RESUMO
The recovery of lithium from spent lithium iron phosphate (LiFePO4) batteries is of great significance to prevent resource depletion and environmental pollution. In this study, through active ingredient separation, selective leaching and stepwise chemical precipitation develop a new method for the selective recovery of lithium from spent LiFePO4 batteries by using sodium persulphate (Na2S2O8) to oxidize LiFePO4 to FePO4. The impact of various variables on the efficiency of lithium leaching was investigated. Moreover, a combination of thermodynamic analysis and characterization techniques such as X-ray diffraction and X-ray photoelectron spectroscopy was employed to elucidate the leaching mechanism. It was found that 98.65% of lithium could be selectively leached in just 35 minutes at 60°C with only 0.2 times excess of Na2S2O8. This high leaching efficiency can be attributed to the stability and lack of structural damage during the oxidation leaching process. The proposed process is economically viable and environmentally friendly, thus showing great potential for the large-scale recycling of spent LiFePO4 batteries.
RESUMO
RNA-binding protein RBM28 (RBM28), as a nucleolar component of spliceosomal small nuclear ribonucleoproteins, is involved in the nucleolar stress response. Whether and how RBM28 regulates tumor progression remains unclear. Here, we report that RBM28 is frequently overexpressed in various types of cancer and that its upregulation is associated with a poor prognosis. Functional and mechanistic assays revealed that RBM28 promotes the survival and growth of cancer cells by interacting with the DNA-binding domain of tumor suppressor p53 to inhibit p53 transcriptional activity. Upon treatment with chemotherapeutic drugs (e.g., adriamycin), RBM28 is translocated from the nucleolus to the nucleoplasm, which is likely mediated via phosphorylation of RBM28 at Ser122 by DNA checkpoint kinases 1 and 2 (Chk1/2), indicating that RBM28 may act as a nucleolar stress sensor in response to DNA damage stress. Our findings not only reveal RBM28 as a potential biomarker and therapeutic target for cancers but also provide mechanistic insights into how cancer cells convert stress signals into a cellular response linking the nucleolus to regulation of the tumor suppressor p53.
Assuntos
Proteínas de Ligação a RNA , Proteína Supressora de Tumor p53 , Linhagem Celular Tumoral , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Humanos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Transcrição Gênica , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
BACKGROUND: Gene editing technology has provided researchers with the ability to modify genome sequences in almost all eukaryotes. Gene-edited cell lines are being used with increasing frequency in both bench research and targeted therapy. However, despite the great importance and universality of gene editing, the efficiency of homology-directed DNA repair (HDR) is too low, and base editors (BEs) cannot accomplish desired indel editing tasks. RESULTS AND DISCUSSION: Our group has improved HDR gene editing technology to indicate DNA variation with an independent selection marker using an HDR strategy, which we named Gene Editing through an Intronic Selection marker (GEIS). GEIS uses a simple process to avoid nonhomologous end joining (NHEJ)-mediated false-positive effects and achieves a DsRed positive rate as high as 87.5% after two rounds of fluorescence-activated cell sorter (FACS) selection without disturbing endogenous gene splicing and expression. We re-examined the correlation of the conversion tract and efficiency, and our data suggest that GEIS has the potential to edit approximately 97% of gene editing targets in human and mouse cells. The results of further comprehensive analysis suggest that the strategy may be useful for introducing multiple DNA variations in cells.
Assuntos
Sistemas CRISPR-Cas , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Edição de Genes/métodos , Íntrons/genética , Proteínas Luminescentes/genética , Sequência de Bases , DNA/genética , DNA/metabolismo , Éxons/genética , Células HEK293 , Humanos , Proteínas Luminescentes/metabolismo , Microscopia de Fluorescência , Mutação , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição RelA/genéticaRESUMO
BACKGROUND: 3-phosphoinositide-dependent protein kinase-1 (PDK1) acts as a master kinase of protein kinase A, G, and C family (AGC) kinase to predominantly govern cell survival, proliferation, and metabolic homeostasis. Although the regulations to PDK1 downstream substrates such as protein kinase B (AKT) and ribosomal protein S6 kinase beta (S6K) have been well established, the upstream regulators of PDK1, especially its degrader, has not been defined yet. METHOD: A clustered regularly interspaced short palindromic repeats (CRISPR)-based E3 ligase screening approach was employed to identify the E3 ubiquitin ligase for degrading PDK1. Western blotting, immunoprecipitation assays and immunofluorescence (IF) staining were performed to detect the interaction or location of PDK1 with speckle-type POZ protein (SPOP). Immunohistochemistry (IHC) staining was used to study the expression of PDK1 and SPOP in prostate cancer tissues. In vivo and in vitro ubiquitination assays were performed to measure the ubiquitination conjugation of PDK1 by SPOP. In vitro kinase assays and mass spectrometry approach were carried out to identify casein kinase 1 (CK1) and glycogen synthase kinase 3 (GSK3)-mediated PDK1 phosphorylation. The biological effects of PDK1 mutations and correlation with SPOP mutations were performed with colony formation, soft agar assays and in vivo xenograft mouse models. RESULTS: We identified that PDK1 underwent SPOP-mediated ubiquitination and subsequent proteasome-dependent degradation. Specifically, SPOP directly bound PDK1 by the consensus degron in a CK1/GSK3ß-mediated phosphorylation dependent manner. Pathologically, prostate cancer patients associated mutations of SPOP impaired PDK1 degradation and thus activated the AKT kinase, resulting in tumor malignancies. Meanwhile, mutations that occurred around or within the PDK1 degron, by either blocking SPOP to bind the degron or inhibiting CK1 or GSK3ß-mediated PDK1 phosphorylation, could markedly evade SPOP-mediated PDK1 degradation, and played potently oncogenic roles via activating the AKT kinase. CONCLUSIONS: Our results not only reveal a physiological regulation of PDK1 by E3 ligase SPOP, but also highlight the oncogenic roles of loss-of-function mutations of SPOP or gain-of-function mutations of PDK1 in tumorigenesis through activating the AKT kinase.
Assuntos
Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Transformação Celular Neoplásica/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Repressoras/metabolismo , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Modelos Animais de Doenças , Quinase 3 da Glicogênio Sintase/metabolismo , Xenoenxertos , Humanos , Camundongos , Modelos Biológicos , Mutação , Proteínas Nucleares/genética , Fosforilação , Ligação Proteica , Proteólise , Proteínas Repressoras/genética , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
Human single-stranded DNA binding protein 1 (hSSB1) plays a critical role in responding to DNA damage and maintaining genome stability. However, the regulation of hSSB1 remains poorly studied. Here, we determined that hSSB1 acetylation at K94 mediated by the acetyltransferase p300 and the deacetylases SIRT4 and HDAC10 impaired its ubiquitin-mediated degradation by proteasomes. Moreover, we demonstrated that the hSSB1-K94R mutant had reduced cell survival in response to DNA damage by radiation or chemotherapy drugs. Furthermore, the p300/CBP inhibitor C646 significantly enhanced the sensitivity of cancer cells to chemotherapy drugs, and a positive correlation between hSSB1 and p300 level was observed in clinical colorectal cancer samples. Acetylation, a novel regulatory modification of hSSB1, is crucial for its function under both physiological and pathological conditions. This finding supports the notion that the combination of chemotherapy drugs with acetylation inhibitors may benefit cancer patients.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Mitocondriais/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Linhagem Celular , Dano ao DNA , Proteínas de Ligação a DNA/química , Histona Desacetilases/metabolismo , Humanos , Lisina/metabolismo , Proteínas Mitocondriais/química , Domínios e Motivos de Interação entre Proteínas , Estabilidade Proteica , Sirtuínas/metabolismo , Ubiquitinação , Fatores de Transcrição de p300-CBP/químicaRESUMO
Single-stranded DNA-binding proteins (SSBs) are essential for maintaining the integrity of the genome in all organisms. All processes related to DNA, such as replication, excision, repair, and recombination, require the participation of SSBs whose oligonucleotide/oligosaccharide-binding (OB)-fold domain is responsible for the interaction with single-stranded DNA (ssDNA). For a long time, the heterotrimeric replication protein A (RPA) complex was believed to be the only nuclear SSB in eukaryotes to participate in ssDNA processing, while mitochondrial SSBs that are conserved with prokaryotic SSBs were shown to be essential for maintaining genome stability in eukaryotic mitochondria. In recent years, two new proteins, hSSB1 and hSSB2 (human SSBs 1/2), were identified and have better sequence similarity to bacterial and archaeal SSBs than RPA. This review summarizes the current understanding of these human SSBs in DNA damage repair and in cell-cycle checkpoint activation following DNA damage, as well as their relationships with cancer.
Assuntos
Proteínas de Ligação a DNA/fisiologia , Instabilidade Genômica/fisiologia , Dano ao DNA , Reparo do DNA , Humanos , Proteína de Replicação A/fisiologiaRESUMO
Microvesicles (MVs) containing proteins, nucleic acid or organelles are shed from the plasma membrane. Although the mechanisms of MV budding are well elucidated, the connection between endosomal trafficking and MV formation remains poorly understood. In this report, RAB22A is revealed to be crucial for EGFR-containing MVs formation by the RAB GTPase family screening. RAB22A recruits TBC1D2B, a GTPase-activating protein (GAP) of RAB7A, to inactivate RAB7A, thus preventing EGFR from being transported to late endosomes and lysosomes. RAB22A also engages SH3BP5L, a guanine-nucleotide exchange factor (GEF) of RAB11A, to activate RAB11A on early endosomes. Consequently, EGFR is recycled to the cell surface and packaged into MVs. Furthermore, EGFR can phosphorylate RAB22A at Tyr136, which in turn promotes EGFR-containing MVs formation. Our findings illustrate that RAB22A acts as a sorter on early endosomes to sort EGFR to recycling endosomes for MV shedding by both activating RAB11A and inactivating RAB7A.
Assuntos
Endossomos , Receptores ErbB , Proteínas rab de Ligação ao GTP , Receptores ErbB/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Endossomos/metabolismo , Humanos , Transporte Proteico , Micropartículas Derivadas de Células/metabolismo , proteínas de unión al GTP Rab7/metabolismo , Células HeLa , Proteínas Ativadoras de GTPase/metabolismo , Lisossomos/metabolismoRESUMO
Cervical cancer is the most common gynecologic cancer, etiologically related to persistent infection of human papillomavirus (HPV). Both the host innate immunity system and the invading HPV have developed sophisticated and effective mechanisms to counteract each other. As a central innate immune sensing signaling adaptor, stimulator of interferon genes (STING) plays a pivotal role in antiviral and antitumor immunity, while viral oncoproteins E7, especially from HPV16/18, are responsible for cell proliferation in cervical cancer, and can inhibit the activity of STING as reported. In this report, we find that activation of STING-TBK1 (TANK-binding kinase 1) promotes the ubiquitin-proteasome degradation of E7 oncoproteins to suppress cervical cancer growth. Mechanistically, TBK1 is able to phosphorylate HPV16/18 E7 oncoproteins at Ser71/Ser78, promoting the ubiquitination and degradation of E7 oncoproteins by E3 ligase HUWE1. Functionally, activated STING inhibits cervical cancer cell proliferation via down-regulating E7 oncoproteins in a TBK1-dependent manner and potentially synergizes with radiation to achieve better effects for antitumor. Furthermore, either genetically or pharmacologically activation of STING-TBK1 suppresses cervical cancer growth in mice, which is independent on its innate immune defense. In conclusion, our findings represent a new layer of the host innate immune defense against oncovirus and provide that activating STING/TBK1 could be a promising strategy to treat patients with HPV-positive cervical cancer.
Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Animais , Camundongos , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo , Neoplasias do Colo do Útero/patologia , Papillomavirus Humano 18/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
We recently revealed that activated STING is secreted into RAB22A-induced extracellular vesicles (R-EVs) and promotes antitumor immunity in cancer cells. Whether mesenchymal stem cell (MSC)-derived R-EVs containing activated STING can be used as a novel antitumor immunotherapy remains unclear, as MSC-derived EVs are promising cell-free therapeutics due to their superior biocompatibility and safety, as well as low immunogenicity. Here, we report that induced pluripotent stem cell (iPSC)-derived MSCs can generate R-EVs with a size and mechanism of formation that are similar to those of R-EVs produced from cancer cells. Furthermore, these MSC-derived R-EVs containing activated STING induced IFNß expression in recipient THP-1 monocytes and antitumor immunity in mice. Our findings reveal that the use of MSC-derived R-EVs containing activated STING is a promising cell-free strategy for antitumor immunity.
Assuntos
Vesículas Extracelulares , Células-Tronco Pluripotentes Induzidas , Proteínas de Membrana , Células-Tronco Mesenquimais , Animais , Células-Tronco Pluripotentes Induzidas/imunologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Humanos , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Proteínas de Membrana/metabolismo , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Interferon beta/metabolismo , Interferon beta/imunologia , Células THP-1 , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/patologia , Neoplasias/metabolismo , Linhagem Celular TumoralRESUMO
Bladder cancer (BC) is one of the most common tumors characterized by a high rate of relapse and a lack of targeted therapy. Here, YEATS domain-containing protein 4 (YEATS4) is an essential gene for BC cell viability using CRISPR-Cas9 library screening is reported, and that HUWE1 is an E3 ligase responsible for YEATS4 ubiquitination and proteasomal degradation by the Protein Stability Regulators Screening Assay. KAT8-mediated acetylation of YEATS4 impaired its interaction with HUWE1 and consequently prevented its ubiquitination and degradation. The protein levels of YEATS4 and KAT8 are positively correlated and high levels of these two proteins are associated with poor overall survival in BC patients. Importantly, suppression of YEATS4 acetylation with the KAT8 inhibitor MG149 decreased YEATS4 acetylation, reduced cell viability, and sensitized BC cells to cisplatin treatment. The findings reveal a critical role of the KAT8/YEATS4 axis in both tumor growth and cisplatin sensitivity in BC cells, potentially generating a novel therapeutic strategy for BC patients.
Assuntos
Cisplatino , Histona Acetiltransferases , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Humanos , Cisplatino/farmacologia , Linhagem Celular Tumoral , Camundongos , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/genética , Animais , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Acetilação/efeitos dos fármacos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genéticaRESUMO
Physiologically, FoxA1 plays a key role in liver differentiation and development, and pathologically exhibits an oncogenic role in prostate and breast cancers. However, its role and upstream regulation in liver tumorigenesis remain unclear. Here, we demonstrate that FoxA1 acts as a tumor suppressor in liver cancer. Using a CRISPR-based kinome screening approach, noncanonical inflammatory kinase IKBKE has been identified to inhibit FoxA1 transcriptional activity. Notably, IKBKE directly binds to and phosphorylates FoxA1 to reduce its complex formation and DNA interaction, leading to elevated hepatocellular malignancies. Nonphosphorylated mimic Foxa1 knock-in mice markedly delay liver tumorigenesis in hydrodynamic transfection murine models, while phospho-mimic Foxa1 knock-in phenocopy Foxa1 knockout mice to exhibit developmental defects and liver inflammation. Notably, Ikbke knockout delays diethylnitrosamine (DEN)-induced mouse liver tumor development. Together, our findings not only reveal FoxA1 as a bona fide substrate and negative nuclear effector of IKBKE in hepatocellular carcinioma (HCC) but also provide a promising strategy to target IKBEK for HCC therapy.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Masculino , Camundongos , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Neoplasias Hepáticas/patologia , Camundongos KnockoutRESUMO
BACKGROUND: Chromobox homolog 4 (CBX4) is a member of the chromobox family of Polycomb group proteins involved in the chromatin remodeling and transcriptional regulation. However, its clinical relevance in hepatocellular carcinoma (HCC) has not yet been explored. METHODS: Immunohistochemistry was used to analyze cytoplasmic expression of CBX4 in 246 HCC specimens. The expression of CBX4 in HCC cell lines and LO2 was detected by Western blot test. Cell cycle and MTT assays were used to determine the changes of cell growth capacity. The expression of downstream genes related to proliferation was detected by Western blot test. RESULTS: The expression of CBX4 was up-regulated in multiple HCC cell lines and clinical samples. Although the CBX4 protein was detectable in both nucleus and cytoplasm in HCC tumor tissues, the high expression of CBX4 in cytoplasm was correlated with the α-fetoprotein level in serum (P = 0.036), tumor size (P = 0.029), pathologic differentiation (P = 0.033), and tumor, node, metastasis classification system stages (P = 0.032). Moreover, HCC patients who had a high level of CBX4 in cytoplasm had a shorter overall survival (P = 0.003) and recurrence-free survival (P = 0.012). Indeed, using HCC cell line, knockdown of CBX4 led to down-regulating proliferating cell nuclear antigen and cyclin E2 as well as up-regulating p16, followed by decreased cell proliferation and impaired cell cycle progression. CONCLUSIONS: The cytoplasmic CBX4 protein may be a useful prognostic biomarker and a potential therapeutic target for HCC.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas do Grupo Polycomb/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Western Blotting , Carcinoma Hepatocelular/mortalidade , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Ligases , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas do Grupo Polycomb/antagonistas & inibidores , Proteínas do Grupo Polycomb/genética , Prognóstico , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/genéticaRESUMO
Dysregulation of transcription is a hallmark of cancer, including bladder cancer (BLCA). CRISPR-Cas9 screening using a lentivirus library with single guide RNAs (sgRNAs) targeting human transcription factors and chromatin modifiers is used to reveal genes critical for the proliferation and survival of BLCA cells. As a result, the nuclear transcription factor Y subunit gamma (NFYC)-37, but not NFYC-50, is observed to promote cell proliferation and tumor growth in BLCA. Mechanistically, NFYC-37 interacts with CBP and SREBP2 to activate mevalonate pathway transcription, promoting cholesterol biosynthesis. However, NFYC-50 recruits more of the arginine methyltransferase CARM1 than NFYC-37 to methylate CBP, which prevents the CBP-SREBP2 interaction and subsequently inhibits the mevalonate pathway. Importantly, statins targeting the mevalonate pathway can suppress NFYC-37-induced cell proliferation and tumor growth, indicating the need for conducting a clinical trial with statins for treating patients with BLCA and high NFYC-37 levels, as most patients with BLCA have high NFYC-37 levels.
Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias da Bexiga Urinária , Humanos , Ácido Mevalônico/metabolismo , RNA Guia de Sistemas CRISPR-Cas , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Fatores de Transcrição/metabolismoRESUMO
Immunotherapies targeting the PD-1/PD-L1 axis have become first-line treatments in multiple cancers. However, only a limited subset of individuals achieves durable benefits because of the elusive mechanisms regulating PD-1/PD-L1. Here, we report that in cells exposed to interferon-γ (IFNγ), KAT8 undergoes phase separation with induced IRF1 and forms biomolecular condensates to upregulate PD-L1. Multivalency from both the specific and promiscuous interactions between IRF1 and KAT8 is required for condensate formation. KAT8-IRF1 condensation promotes IRF1 K78 acetylation and binding to the CD247 (PD-L1) promoter and further enriches the transcription apparatus to promote transcription of PD-L1 mRNA. Based on the mechanism of KAT8-IRF1 condensate formation, we identified the 2142-R8 blocking peptide, which disrupts KAT8-IRF1 condensate formation and consequently inhibits PD-L1 expression and enhances antitumor immunity in vitro and in vivo. Our findings reveal a key role of KAT8-IRF1 condensates in PD-L1 regulation and provide a competitive peptide to enhance antitumor immune responses.
Assuntos
Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Humanos , Linhagem Celular Tumoral , Antígeno B7-H1/genética , Receptor de Morte Celular Programada 1/metabolismo , Interferon gama/genética , Interferon gama/farmacologia , Imunoterapia , Histona Acetiltransferases/metabolismo , Fator Regulador 1 de Interferon/genética , Fator Regulador 1 de Interferon/metabolismoRESUMO
Osteosarcoma is a highly aggressive cancer and lacks effective therapeutic targets. We found that L3MBTL2 acts as a tumor suppressor by transcriptionally repressing IFIT2 in osteosarcoma. L3MBTL2 recruits the components of Polycomb repressive complex 1.6 to form condensates via both Pho-binding pockets and polybasic regions within carboxyl-terminal intrinsically disordered regions; the L3MBTL2-induced condensates are required for its tumor suppression. Multi-monoubiquitination of L3MBTL2 by UBE2O results in its proteasomal degradation, and the UBE2O/L3MBTL2 axis was crucial for osteosarcoma growth. There is a reverse correlation between L3MBTL2 and UBE2O in osteosarcoma tissues, and higher UBE2O and lower L3MBTL2 are associated with poorer prognosis in osteosarcoma. Pharmacological blockage of UBE2O by arsenic trioxide can enhance L3MBTL2-induced condensates and consequently suppress osteosarcoma growth. Our findings unveil a crucial biological function of L3MBTL2-induced condensates in mediating tumor suppression, proposing the UBE2O-L3MBTL2 axis as a potential cancer therapeutic target in osteosarcoma.
Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , UbiquitinaçãoRESUMO
A recently identified protein, FAN1 (FANCD2-associated nuclease 1, previously known as KIAA1018), is a novel nuclease associated with monoubiquitinated FANCD2 that is required for cellular resistance against DNA interstrand crosslinking (ICL) agents. The mechanisms of FAN1 regulation have not yet been explored. Here, we provide evidence that FAN1 is degraded during mitotic exit, suggesting that FAN1 may be a mitotic substrate of the anaphase-promoting cyclosome complex (APC/C). Indeed, Cdh1, but not Cdc20, was capable of regulating the protein level of FAN1 through the KEN box and the D-box. Moreover, the up- and down-regulation of FAN1 affected the progression to mitotic exit. Collectively, these data suggest that FAN1 may be a new mitotic substrate of APC/CCdh1 that plays a key role during mitotic exit.
Assuntos
Caderinas/metabolismo , Exodesoxirribonucleases/metabolismo , Mitose , Complexos Ubiquitina-Proteína Ligase/metabolismo , Ciclossomo-Complexo Promotor de Anáfase , Antígenos CD , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Caderinas/genética , Proteínas Cdc20 , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Endodesoxirribonucleases , Exodesoxirribonucleases/genética , Células HEK293 , Humanos , Enzimas Multifuncionais , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Complexos Ubiquitina-Proteína Ligase/genéticaRESUMO
INTRODUCTION: Bladder cancer (BC) is one of the most common malignant cancers, with poor prognosis and high incidence. Cisplatin is the standard chemotherapy for muscle invasive bladder cancer; however, chemotherapy resistance remains a major challenge. Moreover, oncogenic signalling and the specific mechanisms underlying cisplatin resistance in BC remain largely unclear METHODS: In this study, RT-PCR, Western blot, immunofluorescence, and immunohistochemistry were used to measure gene and protein expression. Colony formation assay and flow cytometry were performed to evaluate the proliferation of BC cells. Gene set enrichment analysis was performed to identify the function in which ZBTB11 was involved. Luciferase and chromatin immunoprecipitation experiments were performed to determine the transcriptional regulation mechanism of ZBTB11. The effects of ZBTB11 on the malignant phenotypes of BC cells were examined in vitro and in vivo RESULTS: The results showed that ZBTB11 was remarkably upregulated in BC tissues, which was associated with poor prognosis in patients with BC. Furthermore, we found that knockdown of ZBTB11 remarkably inhibited the proliferation and tumorigenesis of BC cells by inducing apoptosis. Mechanistically, the knockdown of ZBTB11 transcriptionally inhibited DDX1 to suppress R-loop clearance, resulting in DNA damage in BC cells. Importantly, the ZBTB11/DDX1 axis is required for the chemotherapy resistance of BC cells to cisplatin CONCLUSION: Our findings not only reveal an underlying mechanism by which the ZBTB11/DDX1 axis promotes the tumorigenesis of BC but also provide a potential target for a combination strategy of cisplatin-based chemotherapy for BC.
Assuntos
MicroRNAs , Neoplasias da Bexiga Urinária , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Estruturas R-Loop , Linhagem Celular Tumoral , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proliferação de Células/genética , RNA Helicases DEAD-box/metabolismoRESUMO
Zinc finger protein 154 (ZNF154) is hypermethylated at the promoter in many epithelial-derived solid tumors. However, its methylation status and function in esophageal squamous carcinoma (ESCC) are poorly understood. We found that the ZNF154 promoter is hypermethylated in ESCC and portends poor prognosis. In addition, ZNF154 functions as a tumor suppressor gene (TSG) in ESCC, and is downregulated by promoter hypermethylation. We established a targeted demethylation strategy based on CRISPR/dCas9 technology and found that the hypermethylation of ZNF154 promoter repressed ZNF154 induction, which in turn promoted the proliferation and migration of ESCC cells in vitro and in vivo. Finally, high-throughput CUT&Tag analysis, GEPIA software and qPCR were used to revealed the role of ZNF154 as a transcription factor to upregulate the expression of ESCC-associated tumor suppressor genes. Taken together, hypermethylation of the ZNF154 promoter plays an important role in the development of ESCC, and epigenetic editing is a promising tool for inhibiting ESCC cells with aberrant DNA methylation.
Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Neoplasias Epiteliais e Glandulares , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Metilação de DNA/genética , Desmetilação , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Epiteliais e Glandulares/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Transcription dysregulation is a salient characteristic of bladder cancer (BC), but no appropriate therapeutic target for it has been established. Here, we found that heterogeneous downregulation of histone H4 transcription factor (HINFP) was associated with senescence in BC tissues and that lower HINFP expression could predict an unfavorable outcome in BC patients. Knockout of HINFP transcriptionally inhibited H1F0 and H1FX to trigger DNA damage, consequently inducing cell senescence to repress the proliferation and growth of BC cells. However, the senescence-associated secretory phenotype, characterized by increases in MMP1/3, enhances the invasion and metastasis of non-senescent BC cells. Histone deacetylase inhibitors (HDACis) could efficiently eliminate the senescent cells induced by HINFP knockout to suppress the invasion and metastasis of BC cells. Our study suggests that HDACis, widely used in multiple cancer types in a clinical context, may also benefit BC patients with metastases induced by cell senescence.