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1.
Foods ; 13(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39272522

RESUMO

Folates, a crucial B-group vitamin, serve as a significant functional food supplement. Nevertheless, considerable obstacles persist in improving folates stability in liquid products. In this study, folic acid (FA) and 5-methyltetrahydrofolate (MTFA), two approved sources of folates, were encapsulated with sodium caseinate (NaCas) to enhance their stability. The protective effect of NaCas on folate molecules was investigated using experimental and computational methods. Meanwhile, the influence of divalent calcium ion (Ca2+) on the properties of the NaCas-MTFA complex was examined to evaluate the potential application of calcium 5-methyltetrahydrofolate (CaMTFA). Fluorescence tests showed both folates had static quenching behavior and bound to NaCas with a binding constant of 104-105 M-1. Hydrophobic interactions were crucial in NaCas-FA complex formation, while hydrogen bonding drove NaCas-MTFA binding. The encapsulation of caseinate notably slowed down the degradation of folates under both light and dark conditions. Moreover, the addition of a low concentration of Ca2+ did not adversely impact the binding mechanism of the NaCas-MTFA complex or the degradation curve of MTFA. The results of this study could serve as a valuable resource for the utilization of caseinates in incorporating folates, specifically MTFA, in the creation of natural liquid dietary supplements.

2.
J Clin Transl Hepatol ; 12(6): 562-570, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38974956

RESUMO

Background and Aims: Age-related mosaic chromosomal alterations (mCAs) detected from genotyping of blood-derived DNA are structural somatic variants that indicate clonal hematopoiesis. This study aimed to investigate whether mCAs contribute to the risk of cirrhosis and modify the effect of a polygenic risk score (PRS) on cirrhosis risk prediction. Methods: mCA call sets of individuals with European ancestry were obtained from the UK Biobank. The PRS was constructed based on 12 susceptible single-nucleotide polymorphisms for cirrhosis. Cox proportional hazard models were applied to evaluate the associations between mCAs and cirrhosis risk. Results: Among 448,645 individuals with a median follow-up of 12.5 years, we identified 2,681 cases of cirrhosis, 1,775 cases of compensated cirrhosis, and 1,706 cases of decompensated cirrhosis. Compared to non-carriers, individuals with copy-neutral loss of heterozygosity mCAs had a significantly increased risk of cirrhosis (hazard ratio (HR) 1.42, 95% confidence interval (CI) 1.12-1.81). This risk was higher in patients with expanded cell fractions of mCAs (cell fractions ≥10% vs. cell fractions <10%), especially for the risk of decompensated cirrhosis (HR 2.03 [95% CI 1.09-3.78] vs. 1.14 [0.80-1.64]). In comparison to non-carriers of mCAs with low genetic risk, individuals with expanded copy-neutral loss of heterozygosity and high genetic risk showed the highest cirrhosis risk (HR 5.39 [95% CI 2.41-12.07]). Conclusions: The presence of mCAs is associated with increased susceptibility to cirrhosis risk and could be combined with PRS for personalized cirrhosis risk stratification.

3.
PLoS One ; 19(7): e0306772, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38976673

RESUMO

The objective of this meta-epidemiological study was to develop a rating that captures participants' motivation at the study level in digital health intervention (DHI) randomised controlled trials (RCTs). The rating was used to investigate whether participants' motivation is associated with the effect estimates in DHI RCTs for cancer patients. The development of the rating was based on a bottom-up approach involving the collection of information that captures participants' baseline motivation in empirical studies from the Smartphone-RCCT Database. We specified three indicators for rating: indicator 1 captures whether the study team actively selects or enhances the motivation of the potential study participants; indicator 2 captures the study participants' active engagement before the treatment allocation; and indicator 3 captures the potential bond and trust between the study participants and the person/institution referring to the study. The rating of each indicator and the overall rating varies between high motivation, moderate motivation, and low motivation. We applied the rating across 27 DHI RCTs with cancer patients. We performed meta-regression analysis to examine the effect of patient motivation on quality of life (QoL), psychological outcomes, and attrition. The intraclass correlation coefficient (ICC) indicated moderate to poor inter-rater reliability. The meta-regression showed that cancer patients' overall motivation before engaging in the intervention was associated with the treatment effect of QoL. Patient motivation was not found to be associated with psychological outcomes or attrition. Subgroup analyses revealed that the clinical effects of DHIs were more prevalent in the high-motivation subgroups, whereas the low-motivation subgroups were unlikely to show intervention benefits. The likelihood of dropouts from DHIs seems to be especially high among the low-bond (indicator 3) subgroup. We suggest using single indicators since they reflect specific content. Better reporting about baseline motivation is required to enable meaningful interpretations in not only primary studies but also in evidence syntheses.


Assuntos
Motivação , Neoplasias , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Neoplasias/psicologia , Neoplasias/terapia , Neoplasias/epidemiologia , Estudos Epidemiológicos , Telemedicina , Smartphone , Saúde Digital
4.
Mol Carcinog ; 63(9): 1643-1653, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38860603

RESUMO

This study aimed to explore the clinical significance of genomics features including tumor mutation burden (TMB) and copy number alteration (CNA) for advanced EGFR mutant lung cancer. We retrospectively identified 1378 patients with advanced EGFR mutant lung cancer and next-generation sequencing tests from three cohorts. Multiple co-occurring genomics alternations occurred in a large proportion (97%) of patients with advanced EGFR mutant lung cancers. Both TMB and CNA were predictive biomarkers for these patients. A joint analysis of TMB and CNA found that patients with high TMB and high CNA showed worse responses to EGFR-TKIs and predicted worse outcomes. TMBhighCNAhigh, as a high-risk genomic feature, showed predictive ability in most of the subgroups based on clinical characteristics. These patients had larger numbers of metastatic sites, and higher rates of EGFR copy number amplification, TP53 mutations, and cell-cycle gene alterations, which showed more potential survival gain from combination treatment. Furthermore, a nomogram based on genomic features and clinical features was developed to distinguish prognosis. Genomic features could stratify prognosis and guide clinical treatment for patients with advanced EGFR mutant lung cancer.


Assuntos
Variações do Número de Cópias de DNA , Receptores ErbB , Neoplasias Pulmonares , Mutação , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Receptores ErbB/genética , Masculino , Feminino , Prognóstico , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Biomarcadores Tumorais/genética , Genômica/métodos , Inibidores de Proteínas Quinases/uso terapêutico , Nomogramas
5.
J Biomed Res ; : 1-12, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38807427

RESUMO

Epidemiological data is scarce regarding the association between exposure to mixtures of per- and polyfluoroalkyl substances (PFASs) and liver injury in the general populace. The current research used data from the National Health and Nutrition Examination Survey (2009-2018). The PFAS exposure levels were defined by the serum concentrations of PFASs with > 70% detection in samples, namely perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexane sulfonic acid (PFHxS), perfluorodecanoic acid (PFDeA), and perfluorooctane sulfonic acid (PFOS). Liver injury was assessed from two aspects: first, the degree of liver inflammation was determined based on serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutamyltransferase (GGT), and total bilirubin (TBIL) levels; second, the degree of liver fibrosis was determined based on fibrosis-4 (FIB-4) index. We assessed the associations between individual or total PFAS exposure and these outcomes using multivariable linear regression models and logistic regression models, restricted cubic splines, and weighted quantile sum regression. Among the samples of 7484 American adults, the median concentration of PFOS was the highest, followed by PFOA and PFHxS. Using multivariable linear regression, a positive correlation was observed between all PFASs and liver enzymes such as ALT, AST, and TBIL. Additionally, the weighted quantile sum model indicated an overall positive association between the five PFASs and liver injury indicators. For liver function biomarkers and liver fibrosis, PFNA and PFOS were the most heavily weighting chemicals, respectively. Our findings provide new epidemiological evidence indicating a potential association between PFAS exposure and adverse effects on liver injury biomarkers, highlighting the potentially harmful effects of PFAS exposure on liver health.

6.
Int J Med Inform ; 184: 105345, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38309237

RESUMO

OBJECTIVE: Mobile Health (mHealth) refers to using mobile devices to support health. This study aimed to identify specific methodological challenges in systematic reviews (SRs) of mHealth interventions and to develop guidance for addressing selected challenges. STUDY DESIGN AND SETTING: Two-phase participatory research project. First, we sent an online survey to corresponding authors of SRs of mHealth interventions. On a five-category scale, survey respondents rated how challenging they found 24 methodological aspects in SRs of mHealth interventions compared to non-mHealth intervention SRs. Second, a subset of survey respondents participated in an online workshop to discuss recommendations to address the most challenging methodological aspects identified in the survey. Finally, consensus-based recommendations were developed based on the workshop discussion and subsequent interaction via email with the workshop participants and two external mHealth SR authors. RESULTS: We contacted 953 corresponding authors of mHealth intervention SRs, of whom 50 (5 %) completed the survey. All the respondents identified at least one methodological aspect as more or much more challenging in mHealth intervention SRs than in non-mHealth SRs. A median of 11 (IQR 7.25-15) out of 24 aspects (46 %) were rated as more or much more challenging. Those most frequently reported were: defining intervention intensity and components (85 %), extracting mHealth intervention details (71 %), dealing with dynamic research with evolving interventions (70 %), assessing intervention integrity (69 %), defining the intervention (66 %) and maintaining an updated review (65 %). Eleven survey respondents participated in the workshop (five had authored more than three mHealth SRs). Eighteen consensus-based recommendations were developed to address issues related to mHealth intervention integrity and to keep mHealth SRs up to date. CONCLUSION: mHealth SRs present specific methodological challenges compared to non-mHealth interventions, particularly related to intervention integrity and keeping SRs current. Our recommendations for addressing these challenges can improve mHealth SRs.


Assuntos
Projetos de Pesquisa , Telemedicina , Humanos , Consenso , Revisões Sistemáticas como Assunto , Inquéritos e Questionários
7.
Entropy (Basel) ; 25(9)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37761547

RESUMO

The measurement matrix used influences the performance of image reconstruction in compressed sensing. To enhance the performance of image reconstruction in compressed sensing, two different Gaussian random matrices were orthogonalized via Gram-Schmidt orthogonalization, respectively. Then, one was used as the real part and the other as the imaginary part to construct a complex-valued Gaussian matrix. Furthermore, we sparsified the proposed measurement matrix to reduce the storage space and computation. The experimental results show that the complex-valued Gaussian matrix after orthogonalization has better image reconstruction performance, and the peak signal-to-noise ratio and structural similarity under different compression ratios are better than the real-valued measurement matrix. Moreover, the sparse measurement matrix can effectively reduce the amount of calculation.

8.
Cancer Med ; 12(11): 12504-12517, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37226372

RESUMO

PURPOSE: To assess the effectiveness and safety of acupuncture for the prevention of chemotherapy-induced nausea and vomiting (CINV), with a specific intention on exploring sources of between-study variation in treatment effects. METHODS: MEDLINE, EMBASE, Cochrane CENTRAL, CINAHL, Chinese Biomedical Literature Database, VIP Chinese Science and Technology Periodicals Database, China National Knowledge Infrastructure, and Wanfang were searched to identify randomized controlled trials (RCTs) that compared acupuncture to sham acupuncture or usual care (UC). The main outcome is complete control (no vomiting episodes and/or no more than mild nausea) of CINV. GRADE approach was used to rate the certainty of evidence. RESULTS: Thirty-eight RCTs with a total of 2503 patients were evaluated. Acupuncture in addition to UC may increase the complete control of acute vomiting (RR, 1.13; 95% CI, 1.02 to 1.25; 10 studies) and delayed vomiting (RR, 1.47; 95% CI, 1.07 to 2.00; 10 studies) when compared with UC only. No effects were found for all other review outcomes. The certainty of evidence was generally low or very low. None of the predefined moderators changed the overall findings, but in an exploratory moderator analysis we found that an adequate reporting of planned rescue antiemetics might decrease the effect size of complete control of acute vomiting (p = 0.035). CONCLUSION: Acupuncture in addition to usual care may increase the complete control of chemotherapy-induced acute vomiting and delayed vomiting but the certainty of evidence was very low. Well-designed RCTs with larger sample sizes, standardized treatment regimens, and core outcome measures are needed.


Assuntos
Terapia por Acupuntura , Antieméticos , Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/efeitos adversos , Vômito/induzido quimicamente , Vômito/prevenção & controle , Náusea/induzido quimicamente , Náusea/prevenção & controle , Antieméticos/uso terapêutico , Neoplasias/tratamento farmacológico
9.
Liver Int ; 43(6): 1287-1297, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37088982

RESUMO

BACKGROUND & AIMS: Physical activity, sedentary behaviour, and genetic variants have been associated with the nonalcoholic fatty liver disease (NAFLD). However, whether and how the degree of healthy activity patterns may modify the impact of genetic susceptibility on NAFLD remains unknown. METHODS: Behaviour activity factors were determined according to total physical activity (TPA) and sedentary time. The polygenic risk score (PRS) was calculated by variants in PNPLA3, TM6SF2, MBOAT7, and GCKR. Cox regression was used to analyse the associations of genetic and behaviour activity factors with incident NAFLD in the UK Biobank (N = 338 087). RESULTS: During a median follow-up of 12.4 years, 3201 incident NAFLD cases were ascertained. Analyses of TPA and sedentary time simultaneously showed a dose-response association with the risk of NAFLD (ptrend < .001). The association of behaviour activity patterns with NAFLD varied by genetic variants. Of the subjects with high genetic risk, we observed a null protective effect of moderate or high TPA on NAFLD risk, while sitting less than three hours a day significantly decreased the risk of NAFLD (p = 3.50 × 10-4 ). The high genetic risk of NAFLD can also be offset by the combination of moderate physical activity and shorter sedentary time. Moreover, the high genetic risk group has the greatest reduction of 10-year absolute risk (6.95 per 1000 person-years) if reaching both healthy activities. CONCLUSIONS: Moderate-to-high physical activity and favourable sedentary behaviour may be lifestyle modifications in preventing NAFLD, which could offset the harmful effect of predisposing genetic factors.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Bancos de Espécimes Biológicos , Predisposição Genética para Doença , Fígado , Proteínas de Membrana/genética , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/genética , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de Risco , Reino Unido/epidemiologia
10.
Nat Commun ; 14(1): 1810, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37002234

RESUMO

53BP1 promotes nonhomologous end joining (NHEJ) over homologous recombination (HR) repair by mediating inactivation of DNA end resection. Ubiquitination plays an important role in regulating dissociation of 53BP1 from DNA double-strand breaks (DSBs). However, how this process is regulated remains poorly understood. Here, we demonstrate that TRABID deubiquitinase binds to 53BP1 at endogenous level and regulates 53BP1 retention at DSB sites. TRABID deubiquitinates K29-linked polyubiquitination of 53BP1 mediated by E3 ubiquitin ligase SPOP and prevents 53BP1 dissociation from DSBs, consequently inducing HR defects and chromosomal instability. Prostate cancer cells with TRABID overexpression exhibit a high sensitivity to poly (ADP-ribose) polymerase (PARP) inhibitors. Our work shows that TRABID facilitates NHEJ repair over HR during DNA repair by inducing prolonged 53BP1 retention at DSB sites, suggesting that TRABID overexpression may predict HR deficiency and the potential therapeutic use of PARP inhibitors in prostate cancer.


Assuntos
Inibidores de Poli(ADP-Ribose) Polimerases , Neoplasias da Próstata , Masculino , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Mutações Sintéticas Letais , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Reparo do DNA , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Reparo do DNA por Junção de Extremidades , DNA/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo
11.
Cancer Res ; 83(6): 875-889, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36637424

RESUMO

Retinoblastoma (RB) protein can exert tumor suppressor functions even when it becomes phosphorylated. It is thus essential to understand how phosphorylated RB (p-RB) expression and function are regulated. Here, we demonstrated that RING finger domain protein TRIM28 bound and promoted ubiquitination and degradation of CDK4/6-phosphorylated RB protein. SETDB1, a known TRIM28 binding partner, protected p-RB from degradation through the binding of methylated RB by its Tudor domain independent of its methyltransferase activity. SETDB1 was found to be frequently overexpressed due to gene amplification and positively correlated with p-RB in prostate cancer patient specimens. Inhibition of SETDB1 expression using a gene-specific antisense oligonucleotide (ASO) reduced tumor growth but accelerated RB protein degradation, limiting the therapeutic efficacy. However, coadministration of the CDK4/6 inhibitor palbociclib blocked ASO-induced RB degradation and resulted in a much greater cancer-inhibitory effect than each inhibitor alone both in vitro and in vivo. This study identified CDK4/6-dependent, TRIM28-mediated proteasomal degradation as a mechanism of RB inactivation and reveals SETDB1 as a key inhibitor of this process. Our findings suggest that combined targeting of SETDB1 and CDK4/6 represents a viable approach for the treatment of cancers with SETDB1 gene amplification or overexpression. SIGNIFICANCE: The identification of a role for TRIM28 and SETDB1 in regulating CDK4/6-phosphorylated RB stability uncovers a combination strategy using CDK4/6 and SETDB1 inhibition to decrease RB degradation and inhibit cancer growth.


Assuntos
Neoplasias , Humanos , Masculino , Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Fosforilação , Proteína do Retinoblastoma/genética
12.
Ultrason Sonochem ; 88: 106095, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35850035

RESUMO

The current innovative work combines nano-optical sensors with near-infrared spectroscopy for rapid detection and quantification of polyphenols and investigates the potential of the nano-optical sensor based on chemo-selective colorants to detect the dynamic changes in aroma components during the fermentation of tea extract. The procedure examined the influence of different ultrasound-assisted sonication factors on the changes in the consumption rate of polyphenols during the fermentation of tea extract versus non-sonication as a control group. The results showed that the polyphenol consumption rate improved under the ultrasound conditions of 28 kHz ultrasound frequency, 24 min treatment time, and 40 W/L ultrasonic power density. The metal-organic framework based nano-optical sensors reported here have more adsorption sites for enhanced adsorption of the volatile organic compounds. The polystyrene-acrylic microstructure offered specific surface area for the reactants. Besides, the employed porous silica nanospheres with higher porosity administered improved gas enrichment effect. The nano-optical sensor exhibits good performance with a "chromatogram" for the identification of aroma components in the fermentation process of tea extract. The proposed method respectively enhanced the consumption rate of polyphenol by 35.57%, 11.34% and 16.09% under the optimized conditions. Based on the established polyphenol quantitative prediction models, this work demonstrated the feasibility of using a nano-optical sensor to perform in-situ imaging of the fermentation degree of tea extracts subjected to ultrasonic treatment.


Assuntos
Odorantes , Polifenóis , Fermentação , Extratos Vegetais , Polifenóis/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Chá/química
13.
Chem Commun (Camb) ; 58(14): 2383-2386, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35080528

RESUMO

In this study, we identified 3-aminophthalic acid as a new ligand of cereblon (CRBN) E3 ubiquitin ligase and developed a phthalic acid-based O'PROTAC for degradation of the ERG transcription factor. This phthalic acid-based O'PROTAC presented an efficacy in degrading ERG comparable to those displayed by pomalidomide-based ERG O'PROTACs. Moreover, phthalic acid-being more chemically stable and economical than classical immunomodulatory drugs (IMiDs)-represents, as a ligand, a new alternative for the development of PROTACs, especially O'PROTACs.


Assuntos
Ácidos Ftálicos/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Relação Dose-Resposta a Droga , Humanos , Ligantes , Estrutura Molecular , Ácidos Ftálicos/química , Proteólise/efeitos dos fármacos , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
14.
Mol Cancer Res ; 20(1): 62-76, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610962

RESUMO

Although the Sonic hedgehog (SHH) signaling pathway has been implicated in promoting malignant phenotypes of prostate cancer, details on how it is activated and exerts its oncogenic role during prostate cancer development and progression is less clear. Here, we show that GLI3, a key SHH pathway effector, is transcriptionally upregulated during androgen deprivation and posttranslationally stabilized in prostate cancer cells by mutation of speckle-type POZ protein (SPOP). GLI3 is a substrate of SPOP-mediated proteasomal degradation in prostate cancer cells and prostate cancer driver mutations in SPOP abrogate GLI3 degradation. Functionally, GLI3 is necessary and sufficient for the growth and migration of androgen receptor (AR)-positive prostate cancer cells, particularly under androgen-depleted conditions. Importantly, we demonstrate that GLI3 physically interacts and functionally cooperates with AR to enrich an AR-dependent gene expression program leading to castration-resistant growth of xenografted prostate tumors. Finally, we identify an AR/GLI3 coregulated gene signature that is highly correlated with castration-resistant metastatic prostate cancer and predictive of disease recurrence. Together, these findings reveal that hyperactivated GLI3 promotes castration-resistant growth of prostate cancer and provide a rationale for therapeutic targeting of GLI3 in patients with castration-resistant prostate cancer (CRPC). IMPLICATIONS: We describe two clinically relevant mechanisms leading to hyperactivated GLI3 signaling and enhanced AR/GLI3 cross-talk, suggesting that GLI3-specific inhibitors might prove effective to block prostate cancer development or delay CRPC.


Assuntos
Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares , Neoplasias de Próstata Resistentes à Castração/genética , Proteínas Repressoras/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , Proteína Gli3 com Dedos de Zinco/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Mutação , Receptores Androgênicos/metabolismo
15.
Nat Commun ; 12(1): 5779, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599168

RESUMO

Geminin and its binding partner Cdt1 are essential for the regulation of DNA replication. Here we show that the CULLIN3 E3 ubiquitin ligase adaptor protein SPOP binds Geminin at endogenous level and regulates DNA replication. SPOP promotes K27-linked non-degradative poly-ubiquitination of Geminin at lysine residues 100 and 127. This poly-ubiquitination of Geminin prevents DNA replication over-firing by indirectly blocking the association of Cdt1 with the MCM protein complex, an interaction required for DNA unwinding and replication. SPOP is frequently mutated in certain human cancer types and implicated in tumorigenesis. We show that cancer-associated SPOP mutations impair Geminin K27-linked poly-ubiquitination and induce replication origin over-firing and re-replication. The replication stress caused by SPOP mutations triggers replication catastrophe and cell death upon ATR inhibition. Our results reveal a tumor suppressor role of SPOP in preventing DNA replication over-firing and genome instability and suggest that SPOP-mutated tumors may be susceptible to ATR inhibitor therapy.


Assuntos
Geminina/metabolismo , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Complexos Ubiquitina-Proteína Ligase/genética , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Replicação do DNA/genética , Replicação do DNA/fisiologia , Geminina/genética , Humanos , Masculino , Camundongos , Camundongos SCID , Proteínas de Manutenção de Minicromossomo/genética , Proteínas de Manutenção de Minicromossomo/metabolismo , Mutação/genética , Ubiquitinação/genética , Ubiquitinação/fisiologia
16.
Nat Commun ; 12(1): 5716, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588438

RESUMO

Mutations in SPOP E3 ligase gene are reportedly associated with genome-wide DNA hypermethylation in prostate cancer (PCa) although the underlying mechanisms remain elusive. Here, we demonstrate that SPOP binds and promotes polyubiquitination and degradation of histone methyltransferase and DNMT interactor GLP. SPOP mutation induces stabilization of GLP and its partner protein G9a and aberrant upregulation of global DNA hypermethylation in cultured PCa cells and primary PCa specimens. Genome-wide DNA methylome analysis shows that a subset of tumor suppressor genes (TSGs) including FOXO3, GATA5, and NDRG1, are hypermethylated and downregulated in SPOP-mutated PCa cells. DNA methylation inhibitor 5-azacytidine effectively reverses expression of the TSGs examined, inhibits SPOP-mutated PCa cell growth in vitro and in mice, and enhances docetaxel anti-cancer efficacy. Our findings reveal the GLP/G9a-DNMT module as a mediator of DNA hypermethylation in SPOP-mutated PCa. They suggest that SPOP mutation could be a biomarker for effective treatment of PCa with DNA methylation inhibitor alone or in combination with taxane chemotherapeutics.


Assuntos
Metilação de DNA/genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Proteínas Nucleares/genética , Neoplasias da Próstata/genética , Proteínas Repressoras/genética , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA/efeitos dos fármacos , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Supressores de Tumor , Humanos , Masculino , Camundongos , Mutação , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Estabilidade Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Proteínas Repressoras/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Adv Sci (Weinh) ; 8(20): e2102555, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34397171

RESUMO

DNA-binding proteins, including transcription factors (TFs), play essential roles in various cellular processes and pathogenesis of diseases, deeming to be potential therapeutic targets. However, these proteins are generally considered undruggable as they lack an enzymatic catalytic site or a ligand-binding pocket. Proteolysis-targeting chimera (PROTAC) technology has been developed by engineering a bifunctional molecule chimera to bring a protein of interest (POI) to the proximity of an E3 ubiquitin ligase, thus inducing the ubiquitination of POI and further degradation through the proteasome pathway. Here, the development of oligonucleotide-based PROTAC (O'PROTACs), a class of noncanonical PROTACs in which a TF-recognizing double-stranded oligonucleotide is incorporated as a binding moiety of POI is reported. It is demonstrated that O'PROTACs of lymphoid enhancer-binding factor 1 (LEF1) and ETS-related gene (ERG), two highly cancer-related transcription factors, successfully promote degradation of these proteins, impede their transcriptional activity, and inhibit cancer cell growth in vitro and in vivo. The programmable nature of O'PROTACs indicates that this approach is also applicable to destruct other TFs. O'PROTACs not only can serve as a research tool but also can be harnessed as a therapeutic arsenal to target DNA binding proteins for effective treatment of diseases such as cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Fator 1 de Ligação ao Facilitador Linfoide/genética , Neoplasias/genética , Oligonucleotídeos/genética , Humanos , Neoplasias/terapia , Oligonucleotídeos/farmacologia , Complexo de Endopeptidases do Proteassoma/genética , Proteólise/efeitos dos fármacos , Regulador Transcricional ERG/genética , Ubiquitina-Proteína Ligases/genética
18.
Integr Cancer Ther ; 20: 15347354211031650, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34261372

RESUMO

BACKGROUND: Traditional Chinese medicine (TCM) is widely integrated into cancer care in China. An overview in 2011 identified 2384 randomized and non-randomized controlled trials (RCTs, non-RCTs) on TCM for cancer published in the Chinese literature. This article summarizes updated evidence of RCTs on TCM for cancer care. METHODS: We searched 4 main Chinese databases: China National Knowledge Infrastructure, Chinese Scientific Journal Database, SinoMed, and Wanfang. RCTs on TCM used in cancer care were analyzed in this bibliometric study. RESULTS: Of 5834 RCTs (477 157 cancer patients), only 62 RCTs were indexed in MEDLINE. The top 3 cancers treated were lung, stomach, and breast cancer. About 4752 RCTs (81.45%) tested TCM combined with conventional treatment, and 1082 RCTs (18.55%) used TCM alone for treating symptoms and side-effects. Herbal medicine was the most frequently used TCM modality (5087 RCTs; 87.20%). The most frequently reported outcome was symptom improvement (3712 RCTs; 63.63%) followed by quality of life (2725 RCTs; 46.71%), and biomarkers (2384 RCTs; 40.86%). The majority of RCTs (4051; 69.44%) concluded there were beneficial effects using either TCM alone or TCM plus conventional treatment compared with conventional treatment. CONCLUSION: Substantial randomized trials demonstrated different types/stages of cancer were treated by various TCM modalities, alone or in combination with conventional medicine. Further evaluation on the effects and safety of TCM modalities focusing on outcomes such as quality of life is required.


Assuntos
Neoplasias da Mama , Medicamentos de Ervas Chinesas , China , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Humanos , Medicina Tradicional Chinesa , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Sci Adv ; 7(25)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34144977

RESUMO

53BP1 activates nonhomologous end joining (NHEJ) and inhibits homologous recombination (HR) repair of DNA double-strand breaks (DSBs). Dissociation of 53BP1 from DSBs and consequent activation of HR, a less error-prone pathway than NHEJ, helps maintain genome integrity during DNA replication; however, the underlying mechanisms are not fully understood. Here, we demonstrate that E3 ubiquitin ligase SPOP promotes HR during S phase of the cell cycle by excluding 53BP1 from DSBs. In response to DNA damage, ATM kinase-catalyzed phosphorylation of SPOP causes a conformational change in SPOP, revealed by x-ray crystal structures, that stabilizes its interaction with 53BP1. 53BP1-bound SPOP induces polyubiquitination of 53BP1, eliciting 53BP1 extraction from chromatin by a valosin-containing protein/p97 segregase complex. Our work shows that SPOP facilitates HR repair over NHEJ during DNA replication by contributing to 53BP1 removal from chromatin. Cancer-derived SPOP mutations block SPOP interaction with 53BP1, inducing HR defects and chromosomal instability.


Assuntos
Cromatina , Quebras de DNA de Cadeia Dupla , Cromatina/genética , Reparo do DNA por Junção de Extremidades , Replicação do DNA , Proteínas Nucleares , Reparo de DNA por Recombinação , Proteínas Repressoras , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
20.
J Clin Invest ; 131(14)2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34101624

RESUMO

Androgen receptor-positive prostate cancer (PCa) and estrogen receptor-positive luminal breast cancer (BCa) are generally less responsive to immunotherapy compared with certain tumor types such as melanoma. However, the underlying mechanisms are not fully elucidated. In this study, we found that FOXA1 overexpression inversely correlated with interferon (IFN) signature and antigen presentation gene expression in PCa and BCa patients. FOXA1 bound the STAT2 DNA-binding domain and suppressed STAT2 DNA-binding activity, IFN signaling gene expression, and cancer immune response independently of the transactivation activity of FOXA1 and its mutations detected in PCa and BCa. Increased FOXA1 expression promoted cancer immuno- and chemotherapy resistance in mice and PCa and BCa patients. These findings were also validated in bladder cancer expressing high levels of FOXA1. FOXA1 overexpression could be a prognostic factor to predict therapy resistance and a viable target to sensitize luminal PCa, BCa, and bladder cancer to immuno- and chemotherapy.


Assuntos
Regulação Neoplásica da Expressão Gênica/imunologia , Fator 3-alfa Nuclear de Hepatócito/imunologia , Interferons/imunologia , Proteínas de Neoplasias/imunologia , Neoplasias/imunologia , Transdução de Sinais/imunologia , Animais , Feminino , Fator 3-alfa Nuclear de Hepatócito/genética , Humanos , Interferons/genética , Masculino , Camundongos , Proteínas de Neoplasias/genética , Neoplasias/genética , Transdução de Sinais/genética
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