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1.
Immunity ; 53(6): 1168-1181.e7, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33326766

RESUMO

Viruses have evolved multiple strategies to evade elimination by the immune system. Here we examined the contribution of host long noncoding RNAs (lncRNAs) in viral immune evasion. By functional screening of lncRNAs whose expression decreased upon viral infection of macrophages, we identified a lncRNA (lncRNA-GM, Gene Symbol: AK189470.1) that promoted type I interferon (IFN-I) production and inhibited viral replication. Deficiency of lncRNA-GM in mice increased susceptibility to viral infection and impaired IFN-I production. Mechanistically, lncRNA-GM bound to glutathione S-transferase M1 (GSTM1) and blocked GSTM1 interaction with the kinase TBK1, reducing GSTM1-mediated S-glutathionylation of TBK1. Decreased S-glutathionylation enhanced TBK1 activity and downstream production of antiviral mediators. Viral infection reprogrammed intracellular glutathione metabolism and furthermore, an oxidized glutathione mimetic could inhibit TBK1 activity and promote viral replication. Our findings reveal regulation of TBK1 by S-glutathionylation and provide insight into the viral mediated metabolic changes that impact innate immunity and viral evasion.


Assuntos
Glutationa/metabolismo , Evasão da Resposta Imune , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Glutationa Transferase/metabolismo , Humanos , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , RNA Longo não Codificante/genética , Transdução de Sinais , Viroses/genética , Viroses/imunologia , Viroses/metabolismo , Replicação Viral
2.
Nutr Cancer ; 76(3): 279-295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38226887

RESUMO

This study aims to build a prognostic model based on lactic acid metabolism-related genes (LMRGs) to predict survival outcomes and tumor microenvironment status of Hepatocellular carcinoma (HCC) patients. The model was used to calculate riskscores of clinical samples. Survival analysis and Cox regression analysis were conducted to verify the independence and reliability of the riskscore to determine its clinical significance in prognosis evaluation of HCC. Additionally, we conducted a comprehensive analysis of tumor mutation burden (TMB), immune cell infiltration, and gene set molecular function in the high- and low-risk groups. We obtained 134 LMRGs mainly involved in cellular calcium homeostasis and calcium signaling pathways. The LMRGs in the risk assessment model included PFKFB4, SLC16A3, ADRA2B, SLC22A1, QRFPR, and PROK1. This study discovered much shorter overall survival and median survival time of patients with higher riskscores when compared to those with lower riskscores. It was indicated that for independent prediction of patients' prognosis, the riskscore had a significant clinical value. A remarkable difference was also found regarding TMB between the two groups. Finally, cell experiments demonstrated that the knockout of PFKFB4 and SLC16A3 genes suppressed lactate. Our research demonstrated that the riskscore, established based on LMRGs, is a promising biomarker.


Assuntos
Carcinoma Hepatocelular , Hormônios Gastrointestinais , Neoplasias Hepáticas , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina , Humanos , Ácido Láctico , Carcinoma Hepatocelular/genética , Microambiente Tumoral/genética , Reprodutibilidade dos Testes , Neoplasias Hepáticas/genética , Prognóstico , Receptores Acoplados a Proteínas G , Fosfofrutoquinase-2
3.
Curr Ther Res Clin Exp ; 98: 100700, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123033

RESUMO

Background: Antisense transcript of the B-cell translocation gene 3 (ASBEL) is a highly conserved antisense non-coding RNA (ncRNA) and participates in a variety of biological processes. However, the ASBEL expression status in pancreatic ductal adenocarcinoma (PDAC) and its correlation with BTG3 expression and tumor cell progression were not completely clear. Objective: We conducted cell experiments and animal experiments to confirm that ASBEL plays a crucial role in the tumorigenesis of PDAC by targeting BTG3. Methods: ASBEL regulation in PDAC tumorigenesis was evaluated using Western blotting, quantitative polymerase chain reaction, Cell Counting Kit-8 assay, flow cytometry, and cell transfection. We also evaluated the expression of ASBEL and BTG3 in tumor tissues and cells using Western blotting and quantitative real-time polymerase chain reaction. Finally, we explored the role of ASBEL in tumor development by silencing or overexpressing ASBEL gene in AsPC-1 or CFPAC-1 cells, respectively, and evaluated the antitumor activity in vivo using an ASBEL antagonist. Results: Our study revealed the expression of ASBEL in all pancreatic cell lines. The expression level of ASBEL in tumor tissues was found to be higher than that of paracarcinomatous tissues. ASBEL suppresses expression of BTG3, enhances proliferation and suppresses apoptosis, and promotes migration and invasion in pancreatic cancer cell. Antagonist regulates the expression of ASBEL in AsPC-1, and suppresses tumor growth in xenograft mouse model. Conclusions: Our results indicate that ASBEL may play a tumor-promoting factor in PDAC by targeting BTG3 and could be as an important biomarker for PDAC treatment. (Curr Ther Res Clin Exp. 2023; 84:XXX-XXX).

4.
J Med Virol ; 94(9): 4287-4293, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35614524

RESUMO

The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, sublineages BA.1 and BA.2, recently became the dominant variants of concern (VOCs) with significantly higher transmissibility than any other variant appeared and markedly greater resistance to neutralization antibodies and original ancestral WA1 spike-matched vaccine. Therefore, it is urgent to develop vaccines against VOCs like Omicron. Unlike the new booming messenger RNA (mRNA) vaccine, protein vaccines have been used for decades to protect people from various kinds of viral infections and have advantages with their inexpensive production protocols and their relative stability in comparison to the mRNA vaccine. Here, we show that sera from BA.1 spike protein vaccinated mice mainly elicited neutralizing antibodies against BA.1 itself. However, a booster with BA.1 spike protein or a bivalent vaccine composed of D614G and BA.1 spike protein-induced not only potent neutralizing antibody response against D614G and BA.1 pseudovirus, but also against BA.2, other four SARS-CoV-2 VOCs (Alpha, Beta, Gamma, and Delta) and SARS-CoV-2-related coronaviruses (pangolin CoV GD-1 and bat CoV RsSHC014). The two recombinant spike protein vaccines method described here lay a foundation for future vaccine development for broad protection against pan-sarbecovirus.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Combinadas , Vacinas Sintéticas/imunologia , Vacinas de mRNA/imunologia
5.
PLoS Genet ; 15(9): e1008368, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31518356

RESUMO

Telomere shortening is associated with aging and age-associated diseases. Additionally, telomere dysfunction resulting from telomerase gene mutation can lead to premature aging, such as apparent skin atrophy and hair loss. However, the molecular signaling linking telomere dysfunction to skin atrophy remains elusive. Here we show that dysfunctional telomere disrupts BMP/pSmad/P63 signaling, impairing epidermal stem cell specification and differentiation of skin and hair follicles. We find that telomere shortening mediated by Terc loss up-regulates Follistatin (Fst), inhibiting pSmad signaling and down-regulating P63 and epidermal keratins in an ESC differentiation model as well as in adult development of telomere-shortened mice. Mechanistically, short telomeres disrupt PRC2/H3K27me3-mediated repression of Fst. Our findings reveal that skin atrophy due to telomere dysfunction is caused by a previously unappreciated link with Fst and BMP signaling that could be explored in the development of therapies.


Assuntos
Células-Tronco/metabolismo , Encurtamento do Telômero/fisiologia , Animais , Atrofia/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Proliferação de Células/genética , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Regulação da Expressão Gênica/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Transdução de Sinais/genética , Proteínas Smad/metabolismo , Telômero/genética , Encurtamento do Telômero/genética , Transativadores/metabolismo
6.
BMC Plant Biol ; 21(1): 416, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507525

RESUMO

BACKGROUND: Leaf color variation is a common trait in plants and widely distributed in many plants. In this study, a leaf color mutation in Camellia japonica (cultivar named as Maguxianzi, M) was used as material, and the mechanism of leaf color variation was revealed by physiological, cytological, transcriptome and microbiome analyses. RESULTS: The yellowing C. japonica (M) exhibits lower pigment content than its parent (cultivar named as Huafurong, H), especially chlorophyll (Chl) and carotenoid, and leaves of M have weaker photosynthesis. Subsequently, the results of transmission electron microscopy(TEM) exhibited that M chloroplast was accompanied by broken thylakoid membrane, degraded thylakoid grana, and filled with many vesicles. Furthermore, comparative transcriptome sequencing identified 3,298 differentially expressed genes (DEGs). KEGG annotation analysis results showed that 69 significantly enriched DEGs were involved in Chl biosynthesis, carotenoid biosynthesis, photosynthesis, and plant-pathogen interaction. On this basis, we sequenced the microbial diversity of the H and M leaves. The sequencing results suggested that the abundance of Didymella in the M leaves was significantly higher than that in the H leaves, which meant that M leaves might be infected by Didymella. CONCLUSIONS: Therefore, we speculated that Didymella infected M leaves while reduced Chl and carotenoid content by damaging chloroplast structures, and altered the intensity of photosynthesis, thereby causing the leaf yellowing phenomenon of C. japonica (M). This research will provide new insights into the leaf color variation mechanism and lay a theoretical foundation for plant breeding and molecular markers.


Assuntos
Camellia/anatomia & histologia , Camellia/genética , Camellia/metabolismo , Cor , Microbiota , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Carotenoides/metabolismo , China , Clorofila/metabolismo , Produtos Agrícolas/anatomia & histologia , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Variação Genética , Genótipo , Fenótipo , Transcriptoma
7.
Nucleic Acids Res ; 46(7): 3468-3486, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29447390

RESUMO

Embryonic stem cells (ESCs) and meiosis are featured by relatively higher frequent homologous recombination associated with DNA double strand breaks (DSB) repair. Here, we show that Pold3 plays important roles in DSB repair, telomere maintenance and genomic stability of both ESCs and spermatocytes in mice. By attempting to generate Pold3 deficient mice using CRISPR/Cas9 or transcription activator-like effector nucleases, we show that complete loss of Pold3 (Pold3-/-) resulted in early embryonic lethality at E6.5. Rapid DNA damage response and massive apoptosis occurred in both outgrowths of Pold3-null (Pold3-/-) blastocysts and Pold3 inducible knockout (iKO) ESCs. While Pold3-/- ESCs were not achievable, Pold3 iKO led to increased DNA damage response, telomere loss and chromosome breaks accompanied by extended S phase. Meanwhile, loss of Pold3 resulted in replicative stress, micronucleation and aneuploidy. Also, DNA repair was impaired in Pold3+/- or Pold3 knockdown ESCs. Moreover, Pold3 mediates DNA replication and repair by regulating 53BP1, RIF1, ATR and ATM pathways. Furthermore, spermatocytes of Pold3 haploinsufficient (Pold3+/-) mice with increasing age displayed impaired DSB repair, telomere shortening and loss, and chromosome breaks, like Pold3 iKO ESCs. These data suggest that Pold3 maintains telomere integrity and genomic stability of both ESCs and meiosis by suppressing replicative stress.


Assuntos
DNA Polimerase III/genética , Replicação do DNA/genética , Células-Tronco Embrionárias/metabolismo , Instabilidade Genômica/genética , Telômero/genética , Animais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Sistemas CRISPR-Cas/genética , Quebras de DNA de Cadeia Dupla , Dano ao DNA/genética , Reparo do DNA/genética , Meiose/genética , Camundongos Knockout , Proteínas de Ligação a Telômeros/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética
8.
BMC Biol ; 15(1): 114, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29216888

RESUMO

BACKGROUND: Telomere length heterogeneity has been detected in various cell types, including stem cells and cancer cells. Cell heterogeneity in pluripotent stem cells, such as embryonic stem cells (ESCs), is of particular interest; however, the implication and mechanisms underlying the heterogeneity remain to be understood. Single-cell analysis technology has recently been developed and effectively employed to investigate cell heterogeneity. Yet, methods that can simultaneously measure telomere length and analyze the global transcriptome in the same cell have not been available until now. RESULTS: We have established a robust method that can simultaneously measure telomere length coupled with RNA-sequencing analysis (scT&R-seq) in the same human ESC (hESC). Using this method, we show that telomere length varies with pluripotency state. Compared to those with long telomere, hESCs with short telomeres exhibit the lowest expressions of TERF1/TRF1, and ZFP42/REX1, PRDM14 and NANOG markers for pluripotency, suggesting that these hESCs are prone to exit from the pluripotent state. Interestingly, hESCs ubiquitously express NOP10 and DKC1, stabilizing components of telomerase complexes. Moreover, new candidate genes, such as MELK, MSH6, and UBQLN1, are highly expressed in the cluster of cells with long telomeres and higher expression of known pluripotency markers. Notably, short telomere hESCs exhibit higher oxidative phosphorylation primed for lineage differentiation, whereas long telomere hESCs show elevated glycolysis, another key feature for pluripotency. CONCLUSIONS: Telomere length is a marker of the metabolic activity and pluripotency state of individual hESCs. Single cell analysis of telomeres and RNA-sequencing can be exploited to further understand the molecular mechanisms of telomere heterogeneity.


Assuntos
Células-Tronco Embrionárias Humanas/fisiologia , RNA/metabolismo , Análise de Sequência de RNA/métodos , Homeostase do Telômero/fisiologia , Telômero/fisiologia , Humanos
9.
Heliyon ; 10(14): e34492, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39148990

RESUMO

Given the significant decline in vaccine efficacy against Omicron, the development of novel vaccines with specific or broad-spectrum effectiveness is paramount. In this study, we formulated four monovalent vaccines based on recombinant spike trimer proteins, along with three bivalent vaccines, and five monovalent vaccines based on recombinant spike proteins. We evaluated the efficacy of different vaccination regimens in eliciting neutralizing antibodies in mice through pseudovirus neutralization assays. Following two doses of primary immunization with D614G, mice received subsequent immunizations with Omicron (BA.1, BA.2, BA.4/5) boosters individually, which led to the generation of broader and more potent cross-neutralizing activity compared to D614G boosters. Notably, the BA.4/5 booster exhibited superior efficacy. Following two doses of primary immunization with Omicron (BA.1, BA.2, BA.4/5), mice were subsequently immunized with one dose of D614G booster which resulted in broader neutralizing activity compared to one dose of Omicron (BA.1, BA.2, or BA.4/5). In unvaccinated mice, full-course immunization with different bivalent vaccines induced broad neutralizing activity against Omicron and pre-Omicron variants, with D614G&BA.4/5 demonstrating superior efficacy. However, compared to other variants, the neutralizing activity against XBB.1.5/1.9.1 is notably reduced. This observation emphasizes the necessity of timely updates to the vaccine antigen composition. Based on these findings and existing studies, we propose a vaccination strategy aimed at preserving the epitope repertoire to its maximum potential: (1) Individuals previously vaccinated or infected with pre-Omicron variants should inoculate a monovalent vaccine containing Omicron components; (2) Individuals who have only been vaccinated or infected with Omicron should be inoculated a monovalent vaccine containing pre-Omicron variants components; (3) Individuals without SARS-CoV-2 infection and vaccination should inoculate a bivalent vaccine comprising both pre-Omicron and Omicron components for primary immunization. Additionally, through cross-inoculation of SARS-CoV-2 D614G spike trimer protein and SARS-CoV-1 spike protein in mice, we preliminarily demonstrated the possibility of cross-reaction between different coronavirus vaccines to produce resistance to the pan-coronavirus.

10.
Artigo em Inglês | MEDLINE | ID: mdl-39388199

RESUMO

Single-cell RNA sequencing (scRNA-seq) has transformed our understanding of cellular diversity with unprecedented resolution. However, many current methods are limited in capturing full-length transcripts and discerning strand orientation. We present RAG-seq, an innovative strand-specific total RNA sequencing technique that combines not-so-random (NSR) primers with Tn5 transposase-mediated tagmentation. RAG-seq overcomes previous limitations by delivering comprehensive transcript coverage and maintaining strand orientation, which is essential for accurate quantification of overlapping genes and detection of antisense transcripts. Through optimized reverse transcription with oligo dT primers, rRNA depletion via Depletion of Abundant Sequences by Hybridization (DASH), and linear amplification, RAG-seq enhances sensitivity and reproducibility, especially for low-input samples and single cells. Application to mouse oocytes and early embryos highlights RAG-seq's superior performance in identifying stage-specific antisense transcripts, shedding light on their regulatory roles during early development. This advancement represents a significant leap in transcriptome analysis within complex biological contexts.

11.
Am J Transl Res ; 15(12): 6779-6785, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38186982

RESUMO

OBJECTIVE: To elucidate the effect of aspirin (ASP) on the biological behavior of gallbladder carcinoma (GBC) cells and its influence on vascular endothelial growth factor (VEGF) expression. METHODS: Cell Counting Kit-8 (CCK-8) assay was performed to determine the effects of ASP on GBC-SD cell proliferation. In addition, Transwell assay and flow cytometry were carried out to observe the role of ASP in GBC-SD cell migration, invasion and apoptosis, respectively. Tumor necrosis factor-α (TNF-α), nuclear factor kappa-B (NF-κB), and VEGF concentrations in GBC-SD cells were examined by enzyme-linked immunosorbent assays (ELISAs). RESULTS: ASP suppressed GBC-SD cell proliferation in a dose-dependent manner, and a concentration ≥ 2 mmol/L could significantly inhibit the migration and invasion of GBC-SD cells and induce apoptosis. In addition, the anticancer effect of ASP in GBC-SD cells may be linked to its inhibition of TNF-α, NF-κB, and VEGF levels. CONCLUSIONS: ASP may markedly inhibit GBC-SD cell growth by significantly reducing TNF-α, NF-κB and VEGF expression.

12.
Genes Genomics ; 45(11): 1433-1443, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37523127

RESUMO

BACKGROUND: Metastasis of liver cancer (LC) is the main cause of its high mortality. ETV4 is a critical regulatory factor in promoting LC progression, but the mechanism that ETV4 impacts LC proliferation, migration, and invasion is poorly understood. OBJECTIVE: Investigation of the molecular mechanism of LC metastasis is conducive to developing effective drugs that prevent LC metastasis. METHODS: Expression of ETV4 and its target gene B3GNT3 in LC tissue was analyzed by bioinformatics, and the result was further verified in LC cells by qRT-PCR. In vitro cellular assays evaluated the impact of ETV4 on the proliferation, migration, and invasion of LC cells. Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter gene assay were conducted to analyze the interaction between B3GNT3 and ETV4. SB525334 suppressor was used to treat and access the activation of ETV4 on the TGF-ß pathway. RESULTS: We discovered that ETV4 and B3GNT3 were evidently up-regulated in LC, and high expression of ETV4 was coupled to the increase of proliferation, migration, and invasion of LC cells and epithelial-mesenchymal transition ability. Besides, ETV4 could bind to the B3GNT3 promoter and activate its transcription. Knockdown of B3GNT3 could prominently suppress the effect of up-regulated ETV4 on LC cells. Meanwhile, ETV4 could activate the TGF-ß signaling pathway via B3GNT3, while SB525334 treatment notably repressed the functions of ETV4. CONCLUSION: ETV4 emerges as a driven oncogene in LC, and the ETV4/B3GNT3-TGF-ß pathway promotes proliferation, migration, invasion, and epithelial-mesenchymal transition progress of LC. Inhibition of the pathway may provide an underlying method for the prevention and treatment of LC metastasis.

13.
Open Med (Wars) ; 18(1): 20230661, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020523

RESUMO

Our pre-investigation has revealed that long non-coding RNA (LncRNA) AL137789.1 has the potential to predict the survival of patients with pancreatic carcinoma (PCa). Accordingly, the mechanism underlying the implication of AL137789.1 in PCa is covered in the current study. The non-tumor and paired tumor tissues were collected. Kaplan-Meier curve was employed to estimate the survival of PCa patients with high or low expression of AL137789.1. The proliferation, migration, invasion, and cell cycle of PCa cells were determined, and the cytotoxicity of CD8+ T cells was evaluated as well. Levels of AL137789.1, E-cadherin, N-cadherin, and Vimentin were quantified. According to the experimental results, AL137789.1 was highly expressed in PCa and related to a poor prognosis of patients. Overexpressed AL137789.1 enhanced the proliferation, migration, and invasion of PCa cells, increased the cell population at G2/M and S phases yet decreased that in G0/G1 phase, and diminished the cytotoxicity of CD8+ T cells. Also, overexpressed AL137789.1 elevated levels of N-cadherin and Vimentin, while lessening E-cadherin levels. However, the silencing of AL137789.1 produced contrary effects. Collectively, lncRNA AL137789.1 plays a tumor-promotive role in PCa by enhancing the progression and immune escape.

14.
Cell Signal ; 107: 110661, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36990335

RESUMO

Pancreatic cancer (PC) ranks third in incidence and seventh in mortality among cancers worldwide. CircZFR has been implicated in various human cancers. Yet, how they affect PC progression is understudied. Herein, we demonstrated that circZFR was upregulated in PC tissues and cells, a feature that was correlated with the poor performance of patients with PC. Functional analyses elucidated that circZFR facilitated cell proliferation and enhanced tumorigenicity of PC. Moreover, we found that circZFR facilitated cell metastasis by differentially regulating the levels of proteins related to epithelial-mesenchymal transition (EMT). Mechanistic investigations revealed that circZFR sponged miR-375, thereby upregulating the downstream target gene, GREMLIN2 (GREM2). Additionally, circZFR knockdown resulted in attenuation of the JNK pathway, an effect that was reversed by GREM2 overexpression. Collectively, our findings implicate circZFR as a positive regulator of PC progression through the miR-375/GREM2/JNK axis.


Assuntos
MicroRNAs , Neoplasias Pancreáticas , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Mensageiro/genética , Transição Epitelial-Mesenquimal/genética , Linhagem Celular Tumoral , Neoplasias Pancreáticas/patologia , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Neoplasias Pancreáticas
15.
Gene ; 851: 147029, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36356905

RESUMO

The DNA polymerase delta (Pol δ), a heterotetramer of four subunits (Pol δ4), plays a pivotal role in DNA replication, as well as in DNA damage repair. Pold4, as the smallest subunit of Pol δ, is degraded in response to DNA damage or when entering into S-phase. This leads to the conversion of Pol δ4 to the trimeric complex Pol δ3. However, the contribution of Pold4 has not been fully elucidated in mammals. Cdm1, the Pold4 ortholog in Schizosaccharomyces pombe, is dispensable for cell growth and DNA damage repair, and there are no Pold4 orthologs in Saccharomyces cerevisiae. We previously generated a knockout mouse model of Pold3 and revealed its essential role in genome stability. Unexpectedly, we here found that Pold4 knockout mice are viable and fertile. In addition, Pold4 knockout mice do not exhibit any pathologic changes in the lung and spleen, tissues with the most abundant expression of Pold4. Moreover, Pold4 knockout mouse tail tip fibroblasts (TTF) exhibited normal cell growth, cell cycle, DNA replication, DNA damage and DNA repair capacity. These results suggested that Pol δ3 but not Pol δ4 may be responsible for these processes in normal cells. Interestingly, 19-month-old wild-type (WT) mice had tumors in the liver, while Pold4 knockout mice did not, and Pold4 knockout mice showed increased longevity. In further, this provided evidence suggested that Pold4 could be a potential novel target for lung carcinoma because its depletion does not affect normal cells but does affect cancer cells.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Camundongos , Animais , Replicação do DNA/genética , Reparo do DNA/genética , DNA Polimerase III/genética , Dano ao DNA , Ciclo Celular , Camundongos Knockout , Saccharomyces cerevisiae , Mamíferos
16.
Front Public Health ; 10: 976686, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684881

RESUMO

Background: Optimizing adjuvant is one of the critical methods to improve the vaccine. 3M-052, a novel TLR7/8 agonist which was designed for slow dissemination at the injection site, has a potential as adjuvant, but its performance as a vaccine adjuvant for SARS-CoV-2 (B.1.617.2) spike protein has not been studied. The present study aimed to evaluate the effect of Alum-3M-052 as an adjuvant to improve mice serum antibody titers and pseudovirus neutralization efficiency. Method: Female Balb/c mice were immunized 3 times at day 0, 7 and 21 intramuscularly with SARS-CoV-2 (B.1.617.2) spike protein and adjuvant (Alum or Alum-3M-052). Mice serum was collected weekly since day 7. Antibody titers of mice serum anti-SARS-CoV-2 (B.1.617.2) IgG and IgM were detected by ELISA. Inhibition rates of mice serum blocking SARS-CoV-2 (B.1.617.2) spike protein binding to ACE2 were detected by SARS-CoV-2 (B.1.617.2) Inhibitor Screening Kit. Neutralization efficiencies of mice serum against both SARS-CoV-2 (BA.2.12.1) pseudovirus and SARS-CoV-2 (B.1.617.2) pseudovirus were detected by pseudovirus neutralizing assay. Result: Serum of mice immunized by SARS-CoV-2 (B.1.617.2) spike protein adjuvanted with Alum-3M-052 had highest antibody titers and higher neutralization efficiency against both SARS-CoV-2 (BA.2.12.1) pseudovirus and SARS-CoV-2 (B.1.617.2) pseudovirus. Besides, neutralization efficiency of anti-SARS-CoV-2 (B.1.617.2) spike protein antibody against SARS-CoV-2 (BA.2.12.1) pseudovirus was lower than that of SARS-CoV-2 (B.1.617.2) pseudovirus. Conclusion: Alum-3M-052 rapidly increased the titer of anti-SARS-CoV-2 (B.1.617.2) spike protein neutralizing antibodies and enhanced the neutralization ability against pseudoviruses and variants. This study provided evidence for the application of Alum-3M-052 as an adjuvant in COVID-19 vaccines production.


Assuntos
Formação de Anticorpos , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Feminino , Humanos , Camundongos , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
17.
Cells ; 11(3)2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35159266

RESUMO

Proper telomere length is essential for indefinite self-renewal of embryonic stem (ES) cells and cancer cells. Telomerase-deficient late generation mouse ES cells and human ALT cancer cells are able to propagate for numerous passages, suggesting telomerase-independent mechanisms responding for telomere maintenance. However, the underlying mechanisms ensuring the telomere length maintenance are unclear. Here, using late generation telomerase KO (G4 Terc-/-) ESCs as a model, we show that Zscan4, highly upregulated in G4 Terc-/- ESCs, is responsible for the prolonged culture of these cells with stably short telomeres. Mechanistically, G4 Terc-/- ESCs showed reduced levels of DNA methylation and H3K9me3 at Zscan4 promoter and subtelomeres, which relieved the expression of Zscan4. Similarly, human ZSCAN4 was also derepressed by reduced H3K9me3 at its promoter in ALT U2 OS cells, and depletion of ZSCAN4 significantly shortened telomeres. Our results define a similar conserved pathway contributing to the telomere maintenance in telomerase-deficient late generation mESCs and human ALT U2OS cancer cells.


Assuntos
Neoplasias , Telomerase , Animais , Metilação de DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos , Células-Tronco Embrionárias Murinas , Neoplasias/genética , Neoplasias/metabolismo , Telomerase/genética , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo , Homeostase do Telômero , Fatores de Transcrição/metabolismo
18.
World J Clin Cases ; 10(27): 9790-9797, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36186218

RESUMO

BACKGROUND: Synchronous primary cancers (SPCs) have become increasingly frequent over the past decade. However, the coexistence of duodenal papillary and gallbladder cancers is rare, and such cases have not been previously reported in the English literature. Here, we describe an SPC case with duodenal papilla and gallbladder cancers and its diagnosis and successful management. CASE SUMMARY: A 68-year-old Chinese man was admitted to our hospital with the chief complaint of dyspepsia for the past month. Contrast-enhanced computed tomography of the abdomen performed at the local hospital revealed dilatation of the bile and pancreatic ducts and a space-occupying lesion in the duodenal papilla. Endoscopy revealed a tumor protruding from the duodenal papilla. Pathological findings for the biopsied tissue revealed tubular villous growth with moderate heterogeneous hyperplasia. Surgical treatment was selected. Macroscopic examination of this surgical specimen revealed a 2-cm papillary tumor and another tumor protruding by 0.5 cm in the gallbladder neck duct. Intraoperative rapid pathology identified adenocarcinoma in the gallbladder neck duct and tubular villous adenoma with high-grade intraepithelial neoplasia and local canceration in the duodenal papilla. After an uneventful postoperative recovery, the patient was discharged without complications. CONCLUSION: It is essential for clinicians and pathologists to maintain a high degree of suspicion while evaluating such synchronous cancers.

19.
MedComm (2020) ; 3(2): e143, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35592756

RESUMO

The SARS-CoV-2 Omicron BA.1 variant of concern contains more than 30 mutations in the spike protein, with half of these mutations localized in the receptor-binding domain (RBD). Emerging evidence suggests that these large number of mutations impact the neutralizing efficacy of vaccines and monoclonal antibodies. We investigated the relative contributions of spike protein and RBD mutations in Omicron BA.1 variants on infectivity, cell-cell fusion, and their sensitivity to neutralization by monoclonal antibodies or vaccinated sera from individuals who received homologous (CoronaVac, SinoPharm) or heterologous (CoronaVac-BNT162b2, BioNTech) and nonhuman primates that received a recombinant RBD protein vaccine. Our data overall reveal that the mutations in the spike protein reduced infectivity and cell-cell fusion compared to the D614G variant. The impaired infectivity and cell-cell fusion were dependent on non-RBD mutations. We also find reduced sensitivity to neutralization by monoclonal antibodies and vaccinated sera. However, our results also show that nonhuman primates receiving a recombinant RBD protein vaccine show substantial neutralization activity. Our study sheds light on the molecular differences in neutralizing antibody escape by the Omicron BA.1 variant, and highlights the promise of recombinant RBD vaccines in neutralizing the threat posed by the Omicron BA.1 variant.

20.
Am J Transl Res ; 13(4): 3634-3641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017545

RESUMO

OBJECTIVE: To compare the effects and prognosis of concurrent and staged resections for the treatment of resectable colorectal cancer liver metastasis (CRLM). METHODS: A prospective study was conducted on 118 patients with CRLM. The 59 cases in the observation group received concurrent resections, while the 59 cases in the control group received staged resections. The operation time, intraoperative blood loss, length of hospital stay, hospital cost, postoperative complications, 5-year survival rate and 3-year progression-free survival rate were recorded for all patients. Factors that affect the prognosis of CRLM patients were analyzed. RESULTS: The length of hospital stay, operation time, intraoperative blood loss, hospital cost were significantly lower in the observation group than in the control group (P<0.001). The two groups were equivalent with respect to postoperative complications, 5-year survival rate and 3-year progression-free survival rate (P>0.05). Independent risk factors affecting the prognosis of CRLM included the number of liver metastasis, whether resection is feasible after recurrence, and RAS genotype (P<0.05). CONCLUSION: Compared to staged resection for CRLM, concurrent resection has shorter operation time, less blood loss, and shorter length of hospital stay, while postoperative complications, long-term efficacy and survival benefits are comparable. Furthermore, the study has found that the number of liver metastasis, whether or not resection is feasible after recurrence, and RAS genotype are risk factors affecting the prognosis of CRLM.

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