The Diverse Roles of Heme Oxygenase-1 in Tumor Progression

The neuroprotective role of CncC in a Drosophila model of Parkinson's disease

Parkinson's disease (PD) is an incurable neurodegenerative disorder, yet significant advancements have been made in understanding its etiology. Among the risk factors, exposure to neurotoxins plays the greatest role. One of the most dangerous toxins is rotenone, a naturally derived compound that was historically used as an insecticide. This chemical affects mitochondrial function by blocking electron transfer, resulting in increased reactive oxygen species production and accumulation. Recently, the role of the Nrf2 pathway was explored as a possible protective mechanism to minimize the neurotoxic effects leading to Parkinson's disease. Here, we used Drosophila melanogaster as a model to examine the link between the expression or activity levels of CncC (an ortholog of Nrf2) or HO (an ortholog of HO-1) in the brain and the detrimental effects of chronic exposure to rotenone. We found that flies with overexpression of CncC or silencing of ho survived better after exposure to rotenone compared with flies with partially suppressed CncC or upregulated ho expression. These experimental groups exposed to rotenone also exhibited significantly fewer degenerated dopaminergic (DA) neurons than did the wild-type group. Nevertheless, only those in which CncC was overexpressed in glia showed the best survival, the greatest percentage of climbing ability, and no effects on DA neurons. Our findings were supported by data obtained for flies fed with HO inhibitor (SnPPIX) or activator (hemin), as well as with curcumin (Nrf2 activator). The observed effects were connected with changes in autophagy and apoptosis pathways. Our data suggest that possible therapies exploiting Nrf2 activation should include restricting HO upregulation as a neuroprotective strategy against the toxic effects of rotenone.

Plasma haem oxygenase-1 may represent a first-in-class biomarker of oxidative stress in rheumatoid arthritis

OBJECTIVES

This study explores the early identification of rheumatoid arthritis (RA) patients at elevated risk of progression. Haem-oxygenase-1 (HO-1) is a marker of oxidative stress in inflammation. Here, we investigate HO-1 as a biomarker of oxidative stress and its association with clinical disease activity and radiographic progression in RA.

METHOD

Baseline HO-1 was measured sequentially in plasma samples from patients with early rheumatoid arthritis (eRA) (n = 80). Disease Activity Score based on 28-joint count-C-reactive protein, Clinical Disease Activity Index, and total Sharp score were used to evaluate the disease course serially over 2 years. Paired plasma and synovial fluid samples were examined for HO-1 in active established rheumatoid arthritis (esRA) (n = 20). Plasma from healthy control subjects was also included (n = 35).

RESULTS

Plasma HO-1 levels were increased in eRA {1373 pg/mL [interquartile range (IQR) 1110-2050]} and esRA [2034 pg/mL (IQR 1630-2923)] compared with controls [1064 pg/mL (IQR 869.5-1378)]. HO-1 plasma levels decreased with treatment. Baseline HO-1 correlated with disease activity and radiographic progression. A strong, linear correlation was found between synovial and plasma HO-1 levels (r = 0.75, p < 0.001).

CONCLUSION

In eRA, plasma levels of HO-1 were increased and correlated with disease and radiographic progression. A baseline measurement of plasma HO-1 levels demonstrated superior performance to currently used clinical and serological disease markers in the prediction of radiographic progression. Plasma HO-1 may function as a first-in-class biomarker of synovial oxidative stress in RA.

The interplay between the myeloperoxidase-hypochlorous acid system, heme oxygenase, and free iron in inflammatory diseases

Accumulated unbound free iron (Fe(II or III)) is a redox engine generating reactive oxygen species (ROS) that promote oxidative stress and inflammation. Iron is implicated in diseases with free radical pathology including cardiovascular, neurodegenerative, reproductive disorders, and some types of cancer. While many studies focus on iron overload disorders, few explore the potential link between the myeloperoxidase-hypochlorous acid (MPO-HOCl) system and localized iron accumulation through heme and iron‑sulfur (FeS) cluster protein destruction. Although inducible heme oxygenase (HO-1), the rate-limiting enzyme in heme catabolism, is frequently associated with these diseases, we hypothesize that HOCl also contributes to the generation of free iron and heme degradation products. Furthermore, HO-1 and HOCl may play a dual role in free iron accumulation by regulating the activity of key iron metabolism proteins. Enzymatic and non-enzymatic modulators, as well as scavengers of HOCl, can help prevent heme destruction and reduce the accumulation of free iron. Given iron's role in disease progression and severity, identifying the primary sources, mechanisms, and mediators involved in free iron generation is crucial for developing effective pharmacological treatments. Further investigation focusing on the specific contributions of the MPO-HOCl system and free iron is necessary to explore novel strategies to mitigate its harmful effects in biological systems.

COX-2 Inhibition in Glioblastoma Cells Counteracts Resistance to Temozolomide by Inducing Oxidative Stress

Oxidative stress critically influences the pathophysiology of glioblastoma (GBM), a deadly and aggressive brain tumor. Reactive oxygen species (ROS) regulate cancer cell homeostasis, influencing the treatment response. The transcription factor Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2) activates antioxidant defenses, protecting GBM cells from therapy-induced oxidative stress and contributing to Temozolomide (TMZ) resistance. Cyclooxygenase-2 (COX-2) plays a key role in GBM chemoresistance by modulating the tumor microenvironment and supporting a pro-survival phenotype. The impact of COX-2 inhibition by celecoxib (CXB), a selective COX-2 inhibitor, combined with TMZ on oxidative stress modulation linked to resistance was investigated in GBM primary cultures and cell lines. The drug combination CXB+TMZ was tested on TMZ-sensitive and -resistant cells, and ROS levels and Nrf2 activation were evaluated via a DCFH-DA probe and Western blotting, respectively. The oxidative stress marker malondialdehyde and antioxidant enzymes were assayed using standard methods. COX-2 inhibition combined with TMZ significantly increased ROS, while TMZ alone induced a compensatory antioxidant response, sustaining resistance. Drug combination reduced this response, restoring oxidative stress even in TMZ-resistant cells. Prostaglandin E2 reversed these effects, confirming the role of the COX-2/PGE2 axis in redox balance. Drug combination increased ROS, disrupted redox homeostasis and overcame TMZ resistance, supporting COX-2 inhibition as a promising GBM therapy strategy.

Current developments of pharmacotherapy targeting heme oxygenase 1 in cancer (Review)

Malignant tumors are non-communicable diseases that impact human health and quality of life. Identifying and targeting the underlying genetic drivers is a challenge. Heme oxygenase-1 (HO-1), a stress-inducible enzyme also known as heat shock protein 32, plays a crucial role in maintaining cellular homeostasis. It mitigates oxidative stress-induced damage and exhibits anti-apoptotic properties. HO-1 is expressed in a wide range of malignancies and is associated with tumor growth. However, the precise role of HO-1 in tumor development remains controversial. Drugs, both naturally occurring and chemically synthesized, can inhibit tumor growth by modulating HO-1 expression in cancer cells. The present review aimed to discuss biological functions of HO-1 pharmacological therapies targeting HO-1.

Recent advances in the role of gasotransmitters in necroptosis

Necroptosis is a finely regulated programmed cell death process involving complex molecular mechanisms and signal transduction networks. Among them, receptor-interacting protein kinase 1 (RIPK1), receptor-interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein are the key molecules regulating this process. In recent years, gasotransmitters such as nitric oxide, carbon monoxide and hydrogen sulfide have been suggested to play a regulatory role in necroptosis. This paper reviews the evidence that these gasotransmitters are involved in the regulation of necroptosis by influencing the production of reactive oxygen species, regulating the modification of S subunits of RIPK1 and RIPK3, regulating inflammatory mediators, and signal transduction. In addition, this review explores the potential therapeutic applications of these gasotransmitters in pathological conditions such as cardiovascular disease and ischemia-reperfusion injury. Although some studies have revealed the important role of gasotransmitters in necroptosis, the specific mechanism of action is still not fully understood. Future research is needed to further elucidate the molecular mechanisms of gasotransmitters in precisely regulating necroptosis, which will help develop new therapeutic strategies to prevent and treat related diseases.

Carbon monoxide potentiates the effect of corticosteroids in suppressing inflammatory responses in cell culture

Inflammation is a pathology implicated in a wide range of human diseases. Recent years have seen tremendous progress in developing new types of anti-inflammatory agents for the treatment of inflammation of various origins. However, each has its own strengths and weaknesses. The very fact that there needs to have multiple types of anti-inflammatory agents underlines the complexity of inflammatory diseases and conditions, their molecular origins, and their treatment. Such complexity dictates the need to search for new approaches with improved potency and efficacy as well as reduced side effects. For these reasons, we are interested in exploring the possibility of generating synergy between carbon monoxide (CO), an endogenously produced cytoprotective agent, and known anti-inflammatory agents. Herein, we report the potentiating actions of CO on the anti-inflammatory effects of cortisone and dexamethasone as demonstrated in their ability to suppress the expression of TNF-α and IL-6 induced by either LPS or the S protein of SARS-CoV-2. Such effects are reflected in the substantially increased potency as well efficacy, when the efficacy of the corticosteroid alone does not allow for complete suppression of the expression of these cytokines. Further, increased attenuation of p65 phosphorylation is at least part of the molecular mechanism for the observed potentiating effects. We hope our work will stimulate a high level of activity along the same direction, leading to anti-inflammatory strategies with improved potency and efficacy and reduced side effects.

Synergistic effects of HO-1 inhibition and chemotherapy on tumor proliferation and immune infiltration: An in vitro and in vivo approach to enhancing prostate cancer treatment

Prostate cancer (PC) remains a leading cause of morbidity and mortality among men worldwide, highlighting the need for novel therapeutic strategies. Our study investigates the therapeutic potential of targeting the heme degradation pathway through heme oxygenase-1 (HO-1) inhibition in PC. Using both in vitro and in vivo models, we explored the effects of combining HO-1 inhibition with chemotherapy, represented by docetaxel (Doc), on tumor growth and immune infiltration. In vitro experiments demonstrated that HO-1 inhibition, as well as HO-1 knockout (KO), significantly reduced tumor cell proliferation and enhanced chemosensitivity in RM-1 cells. Additionally, U937 cells co-cultured with HO-1 KO cells shifted cell polarization toward an M1 phenotype. In vivo, the combined treatment of the HO-1 inhibitor, tin protoporphyrin (SnPP), with Doc significantly enhanced anti-tumor efficacy in mouse models compared to chemotherapy or SnPP alone. This combination therapy not only reduced Ki67 expression and increased CC3 expression in tumor tissues but also shifted macrophage polarization toward an M1 phenotype and enhanced CD4+ and CD8+ T cells infiltration, indicating an augmented immune response. Further investigation using macrophage-specific HO-1 knockout mice revealed a direct role of HO-1 inhibition in driving macrophage polarization, confirming its involvement in promoting the shift toward an M1 phenotype. Although this response was significant, it was more robust with systemic HO-1 inhibition. Our findings indicate that HO-1 inhibition can potentiate the effects of chemotherapy, offering a promising avenue for improving PC treatment outcomes.

Artificial blood-hope and the challenges to combat tumor hypoxia for anti-cancer therapy

The blood plays a vital role in the human body and serves as an intermediary between various physiological systems and organs. White blood cells, which are a part of the immune system, defend against infections and regulate the body temperature and pH balance. Blood platelets play a crucial role in clotting, the prevention of excessive bleeding, and the promotion of healing. Blood also serves as a courier system that transports hormones to facilitate communication and synchronization between different organs and systems in the body. The circulatory system, comprised of arteries, veins, and capillaries, plays a crucial role in the efficient transportation and connection of vital nutrients and oxygen. Despite the importance of natural blood, there are often supply shortages, compatibility issues, and medical conditions, which make alternatives such as artificial blood necessary. This is particularly relevant in cancer treatment, which was the focus of our study. In this study, we investigated the potential of artificial blood in cancer therapy, specifically to address tumor hypoxia. We also examined the potential of red blood cell substitutes such as hemoglobin-based oxygen carriers and perfluorocarbons. Additionally, we examined the production of hemoglobin using E. coli and the role of hemoglobin in oncogenesis. Furthermore, we explored the potential use of artificial platelets for cancer treatment. Our study emphasizes the significance of artificial blood in improving cancer treatment outcomes.

Involvement of STAT3 activation in ameliorating all-trans-retinal-induced ferroptosis in photoreceptor-derived 661W cells in vitro

Ferroptosis, a form of iron-dependent programmed cell death, has emerged as a critical player in various diseases, including retinal degenerative disorders. Previous studies have highlighted that ferroptosis, triggered by all-trans-retinal (atRAL) accumulation in photoreceptor cells, contributes significantly to the pathogenesis of dry age-related macular degeneration (AMD) and autosomal recessive Stargardt's disease (STGD1). However, the underlying molecular mechanisms regulating this process remain poorly understood. In this study, we explore the involvement of signal transducer and activator of transcription 3 (STAT3) in the regulation of atRAL-induced 661W photoreceptor cells (mouse-derived photoreceptor cells) ferroptosis. We found that atRAL treatment induces phosphorylation of STAT3 in 661W photoreceptor cells. Meanwhile, we also discovered that the accumulation of Reactive oxygen species (ROS) induced by atRAL partly contributes to the activation of STAT3 in 661W photoreceptor cells. Importantly, our data suggest that inhibition of STAT3 phosphorylation, resulting in increased lipid peroxidation through upregulation of the acyl-CoA synthetase long-chain family member 4 (ACSL4) and prostaglandin-endoperoxide synthase 2 (PTGS2) gene, exacerbates ferroptosis in atRAL-loaded 661W photoreceptor cells. Additionally, our findings further confirm that STAT3 activator Colivelin may significantly reduce ferroptosis in 661W photoreceptor cells exposed to atRAL by regulating the ACSL4 and PTGS2 gene. Overall, these results revealed that activated STAT3 mitigates atRAL-induced ferroptosis in photoreceptor cells, possibly by reducing ACSL4 and PTGS2 gene expression. This pathway highlights the therapeutic potential of STAT3 as a novel target for treating dry AMD and STGD1.

Prostate cancer-selective anticancer action of an oxindole derivative via HO-1-mediated disruption of metabolic reprogramming

Prostate cancer, the second leading cause of cancer-related mortality in men, exhibits distinct metabolic reprogramming involving zinc and citrate metabolism. This study investigated whether targeting this unique metabolic profile could offer an effective therapeutic approach. A series of novel oxindole derivatives were synthesized and evaluated for their inhibitory effects on transcription factors (TFs) and antiproliferative activity across various cancer cell lines. Among these, compound 3D showed the strongest inhibition of master TFs (HIF-1α, c-Myc, and SP-1) and demonstrated selective antiproliferative activity in prostate cancer cells. In PC-3 and LNCaP cells, compound 3D suppressed aerobic glycolysis by downregulating lactate-modulating genes (LDHA, MCT1/4, and CAIX) and the zinc influx transporter (ZIP1), without affecting the zinc efflux transporter (ZnT4). Notably, 3D selectively increased heme oxygenase-1 (HO-1) levels in prostate cancer cells, as shown by the proteome profiler oncogene array assay and confirmed by Western blotting. This response was reversed by ZnCl2 treatment. The decreases in LDHA, mitochondrial mass (measured by FACS), and cell proliferation induced by compound 3D were blocked by HO-1-IN-1, an HO-1 inhibitor, and ZnCl2. Furthermore, 3D induced a more pronounced reduction in the oxygen consumption rate (OCR) than in the extracellular acidification rate (EACR), indicating a strong effect on oxidative metabolism. 3D exhibited dose-dependent antitumour efficacy in vivo comparable to that of docetaxel. These findings reveal that the oxindole derivative 3D substantially lowers intracellular zinc levels, yielding potent antitumour effects in prostate cancer through HO-1 upregulation, which impairs mitochondrial function more significantly than aerobic glycolysis.

The Heme Oxygenase/Biliverdin Reductase System and Its Genetic Variants in Physiology and Diseases

Heme oxygenase (HO) metabolizes heme into ferrous iron, carbon monoxide (CO), and biliverdin-IXα (BV), the latter being reduced into bilirubin-IXα (BR) by the biliverdin reductase-A (BVR). Heme oxygenase exists as two isoforms, HO-1, inducible and involved in the cell stress response, and HO-2, constitutive and committed to the physiologic turnover of heme and in the intracellular oxygen sensing. Many studies have identified genetic variants of the HO/BVR system and suggested their connection in free radical-induced diseases. The most common genetic variants include (GT)n dinucleotide length polymorphisms and single nucleotide polymorphisms. Gain-of-function mutations in the HO-1 and HO-2 genes foster the ventilator response to hypoxia and reduce the risk of coronary heart disease and age-related macular degeneration but increase the risk of neonatal jaundice, sickle cell disease, and Parkinson's disease. Conversely, loss-of-function mutations in the HO-1 gene increase the risk of type 2 diabetes mellitus, chronic obstructive pulmonary disease, and some types of cancers. Regarding BVR, the reported loss-of-function mutations increase the risk of green jaundice. Unfortunately, the physiological role of the HO/BVR system does not allow for the hypothesis gene silencing/induction strategies, but knowledge of these mutations can certainly facilitate a medical approach that enables early diagnoses and tailored treatments.

The Beneficial Effects of CGK012 Against Lipopolysaccharide-Induced Inflammation

This study investigates the protective effects of CGK012 [(7S)-(+)-cyclopentyl carbamic acid 8,8-dimethyl-2-oxo-6,7-dihydro-2H,8H-pyrano[3,2-g]chromen-7-yl-ester], a small-molecule inhibitor targeting the Wnt/β-catenin signaling pathway, against inflammatory responses elicited by lipopolysaccharide (LPS). The study evaluated the influence of CGK012 on heme oxygenase (HO)-1, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) expressions in LPS-stimulated human endothelial cells. It examined its effects on iNOS, tumor necrosis factor (TNF)-α, and interleukin (IL)-1β in LPS-challenged mice. CGK012 treatment resulted in increased HO-1 production, inhibited nuclear factor-kappa B activation, and decreased the levels of COX-2/PGE2 and iNOS/NO. Additionally, CGK012 reduced signal transducer and activator of transcription-1 phosphorylation and facilitated Nrf2 nuclear translocation and binding to antioxidant response elements, culminating in reduced IL-1β production in LPS-exposed human umbilical vein endothelial cells. Notably, the inhibitory effect of CGK012 on iNOS/NO was reversed upon HO-1 knockdown via RNA interference. In vivo, CGK012 markedly attenuated iNOS expression in lung tissue and decreased TNF-α levels in bronchoalveolar lavage fluid. These findings underscore the anti-inflammatory potential of CGK012, suggesting its therapeutic promise for conditions characterized by pathological inflammation.

Enhancer regulatory networks globally connect non-coding breast cancer loci to cancer genes

BACKGROUND

Genetic studies have associated thousands of enhancers with breast cancer (BC). However, the vast majority have not been functionally characterized. Thus, it remains unclear how BC-associated enhancers contribute to cancer.

RESULTS

Here, we perform single-cell CRISPRi screens of 3513 regulatory elements associated with breast cancer to measure the impact of these regions on transcriptional phenotypes. Analysis of > 500,000 single-cell transcriptomes in two breast cancer cell lines shows that perturbation of BC-associated enhancers disrupts breast cancer gene programs. We observe BC-associated enhancers that directly or indirectly regulate the expression of cancer genes. We also find one-to-multiple and multiple-to-one network motifs where enhancers indirectly regulate cancer genes. Notably, multiple BC-associated enhancers indirectly regulate TP53. Comparative studies illustrate subtype specific functions between enhancers in ER + and ER - cells. Finally, we develop the pySpade package to facilitate analysis of single-cell enhancer screens.

CONCLUSIONS

Overall, we demonstrate that enhancers form regulatory networks that link cancer genes in the genome, providing a more comprehensive understanding of the contribution of enhancers to breast cancer development.

Epigenetic regulation and post-translational modifications of ferroptosis-related factors in cardiovascular diseases

As an important element of the human body, iron participates in numerous physiological and biochemical reactions. In the past decade, ferroptosis (a form of iron-dependent regulated cell death) has been reported to contribute to the pathogenesis and progression of various diseases. The stability of iron in cardiomyocytes is crucial for the maintenance of normal physiological cardiac activity. Ferroptosis has been detected in many cardiovascular diseases (CVDs), including coronary heart disease, myocardial ischemia-reperfusion injury, heart failure, and chemotherapy-induced myocardial damage. In cardiomyocytes, epigenetic regulation and post-translational modifications regulate the expression of ferroptosis-related factors, maintain iron homeostasis, and participate in the progression of CVDs. Currently, there is no detailed mechanism to explain the relationship between epigenetic regulation and ferroptosis in CVDs. In this review, we provide an initial summary of the core mechanisms of ferroptosis in cardiomyocytes, with first focus on the epigenetic regulation and expression of ferroptosis-related factors in the context of common cardiovascular diseases. We anticipate that the new insights into the pathogenesis of CVDs provided here will inspire the development of clinical interventions to specifically target the active sites of these factors, reducing the harmfulness of ferroptosis to human health.

Gut microbiota derived metabolite trimethylamine N-oxide influences prostate cancer progression via the p38/HMOX1 pathway

BACKGROUND

Prostate cancer was the fourth most diagnosed cancer worldwide in 2022. Radical treatments and androgen deprivation therapy benefit newly diagnosed patients but impact quality of life, often leading to castration-resistant prostate cancer. Short-term dietary changes significantly affect the gut microbiota, which differs markedly between prostate cancer patients and healthy individuals, impacting both cancer progression and treatment response. A high-choline diet increases the risk of fatal prostate cancer, potentially mediated by the conversion of choline to the trimethylamine N-oxide (TMAO) by the gut microbiota.

METHODS

The CCK8 assay was employed to investigate whether TMAO affects the proliferation ability of prostate cancer cells and to determine the appropriate drug concentration. Subsequently, CCK8 time gradients, colony formation assays, and EdU assays measured TMAO's influence on cell proliferation. Wound healing and transwell migration assays evaluated TMAO's effect on cell migration. RNA-seq analysis was performed to explore the mechanisms by which TMAO influences the proliferation and migration of prostate cancer cells. qPCR and Western blotting were utilized to validate the expression of related mRNA or proteins. Finally, we performed in vivo experiments to evaluate the effect of a high choline diet on the growth of subcutaneous tumors and lung metastases in mice.

RESULTS

Our study found that TMAO enhances the proliferation and migration of prostate cancer cells by upregulating HMOX1 via activation of the MAPK signaling pathway, specifically p38 MAPK. In mouse subcutaneous tumor and lung metastatic tumor experiments, the high-choline diet increased prostate cancer cell proliferation and migration, resulting in significantly greater tumor volume and number of metastases than controls.

CONCLUSION

This study is the first to demonstrate the role of the gut microbiota-derived metabolite TMAO in prostate cancer. TMAO promotes the proliferation and migration of prostate cancer cells by activating the p38 pathway and increasing HMOX1 expression. Reducing choline intake through dietary intervention may delay the onset and progression of prostate cancer, presenting significant clinical application value.

Heme oxygenase 1 inhibitor discovery and formulation into nanostructured lipid carriers as potent and selective treatment against triple negative metastatic breast cancer

Heme oxygenase-1 (HO-1) has been identified as a potential new target in anticancer therapy, being overexpressed in different tumors and crucial for cell proliferation. Advances in the development of specific HO-1 inhibitors should support the understanding of controlling HO-1 activity as antitumoral strategies, opening the path for future therapeutic applications. In the present study, small series of new HO-1 inhibitors were synthesized by joining a butylimidazolic pharmacophore together with a hydrophobic moiety spaced by a 2-oxybenzamide central linker. The most active and selective HO-1 inhibitor, VP 21-04, 2-(4-(1H-imidazol-1-yl)butoxy)-N-benzyl-5-iodobenzamide (7b) was identified. This ligand showed strong cytotoxic activity against melanoma and breast cancer cell lines. Encapsulation of VP 21-04 in nanostructured lipid carriers (NLC 21-04) was performed to exploit its therapeutic potential by passive-targeting delivery ameliorating water-solubility and toxicity. Interestingly, NLC 21-04 showed a marked antiproliferative effect in both cancer cell lines, and an improved safety profile with a wider therapeutic window when compared to the free drug. Finally, NLC 21-04 showed a marked tumor growth reduction while being safe in an in ovo tumor model, highlighting the therapeutic potential of the developed nanoparticles against triple negative metastatic breast cancer.

The multi-target mechanism of action of Selaginella doederleinii Hieron in the treatment of nasopharyngeal carcinoma: a network pharmacology and multi-omics analysis

Nasopharyngeal carcinoma (NPC) presents significant treatment challenges due to its complex etiology and late-stage diagnosis. The traditional Chinese medicine Selaginella doederleinii Hieron (S. doederleinii) has shown potentiality in NPC treatment due to its multi-target, multi-pathway anti-cancer mechanisms. First, we identified NPC related target genes from databases like GeneCards, OMIM, and DisGeNET, and performed WGCNA analysis on the GSE53819 dataset to identify several important gene modules related to NPC. Active components and their targets in S. doederleinii were screened from the TCMSP and other databases, identifying 32 overlapping genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that these genes are primarily involved in critical biological processes like protein phosphorylation and cell cycle regulation. A protein-protein interaction network was constructed, and cytoHubba identified six key genes (BCL2, MAPK14, ABCB1, PLK1, ATM, HMOX1). Kaplan-Meier analysis and immune infiltration analysis further showed that these key genes are closely related to the prognosis and immune microenvironment of NPC patients. Single-cell RNA sequencing analysis revealed the expression distribution of key genes across different immune cell types and explored their roles in the differentiation process of malignant cells through pseudotime trajectory analysis. Molecular docking and dynamics simulation results indicated that the Berberine-MAPK14 and Matairesinol-PLK1 complexes have high binding affinity and stability. Binding free energy calculations confirmed the stability of these complexes. Based on our comprehensive multi-level analysis, the active components of S. doederleinii may play a significant role in the treatment of NPC through multi-pathway and multi-target synergistic effects.

The C-X-C Motif Chemokine Ligand 5, Which Exerts an Antioxidant Role by Inducing HO-1 Expression, Is C-X-C Motif Chemokine Receptor 2-Dependent in Human Prostate Stroma and Cancer Cells

While the C-X-C motif chemokine ligand 5 (CXCL5) is recognized as an inflammatory mediator and a potent attractant for immune cells, its functions within the human prostate remain unclear. This study explored the expression, functions, and regulatory mechanisms of CXCL5 in prostate stroma and cancer cells. CXCL5 secreted from prostate cancer cells enhanced neutrophil migration. CXCL5 induced cell proliferation and invasion of prostate cancer cells in vitro and tumorigenesis in a xenograft animal model. C-X-C motif chemokine receptor 2 (CXCR2) has been identified on the surface of prostate fibroblasts and cancer cells. The supernatant of LNCaP cells or CXCL5 overexpression enhanced the migration and contraction of prostate myofibroblast WPMY-1 cells; however, pretreatment with SB225002, a CXCR2 inhibitor, can reverse these effects. CXCL5 evinces antioxidant properties by upregulating heme oxygenase-1 (HO-1) to counteract H2O2-induced reactive oxygen species (ROS) in a CXCR2-dependent manner in WPMY-1 and prostate cancer cells. Our findings illustrate that CXCL5, through HO-1, plays a role in antioxidation, and determine that the CXCL5/CXCR2/HO-1 pathway facilitates antioxidative communication between fibroblasts and cancer cells in the prostate. Therefore, targeting the CXCL5/CXCR2 signaling pathway could provide a new strategy for managing oxidative stress within the prostate.

miR-328-3p suppresses hepatocellular carcinoma progression by regulating HMOX1 expression

INTRODUCTION

Most oncogenic genes contribute to cancer progression, but their role and regulatory mechanisms are not yet fully understood in hepatocellular carcinoma (HCC). This study aimed to explore the role of miR-328-3p and the regulatory relationship between miR-328-3p and HMOX1 in HCC.

METHODS

We utilized Cox and LASSO regression to identify a panel of oncogenic genes associated with hepatocellular carcinoma (HCC) progression within the TCGA-LIHC cohort and the GSE104580 dataset. The expression levels of the hub gene, HMOX1, were assessed in HCC cell lines using qPCR. The functional roles of miR-328-3p and HMOX1 were evaluated through a series of in vitro assays, including CCK-8 for proliferation, colony formation, wound healing, and Transwell assays for migration and invasion. The direct interaction between miR-328-3p and HMOX1 was explored using a luciferase reporter assay, Western blot (WB) for protein expression analysis, and functional assays to determine the impact on cell proliferation and migration.

RESULTS

Eight candidate genes (BIRC5, TNSF4, SPP1, HMOX1, ADM, RBP2, IGF1, and LECT2) were screen out. The hub gene HMOX1 among had high expression level in HCC cell lines. High HMOX1 expressing cell line had significantly increased proliferation and migration capacities. Moreover, HMOX1 was identified as a target of miR-328-3p, which regulated the HMOX1 expression in qPCR and WB assays. High miR-328-3p expressing HCC cell had diminished capacities for proliferation and migration. However, concurrent upregulation of HMOX1 expression resulted in enhanced proliferative and migratory abilities in these cells.

CONCLUSION

Our study has advanced our understanding of the roles of miR-328-3p and HMOX1 in HCC, demonstrating the inhibitory effect of miR-328-3p on the oncogenic activity of HMOX1. Hence, these results revealed the function of miR-328-3p and a novel mechanistic pathway for HCC and suggested the potential therapeutic targeting of miR-328-3p and HMOX1 for HCC intervention strategies.

Evaluation of the anticancer effects exerted by 5-fluorouracil and heme oxygenase-1 inhibitor hybrids in HTC116 colorectal cancer cells

Colon cancer remains a clinical challenge in industrialised countries. Its treatment with 5-Flurouracil (5-FU) develops many side effects and resistance. Thus, several strategies have been undertaken so far, including the use of drug cocktails and polypharmacology. Heme oxygenase-1 (HO-1) is an emerging molecular target in the treatment of various cancers. We recently demonstrated that a combination of HO-1 inhibitors with 5-FU and the corresponding hybrids SI1/17, SI1/20, and SI1/22, possessed anticancer activity against prostate and lung cancer cells. In this work, we evaluated these hybrids in a model of colon cancer and found that SI1/22 and the respective combo have greater potency than 5-FU. Particularly, compounds inhibit HO-1 activity in cell lysates, increase ROS and the expression of HO-1, SOD, and Nrf2. Moreover, we observed a decrease of pro-caspase and an increase in cleaved PARP-1 and p62, suggesting apoptotic and autophagic cell death and potential application of these drugs as anticancer agents.

Comparison of Microalgae Nannochloropsis oceanica and Chlorococcum amblystomatis Lipid Extracts Effects on UVA-Induced Changes in Human Skin Fibroblasts Proteome

Lipid extracts from the microalgae Nannochloropsis oceanica and Chlorococcum amblystomatis have great potential to prevent ultraviolet A (UVA)-induced metabolic disorders. Therefore, the aim of this study has been to analyze their cytoprotective effect, focused on maintaining intracellular redox balance and inflammation in UVA-irradiated skin fibroblasts, at the proteome level. The above lipid extracts reversed the suppression of the antioxidant response caused by UVA radiation, which was more visible in the case of C. amblystomatis. Modulations of interactions between heme oxygenase-1 and matrix metalloproteinase 1/Parkinson's disease protein 7/transcript1-α/β, as well as thioredoxin and migration inhibitory factor/Parkinson's disease protein 7/calnexin/ATPase p97, created key molecular signaling underlying their cytoprotective actions. Moreover, they reduced pro-inflammatory processes in the control group but they also showed the potential to regulate the cellular inflammatory response by changing inflammasome signaling associated with the changes in the caspase-1 interaction area, including heat shock proteins HSP90, HSPA8, and vimentin. Therefore, lipid extracts from N. oceanica and C. amblystomatis protect skin fibroblast metabolism from UVA-induced damage by restoring the redox balance and regulating inflammatory signaling pathways. Thus, those extracts have proven to have great potential to be used in cosmetic or cosmeceutical products to protect the skin against the effects of solar radiation. However, the possibility of their use requires the evaluation of their effects at the skin level in in vivo and clinical studies.

Heme catabolism and heme oxygenase-1-expressing myeloid cells in pathophysiology

Although the pathological significance of myeloid cell heterogeneity is still poorly understood, new evidence indicates that distinct macrophage subsets are characterized by specific metabolic programs that influence disease onset and progression. Within this scenario, distinct subsets of macrophages, endowed with high rates of heme catabolism by the stress-responsive enzyme heme oxygenase-1 (HO-1), play critical roles in physiologic and pathological conditions. Of relevance, the substrates of HO-1 activity are the heme groups that derive from cellular catabolism and are converted into carbon monoxide (CO), biliverdin and Fe2+, which together elicit anti-apoptotic, anti-inflammatory activities and control oxidative damage. While high levels of expression of HO-1 enzyme by specialized macrophage populations (erythrophagocytes) guarantee the physiological disposal of senescent red blood cells (i.e. erythrocateresis), the action of HO-1 takes on pathological significance in various diseases, and abnormal CO metabolism has been observed in cancer, hematological diseases, hypertension, heart failure, inflammation, sepsis, neurodegeneration. Modulation of heme catabolism and CO production is therefore a feasible therapeutic opportunity in various diseases. In this review we discuss the role of HO-1 in different pathological contexts (i.e. cancer, infections, cardiovascular, immune-mediated and neurodegenerative diseases) and highlight new therapeutic perspectives on the modulation of the enzymatic activity of HO-1.

Divergent iron regulatory states contribute to heterogeneity in breast cancer aggressiveness

Contact with dense collagen I (Col1) can induce collective invasion of triple negative breast cancer (TNBC) cells and transcriptional signatures linked to poor patient prognosis. However, this response is heterogeneous and not well understood. Using phenotype-guided sequencing analysis of invasive vs. noninvasive subpopulations, we show that these two phenotypes represent opposite sides of the iron response protein 1 (IRP1)-mediated response to cytoplasmic labile iron pool (cLIP) levels. Invasive cells upregulate iron uptake and utilization machinery characteristic of a low cLIP response, which includes contractility regulating genes that drive migration. Non-invasive cells upregulate iron sequestration machinery characteristic of a high cLIP response, which is accompanied by upregulation of actin sequestration genes. These divergent IRP1 responses result from Col1-induced transient expression of heme oxygenase I (HO-1), which cleaves heme and releases iron. These findings lend insight into the emerging theory that heme and iron fluxes regulate TNBC aggressiveness.

Network pharmacology study and in vitro experimental validation of Xiaojianzhong decoction against gastric cancer

BACKGROUND

Cancer is one of the most serious threats to human health worldwide. Conventional treatments such as surgery and chemotherapy are associated with some drawbacks. In recent years, traditional Chinese medicine treatment has been increasingly advocated by patients and attracted attention from clinicians, and has become an indispensable part of the comprehensive treatment for gastric cancer.

AIM

To investigate the mechanism of Xiaojianzhong decoction (XJZ) in the treatment of gastric cancer (GC) by utilizing network pharmacology and experimental validation, so as to provide a theoretical basis for later experimental research.

METHODS

We analyzed the mechanism and targets of XJZ in the treatment of GC through network pharmacology and bioinformatics. Subsequently, we verified the impact of XJZ treatment on the proliferative ability of GC cells through CCK-8, apoptosis, cell cycle, and clone formation assays. Additionally, we performed Western blot analysis and real-time quantitative PCR to assess the protein and mRNA expression of the core proteins.

RESULTS

XJZ mainly regulates IL6, PTGS2, CCL2, MMP9, MMP2, HMOX1, and other target genes and pathways in cancer to treat GC. The inhibition of cell viability, the increase of apoptosis, the blockage of the cell cycle at the G0/G1 phase, and the inhibition of the ability of cell clone formation were observed in AGS and HGC-27 cells after XJZ treatment. In addition, XJZ induced a decrease in the mRNA expression of IL6, PTGS2, MMP9, MMP2, and CCL2, and an increase in the mRNA expression of HOMX1. XJZ significantly inhibited the expression of IL6, PTGS2, MMP9, MMP2, and CCL2 proteins and promoted the expression of the heme oxygenase-1 protein.

CONCLUSION

XJZ exerts therapeutic effects against GC through multiple components, multiple targets, and multiple pathways. Our findings provide a new idea and scientific basis for further research on the molecular mechanisms underlying the therapeutic effects of XJZ in the treatment of GC.

Antioxidant genes in cancer and metabolic diseases: Focusing on Nrf2, Sestrin, and heme oxygenase 1

Reactive oxygen species are involved in the pathogenesis of cancers and metabolic diseases, including diabetes, obesity, and fatty liver disease. Thus, inhibiting the generation of free radicals is a promising strategy to control the onset of metabolic diseases and cancer progression. Various synthetic drugs and natural product-derived compounds that exhibit antioxidant activity have been reported to have a protective effect against a range of metabolic diseases and cancer. This review highlights the development and aggravation of cancer and metabolic diseases due to the imbalance between pro-oxidants and endogenous antioxidant molecules. In addition, we discuss the function of proteins that regulate the production of reactive oxygen species as a strategy to treat metabolic diseases. In particular, we summarize the role of proteins such as nuclear factor-like 2, Sestrin, and heme oxygenase-1, which regulate the expression of various antioxidant genes in metabolic diseases and cancer. We have included recent literature to discuss the latest research on identifying novel signals of antioxidant genes that can control metabolic diseases and cancer.

Ethanol extract of Vanilla planifolia stems reduces PAK6 expression and induces cell death in glioblastoma cells

Glioblastoma multiforme (GBM) is a malignant tumour with a poor prognosis. Therefore, potential treatment strategies and novel therapeutic targets have gained increased attention. Our data showed that the ethanol extract of Vanilla planifolia stem (VAS) significantly decreased the viability and the colony formation of GBM cells. Moreover, VAS induced the cleavage of MAP1LC3, a marker of autophagy. Further RNA-seq and bioinformatic analysis revealed 4248 differentially expressed genes (DEGs) between VAS-treated GBM cells and the control cells. Protein-protein interactions between DEGs with fold changes less than -3 and more than 5 were further analysed, and we found that 16 and 9 hub DEGs, respectively, were correlated with other DEGs. Further qPCR experiments confirmed that 14 hub DEGs was significantly downregulated and 9 hub DEGs was significantly upregulated. In addition, another significantly downregulated DEG, p21-activated kinase 6 (PAK6), was correlated with the overall survival of GBM patients. Further validation experiments confirmed that VAS significantly reduced the mRNA and protein expression of PAK6, which led to the abolition of cell viability and colony formation. These findings demonstrated that VAS reduced cell viability, suppressed colony formation and induced autophagy and revealed PAK6 and other DEGs as potential therapeutic targets for GBM treatment.

Heme Oxygenase-1 and Prostate Cancer: Function, Regulation, and Implication in Cancer Therapy

Prostate cancer (PC) is a significant cause of mortality in men worldwide, hence the need for a comprehensive understanding of the molecular mechanisms underlying its progression and resistance to treatment. Heme oxygenase-1 (HO-1), an inducible enzyme involved in heme catabolism, has emerged as a critical player in cancer biology, including PC. This review explores the multifaceted role of HO-1 in PC, encompassing its function, regulation, and implications in cancer therapy. HO-1 influences cell proliferation, anti-apoptotic pathways, angiogenesis, and the tumor microenvironment, thereby influencing tumor growth and metastasis. HO-1 has also been associated with therapy resistance, affecting response to standard treatments. Moreover, HO-1 plays a significant role in immune modulation, affecting the tumor immune microenvironment and potentially influencing therapy outcomes. Understanding the intricate balance of HO-1 in PC is vital for developing effective therapeutic strategies. This review further explores the potential of targeting HO-1 as a therapeutic approach, highlighting challenges and opportunities. Additionally, clinical implications are discussed, focusing on the prognostic value of HO-1 expression and the development of novel combined therapies to augment PC sensitivity to standard treatment strategies. Ultimately, unraveling the complexities of HO-1 in PC biology will provide critical insights into personalized treatment approaches for PC patients.

Targeting heme degradation pathway augments prostate cancer cell sensitivity to docetaxel-induced apoptosis and attenuates migration

Introduction

Chemotherapy, notably docetaxel (Doc), stands as the primary treatment for castration-resistant prostate cancer (CRPC). However, its efficacy is hindered by side effects and chemoresistance. Hypoxia in prostate cancer (PC) correlates with chemoresistance to Doc-induced apoptosis via Heme Oxygenase-1 (HO-1) modulation, a key enzyme in heme metabolism. This study investigated targeting heme degradation pathway via HO-1 inhibition to potentiate the therapeutic efficacy of Doc in PC.

Methods

Utilizing diverse PC cell lines, we evaluated HO-1 inhibition alone and with Doc on viability, apoptosis, migration, and epithelial- to- mesenchymal transition (EMT) markers and elucidated the underlying mechanisms.

Results

HO-1 inhibition significantly reduced PC cell viability under hypoxic and normoxic conditions, enhancing Doc-induced apoptosis through interconnected mechanisms, including elevated reactive oxygen species (ROS) levels, glutathione cycle disruption, and modulation of Signal Transducer and Activator of Transcription 1 (STAT1) pathway. The interplay between STAT1 and HO-1 suggests its reliance on HO-1 activation. Additionally, a decrease in cell migration and downregulation of EMT markers (vimentin and snail) were observed, indicating attenuation of mesenchymal phenotype.

Discussion

In conclusion, the combination of HO-1 inhibition with Doc holds promise for improving therapeutic outcomes and advancing clinical management in PC.

Translational insights into the hormetic potential of carbon dioxide: from physiological mechanisms to innovative adjunct therapeutic potential for cancer

Background

Carbon dioxide (CO2), traditionally viewed as a mere byproduct of cellular respiration, plays a multifaceted role in human physiology beyond simple elimination through respiration. CO2 may regulate the tumor microenvironment by significantly affecting the release of oxygen (O2) to tissues through the Bohr effect and by modulating blood pH and vasodilation. Previous studies suggest hypercapnia (elevated CO2 levels) might trigger optimized cellular mechanisms with potential therapeutic benefits. The role of CO2 in cellular stress conditions within tumor environments and its impact on O2 utilization offers a new investigative area in oncology.

Objectives

This study aims to explore CO2's role in the tumor environment, particularly how its physiological properties and adaptive responses can influence therapeutic strategies.

Methods

By applying a structured translational approach using the Work Breakdown Structure method, the study divided the analysis into six interconnected work packages to comprehensively analyze the interactions between carbon dioxide and the tumor microenvironment. Methods included systematic literature reviews, data analyses, data integration for identifying critical success factors and exploring extracellular environment modulation. The research used SMART criteria for assessing innovation and the applicability of results.

Results

The research revealed that the human body's adaptability to hypercapnic conditions could potentially inform innovative strategies for manipulating the tumor microenvironment. This could enhance O2 utilization efficiency and manage adaptive responses to cellular stress. The study proposed that carbon dioxide's hormetic potential could induce beneficial responses in the tumor microenvironment, prompting clinical protocols for experimental validation. The research underscored the importance of pH regulation, emphasizing CO2 and carbonic acid's role in modulating metabolic and signaling pathways related to cancer.

Conclusion

The study underscores CO2 as vital to our physiology and suggests potential therapeutic uses within the tumor microenvironment. pH modulation and cellular oxygenation optimization via CO2 manipulation could offer innovative strategies to enhance existing cancer therapies. These findings encourage further exploration of CO2's therapeutic potential. Future research should focus on experimental validation and exploration of clinical applications, emphasizing the need for interdisciplinary and collaborative approaches to tackle current challenges in cancer treatment.

The effect of baseline O2 conditions on the response of prostate cancer cells to hypoxia

The transcriptional response to hypoxia is largely regulated by the hypoxia-inducible factors (HIFs), which induce the expression of genes involved in glycolysis, angiogenesis, proliferation, and migration. Virtually all cell culture-based hypoxia experiments have used near-atmospheric (18% O2) oxygen levels as the baseline for comparison with hypoxia. However, this is hyperoxic compared with mammalian tissue microenvironments, where oxygen levels range from 2% to 9% O2 (physioxia). Thus, these experiments actually compare hyperoxia to hypoxia. To determine how the baseline O2 level affects the subsequent response to hypoxia, we cultured PC-3 prostate cancer cells in either 18% or 5% O2 for 2 wk before exposing them to hypoxia (∼1.1% pericellular O2) for 12-48 h. RNA-seq revealed that the transcriptional response to hypoxia was dependent on the baseline O2 level. Cells grown in 18% O2 before hypoxia exposure showed an enhanced induction of HIF targets, particularly genes involved in glucose metabolism, compared with cells grown in physioxia before hypoxia. Consistent with this, hypoxia significantly increased glucose consumption and metabolic activity only in cells previously cultured in 18% O2, but not in cells preadapted to 5% O2. Transcriptomic analyses also indicated effects on cell proliferation and motility, which were followed up by functional assays. Although unaffected by hypoxia, both proliferation and migration rates were greater in cells cultured in 5% O2 versus 18% O2. We conclude that an inappropriately hyperoxic starting condition affects the transcriptional and metabolic responses of PC-3 cells to hypoxia, which may compromise experiments on cancer metabolism in vitro.NEW & NOTEWORTHY Although human cell culture models have been instrumental to our understanding of the mechanisms involved in the cellular response to hypoxia, in virtually all experiments, cells are routinely cultured in near-atmospheric (∼18% O2) oxygen levels, which are hyperoxic relative to physiological conditions in vivo. Here, we show for the first time that cells cultured in physiological O2 levels (5% O2) respond differently to subsequent hypoxia than cells grown at 18%.

LHFPL2 Serves as a Potential Biomarker for M2 Polarization of Macrophages in Renal Cell Carcinoma

Renal cell carcinoma (RCC) is one of the most common malignant tumors of the kidney, presenting significant challenges for clinical diagnosis and treatment. Macrophages play crucial roles in RCC, promoting tumor progression and warranting further investigation. Previous studies have identified LHFPL2 as a transmembrane protein associated with reproduction, but its relationship with tumors or macrophages has not been discussed. This study utilized transcriptomic sequencing data from 609 KIRC patients in the TCGA database and single-cell sequencing data from 34,326 renal carcinoma cells for subsequent analysis. We comprehensively evaluated the expression of LHFPL2 and its relationship with clinical features, tumor prognosis, immune infiltration, and mutations. Additionally, we further assessed the correlation between LHFPL2 and macrophage M2 polarization using single-cell data and explored its potential as a cancer therapeutic target through molecular docking. The results demonstrated that LHFPL2 is upregulated in RCC and associated with poor survival rates. In clinical staging, the proportion of malignant and high-metastasis patients was higher in the high-LHFPL2 group than in the low-LHFPL2 group. Furthermore, we found that LHFPL2 influences RCC immune infiltration, with its expression positively correlated with various immune checkpoint and M2-related gene expressions, positively associated with M2 macrophage infiltration, and negatively correlated with activated NK cells. Moreover, LHFPL2 showed specific expression in macrophages, with the high-expression subgroup exhibiting higher M2 polarization, hypoxia, immune evasion, and angiogenesis scores, promoting tumor progression. Finally, we predicted several potential drugs targeting LHFPL2, such as conivaptan and nilotinib. Our analysis elaborately delineates the immune characteristics of LHFPL2 in the tumor microenvironment and its positive correlation with macrophage M2 polarization, providing new insights into tumor immunotherapy. We also propose potential FDA-approved drugs targeting this gene, which should be tested for their binding effects with LHFPL2 in future studies.

Lysosome-Related Genes and RNF19B as Prognostic Markers for Survival and Immunotherapy Efficacy in Hepatocellular Carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) poses a considerable worldwide health concern due to its associated high risk of death. The heterogeneity of HCC poses challenges in developing practical risk stratification tools and identifying prognostic markers for personalized targeted treatments. Recently, lysosomes were shown to be crucial contributors to numerous cellular activities, including tumor initiation and immune response regulation. We aimed to construct a reliable prognostic signature based on lysosome-related genes and determine its association with the immune microenvironment.

METHODS

We comprehensively analyzed lysosome-related genes in HCC to investigate their influence on patient survival and the tumor immune microenvironment. A prognostic signature comprising 14 genes associated with lysosomes was created to estimate the survival outcomes of individuals with HCC. In addition, we verified the prognostic importance of Ring Finger Protein 19B (RNF19B) in patients with HCC through multiplex immunohistochemistry analysis.

RESULTS

Our constructed lysosome-related prediction model could significantly discriminate between HCC patients with good and poor survival outcomes ( P < 0.05). We also found that elevated RNF19B expression was linked to unfavorable prognostic outcomes and showed a connection with specific clinicopathological characteristics. Moreover, it was observed that RNF19B could facilitate the transformation of macrophages into M2-polarized macrophages and showed a significant positive correlation with PD-1 and CTLA-4.

DISCUSSION

In summary, our study proposes that the expression of lysosome-related genes is associated with the immune microenvironment, serving as a predictor for HCC patient survival. Meanwhile, RNF19B was identified as a novel prognostic marker for predicting overall survival and immunotherapy effects in patients with HCC.

HMOX1 regulates ferroptosis via mic14 and its impact on chemotherapy resistance in small-cell lung cancer

This study aimed to investigate the role and molecular mechanism of heme oxygenase-1 (HMOX1) in chemotherapy resistance in small-cell lung cancer (SCLC). Employed bioinformatics, qPCR, and Western Blot to assess HMOX1 levels in SCLC versus normal tissues and its prognostic relevance. CCK-8, flow cytometry, and thiobarbituric acid assays determined HMOX1's impact on SCLC chemosensitivity, ferroptosis markers, lipid peroxidation, and mic14's role in chemoresistance. In the GSE40275 and GSE60052 cohorts, HMOX1 expression was downregulated in SCLC tissues compared to normal tissues. Higher HMOX1 expression was associated with improved prognosis in the Sun Yat-sen University Cancer Hospital cohort and GSE60052 cohort. The RNA and protein levels of HMOX1 were reduced in drug-resistant SCLC cell lines compared to chemosensitive cell lines. Upregulation of HMOX1 increased chemosensitivity and reduced drug resistance in SCLC, while downregulation of HMOX1 decreased chemosensitivity and increased drug resistance. Upregulation of HMOX1 elevated the expression of ferroptosis-related proteins ACSL4, CD71, Transferrin, Ferritin Heavy Chain, and Ferritin Light Chain, while decreasing the expression of GPX4 and xCT. Conversely, downregulation of HMOX1 decreased the expression of ACSL4, CD71, Transferrin, Ferritin Heavy Chain, and Ferritin Light Chain, while increasing the expression of GPX4 and xCT. Upregulation of HMOX1 promoted cellular lipid peroxidation, whereas downregulation of HMOX1 inhibited cellular lipid peroxidation. Upregulation of HMOX1 reduced the RNA level of mic14, while downregulation of HMOX1 increased the RNA level of mic14. mic14 exhibited inhibitory effects on cellular lipid peroxidation in SCLC cells and contributed to reduced chemosensitivity and increased drug resistance in chemoresistant SCLC cell lines. HMOX1 plays a role in ferroptosis by regulating mic14 expression, thereby reversing chemoresistance in SCLC.

Novel Acetamide-Based HO-1 Inhibitor Counteracts Glioblastoma Progression by Interfering with the Hypoxic-Angiogenic Pathway

Glioblastoma multiforme (GBM) represents the deadliest tumor among brain cancers. It is a solid tumor characterized by uncontrolled cell proliferation generating the hypoxic niches in the cancer core. By inducing the transcription of hypoxic inducible factor (HIF), hypoxia triggers many signaling cascades responsible for cancer progression and aggressiveness, including enhanced expression of vascular endothelial growth factor (VEGF) or antioxidant enzymes, such as heme oxygenase-1 (HO-1). The present work aimed to investigate the link between HO-1 expression and the hypoxic microenvironment of GBM by culturing two human glioblastoma cell lines (U87MG and A172) in the presence of a hypoxic mimetic agent, deferoxamine (DFX). By targeting hypoxia-induced HO-1, we have tested the effect of a novel acetamide-based HO-1 inhibitor (VP18/58) on GBM progression. Results have demonstrated that hypoxic conditions induced upregulation and nuclear expression of HO-1 in a cell-dependent manner related to malignant phenotype. Moreover, our data demonstrated that the HO-1 inhibitor counteracted GBM progression by modulating the HIFα/HO-1/VEGF signaling cascade in cancer cells bearing more malignant phenotypes.

Anoikis-related gene signatures predict prognosis of lung adenocarcinoma patients and reveal immune infiltration

Background

Lung adenocarcinoma (LUAD), a type of lung cancer, is one of the most aggressive and deadly malignancies worldwide. Malignant tumor cells exhibit strong anti-anoikis properties to achieve distant metastasis through the circulatory system. However, more research is needed to understand how anoikis is involved in the progression, metastasis and especially the prognosis of LUAD.

Methods

We obtained anoikis-related genes (ARGs) from two websites, Harmonizome and Genecards, and integrated them to select and model the genes associated with LUAD prognosis. In addition, we investigated differences in the immune cell microenvironment and pathways of enrichment analysis between subtypes. We finally constructed a nomogram based on ARGs and used decision curve analysis (DCA) to demonstrate that this model could help clinicians make clinical decisions.

Results

Sixty-four differentially expressed genes (DEGs) were found to be associated with survival, and of these, six were chosen to build a prognostic model. The time-dependent receiver operating characteristic (ROC) curves showed that the model had a satisfactory predictive ability. Enrichment analysis and immune microenvironment analysis revealed that the immune status and drug sensitivity of populations at high and low risk were different. We integrated the clinicopathological features of LUAD with the risk score to build the nomogram. The nomogram was shown to be a good predictor of short- and long-term survival in LUAD patients through DCA analysis.

Conclusions

This new model based on six ARGs and nomograms in our study could help patients with LUAD develop personalized treatment plans.

Unveiling the Genomic Landscape of Intraductal Carcinoma of the Prostate Using Spatial Gene Expression Analysis

Intraductal carcinoma of the prostate (IDCP) has recently attracted increasing interest owing to its unfavorable prognoses. To effectively identify the IDCP-specific gene expression profile, we took a novel approach of characterizing a typical IDCP case using spatial gene expression analysis. A formalin-fixed, paraffin-embedded sample was subjected to Visium CytAssist Spatial Gene Expression analysis. IDCP within invasive prostate cancer sites was recognized as a distinct cluster separate from other invasive cancer clusters. Highly expressed genes defining the IDCP cluster, such as MUC6, MYO16, NPY, and KLK12, reflected the aggressive nature of high-grade prostate cancer. IDCP sites also showed increased hypoxia markers HIF1A, BNIP3L, PDK1, and POGLUT1; decreased fibroblast markers COL1A2, DCN, and LUM; and decreased immune cell markers CCR5 and FCGR3A. Overall, these findings indicate that the hypoxic tumor microenvironment and reduced recruitment of fibroblasts and immune cells, which reflect morphological features of IDCP, may influence the aggressiveness of high-grade prostate cancer.

13-oxyingenol dodecanoate derivatives induce mitophagy and ferroptosis through targeting TMBIM6 as potential anti-NSCLC agents

Ingenol diterpenoids continue to attract the attention for their extensive biological activity and novel structural features. To further explore this type of compound as anti-tumor agent, 13-oxyingenol dodecanoate (13-OD) was prepared by a standard chemical transformation from an Euphorbia kansui extract, and 29 derivatives were synthesized through parent 13-OD. Their inhibition activities against different types of cancer were screened and some derivatives showed superior anti-non-small cell lung cancer (NSCLC) cells cytotoxic potencies than oxaliplatin. In addition, TMBIM6 was identified as a crucial cellular target of 13-OD using ABPP target angling technique, and subsequently was verified by pull down, siRNA interference, BLI and CETSA assays. With modulating the function of TMBIM6 protein by 13-OD and its derivatives, Ca2+ release function was affected, causing mitochondrial Ca2+ overload, depolarisation of membrane potential. Remarkably, 13-OD, B6, A2, and A10-2 induced mitophagy and ferroptosis. In summary, our results reveal that 13-OD, B6, A2, and A10-2 holds great potential in developing anti-tumor agents for targeting TMBIM6.

Fasting and fasting-mimicking conditions in the cancer immunotherapy era

Fasting and fasting-mimicking conditions modulate tumor metabolism and remodel the tumor microenvironment (TME), which could be exploited for the treatment of tumors. A body of evidence demonstrates that fasting and fasting-mimicking conditions can kill cancer cells, or sensitize them to the antitumor activity of standard-of-care drugs while protecting normal cells against their toxic side effects. Pre- and clinical data also suggest that immune responses are involved in these therapeutic effects. Therefore, there is increasing interest in evaluating the impact of fasting-like conditions in the efficacy of antitumor therapies based on the restoration or activation of antitumor immune responses. Here, we review the recent progress in the intersection of fasting-like conditions and current cancer treatments, with an emphasis on cancer immunotherapy.

Pathological significance of heme oxygenase-1 as a potential tumor promoter in heme-induced colorectal carcinogenesis

The significance of the heme-metabolizing enzyme heme oxygenase-1 (HMOX1) in the pathogenesis of colorectal cancer (CRC) has not been fully explored. HMOX1 cytoprotection is imperative to limit oxidative stress. However, its roles in preventing carcinogenesis in response to high levels of heme are not thoroughly understood. This study reviews various mechanisms associated with the paradoxical role of HMOX1, which is advantageous for tumor growth, refractoriness, and survival of cancer cells amid oxidative stress in heme-induced CRC. The alternate role of HMOX1 promotes cell proliferation and metastasis through immune modulation and angiogenesis. Inhibiting HMOX1 has been found to reverse tumor promotion. Thus, HMOX1 acts as a conditional tumor promoter in CRC pathogenesis.

The Interplay between Glioblastoma Cells and Tumor Microenvironment: New Perspectives for Early Diagnosis and Targeted Cancer Therapy

Glioblastoma multiforme (GBM) stands out as the most tremendous brain tumor, constituting 60% of primary brain cancers, accompanied by dismal survival rates. Despite advancements in research, therapeutic options remain limited to chemotherapy and surgery. GBM molecular heterogeneity, the intricate interaction with the tumor microenvironment (TME), and non-selective treatments contribute to the neoplastic relapse. Diagnostic challenges arise from GBM advanced-stage detection, necessitating the exploration of novel biomarkers for early diagnosis. Using data from the literature and a bioinformatic tool, the current manuscript delineates the molecular interplay between human GBM, astrocytes, and myeloid cells, underscoring selected protein pathways belonging to astroglia and myeloid lineage, which can be considered for targeted therapies. Moreover, the pivotal role of extracellular vesicles (EVs) in orchestrating a favorable microenvironment for cancer progression is highlighted, suggesting their utility in identifying biomarkers for GBM early diagnosis.

Putative Molecular Mechanisms Underpinning the Inverse Roles of Mitochondrial Respiration and Heme Function in Lung Cancer and Alzheimer's Disease

Mitochondria are the powerhouse of the cell. Mitochondria serve as the major source of oxidative stress. Impaired mitochondria produce less adenosine triphosphate (ATP) but generate more reactive oxygen species (ROS), which could be a major factor in the oxidative imbalance observed in Alzheimer's disease (AD). Well-balanced mitochondrial respiration is important for the proper functioning of cells and human health. Indeed, recent research has shown that elevated mitochondrial respiration underlies the development and therapy resistance of many types of cancer, whereas diminished mitochondrial respiration is linked to the pathogenesis of AD. Mitochondria govern several activities that are known to be changed in lung cancer, the largest cause of cancer-related mortality worldwide. Because of the significant dependence of lung cancer cells on mitochondrial respiration, numerous studies demonstrated that blocking mitochondrial activity is a potent strategy to treat lung cancer. Heme is a central factor in mitochondrial respiration/oxidative phosphorylation (OXPHOS), and its association with cancer is the subject of increased research in recent years. In neural cells, heme is a key component in mitochondrial respiration and the production of ATP. Here, we review the role of impaired heme metabolism in the etiology of AD. We discuss the numerous mitochondrial effects that may contribute to AD and cancer. In addition to emphasizing the significance of heme in the development of both AD and cancer, this review also identifies some possible biological connections between the development of the two diseases. This review explores shared biological mechanisms (Pin1, Wnt, and p53 signaling) in cancer and AD. In cancer, these mechanisms drive cell proliferation and tumorigenic functions, while in AD, they lead to cell death. Understanding these mechanisms may help advance treatments for both conditions. This review discusses precise information regarding common risk factors, such as aging, obesity, diabetes, and tobacco usage.

Epithelial heme oxygenase-1 enhances colonic tumorigenesis by inhibiting ferroptosis

Colorectal cancer has been linked to chronic colitis and red meat consumption, which can increase colonic iron and heme. Heme oxygenase-1 ( Hmox1 ) metabolizes heme and releases ferrous iron, but its role in colonic tumorigenesis is not well-described. Recent studies suggest that ferroptosis, the iron-dependent form of cell death, protects against colonic tumorigenesis. Ferroptosis culminates in excessive lipid peroxidation that is constrained by the antioxidative glutathione pathway. We observed increased mucosal markers of ferroptosis and glutathione metabolism in the setting of murine and human colitis, as well as murine colonic neoplasia. We obtained similar results in murine and human colonic epithelial organoids exposed to heme and the ferroptosis activator erastin, especially induction of Hmox1 . RNA sequencing of colonic organoids from mice with deletion of intestinal epithelial Hmox1 (Hmox1 ΔIEC ) revealed increased ferroptosis and activated glutathione metabolism after heme exposure. In a colitis-associated cancer model we observed significantly fewer and smaller tumors in Hmox1 ΔIEC mice compared to littermate controls. Transcriptional profiling of Hmox1 ΔIEC tumors and tumor organoids revealed increased ferroptosis and oxidative stress markers in tumor epithelial cells. In total, our findings reveal ferroptosis as an important colitis-associated cancer signature pathway, and Hmox1 as a key regulator in the tumor microenvironment.

Use of Oleuropein and Hydroxytyrosol for Cancer Prevention and Treatment: Considerations about How Bioavailability and Metabolism Impact Their Adoption in Clinical Routine

The fact that the Mediterranean diet could represent a source of natural compounds with cancer-preventive and therapeutic activity has been the object of great interest, especially with regard to the mechanisms of action of polyphenols found in olive oil and olive leaves. Secoiridoid oleuropein (OLE) and its derivative hydroxytyrosol (3,4-dihydroxyphenylethanol, HT) have demonstrated anti-proliferative properties against a variety of tumors and hematological malignancies both in vivo and in vitro, with measurable effects on cellular redox status, metabolism, and transcriptional activity. With this review, we aim to summarize the most up-to-date information on the potential use of OLE and HT for cancer treatment, making important considerations about OLE and HT bioavailability, OLE- and HT-mediated effects on drug metabolism, and OLE and HT dual activity as both pro- and antioxidants, likely hampering their use in clinical routine. Also, we focus on the details available on the effects of nutritionally relevant concentrations of OLE and HT on cell viability, redox homeostasis, and inflammation in order to evaluate if both compounds could be considered cancer-preventive agents or new potential chemotherapy drugs whenever their only source is represented by diet.

Divergent iron-regulatory states contribute to heterogeneity in breast cancer aggressiveness

Primary tumors with similar mutational profiles can progress to vastly different outcomes where transcriptional state, rather than mutational profile, predicts prognosis. A key challenge is to understand how distinct tumor cell states are induced and maintained. In triple negative breast cancer cells, invasive behaviors and aggressive transcriptional signatures linked to poor patient prognosis can emerge in response to contact with collagen type I. Herein, collagen-induced migration heterogeneity within a TNBC cell line was leveraged to identify transcriptional programs associated with invasive versus non-invasive phenotypes and implicate molecular switches. Phenotype-guided sequencing revealed that invasive cells upregulate iron uptake and utilization machinery, anapleurotic TCA cycle genes, actin polymerization promoters, and a distinct signature of Rho GTPase activity and contractility regulating genes. The non-invasive cell state is characterized by actin and iron sequestration modules along with glycolysis gene expression. These unique tumor cell states are evident in patient tumors and predict divergent outcomes for TNBC patients. Glucose tracing confirmed that non-invasive cells are more glycolytic than invasive cells, and functional studies in cell lines and PDO models demonstrated a causal relationship between phenotype and metabolic state. Mechanistically, the OXPHOS dependent invasive state resulted from transient HO-1 upregulation triggered by contact with dense collagen that reduced heme levels and mitochondrial chelatable iron levels. This induced expression of low cytoplasmic iron response genes regulated by ACO1/IRP1. Knockdown or inhibition of HO-1, ACO1/IRP1, MRCK, or OXPHOS abrogated invasion. These findings support an emerging theory that heme and iron flux serve as important regulators of TNBC aggressiveness.

Mechanisms by which silencing long-stranded noncoding RNA KCNQ1OT1 alleviates myocardial ischemia/reperfusion injury (MI/RI)-induced cardiac injury via miR-377-3p/HMOX1

BACKGROUND

The key complication of myocardial infarction therapy is myocardial ischemia/reperfusion injury (MI/RI), and there is no effective treatment. The present study elucidates the mechanism of action of lncRNA KCNQ1OT1 in alleviating MI/RI and provides new perspectives and therapeutic targets for cardiac injury-related diseases.

METHODS

An ischemia/reperfusion (I/R) injury model of human adult cardiac myocytes (HACMs) was constructed, and the expression of KCNQ1OT1 and miR-377-3p was determined by RT‒qPCR. The levels of related proteins were detected by western blot analysis. Cell proliferation was detected by a CCK-8 assay, and cell apoptosis and ROS content were determined by flow cytometry. SOD and MDA expression as well as Fe2+ changes were detected by related analysis kits. The target binding relationships between lncRNA KCNQ1OT1 and miR-377-3p as well as between miR-377-3p and heme oxygenase 1 (HMOX1) were verified by a dual-luciferase reporter gene assay.

RESULTS

Myocardial ischemia‒reperfusion caused oxidative stress in HACMs, resulting in elevated ROS levels, increased Fe2+ levels, decreased cell viability, and increased LDH release (a marker of myocardial injury), and apoptosis. KCNQ1OT1 and HMOX1 were upregulated in I/R-induced myocardial injury, but the level of miR-377-3p was decreased. A dual-luciferase reporter gene assay indicated that lncRNA KCNQ1OT1 targets miR-377-3p and that miR-377-3p targets HMOX1. Inhibition of HMOX1 alleviated miR-377-3p downregulation-induced myocardial injury. Furthermore, lncRNA KCNQ1OT1 promoted the level of HMOX1 by binding to miR-377-3p and aggravated myocardial injury.

CONCLUSION

LncRNA KCNQ1OT1 aggravates ischemia‒reperfusion-induced cardiac injury via miR-377-3P/HMOX1.

Metabolomic profile of neuroendocrine tumors identifies methionine, porphyrin, and tryptophan metabolisms as key dysregulated pathways associated with patient survival

OBJECTIVE

Metabolic profiling is a valuable tool to characterize tumor biology but remains largely unexplored in neuroendocrine tumors (NETs). Our aim was to comprehensively assess the metabolomic profile of NETs and identify novel prognostic biomarkers and dysregulated molecular pathways.

DESIGN AND METHODS

Multiplatform untargeted metabolomic profiling (GC-MS, CE-MS, and LC-MS) was performed in plasma from 77 patients with G1-2 extra-pancreatic NETs enrolled in the AXINET trial (NCT01744249) (study cohort) and from 68 non-cancer individuals (control). The prognostic value of each differential metabolite (n = 155) in NET patients (P < .05) was analyzed by univariate and multivariate analyses adjusted for multiple testing and other confounding factors. Related pathways were explored by Metabolite Set Enrichment Analysis (MSEA) and Metabolite Pathway Analysis (MPA).

RESULTS

Thirty-four metabolites were significantly associated with progression-free survival (PFS) (n = 16) and/or overall survival (OS) (n = 27). Thirteen metabolites remained significant independent prognostic factors in multivariate analysis, 3 of them with a significant impact on both PFS and OS. Unsupervised clustering of these 3 metabolites stratified patients in 3 distinct prognostic groups (1-year PFS of 71.1%, 47.7%, and 15.4% (P = .012); 5-year OS of 69.7%, 32.5%, and 27.7% (P = .003), respectively). The MSEA and MPA of the 13-metablolite signature identified methionine, porphyrin, and tryptophan metabolisms as the 3 most relevant dysregulated pathways associated with the prognosis of NETs.

CONCLUSIONS

We identified a metabolomic signature that improves prognostic stratification of NET patients beyond classical prognostic factors for clinical decisions. The enriched metabolic pathways identified reveal novel tumor vulnerabilities that may foster the development of new therapeutic strategies for these patients.

AhR-STAT3-HO-1/COX-2 signalling pathway may restrict ferroptosis and improve hMSC accumulation and efficacy in mouse liver

BACKGROUND AND PURPOSE

The low efficacy of mesenchymal stem cells (MSCs) has restricted their application in the treatment of liver disease. Emerging evidence suggested that ferroptosis may provoke hepatocyte dysfunction and exacerbate damage to the liver microenvironment. Here, we have investigated the contribution of liver ferroptosis to the elimination and effectiveness of human MSC (hMSC). Furthermore, potential links between liver ferroptosis and aryl hydrocarbon receptors (AhR) were explored.

EXPERIMENTAL APPROACH

Two mouse models, iron supplement-induced hepatic ferroptosis and hepatic ischaemia/reperfusion (I/R) injury, were used to identify effects of ferroptosis on hMSC pharmacokinetics (PK)/pharmacodynamics (PD).

KEY RESULTS

AhR inhibition attenuated hepatic ferroptosis and improved survival of hMSCs. hMSC viability was decreased by iron supplementation or serum from I/R mice. The AhR antagonist CH223191 reversed iron overload and oxidative stress induced by ferroptosis and increased hMSC concentration and efficacy in mouse models. Effects of CH223191 were greater than those of deferoxamine, a conventional ferroptosis inhibitor. Transcriptomic results suggested that the AhR-signal transducer and activator of transcription 3 (STAT3)-haem oxygenase 1/COX-2 signalling pathway is critical to this process. These results were confirmed in a mouse model of hepatic I/R injury. In mice pre-treated with CH223191, hMSC exhibited more potent protective effects, linked to decreased hepatic ferroptosis.

CONCLUSION AND IMPLICATIONS

Our findings showed that ferroptosis was a critical factor in determining the fate of hMSCs. Inhibition of AhR decreased hepatic ferroptosis, thereby increasing survival and therapeutic effects of hMSCs in mouse models of liver disease.

Dysregulation of Peripheral Blood Mononuclear Cells and Immune-Related Proteins during the Early Post-Operative Immune Response in Ovarian Cancer Patients

Surgical treatment is a cornerstone of ovarian cancer (OC) therapy and exerts a substantial influence on the immune system. Immune responses also play a pivotal and intricate role in OC progression. The aim of this study was to investigate the dynamics of immune-related protein expression and the activity of peripheral blood mononuclear cells (PBMCs) in OC patients, both before surgery and during the early postoperative phase. The study cohort comprised 23 OC patients and 20 non-cancer controls. A comprehensive analysis of PBMCs revealed significant pre-operative downregulation in the mRNA expression of multiple immune-related proteins, including interleukins, PD-1, PD-L1, and HO-1. This was followed by further dysregulation during the first 5 post-operative days. Although most serum interleukin concentrations showed only minor changes, a distinct increase in IL-6 and HO-1 levels was observed post-operatively. Reduced metabolic and phagocytic activity and increased production of reactive oxygen species (ROS) were observed on day 1 post-surgery. These findings suggest a shift towards immune tolerance during the early post-operative phase of OC, potentially creating a window for treatment. Further research into post-operative PBMC activity could lead to the development of new or improved treatment strategies for OC.

Enhancer regulatory networks globally connect non-coding breast cancer loci to cancer genes

Genetic studies have associated thousands of enhancers with breast cancer. However, the vast majority have not been functionally characterized. Thus, it remains unclear how variant-associated enhancers contribute to cancer. Here, we perform single-cell CRISPRi screens of 3,512 regulatory elements associated with breast cancer to measure the impact of these regions on transcriptional phenotypes. Analysis of >500,000 single-cell transcriptomes in two breast cancer cell lines shows that perturbation of variant-associated enhancers disrupts breast cancer gene programs. We observe variant-associated enhancers that directly or indirectly regulate the expression of cancer genes. We also find one-to-multiple and multiple-to-one network motifs where enhancers indirectly regulate cancer genes. Notably, multiple variant-associated enhancers indirectly regulate TP53. Comparative studies illustrate sub-type specific functions between enhancers in ER+ and ER- cells. Finally, we developed the pySpade package to facilitate analysis of single-cell enhancer screens. Overall, we demonstrate that enhancers form regulatory networks that link cancer genes in the genome, providing a more comprehensive understanding of the contribution of enhancers to breast cancer development.