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1.
Wiley Interdiscip Rev RNA ; 15(3): e1851, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38702938

RESUMO

Long noncoding RNAs (lncRNA) are a class of non-coding RNAs greater than 200 bp in length with limited peptide-coding function. The transcription of LINC00152 is derived from chromosome 2p11.2. Many studies prove that LINC00152 influences the progression of various tumors via promoting the tumor cells malignant phenotype, chemoresistance, and immune escape. LINC00152 is regulated by multiple transcription factors and DNA hypomethylation. In addition, LINC00152 participates in the regulation of complex molecular signaling networks through epigenetic regulation, protein interactions, and competitive endogenous RNA (ceRNA). Here, we provide a systematic review of the upstream regulatory factors of LINC00152 expression level in different types of tumors. In addition, we revisit the main functions and mechanisms of LINC00152 as driver oncogene and biomarker in pan-cancer. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Methods > RNA Analyses in Cells RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.


Assuntos
Neoplasias , Oncogenes , RNA Longo não Codificante , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Oncogenes/genética , Regulação Neoplásica da Expressão Gênica
2.
Proteome Sci ; 22(1): 5, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38693542

RESUMO

Hair is an advantageous biological sample due to its recordable, collectable, and storable nature. Hair's primary components are keratin and keratin-associated proteins. Owing to its abundance of cystine, keratin possesses impressive mechanical strength and chemical stability, formed by creating disulfide bonds as crosslinks within the protein peptide chain. Furthermore, keratin is cross-linked with keratin-associated proteins to create a complex network structure that provides the hair with strength and rigidity. Protein extraction serves as the foundation for hair analysis research. Bleaching hair causes damage to the structure between keratin and keratin-associated proteins, resulting in texture issues and hair breakage. This article outlines various physical treatment methods and lysate analysis that enhance the efficiency of hair protein extraction. The PLEE method achieves a three-fold increase in hair protein extraction efficiency when using a lysis solution containing SDS and combining high temperatures with intense shaking, compared to previous methods found in literature. We utilized the PLEE method to extract hair from both normal and damaged groups. Normal samples identified 156-157 proteins, including 51 keratin and keratin-associated proteins. The damaged group consisted of 155-158 identified proteins, of which 48-50 were keratin and keratin-associated proteins. Bleaching did not cause any notable difference in the protein identification of hair. However, it did reduce coverage of keratin and keratin-associated proteins significantly. Our hair protein extraction method provides extensive coverage of the hair proteome. Our findings indicate that bleaching damage results in subpar hair quality due to reduced coverage of protein primary sequences in keratin and keratin-associated proteins.

3.
Cancer Commun (Lond) ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741380

RESUMO

BACKGROUND: Tyrosine phosphorylation of intracellular proteins is a post-translational modification that plays a regulatory role in signal transduction during cellular events. Dephosphorylation of signal transduction proteins caused by protein tyrosine phosphatases (PTPs) contributed their role as a convergent node to mediate cross-talk between signaling pathways. In the context of cancer, PTP-mediated pathways have been identified as signaling hubs that enabled cancer cells to mitigate stress induced by clinical therapy. This is achieved by the promotion of constitutive activation of growth-stimulatory signaling pathways or modulation of the immune-suppressive tumor microenvironment. Preclinical evidences suggested that anticancer drugs will release their greatest therapeutic potency when combined with PTP inhibitors, reversing drug resistance that was responsible for clinical failures during cancer therapy. AREAS COVERED: This review aimed to elaborate recent insights that supported the involvement of PTP-mediated pathways in the development of resistance to targeted therapy and immune-checkpoint therapy. EXPERT OPINION: This review proposed the notion of PTP inhibition in anticancer combination therapy as a potential strategy in clinic to achieve long-term tumor regression. Ongoing clinical trials are currently underway to assess the safety and efficacy of combination therapy in advanced-stage tumors.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38705722

RESUMO

Epidermal melanin unit integrity is crucial for skin homeostasis and pigmentation. Epidermal growth factor (EGF) receptor (EGFR) is a pivotal player in cell growth, wound healing, and maintaining skin homeostasis. However, its influence on skin pigmentation is relatively unexplored. This study investigates the impact and underlying mechanisms of EGFR inhibitors on skin pigmentation. We evaluated EGF and EGFR expression in various skin cells using quantitative real-time PCR, Western blot, and immunofluorescence. EGF and EGFR were predominantly expressed in epidermal keratinocytes, and treatment with the EGFR tyrosine kinase inhibitors (EGFR-TKIs) gefitinib and PD153035 significantly increased stem cell factor (SCF) and endothelin-1 (ET-1) expression in cultured keratinocytes. Enhanced melanocyte migration and proliferation were observed in co-culture, as evidenced by time-lapse live imaging and single-cell tracking assays. Furthermore, topical application of gefitinib to guinea pig dorsal skin induced increased pigmentation and demonstrated efficacy in mitigating rhododendrol-induced leukoderma. Suppression of EGF signaling indirectly enhanced skin pigmentation by upregulating SCF and ET-1 in epidermal keratinocytes. This novel mechanism highlights the pivotal role of EGF signaling in regulating skin pigmentation, and topical EGFR-TKI therapy at an appropriate dose may be a promising approach for depigmentation disorder management.

5.
Cancer Metab ; 12(1): 14, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38755702

RESUMO

BACKGROUND: It is well established that hypercholesterolemia increases the risk of atherosclerosis, especially because it reduces the availability of nitric oxide (NO). However, the relationship between hypercholesterolemia and NO in regulating colorectal cancer development and progression remains unknown. METHODS: We conducted bioinformatics analysis, qRT-PCR, ChIP-qPCR assays, luciferase report assays, clonogenic survival assays, and multiple mouse models to investigate the function and mechanism of hypercholesterolemia in regulating NO signaling. Additionally, NOS inhibitors were used to evaluate the potential of therapeutic strategy in anti-tumor response. RESULTS: Here, we show that oxidized low-density lipoprotein (oxLDL) cholesterol and its receptor LOX-1 are essential for hypercholesterolemia-induced colorectal tumorigenesis. Mechanically, the oxLDL promotes the oxidant stress-dependent induction of hypoxia signaling to transcriptionally up-regulate NO synthase (NOS) especially NOS1 expression in colorectal cancer (CRC) cells. More importantly, our results suggested that selective inhibition of NOS1 with its specific inhibitor Nω-Propyl-L-arginine is a suitable therapeutic strategy for hypercholesterolemia-related CRC with both efficacy and toxicity reduction. CONCLUSIONS: Our findings established that hypercholesterolemia induces the oxidant stress-dependent induction of hypoxia signaling to transcriptionally up-regulate NOS1 expression in CRC cells, and the clinically applicable NOS1 inhibitor Nω-Propyl-L-arginine represents an effective therapeutic strategy for hypercholesterolemia-related CRC.

6.
Curr Med Sci ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748366

RESUMO

OBJECTIVE: This study aimed to examine the role of long non-coding RNA PCED1B antisense RNA 1 (PCED1B-AS1) in the development of hepatocellular carcinoma (HCC). METHODS: A total of 62 pairs of HCC tissues and adjacent non-tumor tissues were obtained from 62 HCC patients. The interactions of PCED1B-AS1 and microRNA-34a (miR-34a) were detected by dual luciferase activity assay and RNA pull-down assay. The RNA expression levels of PCED1B-AS1, miR-34a and CD44 were detected by RT-qPCR, and the protein expression level of CD44 was determined by Western blotting. The cell proliferation was detected by cell proliferation assay, and the cell invasion and migration by transwell invasion assay. The HCC tumor growth after PCED1B-AS1 was downregulated was determined by in vivo animal study. RESULTS: PCED1B-AS1 was highly expressed in HCC tissues, which was associated with poor survival of HCC patients. Furthermore, PCED1B-AS1 interacted with miR-34a in HCC cells, but they did not regulate the expression of each other. Additionally, PCED1B-AS1 increased the expression level of CD44, which was targeted by miR-34a. The cell proliferation and invasion assay revealed that miR-34a inhibited the proliferation and invasion of HCC in vitro, while CD44 exhibited the opposite effects. Furthermore, PCED1B-AS1 suppressed the role of miR-34a. Moreover, the knockdown of PCED1B-AS1 repressed the HCC tumor growth in nude mice in vivo. CONCLUSION: PCED1B-AS1 may play an oncogenic role by regulating the miR-34a/CD44 axis in HCC.

7.
Aging Dis ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38607734

RESUMO

Osteoporosis is an age-related, systemic skeletal disease that poses a significant public health challenge in contemporary society. Development at the epigenetic level is emerging as an important pathogenic mechanism of osteoporosis. Despite indications of a robust association between DNA methylation and osteoporosis development, a comprehensive understanding of the specific role of DNA methylation in osteoporosis remains limited. In this study, significant bone loss was detected at the beginning of eight weeks of age in mouse models of premature aging (SHJHhr mice). We identified a notable upregulation of DNA methyltransferase 3b/3l (Dnmt3b/l) and downregulation of ten eleven translocation dioxygenase 1 (Tet1) in bone marrow mesenchymal stem cells (BMSCs) isolated from SHJHhr mice, along with an increase in the overall 5-methylcytosine (5mC) levels. Moreover, methylation capture sequencing revealed genomic hypermethylation in SHJHhr mice BMSCs. Integrated methylome and transcriptome analyses revealed several crucial methylated genes and networks that are potentially associated with osteoporosis development. Notably, elevated methylation levels of genes linked to the Wnt signaling pathway, particularly bone morphogenetic protein 2 (Bmp2) and fibroblast growth factor receptor (Fgfr2), appeared to compromise the osteogenic differentiation potential of BMSCs. Concurrently, DNA methyltransferase inhibitors attenuated the methylation of the promoter regions of Bmp2 and Fgfr2 and rescued the osteogenic differentiation potential of the BMSCs from SHJHhr mice. In summary, our study provides novel insights into the role of DNA methylation in the development of osteoporosis and suggests promising prospects for employing epigenetic interventions to manage osteoporosis.

8.
J Cell Mol Med ; 28(8): e18309, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613345

RESUMO

There are hundreds of prognostic models for ovarian cancer. These genes are based on different gene classes, and there are many ways to construct the models. Therefore, this paper aims to build the most stable prognostic evaluation system known to date through 101 machine learning strategies. We combined 101 algorithm combinations with 10 machine learning algorithms to create antigen presentation-associated genetic markers (AIDPS) with outstanding precision and steady performance. The inclusive set of algorithms comprises the elastic network (Enet), Ridge, stepwise Cox, Lasso, generalized enhanced regression model (GBM), random survival forest (RSF), supervised principal component (SuperPC), Cox partial least squares regression (plsRcox), survival support vector machine (Survival-SVM). Then, in the train cohort, the prediction model was fitted using a leave-one cross-validation (LOOCV) technique, which involved 101 different possible combinations of prognostic genes. Seven validation data sets (GSE26193, GSE26712, GSE30161, GSE63885, GSE9891, GSE140082 and ICGC_OV_AU) were compared and analysed, and the C-index was calculated. Finally, we collected 32 published ovarian cancer prognostic models (including mRNA and lncRNA). All data sets and prognostic models were subjected to a univariate Cox regression analysis, and the C-index was calculated to demonstrate that the antigen presentation process should be the core criterion for evaluating ovarian cancer prognosis. In a univariate Cox regression analysis, 22 prognostic genes were identified based on the expression profiles of 283 genes involved in antigen presentation and the intersection of genes (p < 0.05). AIDPS were developed by our machine learning-based integration method, which was applied to these 22 genes. One hundred and one prediction models are fitted using the LOOCV framework, and the C-index is calculated for each model across all validation sets. Interestingly, RSF + Lasso was the best model overall since it had the greatest average C-index and the highest C-index of any combination of models tested on the validated data sets. In comparing external cohorts, we found that the C-index correlated AIDPS method using the RSF + Lasso method in 101 prediction models was in contrast to other features. Notably, AIDPS outperformed the vast majority of models across all data sets. Antigen-presenting anti-tumour immune pathways can be used as a representative gene set of ovarian cancer to track the prognosis of patients with cancer. The antigen-presenting model obtained by the RSF + Lasso method has the best C-INDEX, which plays a key role in developing antigen-presenting targeted drugs in ovarian cancer and improving the treatment outcome of patients.


Assuntos
Apresentação de Antígeno , Neoplasias Ovarianas , Humanos , Feminino , Apresentação de Antígeno/genética , Neoplasias Ovarianas/genética , Algoritmos , Sistemas de Liberação de Medicamentos
9.
Saudi Med J ; 45(4): 369-378, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38657990

RESUMO

OBJECTIVES: To examine the risk factors for severe bronchopulmonary dysplasia (BPD) in a cohort of very preterm infants (VPIs) in China, as BPD is common among VPIs and associated with a high mortality rate. METHODS: In this multicenter retrospective study, medical records from infants with BPD born at gestation age (GA) of <32 weeks with birth weight (BW) of <1,500 grams (g) in 7 regions of China were included. The cohort was stratified into different BPD severity groups based on their fraction of inspired oxygen requirement at a modified GA of 36 weeks or post discharge. Risk factors were identified using logistic regression analysis. RESULTS: A significant inverse correlation was revealed between BPD severity and both GA and BW (p<0.001). Independent risk factors for severe BPD (sBPD) were identified as invasive mechanical ventilation (≥7d), multiple blood transfusion (≥3), nosocomial infection (NI), hemodynamically significant patent ductus arteriosus (hsPDA), delayed initiation of enteral nutrition, and longer time to achieve total caloric intake of 110 kcal/kg. Conversely, administration of antenatal steroids was associated with reduced risk of sBPD. CONCLUSION: Our study not only reaffirmed the established risk factors of low GA and BW for sBPD in VPIs, but also identified additional, potentially modifiable risk factors. Further research is warranted to explore whether intervention in these modifiable factors might reduce the risk of sBPD.Clinical Trial Reg. No.: ChiCTR1900023418.


Assuntos
Displasia Broncopulmonar , Humanos , Displasia Broncopulmonar/epidemiologia , Fatores de Risco , Recém-Nascido , China/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Recém-Nascido Prematuro , Índice de Gravidade de Doença , Idade Gestacional , Lactente Extremamente Prematuro , Estudos de Coortes , Respiração Artificial , Permeabilidade do Canal Arterial/epidemiologia , Recém-Nascido de muito Baixo Peso , População do Leste Asiático
10.
Biomolecules ; 14(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38672418

RESUMO

The post-translational modifications (PTMs) of proteins play a crucial role in increasing the functional diversity of proteins and are associated with the pathogenesis of various diseases. This review focuses on a less explored PTM called citrullination, which involves the conversion of arginine to citrulline. This process is catalyzed by peptidyl arginine deiminases (PADs). Different members of the PAD family have distinct tissue distribution patterns and functions. Citrullination is a post-translational modification of native proteins that can alter their structure and convert them into autoantigens; thus, it mediates the occurrence of autoimmune diseases. CD4+ T cells, including Th1, Th2, and Th17 cells, are important immune cells involved in mediating autoimmune diseases, allergic reactions, and tumor immunity. PADs can induce citrullination in CD4+ T cells, suggesting a role for citrullination in CD4+ T cell subset differentiation and function. Understanding the role of citrullination in CD4+ T cells may provide insights into immune-related diseases and inflammatory processes.


Assuntos
Linfócitos T CD4-Positivos , Citrulinação , Humanos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Animais , Doenças Autoimunes/metabolismo , Doenças Autoimunes/imunologia , Desiminases de Arginina em Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Citrulina/metabolismo , Arginina/metabolismo
11.
J Mater Chem B ; 12(13): 3292-3306, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38502068

RESUMO

The regeneration and repair of diabetic wounds, especially those including bacterial infection, have always been difficult and challenging using current treatment. Herein, an effective strategy is reported for constructing glucose-responsive functional hydrogels using nanocomposites as nodes. In fact, tannic acid (TA)-modified ceria nanocomposites (CNPs) and a zinc metal-organic framework (ZIF-8) were employed as nodes. Subsequent crosslinking with 3-acrylamidophenylboronic acid achieved functional nanocomposite-hydrogels (TA@CN gel, TA@ZMG gel) by radical-mediated polymerization. Compared with a simple physically mixed hydrogel system, the mechanical properties of TA@CN gel and TA@ZMG gel are significantly enhanced due to the intervention of the nanocomposite nodes. In addition, this kind of nanocomposite hydrogel can realize the programmed loading of drugs and release of drugs in response to glucose/PH, to coordinate and promote its application in the regeneration and repair of diabetic wounds and infected diabetic wounds. Specifically, TA@CN gel can remove reactive oxygen species and generate oxygen through its various enzymatic activities. At the same time, it can effectively promote neovascularization, thus promoting the regeneration and repair of diabetic wounds. Furthermore, glucose oxidase-loaded TA@ZMG gel exhibits glucose response and pH-regulating functions, triggering programmed metformin (Met) release by degrading the metal-organic framework (MOF) backbone. It also exhibited additional synergistic effects of antibacterial activity, hair regeneration and systemic blood glucose regulation, which make it suitable for the repair of more complex infected diabetic wounds. Overall, this novel nanocomposite-mediated hydrogel holds great potential as a biomaterial for the healing of chronic diabetic wounds, opening up new avenues for further biomedical applications.


Assuntos
Diabetes Mellitus , Estruturas Metalorgânicas , Nanocompostos , Polifenóis , Hidrogéis , Nanogéis , Glucose
12.
Transl Cancer Res ; 13(2): 1188-1195, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38482415

RESUMO

Background: CD5-positive (CD5+) non-germinal center B-cell-like diffuse large B-cell lymphoma (non-GCB DLBCL) is heterogeneous with a poor prognosis. For refractory DLBCL, the median overall survival was only 6.3 months. Therefore, there is a need for approaches to elongate the survival in this subgroup of relapsed DLBCL patients. Case Description: Here, we present a rare case of a 72-year-old patient with stage IV CD5+ non-GCB DLBCL with myeloid differentiation primary response 88 (MYD88) and cluster of differentiation 79B (CD79B) comutations. Zanubrutinib and rituximab therapy was initially administered until disease progression. Subsequently, zanubrutinib plus rituximab together with attenuated standard chemotherapy (miniCHOP) was applied and a notable response was observed. The patient tolerated the treatment well and exhibited a complete response in lung for about 5 months. Afterwards, the patients experienced relapse in the brain and started programmed death protein 1 (PD-1) regimens of toripalimab plus lenalidomide, which also exhibited a good response with decreased lesions in brain after half-year treatment. However, the patient experienced relapse again in the brain 3 months later and started chemotherapy with methotrexate plus rituximab. The patient had survived for over 2 years since the initial diagnosis of stage IV DLBCL and has continued to survive after experiencing a relapse in the brain for approximately 11 months till now. Conclusions: These findings suggest that toripalimab may be a new therapeutic option for central nervous system recurrence in refractory CD5+ DLBCL with MYD88 and CD79B comutation. Further clinical trials are warranted to confirm these results.

13.
Front Pediatr ; 12: 1341221, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510082

RESUMO

Background: Hyperglycemia in pregnancy (HGP) has generally been considered a risk factor associated with adverse outcomes in offspring, but its impact on the short-term outcomes of very preterm infants remains unclear. Methods: A secondary analysis was performed based on clinical data collected prospectively from 28 hospitals in seven regions of China from September 2019 to December 2020. According to maternal HGP, all infants were divided into the HGP group or the non-HGP group. A propensity score matching analysis was used to adjust for confounding factors, including gestational age, twin or multiple births, sex, antenatal steroid administration, delivery mode and hypertensive disorders of pregnancy. The main complications and the short-term growth status during hospitalization were evaluated in the HGP and non-HGP groups. Results: A total of 2,514 infants were eligible for analysis. After matching, there were 437 infants in the HGP group and 874 infants in the non-HGP group. There was no significant difference between the two groups in main complications including respiratory distress syndrome, bronchopulmonary dysplasia, necrotizing enterocolitis, retinopathy of prematurity, patent ductus arteriosus, culture positive sepsis, intraventricular hemorrhage, periventricular leukomalacia, anemia, feeding intolerance, metabolic bone disease of prematurity, or parenteral nutrition-associated cholestasis. The incidences of extrauterine growth retardation and increased growth retardation for weight and head circumference in the non-HGP group were all higher than those in the HGP group after matching (P < 0.05). Conclusions: HGP did not worsen the short-term outcomes of the surviving very preterm infants, as it did not lead to a higher risk of the main neonatal complications, and the infants' growth improved during hospitalization.

14.
Front Pharmacol ; 15: 1335374, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510653

RESUMO

Background: Previous studies have documented important roles for microRNA-147 (miR-147) in inflammation, radiation-induced injury, cancer, and a range of other diseases. Murine lungs exhibit high levels of miRNA, mRNA, and lncRNA expression. However, very little research to date has focused on the lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) networks associated with miR-147, and the regulation of lncRNAs and miRNAs in this setting remains poorly understood. Methods: After establishing a miR-147-/- model mouse, samples of lung tissue were harvested for RNA-sequencing, and differentially expressed lncRNAs, miRNAs, and mRNAs were identified. The miRNA targets of these lncRNAs and the identified miRNAs were first overlapped to facilitate the prediction of target mRNAs, with analyses then examining the overlap between these targets and mRNAs that were differentially expressed. Then, these target mRNAs were subjected to pathway enrichment analyses. These results were ultimately used to establish a miR-147-related ceRNA network. Results: Relative to wild-type mice, the lungs of miR-147-/- mice exhibited 91, 43, and 71 significantly upregulated lncRNAs, miRNAs, and mRNAs, respectively, together with 114, 31, and 156 that were significantly downregulated. The lncRNA-miRNA-mRNA network established based on these results led to the identification of Kcnh6 as a differentially expressed hub gene candidate and enabled the identification of a range of regulatory relationships. KEGG pathway enrichment showed that the mRNA targets of differentially expressed lncRNAs and miRNAs in the mice were associated with tumor-related signaling, endometrial cancer, bladder cancer, and ErbB signaling. Conclusion: These results suggest that the identified ceRNA network in miR-147-/- mice shapes tumor-associated signaling activity, with miR-147 potentially regulating various lncRNAs and miRNAs through Kcnh6, ultimately influencing tumorigenesis. Future studies of the lncRNA, miRNA, and mRNA regulatory targets shown to be associated with miR-147 in the present study may ultimately lead to the identification of novel clinically relevant targets through which miR-147 shapes the pathogenesis of cancer and other diseases.

15.
Appl Environ Microbiol ; 90(3): e0225523, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38415602

RESUMO

Flavoprotein monooxygenases catalyze reactions, including hydroxylation and epoxidation, involved in the catabolism, detoxification, and biosynthesis of natural substrates and industrial contaminants. Among them, the 6-hydroxy-3-succinoyl-pyridine (HSP) monooxygenase (HspB) from Pseudomonas putida S16 facilitates the hydroxylation and C-C bond cleavage of the pyridine ring in nicotine. However, the mechanism for biodegradation remains elusive. Here, we refined the crystal structure of HspB and elucidated the detailed mechanism behind the oxidative hydroxylation and C-C cleavage processes. Leveraging structural information about domains for binding the cofactor flavin adenine dinucleotide (FAD) and HSP substrate, we used molecular dynamics simulations and quantum/molecular mechanics calculations to demonstrate that the transfer of an oxygen atom from the reactive FAD peroxide species (C4a-hydroperoxyflavin) to the C3 atom in the HSP substrate constitutes a rate-limiting step, with a calculated reaction barrier of about 20 kcal/mol. Subsequently, the hydrogen atom was rebounded to the FAD cofactor, forming C4a-hydroxyflavin. The residue Cys218 then catalyzed the subsequent hydrolytic process of C-C cleavage. Our findings contribute to a deeper understanding of the versatile functions of flavoproteins in the natural transformation of pyridine and HspB in nicotine degradation.IMPORTANCEPseudomonas putida S16 plays a pivotal role in degrading nicotine, a toxic pyridine derivative that poses significant environmental challenges. This study highlights a key enzyme, HspB (6-hydroxy-3-succinoyl-pyridine monooxygenase), in breaking down nicotine through the pyrrolidine pathway. Utilizing dioxygen and a flavin adenine dinucleotide cofactor, HspB hydroxylates and cleaves the substrate's side chain. Structural analysis of the refined HspB crystal structure, combined with state-of-the-art computations, reveals its distinctive mechanism. The crucial function of Cys218 was never discovered in its homologous enzymes. Our findings not only deepen our understanding of bacterial nicotine degradation but also open avenues for applications in both environmental cleanup and pharmaceutical development.


Assuntos
Oxigenases de Função Mista , Nicotina , Succinatos , Oxigenases de Função Mista/metabolismo , Nicotina/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Flavoproteínas/metabolismo , Hidroxilação , Piridinas/metabolismo
16.
J Transl Med ; 22(1): 144, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38336780

RESUMO

BACKGROUND: Neoantigens have emerged as a promising area of focus in tumor immunotherapy, with several established strategies aiming to enhance their identification. Human leukocyte antigen class I molecules (HLA-I), which present intracellular immunopeptides to T cells, provide an ideal source for identifying neoantigens. However, solely relying on a mutation database generated through commonly used whole exome sequencing (WES) for the identification of HLA-I immunopeptides, may result in potential neoantigens being missed due to limitations in sequencing depth and sample quality. METHOD: In this study, we constructed and evaluated an extended database for neoantigen identification, based on COSMIC mutation database. This study utilized mass spectrometry-based proteogenomic profiling to identify the HLA-I immunopeptidome enriched from HepG2 cell. HepG2 WES-based and the COSMIC-based mutation database were generated and utilized to identify HepG2-specific mutant immunopeptides. RESULT: The results demonstrated that COSMIC-based database identified 5 immunopeptides compared to only 1 mutant peptide identified by HepG2 WES-based database, indicating its effectiveness in identifying mutant immunopeptides. Furthermore, HLA-I affinity of the mutant immunopeptides was evaluated through NetMHCpan and peptide-docking modeling to validate their binding to HLA-I molecules, demonstrating the potential of mutant peptides identified by the COSMIC-based database as neoantigens. CONCLUSION: Utilizing the COSMIC-based mutation database is a more efficient strategy for identifying mutant peptides from HLA-I immunopeptidome without significantly increasing the false positive rate. HepG2 specific WES-based database may exclude certain mutant peptides due to WES sequencing depth or sample heterogeneity. The COSMIC-based database can effectively uncover potential neoantigens within the HLA-I immunopeptidomes.


Assuntos
Antígenos de Neoplasias , Bases de Dados Genéticas , Antígenos de Histocompatibilidade Classe I , Linfócitos T , Humanos , Antígenos de Neoplasias/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Mutação/genética , Peptídeos/química
17.
Sheng Wu Gong Cheng Xue Bao ; 40(2): 321-336, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38369824

RESUMO

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer. Currently, chemotherapy remains to be the primary treatment for TNBC, but drug resistance is common while patient prognosis is poor. With the development of proteomics technology, phosphoproteomics research has made great progress and has been widely used in the study of tumor mechanism, diagnosis and treatment. Similarly, phosphoproteomics plays a significant role in the studies of the occurrence, development, targeted therapy, and drug resistance mechanisms of TNBC. This article summarizes the research progress of phosphoproteomics in TNBC, with the aim to facilitate the research on the mechanism and treatment of TNBC based on phosphoproteomics.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Prognóstico , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Feminino
18.
PLoS One ; 19(2): e0297939, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38363737

RESUMO

BACKGROUND: The RESCUE BT2 trial recently showcased the efficacy of tirofiban in treating acute ischemic stroke (AIS) without large or medium-sized vessel occlusion. To further assess the value of tirofiban from the perspectives of Chinese and US healthcare system, a study was conducted to evaluate its cost-effectiveness. METHODS: A hybrid model, integrating a short-term decision tree with a long-term Markov model, was developed to assess cost-effectiveness between tirofiban and aspirin for stroke patients without large or medium-sized vessel occlusion. Efficacy data for tirofiban was sourced from the RESCUE BT2 trial, while cost information was derived from published papers. Outcomes measured included respective cost, effectiveness, and incremental cost-effectiveness ratio (ICER). We conducted a one-way sensitivity analysis to assess the robustness of the results. Additionally, we performed probabilistic sensitivity analysis (PSA) through 10,000 Monte Carlo simulations to evaluate the uncertainties associated with the results. RESULTS: The study revealed that tirofiban treatment in AIS patients without large or medium-sized vessel occlusion led to a considerable reduction of 2141 Chinese Yuan (CNY) in total cost, along with a lifetime gain of 0.14 quality-adjusted life years (QALYs). In the US settings, tirofiban also exhibited a lower cost ($197,055 versus $201,984) and higher effectiveness (4.15 QALYs versus 4.06 QALYs) compared to aspirin. One-way sensitivity analysis revealed that post-stroke care costs and stroke utility had the greatest impact on ICER fluctuation in both Chinese and US settings. However, these variations did not exceed the willingness-to-pay threshold. PSA demonstrated tirofiban's superior acceptability over aspirin in over 95% of potential scenarios. CONCLUSION: Tirofiban treatment for AIS without large or medium-sized vessel occlusion appeared dominant compared to aspirin in both China and the US.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , AVC Isquêmico/tratamento farmacológico , Tirofibana/uso terapêutico , Análise Custo-Benefício , Acidente Vascular Cerebral/tratamento farmacológico , Aspirina/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida
19.
Mol Cancer ; 23(1): 22, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38262996

RESUMO

Eukaryotic cells engage in autophagy, an internal process of self-degradation through lysosomes. Autophagy can be classified as selective or non-selective depending on the way it chooses to degrade substrates. During the process of selective autophagy, damaged and/or redundant organelles like mitochondria, peroxisomes, ribosomes, endoplasmic reticulum (ER), lysosomes, nuclei, proteasomes, and lipid droplets are selectively recycled. Specific cargo is delivered to autophagosomes by specific receptors, isolated and engulfed. Selective autophagy dysfunction is closely linked with cancers, neurodegenerative diseases, metabolic disorders, heart failure, etc. Through reviewing latest research, this review summarized molecular markers and important signaling pathways for selective autophagy, and its significant role in cancers. Moreover, we conducted a comprehensive analysis of small-molecule compounds targeting selective autophagy for their potential application in anti-tumor therapy, elucidating the underlying mechanisms involved. This review aims to supply important scientific references and development directions for the biological mechanisms and drug discovery of anti-tumor targeting selective autophagy in the future.


Assuntos
Autofagia , Neoplasias , Humanos , Autofagossomos , Núcleo Celular , Descoberta de Drogas
20.
Int Med Case Rep J ; 17: 23-29, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38223534

RESUMO

Background: Multiple primary cancer (MPC) refers to the presence of more than one cancer in an individual. Triple primary malignancies are uncommon. Case: We report the case of a 50-year-old postmenopausal woman in our gynecology department, diagnosed with endometrial cancer, ovarian cancer, and unilateral breast cancer. She carried germline mutations in BRCA2, PALB2, and RECQL4, along with a somatic pathogenic variant in TP53. Endometrial cancer patients harboring germline pathogenic variants in BRCA2 exhibit a heightened risk of ovarian and breast cancer. BRCA2 is known to play a role in the development of ovarian and breast cancer, while PALB2 is identified as a gene associated with breast cancer susceptibility. RECQL4 has been linked to breast cancer, cervical cancer, and other tumors. Conclusion: Genetic testing may be imperative for identifying MPC in endometrial cancer patients. For individuals with BRCA2 and other gene pathogenic variants, routine examination and monitoring of the endometrium, ovaries, breasts, and other sites prone to polygenic cancer are recommended.

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