Cell Death & Disease最新文献

The treatment of non-small cell lung cancer (NSCLC) patients has significantly improved with recent therapeutic strategies; however, many patients still do not benefit from them. As a result, new treatment approaches are urgently needed. In this study, we evaluated the antitumor efficacy of co-targeting G9a and DNMT1 enzymes and its potential as a cancer drug sensitizer. We observed co-expression and overexpression of G9a and DNMT1 in NSCLC, which were associated with poor prognosis. Co-targeting G9a/DNMT1 with the drug CM-272 reduced proliferation and induced cell death in a panel of human and murine NSCLC cell lines. Additionally, the transcriptomes of these cells were reprogrammed to become highly responsive to chemotherapy (cisplatin), targeted therapy (trametinib), and epigenetic therapy (vorinostat). In vivo, CM-272 reduced tumor volume in human and murine cell-derived cancer models, and this effect was synergistically enhanced by cisplatin. The expression of SCARA5 and AOX1 was induced by CM-272, and both proteins were found to be essential for the antiproliferative response, as gene silencing decreased cytotoxicity. Furthermore, the expression of SCARA5 and AOX1 was positively correlated with each other and inversely correlated with G9a and DNMT1 expression in NSCLC patients. SCARA5 and AOX1 DNA promoters were hypermethylated in NSCLC, and SCARA5 methylation was identified as an epigenetic biomarker in tumors and liquid biopsies from NSCLC patients. Thus, we demonstrate that co-targeting G9a/DNMT1 is a promising strategy to enhance the efficacy of cancer drugs, and SCARA5 methylation could serve as a non-invasive biomarker to monitor tumor progression.

OMA1 is an ATP-independent zinc metalloprotease essential for maintaining mitochondrial homeostasis and plays a vital role in tumorigenesis. Depending on the type of cancer, a decrease in OMA1 expression has been linked to a varying prognosis for patients. The role of OMA1 in human osteosarcoma (OS), one of the most prevalent malignant bone tumors, remains elusive. Here, we observed elevated OMA1 expression in OS tumor tissues from four patients with advanced OS. Knockout of OMA1 in OS cells significantly reduces OS tumor weight and size, and lung metastatic nodules in BALB/c nude mice. Immunohistochemistry analysis showed a significant decrease in Ki67 and an increase in Cleaved-caspase 3 in OMA1 knockout tumor samples. Mechanistically, we found that OMA1 deficiency increases the levels of PINK1 and Parkin and consequently induces excessive mitophagy, leading to increased apoptosis and reduced cell proliferation and invasion in OS cells. Specifically, OMA1 deficiency reduces the amount of cytosolic p53 and p53-associated cytosolic Parkin but increases mitochondrial p53, which may lead to enhanced apoptosis. Regarding the effect on cell proliferation and invasion, loss of OMA1 reduces mitochondrial ROS levels and increases cytosolic glycogen synthase kinase 3β (GSK3β) levels, thereby increasing interaction between GSK3β and β-catenin and then reducing cytosolic and nuclear β-catenin. This contributes to reduced cell proliferation and migration in OMA1-deficient cells. Moreover, we found that ciclopirox (CPX), an antifungal drug, induces OMA1 self-cleavage and L-OMA1 degradation in cultured OS cells. CPX also reduces tumor development of control OS cells but not OMA1-deficient OS cells in mice. These findings strongly support the important role of OMA1 in OS tumorigenesis and suggest that OMA1 may be a valuable prognostic marker and a promising therapeutic target for OS.

The mucosal epithelium of the head and neck region (including the oral cavity, nasal cavity, pharynx, nasopharynx, and larynx) is the primary site exposed to tobacco smoke, and its presence of nicotinic acetylcholine receptors (nAChRs) has been observed in the mucosal epithelial cells of this area. It remains unclear whether HNSC cells can migrate and invade through nAChR signaling. A model of HNSC cells exposed to nicotine is established. Cell proliferation following nicotine exposure is assessed using the CCK-8 assay, while migration and invasion are evaluated through wound healing and Transwell assays. The effects of CHRNA5 knockdown and overexpression are also investigated. Immunofluorescence staining is used to analyze CHRNA5 expression and localization, and clonogenic assays are performed to measure colony proliferation after CHRNA5 knockdown and overexpression. The interaction between CHRNA5 and CES1 is examined using molecular docking, co-immunoprecipitation, and immunofluorescence. Differentially expressed genes are subjected to pathway enrichment analysis, and MEK/ERK protein expression and phosphorylation are validated via western blot. Tumor formation assays are performed in nude mice using sh-CHRNA5 Cal27 cells, followed by western blot and immunohistochemical staining. Additionally, laryngeal and hypopharyngeal cancer tissues are analyzed through immunohistochemistry. Nicotine significantly enhanced the proliferation, migration, and invasion capabilities of head and neck tumor cells, including Cal27, Fadu, HN6, and Tu686 cells, through the expression of CHRNA5. Knockdown of CHRNA5 can reduce cell migration, invasion, and proliferation, whereas nicotine exposure can reverse this trend. Additionally, the mRNA and protein expression of CES1 decreases with the knockdown of CHRNA5, indicating a regulatory relationship between the two. Transcriptomics revealed that the knockdown of CHRNA5 is associated with the MEK/ERK signaling pathway. Further cellular- and tissue-level evidence confirmed that the levels of p-MEK/MEK, p-ERK/ERK, and CES1 decreased following knockdown of CHRNA5, a trend that nicotine can reverse. Nicotine promotes the proliferation, migration, and invasion of HNSC by upregulating CHRNA5 expression. Knockdown of CHRNA5 reduces these effects, which can be reversed by nicotine. Nicotine exposure activates CHRNA5, regulating CES1 expression via the MEK/ERK pathway, contributing to the recurrence and metastasis of head and neck squamous carcinoma.

Skeletal muscle mesenchymal progenitors (MPs) play a critical role in supporting muscle regeneration. However, under pathological conditions, they contribute to intramuscular adipose tissue accumulation, involved in muscle diseases, including muscular dystrophy and sarcopenia, age-related muscular atrophy. How MP fate is determined in these different contexts remains unelucidated. Here, we report that Ror2, a non-canonical Wnt signaling receptor, is selectively expressed in MPs and regulates their pathological features in a differential ligand-dependent manner. We identified Wnt11 and Wnt5b as ligands of Ror2. In vitro, Wnt11 inhibited MP senescence, which is required for normal muscle regeneration, and Wnt5b promoted MP proliferation. We further found that both Wnts are abundant in degenerating muscle and synergistically stimulate Ror2, leading to unwanted MP proliferation and eventually intramuscular adipose tissue accumulation. These findings provide evidence that Ror2-mediated signaling elicited by differential Wnts plays a critical role in determining the pathological fate of MPs.

Gallbladder cancer (GBC) presents as an aggressive malignancy with poor patient outcome. Like other epithelial cancers, the mechanisms of GBC cancer progression remain vague and efforts in finding targeted therapies fall below expectations. This study combined proteomic analysis of formalin-fixed paraffin-embedded (FFPE) GBC samples, functional and molecular characterization of potential oncogenes and identification of potential therapeutic strategies for GBC. We identified Carcinoembryonic Antigen-related Cell Adhesion Molecule 6 (CEACAM6) as one of the significantly most upregulated proteins in GBC. CEACAM6 overexpression has been observed in other cancer entities but the molecular function remains unclear. Our functional analyses in vitro and in vivo mouse models revealed that CEACAM6 supported the initial steps of cancer progression and metastasis by decreasing cell adhesion and promoting migration and invasion of GBC cells. Conversely, CEACAM6 knockdown abolished GBC aggressiveness by increasing cell adhesion while reducing cell migration, cell proliferation, and colony formation. BirA-BioID followed by mass-spectrometry revealed Integrin Beta-1 (ITGB1) and Protein Kinase C Delta (PRKCD) as direct molecular and functional partners of CEACAM6 supporting GBC cell migration. ERK and AKT signaling and their downstream target genes were regulated by CEACAM6 and thus the treatment with AKT inhibitor capivasertib or ERK inhibitor ulixertinib mitigated the CEACAM6-induced migration. These findings demonstrate that CEACAM6 is crucially involved in gallbladder cancer progression by promoting migration and inhibiting cell adhesion through ERK and AKT signaling providing specific options for treatment of CEACAM6-positive cancers.

Alzheimer's disease (AD) affects millions of people worldwide and represents the most prevalent form of dementia. Treatment strategies aiming to interfere with the formation of amyloid β (Aβ) plaques and neurofibrillary tangles (NFTs), the two major AD hallmarks, have shown modest or no effect. Recent evidence suggests that ferroptosis, a type of programmed cell death caused by iron accumulation and lipid peroxidation, contributes to AD pathogenesis. The existing link between ferroptosis and AD has been largely based on cell culture and animal studies, while evidence from human brain tissue is limited. Here we evaluate if Aβ is associated with ferroptosis pathways in post-mortem human brain tissue and whether ferroptosis inhibition could attenuate Aβ-related effects in human brain organoids. Performing positive pixel density scoring on immunohistochemically stained post-mortem Brodmann Area 17 sections revealed that the progression of AD pathology was accompanied by decreased expression of nuclear receptor co-activator 4 and glutathione peroxidase 4 in the grey matter. Differentiating between white and grey matter, allowed for a more precise understanding of the disease's impact on different brain regions. In addition, ferroptosis inhibition prevented Aβ pathology, decreased lipid peroxidation and restored iron storage in human AD iPSCs-derived brain cortical organoids at day 50 of differentiation. Differential gene expression analysis of RNAseq of AD organoids compared to isogenic controls indicated activation of the ferroptotic pathway. This was also supported by results from untargeted proteomic analysis revealing significant changes between AD and isogenic brain organoids. Determining the causality between the development of Aβ plaques and the deregulation of molecular pathways involved in ferroptosis is crucial for developing potential therapeutic interventions.

N⁶-Methyladenosine (m⁶A) is an evolutionarily highly conserved epigenetic modification that affects eukaryotic RNAs, especially mRNAs, and m⁶A modification is commonly linked to tumor proliferation, progression, and therapeutic resistance by participating in RNA metabolism. Autophagy is an intracellular degradation and recycling biological process by which cells remove damaged organelles, protein aggregates, and other intracellular wastes, and release nutrients to maintain cell survival when energy is scarce. Recent studies have shown that m⁶A modification plays a critical role in the regulation of autophagy, affecting the initiation of autophagy, the formation and assembly of autophagosomes, and lysosomal function by regulating critical regulatory molecules involved in the process of autophagy. Moreover, autophagy can also affect the expression of the three types of regulators related to m⁶A, which in turn affects the levels of their target genes via m⁶A modification. Thus, m⁶A modification and autophagy form a sophisticated regulatory network through mutual regulation, which plays an important role in tumor progression and therapeutic resistance. In this manuscript, we reviewed the effects of m⁶A modification on autophagy as well as the effects of autophagy on m⁶A modification and the roles of the m⁶A-autophagy axis in tumor progression and therapy resistance. Additionally, we summarized the value and application prospects of key molecules in the m⁶A-autophagy axis in tumor diagnosis and therapy.

Cancer stem cells (CSCs) are a group of specially programmed tumor cells that possess the characteristics of perpetual cell renewal, increased invasiveness, and often, drug resistance. Hence, eliminating CSCs is a major challenge for cancer treatment. Understanding the cellular programs that maintain CSCs, and identifying the critical regulators for such programs, are major undertakings in both basic and translational cancer research. Recently, we have reported that RAB4A is a major regulator of epithelial-to-mesenchymal transition (EMT) and it does so mainly through regulating the activation of RAC1 GTPase. In the current study, we have delineated a new signaling circuitry through which RAB4A transmits its control of cancer stemness. Using in vitro and in vivo studies, we show that RAB4A, as the upstream regulator, relays signal stepwise to NUMB, NOTCH1, RAC1, and then SOX2 to control the self-renewal property of multiple cancer cells of diverse tissue origins. Knockdown of NUMB, or overexpression of NICD (the active fragment NOTCH1) or SOX2, rescued the in vitro sphere-forming and in vivo tumor-forming abilities that were lost upon RAB4A knockdown. Furthermore, we discovered that the chain of control is mostly through transcriptional regulation at every step of the pathway. The discovery of the novel signaling axis of RAB4A-NUMB-NOTCH-SOX2 opens the path for further expansion of the signaling chain and for the identification of new regulators and interacting proteins important for CSC functions, which can be explored to develop new and effective therapies.

Excessive DNA damage triggers various types of programmed cell death (PCD), yet the regulatory mechanism of DNA damage-induced cell death is not fully understood. Here, we report that PANoptosis, a coordinated PCD pathway, including pyroptosis, apoptosis and necroptosis, is activated by DNA damage. The Z-DNA binding protein 1 (ZBP1) is the apical sensor of PANoptosis and essential for PANoptosome assembly in response to DNA damage. We find endogenous retroviruses (ERVs) are activated by DNA damage and act as ligands for ZBP1 to trigger PANoptosis. By using ZBP1 knock-out and knock-in mice disrupting ZBP1 nucleic acid-binding activity, we demonstrate that ZBP1-mediated PANoptosis contributes to the toxic effects of chemotherapeutic drugs, which is dependent on ZBP1 nucleic acid-binding activity. We found that ZBP1 expression is downregulated in tumor tissue. Furthermore, in colorectal cancer patients, dsRNA is induced by chemotherapy and sensed by ZBP1 in normal colonic tissues, suggesting ZBP1-mediated PANoptosis is activated by chemotherapy in normal tissues. Our findings indicate that ZBP1-mediated PANoptosis is activated by DNA damage and contributes to the toxic side effects of DNA-damage-based chemotherapy. These data suggest that ZBP1 could be a promising therapeutic target to alleviate chemotherapy-related side effects.