RESUMO
A fraction of mature T cells can be activated by peripheral self-antigens, potentially eliciting host autoimmunity. We investigated homeostatic control of self-activated T cells within unperturbed tissue environments by combining high-resolution multiplexed and volumetric imaging with computational modeling. In lymph nodes, self-activated T cells produced interleukin (IL)-2, which enhanced local regulatory T cell (Treg) proliferation and inhibitory functionality. The resulting micro-domains reciprocally constrained inputs required for damaging effector responses, including CD28 co-stimulation and IL-2 signaling, constituting a negative feedback circuit. Due to these local constraints, self-activated T cells underwent transient clonal expansion, followed by rapid death ("pruning"). Computational simulations and experimental manipulations revealed the feedback machinery's quantitative limits: modest reductions in Treg micro-domain density or functionality produced non-linear breakdowns in control, enabling self-activated T cells to subvert pruning. This fine-tuned, paracrine feedback process not only enforces immune homeostasis but also establishes a sharp boundary between autoimmune and host-protective T cell responses.
Assuntos
Retroalimentação Fisiológica , Homeostase/imunologia , Ativação Linfocitária/imunologia , Linfócitos T Reguladores/imunologia , Animais , Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células , Interleucina-2/metabolismo , Microdomínios da Membrana/metabolismo , Camundongos Endogâmicos C57BL , Modelos Imunológicos , Comunicação Parácrina , Transdução de SinaisRESUMO
BACKGROUND: The cytokine TSLP promotes type 2 immune responses and can induce adipose loss by stimulating lipid loss from the skin through sebum secretion by sebaceous glands, which enhances the skin barrier. However, the mechanism by which TSLP upregulates sebaceous gland function is unknown. OBJECTIVES: This study investigated the mechanism by which TSLP stimulates sebum secretion and adipose loss. METHODS: RNA-sequencing analysis was performed on sebaceous glands isolated by laser capture microdissection and single-cell RNA-sequencing analysis was performed on sorted skin T cells. Sebocyte function was analyzed by histological analysis and sebum secretion in vivo and by measuring lipogenesis and proliferation in vitro. RESULTS: This study found that TSLP sequentially stimulated the expression of lipogenesis genes followed by cell death genes in sebaceous glands to induce holocrine secretion of sebum. TSLP did not affect sebaceous gland activity directly. Rather, single-cell RNA-sequencing revealed that TSLP recruited distinct T-cell clusters that produce IL-4 and IL-13, which were necessary for TSLP-induced adipose loss and sebum secretion. Moreover, IL-13 was sufficient to cause sebum secretion and adipose loss in vivo and to induce lipogenesis and proliferation of a human sebocyte cell line in vitro. CONCLUSIONS: This study proposes that TSLP stimulates T cells to deliver IL-4 and IL-13 to sebaceous glands, which enhances sebaceous gland function, turnover, and subsequent adipose loss.
Assuntos
Citocinas , Interleucina-13 , Interleucina-4 , Glândulas Sebáceas , Sebo , Linfócitos T , Linfopoietina do Estroma do Timo , Citocinas/metabolismo , Sebo/metabolismo , Sebo/imunologia , Interleucina-13/metabolismo , Interleucina-13/imunologia , Interleucina-4/metabolismo , Interleucina-4/imunologia , Animais , Glândulas Sebáceas/imunologia , Glândulas Sebáceas/metabolismo , Linfócitos T/imunologia , Humanos , Camundongos , Tecido Adiposo/imunologia , Tecido Adiposo/metabolismo , Lipogênese/imunologia , Camundongos Endogâmicos C57BLRESUMO
Cellular infections by DNA viruses trigger innate immune responses mediated by DNA sensors. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING) signaling pathway has been identified as a DNA-sensing pathway that activates interferons in response to viral infection and, thus, mediates host defense against viruses. Previous studies have identified oncogenes E7 and E1A of the DNA tumor viruses, human papillomavirus 18 (HPV18) and adenovirus, respectively, as inhibitors of the cGAS-STING pathway. However, the function of STING in infected cells and the mechanism by which HPV18 E7 antagonizes STING-induced Interferon beta production remain unknown. We report that HPV18 E7 selectively antagonizes STING-triggered nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation but not IRF3 activation. HPV18 E7 binds to STING in a region critical for NF-κB activation and blocks the nuclear accumulation of p65. Moreover, E7 inhibition of STING-triggered NF-κB activation is related to HPV pathogenicity but not E7-Rb binding. HPV18 E7, severe acute respiratory syndrome coronavirus-2 open reading frame 3a, human immunodeficiency virus-2 viral protein X, and Kaposi's sarcoma-associated herpesvirus KSHV viral interferon regulatory factor 1 selectively inhibited STING-triggered NF-κB or IRF3 activation, suggesting a convergent evolution among these viruses toward antagonizing host innate immunity. Collectively, selective suppression of the cGAS-STING pathway by viral proteins is likely to be a key pathogenic determinant, making it a promising target for treating oncogenic virus-induced tumor diseases.
Assuntos
COVID-19 , NF-kappa B , Humanos , NF-kappa B/metabolismo , Interferon beta/genética , Papillomavirus Humano 18/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Imunidade Inata , DNA , Vírus de DNA/genética , Vírus de DNA/metabolismo , Proteínas OncogênicasRESUMO
A hallmark of the mammalian immune system is its ability to respond efficiently to foreign antigens without eliciting an inappropriate response to self-antigens. Furthermore, a robust immune response requires the coordination of a diverse range of cells present at low frequencies within the host. This problem is solved, in part, by concentrating antigens, antigen-presenting cells and antigen-responsive cells in lymph nodes (LNs). Beyond housing these cell types in one location, LNs are highly organized structures consisting of pre-positioned cells within well-defined microanatomical niches. In this Cell Science at a Glance article and accompanying poster, we outline the key cellular populations and components of the LN microenvironment that are present at steady state and chronicle the dynamic changes in these elements following an immune response. This review highlights the LN as a staging ground for both innate and adaptive immune responses, while providing an elegant example of how structure informs function.
Assuntos
Antígenos , Linfonodos , Animais , ImunidadeRESUMO
Ribonucleotide reductase (RR) is the rate-limiting enzyme in DNA synthesis, catalyzing the reduction of ribonucleotides to deoxyribonucleotides. During each enzymatic turnover, reduction of the active site disulfide in the catalytic large subunit is performed by a pair of shuttle cysteine residues in its C-terminal tail. Thioredoxin (Trx) and glutaredoxin (Grx) are ubiquitous redox proteins, catalyzing thiol-disulfide exchange reactions. Here, immunohistochemical examination of clinical colorectal cancer (CRC) specimens revealed that human thioredoxin1 (hTrx1), but not human glutaredoxin1 (hGrx1), was up-regulated along with human RR large subunit (RRM1) in cancer tissues, and the expression levels of both proteins were correlated with cancer malignancy stage. Ectopically expressed hTrx1 significantly increased RR activity, DNA synthesis, and cell proliferation and migration. Importantly, inhibition of both hTrx1 and RRM1 produced a synergistic anticancer effect in CRC cells and xenograft mice. Furthermore, hTrx1 rather than hGrx1 was the efficient reductase for RRM1 regeneration. We also observed a direct protein-protein interaction between RRM1 and hTrx1 in CRC cells. Interestingly, besides the known two conserved cysteines, a third cysteine (Cys779) in the RRM1 C terminus was essential for RRM1 regeneration and binding to hTrx1, whereas both Cys32 and Cys35 in hTrx1 played a counterpart role. Our findings suggest that the up-regulated RRM1 and hTrx1 in CRC directly interact with each other and promote RR activity, resulting in enhanced DNA synthesis and cancer malignancy. We propose that the RRM1-hTrx1 interaction might be a novel potential therapeutic target for cancer treatment.
Assuntos
Neoplasias Colorretais/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Tiorredoxinas/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Regulação para Cima , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Glutarredoxinas/biossíntese , Glutarredoxinas/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ribonucleosídeo Difosfato Redutase , Tiorredoxinas/genética , Proteínas Supressoras de Tumor/genéticaRESUMO
AIMS/HYPOTHESIS: Ginsenosides regulate glucose homeostasis. This study investigated the effect of ginsenoside Rg5 (Rg5) on the hepatic glucagon response, focusing on the regulation of metabolism. METHODS: Mice fed a high-fat diet (HFD) showed increased hepatic glucose production (HGP). We observed the effects of Rg5 on hepatic fatty acid oxidation and glucagon response. The regulation of phosphodiesterase (PDE) 4B by succinate was also investigated in hepatocytes. RESULTS: Rg5 inhibited endogenous glucose production in HFD-fed mice. Rg5 reduced cyclic AMP (cAMP) accumulation and inhibited transcriptional regulation of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) by dephosphorylation of the cAMP response element-binding transcription factor in the liver, demonstrating the inhibitory effect on hepatic glucagon response. HFD feeding increased succinate accumulation in the liver due to the reversal of succinate dehydrogenase activation and triggered hypoxia-inducible factor-1α (HIF-1α) induction. Succinate prevented cAMP degradation by inactivating PDE4B, thereby increasing cAMP accumulation in response to glucagon. Knockdown of HIF-1α with small interfering RNA diminished the effect of succinate, indicating that HIF-1α was essential for succinate to inactivate PDE4B. Rg5 inhibited succinate accumulation in hepatocytes by combating fatty acid oxidation, and thus reduced cAMP accumulation by blocking succinate/HIF-1α induction. Rg5 reduced HGP as a consequence of the inhibition of the glucagon response. CONCLUSIONS/INTERPRETATION: Succinate acted as a metabolic signal to enhance the hepatic glucagon response. Rg5 reduced hepatic succinate accumulation by combating fatty acid oxidation and attenuated the hepatic glucagon response by suppressing succinate/HIF-1α induction, suggesting that succinate-associated HIF-1α induction in hepatocytes might be a therapeutic target in the treatment of diabetes.
Assuntos
Ginsenosídeos/farmacologia , Glucagon/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fígado/metabolismo , Ácido Succínico/metabolismo , Animais , AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), an alkylating agent and an environmental carcinogen, causes DNA lesions and even carcinomas. DNA damage responses induced by MNNG activate various DNA repair genes and related signaling pathways. The present study aimed to investigate the regulatory mechanisms of human RR small subunit M2 (hRRM2) in response to MNNG. RESULTS: In this study, we demonstrated that the RRM2 gene was transactivated by MNNG exposure more strongly than the other small subunit, p53R2. The upregulated RRM2 translocated to the nucleus for DNA repair. Further study showed that E2F3 transactivated RRM2 expression by directly binding to its promoter after MNNG exposure. The transactivation was enhanced by the upregulation of NFY, which bound to the RRM2 promoter adjacent to the E2F3 binding site and interacted with E2F3. In response to MNNG treatment, E2F3 accumulated mainly through its phosphorylation at S124 and was dependent on ATR-CHK1 signaling. In comparison, p53R2 played a relatively weaker role in the MNNG-induced DNA damage response, and its transcription was regulated by the ATR-CHK2-E2F1/p53 pathway. CONCLUSIONS: We suggest that MNNG-stimulated ATR/CHK1 signaling stabilizes E2F3 by S124 phosphorylation, and then E2F3 together with NFY co-transactivate RRM2 expression for DNA repair. GENERAL SIGNIFICANCE: We propose a new mechanism for RRM2 regulation to maintain genome stability in response to environmental chemical carcinogens.
Assuntos
Dano ao DNA/efeitos dos fármacos , Fator de Transcrição E2F3/metabolismo , Proteínas Quinases/metabolismo , Ribonucleosídeo Difosfato Redutase/biossíntese , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Fator de Ligação a CCAAT/biossíntese , Carcinógenos/toxicidade , Quinase 1 do Ponto de Checagem , Reparo do DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Fator de Transcrição E2F3/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genoma Humano/efeitos dos fármacos , Instabilidade Genômica , Humanos , Metilnitronitrosoguanidina/toxicidade , Fosforilação , Proteínas Quinases/genética , Ribonucleosídeo Difosfato Redutase/genética , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/genéticaRESUMO
BACKGROUND The role that nc886, a non-coding microRNA, plays in human endometrial cancer is unknown. The present study aimed to describe the functional role of nc886 in human endometrial cancer-1A (HEC-1A) cell line, which may provide another target for human endometrial cancer treatment. MATERIAL AND METHODS The expression levels of nv886 in normal human endometrial tissue and the early phase and late phase of human endometrial cancer tissues were determined and compared by fluorescence in situ hybridization (FISH). Small interference RNA (siRNA) was used to inhibit nc886, and cell proliferation was evaluated with the MTT test. mRNA levels of PKR, NF-κB, vascular endothelial growth factor (VEGF), and caspase-3 were determined against glyceraldehyde 3-phosphate dehydrogenase (GAPDH between the HEC-1A control group and the silenced group (nc886 silenced with siRNA) by real-time reverse transcription polymerase chain reaction (RT-PCR). The protein levels of PKR (total and phosphorylated form), NF-κB, VEGF, and caspase-3 were determined against GAPDH by Western blotting, and cell apoptosis was determined by flow cytometry. RESULTS Our results indicated that a higher level of nc886 was expressed in the late phase of human endometrial cancer tissue, less than in the early phase but still higher than in normal human endometrial tissue. After nc886 was silenced, protein levels of p-PKR (phosphorylated PKR) and caspase-3 were increased, whereas NF-κB and VEGF were decreased. CONCLUSIONS The rate of apoptosis in the silenced group was increased and the rate of cell proliferation was slower in comparison to the control.
Assuntos
Neoplasias do Endométrio/genética , Neoplasias do Endométrio/terapia , Tumores do Estroma Endometrial/genética , Tumores do Estroma Endometrial/terapia , MicroRNAs/genética , Apoptose/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias do Endométrio/metabolismo , Tumores do Estroma Endometrial/metabolismo , Feminino , Inativação Gênica , Células HeLa , Humanos , Hibridização in Situ Fluorescente , MicroRNAs/metabolismo , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , TransfecçãoRESUMO
Ribonucleotide reductase (RR) catalyzes the reduction of ribonucleotides to deoxyribonucleotides for DNA synthesis. Human RR small subunit M2 exists in a homodimer form. However, the importance of the dimer form to the enzyme and the related mechanism remain unclear. In this study, we tried to identify the interfacial residues that may mediate the assembly of M2 homodimer by computational alanine scanning based on the x-ray crystal structure. Co-immunoprecipitation, size exclusion chromatography, and RR activity assays showed that the K95E mutation in M2 resulted in dimer disassembly and enzyme activity inhibition. In comparison, the charge-exchanging double mutation of K95E and E98K recovered the dimerization and activity. Structural comparisons suggested that a conserved cluster of charged residues, including Lys-95, Glu-98, Glu-105, and Glu-174, at the interface may function as an ionic lock for M2 homodimer. Although the measurements of the radical and iron contents showed that the monomer (the K95E mutant) was capable of generating the diiron and tyrosyl radical cofactor, co-immunoprecipitation and competitive enzyme inhibition assays indicated that the disassembly of M2 dimer reduced its interaction with the large subunit M1. In addition, the immunofluorescent and fusion protein-fluorescent imaging analyses showed that the dissociation of M2 dimer altered its subcellular localization. Finally, the transfection of the wild-type M2 but not the K95E mutant rescued the G1/S phase cell cycle arrest and cell growth inhibition caused by the siRNA knockdown of M2. Thus, the conserved Lys-95 charged residue cluster is critical for human RR M2 homodimerization, which is indispensable to constitute an active holoenzyme and function in cells.
Assuntos
Ácido Glutâmico/metabolismo , Lisina/metabolismo , Multimerização Proteica , Ribonucleosídeo Difosfato Redutase/metabolismo , Substituição de Aminoácidos , Biocatálise , Proliferação de Células , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Ácido Glutâmico/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Células HeLa , Humanos , Immunoblotting , Lisina/genética , Microscopia Confocal , Modelos Moleculares , Mutação , Interferência de RNA , Ribonucleosídeo Difosfato Redutase/química , Ribonucleosídeo Difosfato Redutase/genéticaRESUMO
The significance of steroidogenic factor-1 (SF-1) in human ovarian tumor has not been fully investigated. The purposes of this study are to provide a meta-analysis for SF-1 and to determine whether SF-1 is associated with ovarian tumor progression and clinicopathological characteristics. A detailed literature search was made for related research publications written in English. Methodological quality of the studies was also evaluated. The data were extracted and assessed by two reviewers independently. Analysis of pooled data was performed, and odds ratio (OR) and corresponding confidence intervals (CIs) were calculated and summarized respectively. Final analysis from seven eligible studies was performed. Aberrant SF-1 expression was significantly lower in ovarian cancer compared to that of normal ovarian tissue (OR = 0.02, 95% CI = 0.00-0.16, p = 0.0002). However, SF-1 protein expression was not significantly different between benign and malignant ovarian tumors (p = 0.35). Interestingly, aberrant SF-1 expression was significantly higher in ovarian sex cord stromal tumors than that of ovarian cancer (OR = 0.00, 95% CI = 0.00-0.01, p < 0.00001). The results of this meta-analysis suggest that SF-1 may play an important role in ovarian cancer initiation and progression. Moreover, SF-1 expression may serve as a marker in the differential diagnosis between ovarian sex cord stromal tumors and ovarian cancer.
Assuntos
Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Tumores do Estroma Gonadal e dos Cordões Sexuais/metabolismo , Tumores do Estroma Gonadal e dos Cordões Sexuais/patologia , Fator Esteroidogênico 1/biossíntese , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Ovarianas/genética , Tumores do Estroma Gonadal e dos Cordões Sexuais/genética , Fator Esteroidogênico 1/genéticaRESUMO
Ribonucleotide reductase large subunit M1 (RRM1) forms a holoenzyme with small subunits to provide deoxyribonucleotides for DNA synthesis and cell proliferation. Here, we reported a non-RR role of the catalytic subunit protein RRM1 and related pathway in inhibiting colorectal cancer (CRC) metastasis. Ectopic overexpression of the wild-type RRM1, and importantly, its Y738F mutant that lacks RR enzymatic activity, prevented the migration and invasion of CRC cells by promoting phosphatase and tensin homolog on chromosome 10 (PTEN) transactivation. Furthermore, overexpression of the wild-type and RR-inactive mutant RRM1 similarly reduced the phosphorylation of Akt and increased the E-cadherin expression in CRC cells, which were blocked by PTEN knockdown attenuation. Examination of clinical CRC specimens demonstrated that both RRM1 protein expression and RR activity were elevated in most cancer tissues compared to the paired normal tissues. However, while RR activity did not change significantly in different cancer stages, the RRM1 protein level was significantly increased at stages T1-3 but decreased at stage T4, in parallel with the PTEN expression level and negatively correlated with invasion and liver metastasis. Thus, we propose that RRM1 protein can inhibit CRC invasion and metastasis at the advanced stage by regulating PTEN transactivation and its downstream pathways in addition to forming an RR holoenzyme for supporting cancer proliferation. Understanding of the seemingly contrary dual roles of RRM1 protein may further help to explain the complex mechanisms by which this key enzyme and its components are involved in cancer development.
Assuntos
Neoplasias Colorretais/genética , Invasividade Neoplásica/genética , PTEN Fosfo-Hidrolase/genética , Proteínas Supressoras de Tumor/biossíntese , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metástase Neoplásica , Estadiamento de Neoplasias , PTEN Fosfo-Hidrolase/biossíntese , Ribonucleosídeo Difosfato Redutase , Transdução de Sinais/genética , Proteínas Supressoras de Tumor/genéticaRESUMO
This study aimed at investigating the possible mechanisms of hepatic protective activity of Cichorium intybus L. (chicory) in acute liver injury. Pathological observation, reactive oxygen species (ROS) detection and measurements of biochemical indexes on mouse models proved hepatic protective effect of Cichorium intybus L. Identification of active compounds in Cichorium intybus L. was executed through several methods including ultra performance liquid chromatography/time of flight mass spectrometry (UPLC-TOF-MS). Similarity ensemble approach (SEA) docking, molecular modeling, molecular docking, and molecular dynamics (MD) simulation were applied in this study to explore possible mechanisms of the hepato-protective potential of Cichorium intybus L. We then analyzed the chemical composition of Cichorium intybus L., and found their key targets. Furthermore, in vitro cytological examination and western blot were used for validating the efficacy of the selected compounds. In silico analysis and western blot together demonstrated that selected compound 10 in Cichorium intybus L. targeted Akt-1 in hepatocytes. Besides, compound 13 targeted both caspase-1 and Akt-1. These small compounds may ameliorate liver injury by acting on their targets, which are related to apoptosis or autophagy. The conclusions above may shed light on the complex molecular mechanisms of Cichorium intybus L. acting on hepatocytes and ameliorating liver injury.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Cichorium intybus/química , Fígado/efeitos dos fármacos , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Animais , Apoptose , Autofagia , Sítios de Ligação , Caspase 1/química , Caspase 1/genética , Caspase 1/metabolismo , Fígado/metabolismo , Camundongos , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologiaRESUMO
OBJECTIVES: Focused ultrasound waves penetrate superficial tissues and are aimed toward the target tissues at specific depths to exert their biological effects. Focused ultrasound has been applied for a number of clinical indications, including vulval dystrophies and low-grade vulval disease. This study aimed to assess the efficacy and safety of focused ultrasound treatment of high-grade vulval intraepithelial neoplasia (VIN). METHODS: Eighteen women with high-grade VIN were recruited and treated with focused ultrasound. During each posttreatment follow-up, the safety of, side effects of, and clinical responses to focused ultrasound were evaluated by a standardized protocol, including symptoms, clinical appearance, and histologic findings. RESULTS: All patients completed the designed follow-ups. In most cases, superficial mild to moderate swelling and blisters were seen in the focused ultrasound-treated skin but not in adjacent normal skin. Of the 18 patients, 16 showed complete histologic regression and resolution of symptoms 6 months after treatment. Of the other 2 patients, 1 showed complete regression after a second focused ultrasound treatment. The other patient did not respond to the focused ultrasound treatment and underwent a partial vulvectomy 6 months after treatment. None of the patients developed invasive carcinoma of the vulva during the follow-up period. One patient had local pruritus that was not alleviated by anti-inflammatory medication and local care. CONCLUSIONS: The complete responses observed in women with high-grade VIN treated by focused ultrasound, together with the preservation of adjacent normal tissue, suggest that focused ultrasound may be considered for treatment of high-grade VIN.
Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/terapia , Dermatopatias/patologia , Dermatopatias/terapia , Doenças da Vulva/patologia , Doenças da Vulva/terapia , Adulto , Idoso , Carcinoma in Situ , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
DNA polymerase η (Polη) implements translesion DNA synthesis but has low fidelity in replication. We have previously shown that Polη plays an important role in the genesis of nontargeted mutations at undamaged DNA sites in cells exposed to the carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Here, we report that MNNG-induced Polη expression in an interferon regulatory factor 1 (IRF1)-dependent manner in human cells. Mutagenesis analysis showed that four critical residues (Arg-82, Cys-83, Asn-86, and Ser-87) located in the IRF family conserved DNA binding domain-helix α3 were involved in DNA binding and POLH transactivation by IRF1. Furthermore, Polη up-regulation induced by IRF1 was responsible for the increase of mutation frequency in a SupF shuttle plasmid replicated in the MNNG-exposed cells. Interestingly, IRF1 was acetylated by the histone acetyltransferase CBP in these cells. Lys â Arg substitution revealed that Lys-78 of helix α3 was the major acetylation site, and the IRF1-K78R mutation partially inhibited DNA binding and its transcriptional activity. Thus, we propose that IRF1 activation is responsible for MNNG-induced Polη up-regulation, which contributes to mutagenesis and ultimately carcinogenesis in cells.
Assuntos
Carcinógenos/toxicidade , DNA Polimerase Dirigida por DNA/genética , Células Epiteliais/enzimologia , Fator Regulador 1 de Interferon/metabolismo , Metilnitronitrosoguanidina/toxicidade , Acetilação/efeitos dos fármacos , Âmnio/citologia , Células Cultivadas , DNA Polimerase Dirigida por DNA/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Substâncias Perigosas/toxicidade , Humanos , Fator Regulador 1 de Interferon/química , Fator Regulador 1 de Interferon/genética , Mutagênese/fisiologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/fisiologia , Estrutura Terciária de Proteína , Regulação para Cima/fisiologiaRESUMO
Breast mass is one of the main clinical symptoms of breast cancer. Recently, many CNN-based methods for breast mass segmentation have been proposed. However, these methods have difficulties in capturing long-range dependencies, causing poor segmentation of large-scale breast masses. In this paper, we propose an axial Transformer and feature enhancement-based CNN (ATFE-Net) for ultrasound breast mass segmentation. Specially, an axial Transformer (Axial-Trans) module and a Transformer-based feature enhancement (Trans-FE) module are proposed to capture long-range dependencies. Axial-Trans module only calculates self-attention in width and height directions of input feature maps, which reduces the complexity of self-attention significantly from O(n2) to O(n). In addition, Trans-FE module can enhance feature representation by capturing dependencies between different feature layers, since deeper feature layers have richer semantic information and shallower feature layers have more detailed information. The experimental results show that our ATFE-Net achieved better performance than several state-of-the-art methods on two publicly available breast ultrasound datasets, with Dice coefficient of 82.46% for BUSI and 86.78% for UDIAT, respectively.
Assuntos
Processamento de Imagem Assistida por Computador , Semântica , UltrassonografiaRESUMO
Innate immunity represents one of the main host responses to viral infection.1-3 STING (Stimulator of interferon genes), a crucial immune adapter functioning in host cells, mediates cGAS (Cyclic GMP-AMP Synthase) sensing of exogenous and endogenous DNA fragments and generates innate immune responses.4 Whether STING activation was involved in infection and replication of enterovirus remains largely unknown. In the present study, we discovered that human enterovirus A71 (EV-A71) infection triggered STING activation in a cGAS dependent manner. EV-A71 infection caused mitochondrial damage and the discharge of mitochondrial DNA into the cytosol of infected cells. However, during EV-A71 infection, cGAS-STING activation was attenuated. EV-A71 proteins were screened and the viral protease 2Apro had the greatest capacity to inhibit cGAS-STING activation. We identified TRAF3 as an important factor during STING activation and as a target of 2Apro. Supplement of TRAF3 rescued cGAS-STING activation suppression by 2Apro. TRAF3 supported STING activation mediated TBK1 phosphorylation. Moreover, we found that 2Apro protease activity was essential for inhibiting STING activation. Furthermore, EV-D68 and CV-A16 infection also triggered STING activation. The viral protease 2Apro from EV-D68 and CV-A16 also had the ability to inhibit STING activation. As STING activation prior to EV-A71 infection generated cellular resistance to EV-A71 replication, blocking EV-A71-mediated STING suppression represents a new anti-viral target.
Assuntos
Enterovirus Humano A , Proteínas de Membrana , Fator 3 Associado a Receptor de TNF , Humanos , Antígenos Virais , Enterovirus Humano A/fisiologia , Nucleotidiltransferases/genética , Fator 3 Associado a Receptor de TNF/genética , Proteases Virais , Imunidade InataRESUMO
Breast cancer is a common life-threatening disease among women. Computer-aided methods can provide second opinion or decision support for early diagnosis in mammography images. However, the whole images classification is highly challenging due to small sizes of lesion and slow contrast between lesions and fibro-glandular tissue. In this paper, inspired by conventional machine learning methods, we present a Multi Frequency Attention Network (MFA-Net) to highlight the salient features. The network decomposes the features into low spatial frequency components and high spatial frequency components, and then recalibrates discriminating features based on two-dimensional Discrete Cosine Transform in two different frequency parts separately. Low spatial frequency features help determine if there is a tumor while high spatial frequency features help focus more on the margin of the tumor. Our studies empirically show that compared to traditional convolutional neural network (CNN), the proposed method mitigates the influence of the margin of pectoral muscle and breast in mammography, which brings significant improvement. For malignant and benign classification, by using transfer learning, the proposed MFA-Net achieves the AUC index 91.71% on the INbreast dataset.
Assuntos
Neoplasias da Mama , Mamografia , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Humanos , Aprendizado de Máquina , Mamografia/métodos , Margens de Excisão , Redes Neurais de ComputaçãoRESUMO
OBJECTIVE: LncRNA SOX2-OT is involved in a variety of cancers. This study explored the effect of lncRNA SOX2-OT on hepatocellular carcinoma (HCC) cells. METHODS: SOX2-OT expressions were detected in HCC tissues and normal tissues, normal cells, and HCC cells. The relationship between SOX2-OT and prognosis was analyzed by TCGA. After SOX2-OT expression was inhibited using siRNA, HCC cell malignant behaviors were evaluated. The subcellular localization of SOX2-OT in HCC cells was predicted and analyzed. The binding relationships among SOX2-OT, miR-143-3p, and MSI2 were analyzed by bioinformatics website, dual-luciferase assay, and RNA pull-down assay. The effect of miR-143-3p and MSI2 on the regulation of SOX2-OT on biological behaviors of HCC cells was confirmed by functional rescue experiments. The effect of SOX2-OT on the tumorigenicity of HCC was evaluated by subcutaneous tumorigenesis in nude mice. RESULTS: SOX2-OT was highly expressed in HCC cells and tissues. The prognosis was poor in HCC patients with high SOX2-OT expression. Downregulating SOX2-OT inhibited HCC cell malignant behaviors. SOX2-OT bound to miR-143-3p to promote MSI2 expression. Downregulating miR-143-3p or upregulating MSI2 averted the role of si-SOX2-OT in HCC cells. Nude mouse subcutaneous tumorigenesis showed that SOX2-OT downregulation decreased the tumorigenicity of HCC, and affected the levels of miR-143-3p and MSI2 mRNA in tumor tissues. CONCLUSION: SOX2-OT inhibited the targeted inhibition of miR-143-3p on MSI2 through competitively binding to miR-143-3p, thus promoting MSI2 expression and proliferation, invasion, and migration of HCC cells.
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Ovarian carcinoma is one of the major causes of gynecological cancer. This study aimed to evaluate the association of CYP1 family polymorphism with the risk of ovarian carcinoma and chemotherapy resistance. Positive selection was detected among human CYP1A1, CYP1A2, and CYP1B1, and other species. Several positive sites were detected by site models and brach-site models. Meta-analysis was conducted for the sites rs1056836 (MAF 0.39) and rs1056827 (MAF 0.36) of CYP1B1 to clarify the association between gene polymorphisms and ovarian carcinoma risk. Subgroup analysis showed the association of rs1056836 polymorphism with ovarian cancer risk among Caucasians and Asians, while all the six genetic models showed no association among African-Americans. All the six genetic models showed no association of rs1056827 polymorphism with ovarian cancer risk. The polymorphisms of rs1056836 associated with ovarian cancer risk were detected in chemotherapy-sensitive and drug-resistant ovarian cancer patients. DNA was extracted from 62 chemotherapy resistance Ovarian carcinoma tissue samples and 137 chemotherapy-sensitive ovarian carcinoma tissue samples as controls. Gene polymorphisms were genotyped using the Sequenom MassARRAY SNP approach. There was no significant association between the CYP1B1 rs1056836 polymorphism and chemotherapy resistance of ovarian cancer in all genetic models. The results suggest that rs1056836 polymorphism of gene CYP1B1 under obvious selection pressure had a significantly increased risk for ovarian carcinoma. However, it had no significant correlation with chemotherapy resistance of ovarian cancer.
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Breast mass segmentation in mammograms is still a challenging and clinically valuable task. In this paper, we propose an effective and lightweight segmentation model based on convolutional neural networks to automatically segment breast masses in whole mammograms. Specifically, we first developed feature strengthening modules to enhance relevant information about masses and other tissues and improve the representation power of low-resolution feature layers with high-resolution feature maps. Second, we applied a parallel dilated convolution module to capture the features of different scales of masses and fully extract information about the edges and internal texture of the masses. Third, a mutual information loss function was employed to optimise the accuracy of the prediction results by maximising the mutual information between the prediction results and the ground truth. Finally, the proposed model was evaluated on both available INbreast and CBIS-DDSM datasets, and the experimental results indicated that our method achieved excellent segmentation performance in terms of dice coefficient, intersection over union, and sensitivity metrics.