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1.
Am J Pathol ; 194(5): 656-672, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38325552

RESUMO

Idiopathic pulmonary fibrosis is a progressive interstitial lung disease for which there is no curative therapy available. Repetitive alveolar epithelial injury repair, myofibroblast accumulation, and excessive collagen deposition are key pathologic features of idiopathic pulmonary fibrosis, eventually leading to cellular hypoxia and respiratory failure. The precise mechanism driving this complex maladaptive process remains inadequately understood. WD repeat and suppressor of cytokine signaling box containing 1 (WSB1) is an E3 ubiquitin ligase, the expression of which is associated strongly with hypoxia, and forms a positive feedback loop with hypoxia-inducible factor 1α (HIF-1α) under anoxic condition. This study explored the expression, cellular distribution, and function of WSB1 in bleomycin (BLM)-induced mouse lung injury and fibrosis. WSB1 expression was highly induced by BLM injury and correlated with the progression of lung fibrosis. Significantly, conditional deletion of Wsb1 in adult mice ameliorated BLM-induced pulmonary fibrosis. Phenotypically, Wsb1-deficient mice showed reduced lipofibroblast to myofibroblast transition, but enhanced alveolar type 2 proliferation and differentiation into alveolar type 1 after BLM injury. Proteomic analysis of mouse lung tissues identified caveolin 2 as a potential downstream target of WSB1, contributing to BLM-induced epithelial injury repair and fibrosis. These findings unravel a vital role for WSB1 induction in lung injury repair, thus highlighting it as a potential therapeutic target for pulmonary fibrosis.


Assuntos
Fibrose Pulmonar Idiopática , Lesão Pulmonar , Animais , Camundongos , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Miofibroblastos/metabolismo , Lesão Pulmonar/patologia , Proteômica , Pulmão/patologia , Fibrose , Hipóxia/patologia , Fibrose Pulmonar Idiopática/patologia , Bleomicina/toxicidade , Regeneração , Peptídeos e Proteínas de Sinalização Intracelular
2.
Nucleic Acids Res ; 51(14): e78, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37378451

RESUMO

Classic strategies for circular RNA (circRNA) preparation always introduce large numbers of linear transcripts or extra nucleotides to the circularized product. In this study, we aimed to develop an efficient system for circRNA preparation based on a self-splicing ribozyme derived from an optimized Tetrahymena thermophila group Ⅰ intron. The target RNA sequence was inserted downstream of the ribozyme and a complementary antisense region was added upstream of the ribozyme to assist cyclization. Then, we compared the circularization efficiency of ribozyme or flanking intronic complementary sequence (ICS)-mediated methods through the DNMT1, CDR1as, FOXO3, and HIPK3 genes and found that the efficiency of our system was remarkably higher than that of flanking ICS-mediated method. Consequently, the circularized products mediated by ribozyme are not introduced with additional nucleotides. Meanwhile, the overexpressed circFOXO3 maintained its biological functions in regulating cell proliferation, migration, and apoptosis. Finally, a ribozyme-based circular mRNA expression system was demonstrated with a split green fluorescent protein (GFP) using an optimized Coxsackievirus B3 (CVB3) internal ribosome entry site (IRES) sequence, and this system achieved successful translation of circularized mRNA. Therefore, this novel, convenient, and rapid engineering RNA circularization system can be applied for the functional study and large-scale preparation of circular RNA in the future.


Assuntos
RNA Catalítico , RNA Circular , Tetrahymena thermophila , Sequência de Bases , Nucleotídeos/metabolismo , Splicing de RNA , RNA Catalítico/genética , RNA Catalítico/metabolismo , RNA Circular/metabolismo , RNA Mensageiro/metabolismo , Tetrahymena thermophila/genética , Tetrahymena thermophila/metabolismo
3.
Cell Commun Signal ; 21(1): 206, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587464

RESUMO

The heart is a muscular organ that pumps blood throughout the body and is one of the most vital organs in human body. While cardiomyocytes are essential for maintaining the normal function of the heart, a variety of cardiovascular diseases such as coronary artery occlusion, arrhythmia, and myocarditis can lead to cardiomyocyte death, resulting in deterioration of heart function. The adult mammalian heart is incapable of regenerating sufficient cardiomyocytes following cardiac injuries, eventually leading to heart failure and death. Cardiac macrophages are ubiquitously distributed in the healthy heart and accumulated at the site of injury. Macrophages play essential roles in regulating homeostasis and proliferation of cardiomyocyte, promoting electrical conduction, and removing dead cardiomyocytes and debris through direct and indirect cell-cell crosstalk. In this review, we summarize the latest insights into the role of macrophages in maintaining cardiac homeostasis and the macrophage-cardiomyocyte crosstalk in both healthy and injured scenarios. Video Abstract.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Adulto , Humanos , Animais , Miócitos Cardíacos , Homeostase , Macrófagos , Mamíferos
4.
Acta Pharmacol Sin ; 44(10): 2004-2018, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37225844

RESUMO

Doxorubicin is a common chemotherapeutic agent in clinic, but myocardial toxicity limits its use. Fibroblast growth factor (FGF) 10, a multifunctional paracrine growth factor, plays diverse roles in embryonic and postnatal heart development as well as in cardiac regeneration and repair. In this study we investigated the role of FGF10 as a potential modulator of doxorubicin-induced cardiac cytotoxicity and the underlying molecular mechanisms. Fgf10+/- mice and an inducible dominant negative FGFR2b transgenic mouse model (Rosa26rtTA; tet(O)sFgfr2b) were used to determine the effect of Fgf10 hypomorph or blocking of endogenous FGFR2b ligands activity on doxorubicin-induced myocardial injury. Acute myocardial injury was induced by a single injection of doxorubicin (25 mg/kg, i.p.). Then cardiac function was evaluated using echocardiography, and DNA damage, oxidative stress and apoptosis in cardiac tissue were assessed. We showed that doxorubicin treatment markedly decreased the expression of FGFR2b ligands including FGF10 in cardiac tissue of wild type mice, whereas Fgf10+/- mice exhibited a greater degree of oxidative stress, DNA damage and apoptosis as compared with the Fgf10+/+ control. Pre-treatment with recombinant FGF10 protein significantly attenuated doxorubicin-induced oxidative stress, DNA damage and apoptosis both in doxorubicin-treated mice and in doxorubicin-treated HL-1 cells and NRCMs. We demonstrated that FGF10 protected against doxorubicin-induced myocardial toxicity via activation of FGFR2/Pleckstrin homology-like domain family A member 1 (PHLDA1)/Akt axis. Overall, our results unveil a potent protective effect of FGF10 against doxorubicin-induced myocardial injury and identify FGFR2b/PHLDA1/Akt axis as a potential therapeutic target for patients receiving doxorubicin treatment.


Assuntos
Fator 10 de Crescimento de Fibroblastos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Animais , Camundongos , Doxorrubicina , Fator 10 de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição
5.
Appl Microbiol Biotechnol ; 106(24): 8285-8294, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36404357

RESUMO

Current clinical laboratory assays are not sufficient for determining the activity of many specific human proteases yet. In this study, we developed a general approach that enables the determination of activities of caspase-3 based on the proteolytic activation of the engineered zymogen of the recombinant tyrosinase from Verrucomicrobium spinosum (Vs-tyrosinase) by detecting the diphenolase activity in an increase in absorbance at 475 nm. Here, we designed three different zymogen constructs of Vs-tyrosinase, including RSL-pre-pro-TYR, Pre-pro-TYR, and Pro-TYR. The active domain was fused to the reactive site loop (RSL) of α1-proteinase inhibitor and/or its own signal peptide (pre) and/or its own C-terminal domain (pro) via a linker containing a specific caspase-3 cleavage site. Further studies revealed that both RSL peptide and TAT signal peptide were able to inhibit tyrosinase diphenolase activity, in which RSL-pre-pro-TYR had the lowest background signals. Therefore, a specific protease activity such as caspase-3 could be detected when a suitable zymogen was established. Our results could provide a new way to directly detect the activities of key human proteases, for instance, to monitor the efficacy and safety of tumor therapy by determining the activity of apoptosis-related caspase-3 in patients. KEY POINTS: • RSL inhibited the activity of Verrucomicrobium spinosum tyrosinase. • N-pre and C-terminal domain exerted stronger dual inhibition on the Vs-tyrosinase. • The activity of caspase-3 could be measured by the zymogen activation system.


Assuntos
Proteínas de Bactérias , Ensaios Enzimáticos Clínicos , Precursores Enzimáticos , Monofenol Mono-Oxigenase , Peptídeo Hidrolases , Verrucomicrobia , Humanos , Caspase 3/análise , Precursores Enzimáticos/química , Precursores Enzimáticos/genética , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/genética , Sinais Direcionadores de Proteínas , Verrucomicrobia/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Domínios Proteicos , Peptídeo Hidrolases/análise
6.
Proc Natl Acad Sci U S A ; 114(50): 13206-13211, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29180412

RESUMO

TGF-ß/BMP (bone morphogenetic protein) signaling pathways play conserved roles in controlling embryonic development, tissue homeostasis, and stem cell regulation. Inhibitory Smads (I-Smads) have been shown to negatively regulate TGF-ß/BMP signaling by primarily targeting the type I receptors for ubiquitination and turnover. However, little is known about how I-Smads access the membrane to execute their functions. Here we show that Dad, the Drosophila I-Smad, associates with the cellular membrane via palmitoylation, thereby targeting the BMP type I receptor for ubiquitination. By performing systematic biochemistry assays, we characterized the specific cysteine (Cys556) essential for Dad palmitoylation and membrane association. Moreover, we demonstrate that dHIP14, a Drosophila palmitoyl acyl-transferase, catalyzes Dad palmitoylation, thereby inhibiting efficient BMP signaling. Thus, our findings uncover a modification of the inhibitory Smads that controls TGF-ß/BMP signaling activity.


Assuntos
Membrana Celular/metabolismo , Proteínas de Drosophila/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Proteínas Smad/metabolismo , Aciltransferases/metabolismo , Animais , Sítios de Ligação , Proteínas Morfogenéticas Ósseas/metabolismo , Drosophila , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Lipoilação , Ligação Proteica , Transporte Proteico , Proteínas Smad/química , Proteínas Smad/genética , Fator de Crescimento Transformador beta/metabolismo
7.
Cancer Cell Int ; 19: 332, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827406

RESUMO

BACKGROUND: Abiraterone and MDV3100 are two effective anticancer agents for prostate cancer, however, the mechanism of their downstream action remains undefined. METHODS: A dual fluorescent biosensor plasmid was transfected in LNCaP cells to measure mitophagy. The DNA of LNCaP cells was extracted and performed with quantitative real-time PCR to detect mitochondrial DNA copy number. JC-1 staining was utilized to detect the mitochondrial membrane potential and electron microscope was performed to analyze mitochondrial morphology. Moreover, the protein levels of mitochondrial markers and apoptotic markers were detected by western blot. At last, the proliferation and apoptosis of LNCaP cells were analyzed with CCK-8 assay and flow cytometry after abiraterone or MDV3100 treatment. RESULTS: Mitophagy was induced by abiraterone and MDV3100 in LNCaP cells. The low expression level of mitochondrial DNA copy number and mitochondrial depolarization were further identified in the abiraterone or MDV3100 treatment groups compared with the control group. Besides, severe mitochondria swelling and substantial autophagy-lysosomes were observed in abiraterone- and MDV3100-treated LNCaP cells. The expression of mitochondria-related proteins, frataxin, ACO2 and Tom20 were significantly downregulated in abiraterone and MDV3100 treated LNCaP cells, whereas the expression level of inner membrane protein of mitochondria (Tim23) was significantly upregulated in the same condition. Moreover, the proliferation of LNCaP cells were drastically inhibited, and the apoptosis of LNCaP cells was increased in abiraterone or MDV3100 treatment groups. Meanwhile, the addition of mitophagy inhibitor Mdivi-1 (mitochondrial division inhibitor 1) could conversely elevate proliferation and constrain apoptosis of LNCaP cells. CONCLUSIONS: Our results prove that both abiraterone and MDV3100 inhibit the proliferation, promote the apoptosis of prostate cancer cells through regulating mitophagy. The promotion of mitophagy might enhance the efficacy of abiraterone and MDV3100, which could be a potential strategy to improve chemotherapy with these two reagents.

8.
Respir Res ; 19(1): 201, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30314482

RESUMO

BACKGROUND: The nitric oxide-soluble guanylate cyclase-cyclic guanosine monophosphate (NO-sGC-cGMP) signaling pathway, plays a critical role in the pathogenesis of pulmonary arterial hypertension (PAH); however, its exact molecular mechanism remains undefined. METHODS: Biotin-cGMP pull-down assay was performed to search for proteins regulated by cGMP. The interaction between cGMP and tropomyosin was analyzed with antibody dependent pull-down in vivo. Tropomyosin fragments were constructed to explore the tropomyosin-cGMP binding sites. The expression level and subcellular localization of tropomyosin were detected with Real-time PCR, Western blot and immunofluorescence assay after the 8-Br-cGMP treatment. Finally, isothermal titration calorimetry (ITC) was utilized to detect the binding affinity of actin-tropomyosin-myosin in the existence of cGMP-tropomyosin interaction. RESULTS: cGMP interacted with tropomyosin. Isoform 4 of TPM1 gene was identified as the only isoform expressed in the human pulmonary artery smooth muscle cells (HPASMCs). The region of 68-208aa of tropomyosin was necessary for the interaction between tropomyosin and cGMP. The expression level and subcellular localization of tropomyosin showed no change after the stimulation of NO-sGC-cGMP pathway. However, cGMP-tropomyosin interaction decreased the affinity of tropomyosin to actin. CONCLUSIONS: We elucidate the downstream signal pathway of NO-sGC-cGMP. This work will contribute to the detection of innovative targeted agents and provide novel insights into the development of new therapies for PAH.


Assuntos
Actinas/metabolismo , GMP Cíclico/metabolismo , Regulação para Baixo/fisiologia , Miosinas/metabolismo , Tropomiosina/metabolismo , Actinas/genética , Sequência de Aminoácidos , GMP Cíclico/genética , Humanos , Miócitos de Músculo Liso/metabolismo , Miosinas/genética , Ligação Proteica/fisiologia , Artéria Pulmonar/citologia , Artéria Pulmonar/metabolismo , Tropomiosina/genética
9.
Med Sci Monit ; 24: 3034-3041, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29741162

RESUMO

BACKGROUND The aim of this study was to evaluate the role of the urinary sarcosine/creatinine ratio in the diagnosis and prognosis of prostate cancer, using a sarcosine oxidase assay. MATERIAL AND METHODS Urine samples were obtained from 203 patients with benign prostate hyperplasia (BPH) and 209 patients with prostate cancer. Levels of urinary sarcosine were measured using the sarcosine oxidase method. The urinary sarcosine/creatinine ratios were compared between the group of patients with BPH and the patients with prostate cancer. In the two patients groups, the urinary sarcosine/creatinine ratio was compared with the measurement of serum prostate-specific antigen (PSA) and the free/total (F/T) PSA ratio. Correlations between of the urinary sarcosine/creatinine ratio and the Gleason grade and stage of prostate cancer were analyzed. RESULTS There was a significant difference between the urinary sarcosine/creatinine ratio in the BPH group and prostate cancer group (P<0.01), which was independent of serum PSA. The receiver-operating characteristic (ROC) curve, and area under the curve (AUC) for the urinary sarcosine/creatinine ratio was significantly higher compared with the serum PSA and the F/T PSA ratio. There was a significant difference in the urinary sarcosine/creatinine ratio in patients with prostate cancer with Gleason score ≤6, 7, and ≥8, and between patients with metastatic and non-metastatic prostate cancer. CONCLUSIONS The urinary sarcosine/creatinine ratio was a diagnostic indicator of prostate cancer, for patients with a serum PSA level <10 ng/ml, and correlated with the Gleason score and with the presence of metastases (stage) of prostate cancer.


Assuntos
Biomarcadores Tumorais/urina , Creatinina/urina , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/urina , Sarcosina/urina , Área Sob a Curva , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Prognóstico , Neoplasias da Próstata/patologia , Curva ROC
10.
Appl Microbiol Biotechnol ; 101(14): 5639-5644, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28432439

RESUMO

Creatine kinase isoform CK-MB has been widely applied as a biomarker of myocardial injury. While a variety of methods have been used to measure CK-MB activity or mass in clinical laboratories, a CK-MB standard is needed to eliminate between-method bias. Because the in vitro expression of human creatine kinase generates three isoenzymes, CK-MM, CK-MB, and CK-BB, it is important to establish an effective method to purify the isoform CK-MB from the mixture. In this study, we aimed at using tandem affinity purification (TAP) to purify recombinant CK-MB protein and evaluate its value in clinical laboratories. After the optimized sequence coding CK-M and CK-B were synthesized, they were combined with TAP tags (6His and SBP) and inserted into a pRSFDuet vector; then, the constructed 6His-CK-M-SBP-CK-B-pRSF plasmid was transformed into Escherichia coli BL21 (DE3) for expression. After TAP, we obtained purified CK-MB protein. We also did recovery testing using the engineered CK-MB and standard CK-MB (Randox) at different concentrations, and the results suggested that the engineered CK-MB could be used as the reference material. Moreover, the stability study of recombinant CK-MB showed high stability during long-term storage at -80 °C. In conclusion, the TAP-purified recombinant CK-MB protein may be a much better and cheaper standard or reference material for clinical laboratories.


Assuntos
Cromatografia de Afinidade/métodos , Creatina Quinase Forma MB/genética , Creatina Quinase Forma MB/metabolismo , Escherichia coli/genética , Cromatografia de Afinidade/economia , Ensaios Enzimáticos Clínicos , Creatina Quinase Forma MB/isolamento & purificação , Estabilidade Enzimática , Escherichia coli/enzimologia , Humanos , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Padrões de Referência
11.
Med Sci Monit ; 23: 2226-2231, 2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-28490726

RESUMO

BACKGROUND Chronic heart failure (CHF) is a leading cause of death worldwide. A long noncoding RNA (lncRNA) named urothelial carcinoma associated 1 (UCA1) is important in multiple diseases. However, the role of UCA1 in CHF is still unknown. Our study investigated whether UCA1 could be applied as an ideal marker to diagnose and evaluate prognosis in CHF. MATERIAL AND METHODS Total plasma RNA was extracted from 67 CHF patients and 67 controls. Quantitative real-time polymerase chain reaction was used to determine the plasma level of UCA1. Correlations between UCA1 and clinical parameters were analyzed by Pearson correlation. Receiver operating characteristic curves (ROC) were obtained to analyze the predictive power of UCA1 and BNP for CHF. Kaplan-Meier survival curves were used to evaluate prognosis of CHF within 1 year. RESULTS There was no significant difference in elementary data between CHF and controls. Plasma UCA1 was much higher in CHF patients compared with controls. Plasma UCA1 was positively and negatively correlated with brain natriuretic peptide (BNP) and left ventricle ejection fraction (LVEF), respectively. Plasma UCA1 diagnosed CHF with a diagnostic power of 0.89 and a sensitivity and specificity of 100% [95% CI (0.9464-1)] and 76.12% [95%CI (0.6414-0.8569)] (P<0.05), respectively. CHF patients with higher plasma UCA1 had a lower survival rate than those with a lower level, and survival rate predicted by UCA1 had a similar tendency with BNP. However, there was no significant difference between these 2 markers in predicting the prognosis of CHF (P>0.05). CONCLUSIONS Plasma UCA1 might be an excellent indicator to diagnose CHF and it might predict poor outcomes of CHF.


Assuntos
Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/genética , RNA Longo não Codificante/sangue , Idoso , Estudos de Casos e Controles , Doença Crônica , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Peptídeo Natriurético Encefálico/sangue , Prognóstico , RNA Longo não Codificante/genética , Curva ROC , Volume Sistólico , Taxa de Sobrevida
12.
Exp Cell Res ; 332(2): 278-87, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25704756

RESUMO

BACKGROUND: Different types of pulmonary hypertension (PH) share the same process of pulmonary vascular remodeling, the molecular mechanism of which is not entirely clarified by far. The abnormal biological behaviors of pulmonary arterial smooth muscle cells (PASMCs) play an important role in this process. OBJECTIVES: We investigated the regulation of plasminogen activator inhibitor-2 (PAI-2) by the sGC activator, and explored the effect of PAI-2 on PASMCs proliferation, apoptosis and migration. METHODS: After the transfection with PAI-2 overexpression vector and specific siRNAs or treatment with BAY 41-2272 (an activator of sGC), the mRNA and protein levels of PAI-2 in cultured human PASMCs were detected, and the proliferation, apoptosis and migration of PASMCs were investigated. RESULTS: BAY 41-2272 up regulated the endogenous PAI-2 in PASMCs, on the mRNA and protein level. In PAI-2 overexpression group, the proliferation and migration of PASMCs were inhibited significantly, and the apoptosis of PASMCs was increased. In contrast, PAI-2 knockdown with siRNA increased PASMCs proliferation and migration, inhibited the apoptosis. CONCLUSIONS: PAI-2 overexpression inhibits the proliferation and migration and promotes the apoptosis of human PASMCs. Therefore, sGC activator might alleviate or reverse vascular remodeling in PH through the up-regulation of PAI-2.


Assuntos
Anti-Hipertensivos/farmacologia , Apoptose/efeitos dos fármacos , Miócitos de Músculo Liso/fisiologia , Inibidor 2 de Ativador de Plasminogênio/metabolismo , Pirazóis/farmacologia , Piridinas/farmacologia , Benzoatos/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ativadores de Enzimas/farmacologia , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Inibidor 2 de Ativador de Plasminogênio/genética , Artéria Pulmonar/patologia , Regulação para Cima/efeitos dos fármacos
13.
ScientificWorldJournal ; 2014: 981724, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24688451

RESUMO

Dynamic scene stitching still has a great challenge in maintaining the global key information without missing or deforming if multiple motion interferences exist in the image acquisition system. Object clips, motion blurs, or other synthetic defects easily occur in the final stitching image. In our research work, we proceed from human visual cognitive mechanism and construct a hybrid-saliency-based cognitive model to automatically guide the video volume stitching. The model consists of three elements of different visual stimuli, that is, intensity, edge contour, and scene depth saliencies. Combined with the manifold-based mosaicing framework, dynamic scene stitching is formulated as a cut path optimization problem in a constructed space-time graph. The cutting energy function for column width selections is defined according to the proposed visual cognition model. The optimum cut path can minimize the cognitive saliency difference throughout the whole video volume. The experimental results show that it can effectively avoid synthetic defects caused by different motion interferences and summarize the key contents of the scene without loss. The proposed method gives full play to the role of human visual cognitive mechanism for the stitching. It is of high practical value to environmental surveillance and other applications.


Assuntos
Cognição , Simulação por Computador , Modelos Teóricos , Gravação em Vídeo , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Gravação em Vídeo/métodos
14.
Comput Struct Biotechnol J ; 23: 446-451, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38223342

RESUMO

The surge of genome sequencing data has underlined substantial genetic variants of uncertain significance (VUS). The decryption of VUS discovered by sequencing poses a major challenge in the post-sequencing era. Although experimental assays have progressed in classifying VUS, only a tiny fraction of the human genes have been explored experimentally. Thus, it is urgently needed to generate state-of-the-art functional predictors of VUS in silico. Artificial intelligence (AI) is an invaluable tool to assist in the identification of VUS with high efficiency and accuracy. An increasing number of studies indicate that AI has brought an exciting acceleration in the interpretation of VUS, and our group has already used AI to develop protein structure-based prediction models. In this review, we provide an overview of the previous research on AI-based prediction of missense variants, and elucidate the challenges and opportunities for protein structure-based variant prediction in the post-sequencing era.

15.
Clin Transl Med ; 13(9): e1393, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37649244

RESUMO

BACKGROUND: Small extrachromosomal circular DNAs (eccDNAs) have the potential to be cancer biomarkers. However, the formation mechanisms and functions of small eccDNAs selected in carcinogenesis are not clear, and whether the small eccDNA profile in the plasma of cancer patients represents that in cancer tissues remains to be elucidated. METHODS: A novel sequencing workflow based on the nanopore sequencing platform was used to sequence naturally existing full-length small eccDNAs in tissues and plasma collected from 25 cancer patients (including prostate cancer, hepatocellular carcinoma and colorectal cancer), and from an independent validation cohort (including 7 cancer plasma and 14 healthy plasma). RESULTS: Compared with those in non-cancer tissues, small eccDNAs detected in cancer tissues had a significantly larger number and size (P = 0.040 and 2.2e-16, respectively), along with more even distribution and different formation mechanisms. Although small eccDNAs had different general characteristics and genomic annotation between cancer tissues and the paired plasma, they had similar formation mechanisms and cancer-related functions. Small eccDNAs originated from some specific genes had great multi-cancer diagnostic value in tissues (AUC ≥ 0.8) and plasma (AUC > 0.9), especially increasing the accuracy of multi-cancer prediction of CEA/CA19-9 levels. The high multi-cancer diagnostic value of small eccDNAs originated from ALK&ETV6 could be extrapolated from tissues (AUC = 0.804) to plasma and showed high positive predictive value (100%) and negative predictive value (82.35%) in a validation cohort. CONCLUSIONS: As independent and stable circular DNA molecules, small eccDNAs in both tissues and plasma can be used as ideal biomarkers for cost-effective multi-cancer diagnosis and monitoring.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias da Próstata , Masculino , Humanos , Biomarcadores Tumorais/genética , DNA Circular/genética
16.
Cancer Innov ; 1(3): 197-206, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38089761

RESUMO

Circular RNAs (circRNAs) are a class of single-stranded closed RNAs that are produced by the back splicing of precursor mRNAs. The formation of circRNAs mainly involves intron-pairing-driven circularization, RNA-binding protein (RBP)-driven circularization, and lariat-driven circularization. The vast majority of circRNAs are found in the cytoplasm, and some intron-containing circRNAs are localized in the nucleus. CircRNAs have been found to function as microRNA (miRNA) sponges, interact with RBPs and translate proteins, and play an important regulatory role in the development and progression of cancer. CircRNAs exhibit tissue- and developmental stage-specific expression and are stable, with longer half-lives than linear RNAs. CircRNAs have great potential as biomarkers for cancer diagnosis and prognosis, which is highlighted by their detectability in tissues, especially in fluid biopsy samples such as plasma, saliva, and urine. Here, we review the current studies on the properties and functions of circRNAs and their clinical application value.

17.
Front Oncol ; 12: 842182, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35311085

RESUMO

Background: Bacillus Calmette-Guérin (BCG) is currently the most effective intravesical therapy for non-muscle-invasive bladder cancer (NMIBC) as it can prevent disease recurrence and progression and lower mortality. However, the response rates to BCG vary widely and are dependent on a multitude of factors. Methods: We performed a systematic discovery by analyzing the whole exome sequence, expression profile, and immune repertoire sequence of treatment-naive and 5-year time-serial relapsed tumors from 24 NMIBC patients. Results: BCG therapy showed bidirectional effects on tumor evolution and immune checkpoint landscape, along with a significant reduction of the percentage of neoantigen burden. In addition, a remarkable proportion of subclonal mutations were unique to the matched pre- or post-treatment tumors, suggesting the presence of BCG-induced and/or spatial heterogeneity. In the relapsed tumors, we identified and validated a shift in the mutational signatures in which mutations associated with aristolochic acid (AA) exposure were enriched, implying AA may be associated with tumor recurrence. Enhanced expressions of immune checkpoint regulation genes were found in the relapsed tumors, suggesting that the combination of immune checkpoint with BCG treatment may be an effective strategy to treat NMIBC. TCR sequencing revealed treatment-associated changes in the T-cell repertoire in the primary and relapsed tumors. Conclusion: Our results provide insight into the genomic and immune dynamics of tumor evolution with BCG treatment, suggest new mechanisms of BCG resistance, and inform the development of clinically relevant biomarkers and trials of potential immune checkpoint inhibitor combination therapies.

18.
Thorac Cancer ; 12(9): 1312-1319, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33704915

RESUMO

BACKGROUND: Thymomas and thymic carcinomas are the most common tumor types among anterior mediastinal lesions. However, the relationship between molecular aberrations and thymoma patients are poorly understood, especially abnormal changes in the expression profiles of circRNAs. The purpose of the present study was to investigate the expression profiles of circRNAs in thymoma patients and their possible roles in the pathogenesis of thymoma. METHODS: Diseased tissues and surrounding normal thymic tissues in two thymoma patients were collected for circRNA sequencing. The top four upregulated circRNAs were selected as candidates and further validated with RT-PCR in 20 thymoma patients. Gene ontology and signal transduction network analyses of circRNA-related mRNAs were performed to analyze the functional properties. Survival analysis of their parental genes were also carried out to evaluate the clinical value of differentially expressed circRNA. RESULTS: A total of 73 circRNAs were differentially expressed in thymoma tissues using high-throughput sequencing. Among these circRNAs, hsa_circ_0001173, hsa_circ_0007291, hsa_circ_0003550, and hsa_circ_0001947 were significantly upregulated in thymoma tissues compared with normal thymic tissues. We identified that these four circRNA-related mRNAs were involved in cell-cell adhesion, MAPK pathways, and TNF pathway, which may contribute to the pathological immune disorder in thymoma. Finally, we also found that SCAP (hsa_circ_0007291 parental gene) and AFF2 (hsa_circ_0001947 parental gene) were all significantly related with progression-free survival (PFS) of thymoma patients in a Kaplan-Meier plot (p-value <0.05). CONCLUSIONS: The expression levels of hsa_circ_0001173, hsa_circ_0007291, hsa_circ_0003550, and hsa_circ_0001947 were significantly upregulated and positively correlated with immune imbalance in thymoma patients.


Assuntos
RNA Circular/genética , Timoma/genética , Humanos , Análise de Sobrevida , Timoma/mortalidade
19.
Comb Chem High Throughput Screen ; 23(6): 546-553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32238134

RESUMO

OBJECTIVE: Next-generation sequencing (NGS) was performed to identify genes that were differentially expressed between normal thyroid tissue and papillary thyroid carcinoma (PTC). MATERIALS AND METHODS: Six candidate genes were selected and further confirmed with quantitative real-time polymerase chain reaction (qRT-PCR), and immunohistochemistry in samples from 24 fresh thyroid tumors and adjacent normal tissues. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was used to investigate signal transduction pathways of the differentially expressed genes. RESULTS: In total, 1690 genes were differentially expressed between samples from patients with PTC and the adjacent normal tissue. Among these, SFRP4, ZNF90, and DCN were the top three upregulated genes, whereas KIRREL3, TRIM36, and GABBR2 were downregulated with the smallest p values. Several pathways were associated with the differentially expressed genes and involved in cellular proliferation, cell migration, and endocrine system tumor progression, which may contribute to the pathogenesis of PTC. Upregulation of SFRP4, ZNF90, and DCN at the mRNA level was further validated with RT-PCR, and DCN expression was further confirmed with immunostaining of PTC samples. CONCLUSION: These results provide new insights into the molecular mechanisms of PTC. Identification of differentially expressed genes should not only improve the tumor signature for thyroid tumors as a diagnostic biomarker but also reveal potential targets for thyroid tumor treatment.


Assuntos
Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Proteínas de Transporte/genética , Decorina/genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de GABA-B/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-32296391

RESUMO

Although the rapid development of high-throughput sequencing has led to the identification of a large number of truncated or mutated steroid hormone receptor (SHR) variants, their clinical relevance remains to be defined. A platform for functional analysis of these SHR variants in cells would be instrumental for better assessing their impact on normal physiology and SHR-associated diseases. Here we have developed a new reporter system that allows rapid and accurate assessment of the transcriptional activity of SHR variants in cells. The reporter is a single construct containing a firefly luciferase reporter gene, whose expression is under the control of a promoter with multiple steroid hormone responsive elements, and a Renilla luciferase reporter gene, that is constitutively expressed under the control of an internal ribosome entry site (IRES) and is not regulated by steroid hormones. The corresponding SHR (wildtype or mutant/variant) is also expressed from the same construct. Using this improved reporter system, we revealed a large spectrum of transactivation activities within a set of previously identified mutations and variations of the androgen receptor (AR), the estrogen receptor α (ERα) and the glucocorticoid receptor (GR). This novel reporter system enables functional analysis of SHR mutants and variants in physiological and pathological settings, offering valuable preclinical, or diagnostic information for the understanding and treatment of associated diseases.


Assuntos
Bioensaio/métodos , Genes Reporter , Vetores Genéticos/genética , Regiões Promotoras Genéticas/genética , Receptores Citoplasmáticos e Nucleares/fisiologia , Ativação Transcricional/genética , Animais , Células COS , Células Cultivadas , Chlorocebus aethiops , Clonagem Molecular/métodos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Hormônios/farmacologia , Humanos , Luciferases de Vaga-Lume/genética , Proteínas Mutantes/fisiologia , Mutação , Regiões Promotoras Genéticas/efeitos dos fármacos , Receptores Androgênicos/genética , Receptores Androgênicos/fisiologia , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/fisiologia , Ativação Transcricional/efeitos dos fármacos , Transfecção/métodos
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