Emerging role of necroptosis, pyroptosis, and ferroptosis in breast cancer: New dawn for overcoming therapy resistance

How has the field of immunogenic cell death in breast cancer evolved and impacted clinical practice over the past eleven years?

This study elucidates the research landscape of immunogenic cell death (ICD) in breast cancer through a bibliometric analysis of 457 Web of Science articles. Contributions from China and the USA are particularly prominent, with notable international collaborations. Core journals such as Biomaterials published influential studies, while researchers like Huang Y made impactful contributions. High-frequency keyword analysis identified key research hotspots, including immunotherapy, the tumor microenvironment, and nanomedicine. The integration of chemotherapy with immunotherapy and the identification of key proteins have driven recent advancements. Fundamental research on immunotherapy, photodynamic therapy (PDT), and triple-negative breast cancer (TNBC) points to future trends and potential breakthroughs. This study offers a strategic overview of ICD in breast cancer, providing insights into clinical practice and guiding future research in the field.

Orphan Nuclear Receptor 4A1 (NR4A1) and NR4A2are Endogenous Regulators of CD71 and TheirLigands Induce Ferroptosis in Breast Cancer

Ferroptosis is an iron-dependent cell death pathway that involves multiple genes including the transferrin receptor (TFRC/CD71), glutathione peroxidase 4 (GPX4) and SLC7A11. This study is based on the hypothesis that orphan nuclear receptor 4A1 (NR4A1) and NR4A2 maintain low levels of ferroptosis in triple negative breast cancer (TNBC) cells and that bis-indole derived (CDIM) compounds act as NR4A1/2 ligands that induce ferroptosis by enhancing CD71 expression. 1,1-Bis(3'-indolyl)-1-(3,5-disubstitutedphenyl)methane (DIM-3,5) analogs were investigated for their cytotoxicity and effects on NR4A1 and NR4A2 regulated genes and induction of ferroptosis by cytotoxicity, western blot and RT-PCR. Several assays also determined enhanced lipoperoxidation, reactive oxygen species and malondialdehyde formation in TNBC cells. Knockdown of NR4A1, NR4A2, Sp1 and Sp4 was carried out by RNA interference. Molecular mechanisms of NR4A1/2-mediated regulation of CD71 expression were determined using CD71-luciferase promoter constructs, overexpression of Sp1 and chromatin immunoprecipitation (ChIP) assays. Initial studies show that DIM-3,5 act as an inverse NR4A1/NR4A2 agonist that downregulated the pro-oncogenic responses/gene products regulated by both receptors in TNBC cells. DIM-3,5 analogs also induced ROS, malondialdehyde and lipoperoxide formation in TNBC cells and this was accompanied by indicators of ferroptosis that include decreased expression of GPX4 and SLC7A11 and induction of CD71. Induction of CD71, an important biomarker of ferroptosis was observed after treatment of TNBC cells with DIM-3,5 analogs, knockdown of NR4A1, NR4A2, Sp1 or Sp4 demonstrating that induction of CD71 was coregulated by both receptors. Moreover, both promoter and ChIP analysis indicated that NR4A1 and NR4A2 acted as ligand-dependent cofactors of Sp1/4-mediated expression of CD71 in TNBC cells. CD71, a key biomarker of ferroptosis is an NR4A1/2/Sp regulated gene that can be directly targeted by DIM-3,5 inverse NR4A1/2 agonists to induce ferroptosis in TNBC cells.

Caspase-independent cell death in lung cancer: from mechanisms to clinical applications

Caspase-independent cell death (CICD) has recently become a very important mechanism in lung cancer, in particular, to overcome a critical failure in apoptotic cell death that is common to disease progression and treatment failures. The pathways involved in CICD span from necroptosis, ferroptosis, mitochondrial dysfunction, and autophagy-mediated cell death. Its potential therapeutic applications have been recently highlighted. Glutathione peroxidase 4 (GPX4) inhibition-driven ferroptosis has overcome drug resistance in non-small cell lung cancer (NSCLC). In addition, necroptosis involving RIPK1 and RIPK3 causes tumor cell death and modulation of immune responses in the tumor microenvironment (TME). Mitochondrial pathways are critical for CICD through modulation of metabolic and redox homeostasis. Ferroptosis is amplified by mitochondrial reactive oxygen species (ROS) and lipid peroxidation in lung cancer cells, and mitochondrial depolarization induces oxidative stress and leads to cell death. In addition, mitochondria-mediated autophagy, or mitophagy, results in the clearance of damaged organelles under stress conditions, while this function is also linked to CICD when dysregulated. The role of cell death through autophagy regulated by ATG proteins and PI3K/AKT/mTOR pathway is dual: to suppress tumor and to sensitize cells to therapy. A promising approach to enhancing therapeutic outcomes involves targeting mechanisms of CICD, including inducing ferroptosis by SLC7A11 inhibition, modulating mitochondrial ROS generation, or combining inhibition of autophagy with chemotherapy. Here, we review the molecular underpinnings of CICD, particularly on mitochondrial pathways and their potential to transform lung cancer treatment.

Unraveling cell death mechanisms in traumatic brain injury: dynamic roles of ferroptosis and necroptosis

Traumatic brain injury (TBI) remains a major cause of mortality and long-term disability worldwide, with ferroptosis and necroptosis emerging as key drivers of secondary neuronal damage. Ferroptosis, characterized by iron-dependent lipid peroxidation and mitochondrial dysfunction, exacerbates oxidative stress and neuronal cell death. In parallel, necroptosis, mediated by receptor-interacting protein kinases (RIPK1 and RIPK3), amplifies inflammation through membrane rupture and the release of cellular components. Mitochondrial dynamics, involving fission and fusion processes, play a dual role in regulating these pathways. While mitochondrial fusion preserves cellular integrity and reduces oxidative stress, excessive mitochondrial fission driven by dynamin-related protein 1 (DRP1) accelerates necroptotic signaling and neuronal injury. This intricate interplay between ferroptosis, necroptosis, and mitochondrial dynamics highlights potential therapeutic targets. Modulating these pathways through tailored interventions could reduce neuronal damage, mitigate neuroinflammation, and improve functional outcomes in TBI patients. Advancing our understanding of these mechanisms is essential for developing precision therapies that address the complex pathology of traumatic brain injury.

Dual-Gating Strategy: Ultrasound Activation of TRPV2 Channels and Borate-Glass-Induced Calcium Overload for Tumor Suppression

Effective and precise treatment of breast cancer, particularly with bone metastasis, remains a significant challenge. Here, a dual-gating strategy combining locally delivered borate glass (BG) and ultrasound (US) is developed for the precise and effective inhibition of breast cancer by targeting transient receptor potential vanilloid 2 (TRPV2). The results demonstrate that after local delivery of BG to the solid tumor, US effectively triggers calcium overload by activating the overexpressed TRPV2 channels, leading to mitochondrial autophagy and apoptosis in breast cancer cells, thereby inhibiting tumor growth with high precision. These effects are validated in subcutaneous, orthotopic, and TRPV2-overexpressing breast cancer mouse models. In the bone metastasis model, BG combined with US treatment simultaneously suppresses tumor growth and promotes bone regeneration. Overall, this dual-gating strategy offers a safe and efficient approach for the precise treatment of cancers with high TRPV2 expression and provides new insights into the design and clinical translation of calcium-overload-based cancer therapies.

Absence of Cysteine and Iron Chelation Induces Ferroptosis in Triple-Negative Breast Cancer Cells

Background

Ferroptosis is a recently studied form of programmed cell death characterized by lipid peroxides accumulation in the cells. This process occurs when a cell's antioxidant capacity is disturbed resulting in the inability of the cell to detoxify the toxic peroxides. Two major components that regulate ferroptosis are cysteine and iron.

Objective

This study aimed to determine the effect of cysteine deficiency and iron chelation on triple-negative breast cancer (TNBC) ferroptosis in a lipid-enriched microenvironment.

Design

The study has a laboratory-based experimental design. This study used the MDA-MB-231 cell line in various in vitro cell culture systems to investigate the research question.

Methods

For the first part of the study, we subjected MDA-MB-231 cells to grow in cysteine-absent adipocyte-conditioned media. In the second half, we treated MDA-MB-231 cells with iron chelator, deferoxamine. BODIPY imaging and western blot were carried out to observe ferroptosis in the cells under the 2 conditions.

Results

The results showed that cysteine absence in the conditioned media was able to reduce the formation of lipid droplets, which increased the greater access to free fatty acids to undergo oxidation, therefore inducing ferroptosis. On the contrary, cells when treated with deferoxamine along with erastin (ferroptosis-inducing drug), showed an increase in cell iron content was observed, later inducing ferroptosis.

Conclusion

Our results show an alternative function of cysteine and deferoxamine, one regulating lipid droplets and the other inducing ferroptosis, although an inhibitor of the same, respectively.

Ferroptosis: A new way to intervene in the game between Mycobacterium tuberculosis and macrophages

Mycobacterium tuberculosis (Mtb), the main pathogen responsible for the high mortality and morbidity of tuberculosis (TB) worldwide, primarily targets and invades macrophages. Infected macrophages activate a series of immune mechanisms to clear Mtb, however, Mtb evades host immune surveillance through subtle immune escape strategies to create a microenvironment conducive to its own proliferation, growth, and dissemination, while inducing immune cell death. The course of TB is strongly correlated with the form of cell death, including apoptosis, pyroptosis, and necrosis. Recent studies have revealed that ferroptosis, a novel type of programmed cell death characterized by iron-dependent lipid peroxidation, is closely linked to the regulatory mechanisms of TB. The central role of ferroptosis in the pathologic process of TB is increasingly becoming a focal point for exploring new therapeutic targets in this field. This paper will delve into the dynamic game between Mtb and host immune cells, especially the role of ferroptosis in the pathogenesis of TB. At the same time, this paper will analyze the regulatory pathways of ferroptosis and provide unique insights and innovative perspectives for TB therapeutic strategies based on the ferroptosis mechanism. This study not only expands the theoretical basis of TB treatment, but also points out the direction of future drug development, providing new possibilities for overcoming this global health problem.

TRIB3 knockdown increases the sensitivity of clear cell renal cell carcinoma to sunitinib by inducing ferroptosis

Sunitinib resistance presents a significant challenge in the treatment of clear cell renal cell carcinoma (ccRCC). The role of TRIB3, a newly identified oncogene, in tumor drug resistance has been widely studied. However, the mechanism by which TRIB3 contributes to sunitinib resistance in ccRCC has not been previously explored. This study aimed to investigate the mechanism through which TRIB3 regulates ferroptosis to increase the susceptibility of ccRCC to sunitinib treatment. Bioinformatics analysis and experimental validation revealed that TRIB3 is significantly upregulated in ccRCC tissues and is associated with poor prognosis. Knockdown of TRIB3 using siRNA transfection inhibited the proliferation and migration of ccRCC cells and induced ferroptosis. Following sunitinib treatment, TRIB3 knockdown increased cell sensitivity to sunitinib, enhanced the suppressive impact of sunitinib, and augmented sunitinib-induced ferroptosis. This study demonstrated that TRIB3 knockdown induces ferroptosis by targeting the SLC7A11/GPX4 pathway and enhances therapeutic efficacy of sunitinib for ccRCC, providing new insights and potential strategies to overcome the challenge of sunitinib resistance in ccRCC.

Excavating regulated cell death signatures to predict prognosis, tumor microenvironment and therapeutic response in HR+/HER2- breast cancer

Regulated cell death (RCD) has been documented to have great potentials for discovering novel biomarkers and therapeutic targets in malignancies. But its role and clinical value in HR+/HER2- breast cancer, the most common subtype of breast cancer, are obscure. In this study, we comprehensively explored 12 types of RCD patterns and found extensive mutations and dysregulations of RCD genes in HR+/HER2- breast cancer. A prognostic RCD scoring system (CDScore) based on six critical genes (LEF1, SLC7A11, SFRP1, IGFBP6, CXCL2, STXBP1) was constructed, in which a high CDScore predicts poor prognosis. The expressions and prognostic value of LEF1 and SFRP1were also validated in our tissue microarrays. The nomogram established basing on CDScore, age and TNM stage performed satisfactory in predicting overall survival, with an area under the ROC curve of 0.89, 0.82 and 0.8 in predicting 1-year, 3-year and 5-year overall survival rates, respectively. Furthermore, CDScore was identified to be correlated with tumor microenvironments and immune checkpoints by excavation of bulk and single-cell sequencing data. Patients in CDScore high group might be resistant to standard chemotherapy and target therapy. Our results underlined the potential effects and importance of RCD in HR+/HER2- breast cancer and provided novel biomarkers and therapeutic targets for HR+/HER2- breast cancer patients.