetically engineered models, that PPP2 inhibition results in escape from metastatic dormancy via increased target protein phosphorylation, IL10 expression, and lymphocyte depletion. Genomic analysis demonstrated that KDM5A directly targets the PPP2 catalytic subunit. Genetic inhibition of KDM5A expression in vivo promotes HNSC metastatic dormancy via decreased IL10 expression. CRISPR-mediated ablation of KDM5A expression inhibits the proliferation of HNSC lines, and treatment with a small molecule KDM5A inhibitor results in the death of these cells. We concluded that PPP2 is required for HNSC metastatic dormancy and is regulated by KDM5A.

ABSTRACTOral administration of broccoli constituent sulforaphane (SFN) prevents prostate cancer development in preclinical mouse models. However, the mechanism(s) underlying prostate cancer prevention by SFN are not fully understood. In this study, we used a human relevant mouse model (Hi‐Myc mice) to demonstrate restoration of immune surveillance by oral SFN administration. Treatment of Hi‐Myc mice with SFN for 16 weeks resulted in about 1.33‐fold increase in the number of prostate tumor‐infiltrating CD8α + T cells (p = 0.02 by Student's t‐test). The number of CD4+ helper T cells was not affected by SFN treatment. The number of CD11c/MHCII+ dendritic cells was increased by about 57% upon SFN administration. On the other hand, the number of NKp46+ natural killer cells was not significantly affected by SFN treatment. Oral administration of SFN resulted in about 30% decrease in the number of Gr1/CD11b+ myeloid‐derived suppressor cells in the prostate tumor when compared to control mice. Plasma levels of interleukin (IL)−1α, IL‐1β, IL‐4, IL‐5, IL‐10, and C‐X‐C motif chemokine ligand 2 (CXCL2 or MIP‐2) were statistically significantly lower in SFN‐treated mice when compared to control mice. Treatment of recurrent prostate cancer patients with 200 μmol/day of SFN‐rich broccoli sprout extract for 20 weeks also caused a statistically significant decrease in plasma levels of IL‐1β, IL‐4, and IL‐13. Cell proliferation inhibition by SFN in vitro was partially but significantly attenuated by IL‐4 and IL‐13 supplementation in 22Rv1 cells. These results indicate restoration of immune surveillance by oral SFN treatment in Hi‐Myc mouse model.