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2.
Am J Gastroenterol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38483300

RESUMO

INTRODUCTION: Complete viral suppression with nucleos(t)ide analogs (NAs) has led to a profound reduction in hepatocellular carcinoma and mortality among patients with chronic hepatitis B. Finite therapy yields higher rates of functional cure; however, initial hepatitis B virus (HBV) DNA and alanine aminotransferase (ALT) elevations are almost certain after treatment interruption. We aimed to analyze off-treatment outcomes beyond 12 months after NA cessation. METHODS: Patients with well-suppressed chronic hepatitis B who were hepatitis B e antigen-negative at NA cessation and remained off treatment without hepatitis B surface antigen (HBsAg) loss at 12 months were included (n = 945). HBV DNA and ALT fluctuations were allowed within the first 12 months. We used Kaplan-Meier methods to analyze outcomes beyond 12 months. Sustained remission was defined as HBV DNA <2,000 IU/mL and ALT <2× upper limit of normal (ULN) and an ALT flare as ALT ≥5× ULN. RESULTS: Cumulative probability of sustained remission was 29.7%, virological relapse was 65.2% with a mean peak HBV DNA of 5.0 ± 1.5 log 10 IU/mL, an ALT flare was 15.6% with a median peak ALT × ULN of 8.3 (5.7-11.3), HBsAg loss was 9.9% and retreatment was 34.9% at 48 months after NA cessation. A single occurrence of virological relapse or an ALT flare within the first 12 months off-treatment were associated with significantly lower rates of sustained remission beyond 12 months. DISCUSSION: Despite allowing for HBV DNA and ALT fluctuations within the first 12 months off-treatment, most patients without HBsAg loss did not maintain a sustained response thereafter. The best candidates for NA withdrawal are patients with low HBsAg levels at NA cessation, and those without profound or recurrent virological and biochemical relapses in the first off-treatment year.

3.
Liver Int ; 44(5): 1167-1175, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38353063

RESUMO

BACKGROUND & AIMS: FibroScan® Expert 630 and FibroScan® Mini+430 are novel vibration-controlled transient elastography devices equipped with the same SmartExam software, which allows continuous measurement of controlled attenuation parameter (CAP) during the entire examination. This study aims to compare the CAP variabilities and the quantification for liver fibrosis and steatosis between the conventional FibroScan and the SmartExam-equipped machines in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: This retrospective study included 118 patients with biopsy-proven MASLD who underwent liver biopsy at two tertiary centres between 2021 and 2023. Liver stiffness and steatosis measurements were performed using both FibroScan machines and M and XL probes for each individual. Liver histology was used as the reference standard for liver fibrosis and steatosis staging. RESULTS: Standard deviations of continuous CAP (cCAP) were significantly lower than those of CAP for all probes (p < .0001). CAP variability was significantly associated with body mass index (p < .01), probe selection (p < .001) as well as the random effect of centre. Only the effect of probe selection (p < .001) was significantly associated with cCAP variability. No significant difference was found in the performance of staging liver fibrosis and steatosis between two types of machines at the same cut-offs. CONCLUSIONS: The SmartExam-based VCTE reduces the variability of CAP measurement and achieves a similar accuracy as the FibroScan 502 device for the estimation of both hepatic steatosis and fibrosis. Future studies should determine if cCAP is a better tool to monitor changes in steatosis than the original CAP.


Assuntos
Técnicas de Imagem por Elasticidade , Doenças Metabólicas , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos Retrospectivos , Fígado/patologia , Cirrose Hepática/patologia
4.
Genome Res ; 34(2): 189-200, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38408788

RESUMO

Recent studies have revealed an unexplored population of long cell-free DNA (cfDNA) molecules in human plasma using long-read sequencing technologies. However, the biological properties of long cfDNA molecules (>500 bp) remain largely unknown. To this end, we have investigated the origins of long cfDNA molecules from different genomic elements. Analysis of plasma cfDNA using long-read sequencing reveals an uneven distribution of long molecules from across the genome. Long cfDNA molecules show overrepresentation in euchromatic regions of the genome, in sharp contrast to short DNA molecules. We observe a stronger relationship between the abundance of long molecules and mRNA gene expression levels, compared with short molecules (Pearson's r = 0.71 vs. -0.14). Moreover, long and short molecules show distinct fragmentation patterns surrounding CpG sites. Leveraging the cleavage preferences surrounding CpG sites, the combined cleavage ratios of long and short molecules can differentiate patients with hepatocellular carcinoma (HCC) from non-HCC subjects (AUC = 0.87). We also investigated knockout mice in which selected nuclease genes had been inactivated in comparison with wild-type mice. The proportion of long molecules originating from transcription start sites are lower in Dffb-deficient mice but higher in Dnase1l3-deficient mice compared with that of wild-type mice. This work thus provides new insights into the biological properties and potential clinical applications of long cfDNA molecules.


Assuntos
Carcinoma Hepatocelular , Ácidos Nucleicos Livres , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Ácidos Nucleicos Livres/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , DNA/genética , Genômica , Camundongos Knockout , Endodesoxirribonucleases/genética
5.
Liver Int ; 44(1): 15-26, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37650363

RESUMO

BACKGROUND & AIMS: The steatosis-associated fibrosis estimator (SAFE) score was developed to detect clinically significant liver fibrosis in patients with NAFLD in the United States. We compare the performance of the SAFE score and other non-invasive tests to diagnose liver fibrosis and to correlate the scores with liver-related outcomes in patients with NAFLD in Hong Kong. METHODS: This was a retrospective cohort study involving two data sets. The first cohort was a biopsy cohort of NAFLD patients (n = 279), and the second was a territory-wide cohort of NAFLD patients (n = 4603) retrieved from a territory-wide electronic healthcare database in Hong Kong. RESULTS: In detecting significant fibrosis, liver stiffness measured by transient elastography had the highest area under the receiver operating characteristic curve (AUROC) (.844), followed by SAFE score (.773). SAFE score had the highest AUROC among blood-based algorithms (.773 vs. .746 for FIB-4, .697 for APRI). Based on cut-off values of SAFE score (0 and 100 points), 854 (18.6%), 1596 (34.6%) and 2153 (46.8%) were in the low-, intermediate- and high-risk groups, respectively, in the territory-wide cohort. Six (.7%), 15 (.9%) and 59 (2.7%) developed liver-related events in those three groups respectively. Among patients who had liver-related events at 5 years, using the high cut-off, SAFE score could predict 84.9% of patients accurately, compared to 40.9% for FIB-4 and 27.2% for APRI. CONCLUSION: The SAFE score performed well and better than other blood-based markers in diagnosing significant fibrosis and predicting liver-related events in Asian patients with NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Prognóstico , Estudos Retrospectivos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Fibrose , Biópsia
6.
Proc Natl Acad Sci U S A ; 120(17): e2220982120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37075072

RESUMO

Cell-free DNA (cfDNA) fragmentation is nonrandom, at least partially mediated by various DNA nucleases, forming characteristic cfDNA end motifs. However, there is a paucity of tools for deciphering the relative contributions of cfDNA cleavage patterns related to underlying fragmentation factors. In this study, through non-negative matrix factorization algorithm, we used 256 5' 4-mer end motifs to identify distinct types of cfDNA cleavage patterns, referred to as "founder" end-motif profiles (F-profiles). F-profiles were associated with different DNA nucleases based on whether such patterns were disrupted in nuclease-knockout mouse models. Contributions of individual F-profiles in a cfDNA sample could be determined by deconvolutional analysis. We analyzed 93 murine cfDNA samples of different nuclease-deficient mice and identified six types of F-profiles. F-profiles I, II, and III were linked to deoxyribonuclease 1 like 3 (DNASE1L3), deoxyribonuclease 1 (DNASE1), and DNA fragmentation factor subunit beta (DFFB), respectively. We revealed that 42.9% of plasma cfDNA molecules were attributed to DNASE1L3-mediated fragmentation, whereas 43.4% of urinary cfDNA molecules involved DNASE1-mediated fragmentation. We further demonstrated that the relative contributions of F-profiles were useful to inform pathological states, such as autoimmune disorders and cancer. Among the six F-profiles, the use of F-profile I could inform the human patients with systemic lupus erythematosus. F-profile VI could be used to detect individuals with hepatocellular carcinoma, with an area under the receiver operating characteristic curve of 0.97. F-profile VI was more prominent in patients with nasopharyngeal carcinoma undergoing chemoradiotherapy. We proposed that this profile might be related to oxidative stress.


Assuntos
Ácidos Nucleicos Livres , Humanos , Camundongos , Animais , Ácidos Nucleicos Livres/genética , Desoxirribonucleases/genética , Camundongos Knockout , Endonucleases/genética , Fragmentação do DNA , Endodesoxirribonucleases/genética
7.
Liver Int ; 43(5): 1008-1014, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36855842

RESUMO

BACKGROUND: Chronic hepatitis B (CHB) is endemic to Asia and is a leading cause of liver-related morbidity. The prevalence of concomitant CHB and hepatic steatosis (HS) is increasing in Asia. Non-invasive tests (NITs) including FIB-4, NFS and APRI assess fibrosis in populations with a single aetiology, but not in subjects with concomitant CHB and HS. AIM: To explore the accuracy of NITs in predicting advanced fibrosis in patients with concomitant CHB and HS. METHODOLOGY: This multicentre study of CHB patients who underwent liver biopsy explored clinical characteristics of these subjects, stratified by presence of HS. Fibrosis scores from NITs were compared against histological fibrosis stage in CHB subjects with and without HS. RESULTS: 2262 subjects were enrolled, 74.5% were males, and the mean age was 39.5 years ±11.8 SD. 984 (44.4%) had HS, 824 (36.4%) had advanced fibrosis. In the CHB group, the AUROC for advanced fibrosis were 0.65 (95% CI 0.62-0.69) for FIB-4 and 0.63 (95% CI 0.60-0.66) for APRI. The specificities were 0.94 for FIB-4 greater than 3.25 and 0.81 for APRI greater than 1.5. In the CHBHS group, the AUROC for advanced fibrosis were 0.67 (95% CI 0.63-0.71) for FIB-4, 0.60 (95% CI 0.56-0.64) for APRI and 0.65 (95% CI 0.61-0.69) for NFS. The specificities were 0.95 for FIB-4 greater than 3.25, 0.88 for APRI greater than 1.5 and 0.99 for NFS greater than 0.675. CONCLUSION: The performance of NITs to exclude advanced fibrosis did not differ greatly regardless of HS. FIB-4 and NFS have the best negative predictive values of 0.80 and 0.78, respectively, to exclude advanced fibrosis in CHBHS subjects.


Assuntos
Fígado Gorduroso , Hepatite B Crônica , Masculino , Humanos , Adulto , Feminino , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Cirrose Hepática/complicações , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/patologia , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/complicações , Valor Preditivo dos Testes , Biópsia , Aspartato Aminotransferases , Índice de Gravidade de Doença , Biomarcadores , Curva ROC
8.
Liver Int ; 43(3): 588-598, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36516362

RESUMO

BACKGROUND: It is uncertain whether biological therapies would increase the risk of hepatitis among patients with past hepatitis B virus (HBV) infection. This study aimed to evaluate the risk of alanine aminotransferase (ALT) flare in patients with past HBV infection while using biological therapies. METHODOLOGY: Patients who received biological therapies for ≥3 months from 2000 to 2019 were identified from a population-based database in Hong Kong. Patients with past HBV infection were compared with a control group without prior HBV exposure. The primary endpoint was development of ALT flare within 5 years of starting biological therapies, defined as ALT >80 IU/L. RESULTS: There were 2471 and 2394 patients with and without past HBV infection respectively. There was a non-significant increase in risk of ALT flare among the HBV-exposed group (27.6% vs. 23.7%, p = .055). In multivariable analysis, using prednisolone-equivalent dose of >20 mg daily, male sex and concomitant immunosuppressants were risk factors for ALT flare. The risk of ALT flare was significantly higher with anti-CD20 when compared to other biological agents (36.1% vs. 14.5%, p < .01), but was not significantly different among anti-tumour necrosis factor, anti-cytokine, Janus kinase inhibitors and T cell/B cell inhibitors or anti-integrin (15.2% vs. 14.6% vs. 11.7% vs. 11.1%, p = .82). Among patients with documented hepatitis B surface antigen seroreversion, 96% were on anti-CD20. CONCLUSIONS: Our study further supports the current suggestion of prophylactic anti-viral before starting anti-CD20 in HBV-exposed patients. While other biological therapies appear to have a lower risk for ALT flare, this result needs further confirmation.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Masculino , Vírus da Hepatite B/genética , Alanina Transaminase , Hepatite B Crônica/tratamento farmacológico , Hepatite B/complicações , Antivirais/uso terapêutico , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Terapia Biológica , DNA Viral
9.
Clin Chem ; 69(2): 168-179, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36322427

RESUMO

BACKGROUND: Recent studies using single molecule, real-time (SMRT) sequencing revealed a substantial population of analyzable long cell-free DNA (cfDNA) in plasma. Potential clinical utilities of such long cfDNA in pregnancy and cancer have been demonstrated. However, the performance of different long-read sequencing platforms for the analysis of long cfDNA remains unknown. METHODS: Size biases of SMRT sequencing by Pacific Biosciences (PacBio) and nanopore sequencing by Oxford Nanopore Technologies (ONT) were evaluated using artificial mixtures of sonicated human and mouse DNA of different sizes. cfDNA from plasma samples of pregnant women at different trimesters, hepatitis B carriers, and patients with hepatocellular carcinoma were sequenced with the 2 platforms. RESULTS: Both platforms showed biases to sequence longer (1500 bp vs 200 bp) DNA fragments, with PacBio showing a stronger bias (5-fold overrepresentation of long fragments vs 2-fold in ONT). Percentages of cfDNA fragments 500 bp were around 6-fold higher in PacBio compared with ONT. End motif profiles of cfDNA from PacBio and ONT were similar, yet exhibited platform-dependent patterns. Tissue-of-origin analysis based on single-molecule methylation patterns showed comparable performance on both platforms. CONCLUSIONS: SMRT sequencing generated data with higher percentages of long cfDNA compared with nanopore sequencing. Yet, a higher number of long cfDNA fragments eligible for the tissue-of-origin analysis could be obtained from nanopore sequencing due to its much higher throughput. When analyzing the size and end motif of cfDNA, one should be aware of the analytical characteristics and possible biases of the sequencing platforms being used.


Assuntos
Ácidos Nucleicos Livres , Neoplasias Hepáticas , Sequenciamento por Nanoporos , Humanos , Feminino , Gravidez , Animais , Camundongos , Ácidos Nucleicos Livres/genética , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , DNA/genética
10.
Proc Natl Acad Sci U S A ; 119(44): e2209852119, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36288287

RESUMO

Cell-free DNA (cfDNA) fragmentation patterns contain important molecular information linked to tissues of origin. We explored the possibility of using fragmentation patterns to predict cytosine-phosphate-guanine (CpG) methylation of cfDNA, obviating the use of bisulfite treatment and associated risks of DNA degradation. This study investigated the cfDNA cleavage profile surrounding a CpG (i.e., within an 11-nucleotide [nt] window) to analyze cfDNA methylation. The cfDNA cleavage proportion across positions within the window appeared nonrandom and exhibited correlation with methylation status. The mean cleavage proportion was ∼twofold higher at the cytosine of methylated CpGs than unmethylated ones in healthy controls. In contrast, the mean cleavage proportion rapidly decreased at the 1-nt position immediately preceding methylated CpGs. Such differential cleavages resulted in a characteristic change in relative presentations of CGN and NCG motifs at 5' ends, where N represented any nucleotide. CGN/NCG motif ratios were correlated with methylation levels at tissue-specific methylated CpGs (e.g., placenta or liver) (Pearson's absolute r > 0.86). cfDNA cleavage profiles were thus informative for cfDNA methylation and tissue-of-origin analyses. Using CG-containing end motifs, we achieved an area under a receiver operating characteristic curve (AUC) of 0.98 in differentiating patients with and without hepatocellular carcinoma and enhanced the positive predictive value of nasopharyngeal carcinoma screening (from 19.6 to 26.8%). Furthermore, we elucidated the feasibility of using cfDNA cleavage patterns to deduce CpG methylation at single CpG resolution using a deep learning algorithm and achieved an AUC of 0.93. FRAGmentomics-based Methylation Analysis (FRAGMA) presents many possibilities for noninvasive prenatal, cancer, and organ transplantation assessment.


Assuntos
Ácidos Nucleicos Livres , Neoplasias Hepáticas , Gravidez , Feminino , Humanos , Ácidos Nucleicos Livres/genética , Biomarcadores Tumorais/genética , Metilação de DNA , Neoplasias Hepáticas/genética , Epigênese Genética , DNA/genética , Citosina , Guanina , Nucleotídeos , Fosfatos
11.
Semin Cancer Biol ; 86(Pt 3): 84-106, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35995341

RESUMO

Breast cancer is the most commonly diagnosed cancer and second-leading cause of cancer deaths in women. Breast cancer stem cells (BCSCs) promote metastasis and therapeutic resistance contributing to tumor relapse. Through activating genes important for BCSCs, transcription factors contribute to breast cancer metastasis and therapeutic resistance, including the signal transducer and activator of transcription (STAT) family of transcription factors. The STAT family consists of six major isoforms, STAT1, STAT2, STAT3, STAT4, STAT5, and STAT6. Canonical STAT signaling is activated by the binding of an extracellular ligand to a cell-surface receptor followed by STAT phosphorylation, leading to STAT nuclear translocation and transactivation of target genes. It is important to note that STAT transcription factors exhibit diverse effects in breast cancer; some are either pro- or anti-tumorigenic while others maintain dual, context-dependent roles. Among the STAT transcription factors, STAT3 is the most widely studied STAT protein in breast cancer for its critical roles in promoting BCSCs, breast cancer cell proliferation, invasion, angiogenesis, metastasis, and immune evasion. Consequently, there have been substantial efforts in developing cancer therapeutics to target breast cancer with dysregulated STAT3 signaling. In this comprehensive review, we will summarize the diverse roles that each STAT family member plays in breast cancer pathobiology, as well as, the opportunities and challenges in pharmacologically targeting STAT proteins and their upstream activators in the context of breast cancer treatment.


Assuntos
Neoplasias da Mama , Segunda Neoplasia Primária , Feminino , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas , Carcinogênese
12.
Cancer Lett ; 540: 215726, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35589002

RESUMO

Mechanisms underlying breast cancer brain metastasis (BCBM) are still unclear. In this study, we observed that extracellular vesicles (EVs) secreted from breast cancer cells with increased expression of tGLI1, a BCBM-promoting transcription factor, strongly activated astrocytes. EV-derived microRNA/miRNA microarray revealed tGLI1-positive breast cancer cells highly secreted miR-1290 and miR-1246 encapsulated in EVs. Genetic knockin/knockout studies established a direct link between tGLI1 and both miRNAs. Datamining and analysis of patient samples revealed that BCBM patients had more circulating EV-miRs-1290/1246 than those without metastasis. Ectopic expression of miR-1290 or miR-1246 strongly activated astrocytes whereas their inhibitors abrogated the effect. Conditioned media from miR-1290- or miR-1246-overexpressing astrocytes promoted mammospheres. Furthermore, miRs-1290/1246 suppressed expression of FOXA2 transcription repressor, leading to CNTF cytokine secretion and subsequent activation of astrocytes. Finally, we conducted a mouse study to demonstrate that astrocytes overexpressing miR-1290, but not miR-1246, enhanced intracranial colonization and growth of breast cancer cells. Collectively, our findings demonstrate, for the first time, that breast cancer EV-derived miR-1290 and miR-1246 activate astrocytes in the brain metastatic microenvironment and that EV-derived miR-1290 promotes progression of brain metastases through the novel EV-miR-1290→FOXA2→CNTF signaling axis.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Fator Neurotrófico Ciliar , Vesículas Extracelulares , Fator 3-beta Nuclear de Hepatócito , MicroRNAs , Animais , Astrócitos/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Fator Neurotrófico Ciliar/metabolismo , Vesículas Extracelulares/metabolismo , Feminino , Fator 3-beta Nuclear de Hepatócito/genética , Fator 3-beta Nuclear de Hepatócito/metabolismo , Humanos , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Microambiente Tumoral
13.
Clin Chem ; 68(9): 1151-1163, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35587130

RESUMO

BACKGROUND: Analysis of circulating tumor DNA has become increasingly important as a tool for cancer care. However, the focus of previous studies has been on short fragments of DNA. Also, bisulfite sequencing, a conventional approach for methylation analysis, causes DNA degradation, which is not ideal for the assessment of long DNA properties and methylation patterns. This study attempted to overcome such obstacles by single-molecule sequencing. METHODS: Single-molecule real-time (SMRT) sequencing was used to sequence plasma DNA. We performed fragment size and direct methylation analysis for each molecule. A methylation score concerning single-molecule methylation patterns was used for cancer detection. RESULTS: A substantial proportion of plasma DNA was longer than 1 kb with a median of 16% in hepatocellular carcinoma (HCC) patients, hepatitis B virus carriers, and healthy individuals. The longest plasma DNA molecule in the HCC patients was 39.8 kb. Tumoral cell-free DNA (cfDNA) was generally shorter than nontumoral cfDNA. The longest tumoral cfDNA was 13.6 kb. Tumoral cfDNA had lower methylation levels compared with nontumoral cfDNA (median: 59.3% vs 76.9%). We developed and analyzed a metric reflecting single-molecule methylation patterns associated with cancer, named the HCC methylation score. HCC patients displayed significantly higher HCC methylation scores than those without HCC. Interestingly, compared to using short cfDNA (area under the receiver operating characteristic [ROC] curve, AUC: 0.75), the use of long cfDNA molecules greatly enhanced the discriminatory power (AUC: 0.91). CONCLUSIONS: A previously unidentified long cfDNA population was revealed in cancer patients. The presence and direct methylation analysis of these molecules open new possibilities for cancer liquid biopsy.


Assuntos
Carcinoma Hepatocelular , Ácidos Nucleicos Livres , Neoplasias Hepáticas , Biomarcadores Tumorais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Ácidos Nucleicos Livres/genética , DNA , Metilação de DNA , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética
14.
Front Oncol ; 12: 866014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371975

RESUMO

Breast cancer is the most commonly diagnosed cancer in women. Metastasis is the primary cause of mortality for breast cancer patients. Multiple mechanisms underlie breast cancer metastatic dissemination, including the interleukin-6 (IL-6)-mediated signaling pathway. IL-6 is a pleiotropic cytokine that plays an important role in multiple physiological processes including cell proliferation, immune surveillance, acute inflammation, metabolism, and bone remodeling. IL-6 binds to the IL-6 receptor (IL-6Rα) which subsequently binds to the glycoprotein 130 (gp130) receptor creating a signal transducing hexameric receptor complex. Janus kinases (JAKs) are recruited and activated; activated JAKs, in turn, phosphorylate signal transducer and activator of transcription 3 (STAT3) for activation, leading to gene regulation. Constitutively active IL-6/JAK/STAT3 signaling drives cancer cell proliferation and invasiveness while suppressing apoptosis, and STAT3 enhances IL-6 signaling to promote a vicious inflammatory loop. Aberrant expression of IL-6 occurs in multiple cancer types and is associated with poor clinical prognosis and metastasis. In breast cancer, the IL-6 pathway is frequently activated, which can promote breast cancer metastasis while simultaneously suppressing the anti-tumor immune response. Given these important roles in human cancers, multiple components of the IL-6 pathway are promising targets for cancer therapeutics and are currently being evaluated preclinically and clinically for breast cancer. This review covers the current biological understanding of the IL-6 signaling pathway and its impact on breast cancer metastasis, as well as, therapeutic interventions that target components of the IL-6 pathway including: IL-6, IL-6Rα, gp130 receptor, JAKs, and STAT3.

15.
Gastrointest Endosc ; 96(3): 530-542.e1, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35413329

RESUMO

BACKGROUND AND AIMS: Evidence of prophylactic clipping is inconsistent except for proximal and large colonic lesions in the general population. Although warfarin and direct oral anticoagulants (DOACs) are significant risk factors of postpolypectomy bleeding (PPB), dedicated studies to examine the benefit of prophylactic clipping in these high-risk patients remain limited. METHODS: We performed a propensity score-weighted retrospective cohort study from 2012 to 2020. Patients who received an oral anticoagulant and underwent colonoscopic polypectomy were included. Data were collected on baseline demographics, medications (anticoagulant, antiplatelet, and heparin bridging), and endoscopies (polyp number, location, size, morphology, histopathology, resection method and prophylactic clipping). Propensity-score models with inverse probability of treatment weighting were developed between prophylactic clipping and no clipping groups. Unbalanced variables were included in a doubly robust model with multivariate analysis. The primary outcome was clinically significant delayed PPB, defined as a composite endpoint of hemoglobin drop ≥2 g/dL, blood transfusion, or repeat colonoscopy for hemostasis within 30 days. RESULTS: Five hundred forty-seven patients with 1485 polyps were included. Prophylactic clipping was not associated with a reduced risk of PPB (odds ratio [OR], 1.19; 95% confidence interval [CI], .73-1.95; P = .497). The hot resection method was associated with a significantly higher risk of PPB (OR, 9.76; 95% CI, 3.94-32.60; P < .001) compared with cold biopsy or snare polypectomy. In a subgroup analysis, prophylactic clipping was associated with a lower PPB risk in patients on DOACs (OR, .36; 95% CI, .16-.82; P = .015). CONCLUSIONS: Prophylactic clipping was not associated with an overall reduced risk of PPB in patients on oral anticoagulants. The use of cold snare polypectomy should be maximized in anticoagulated patients.


Assuntos
Pólipos do Colo , Anticoagulantes , Pólipos do Colo/patologia , Colonoscopia/métodos , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/prevenção & controle , Pontuação de Propensão , Estudos Retrospectivos
16.
Cancer Lett ; 531: 124-135, 2022 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-35167936

RESUMO

Whether tumor suppressor candidate 2 (TUSC2) plays an important role in glioblastoma (GBM) progression is largely unknown. Whether TUSC2 undergoes polyubiquitination is unknown. Herein, we report that TUSC2 protein expression is reduced/lost in GBM compared to normal brain due to protein destabilization; TUSC2 mRNA is equally expressed in both tissues. NEDD4 E3 ubiquitin ligase polyubiquitinates TUSC2 at residue K71, and the TUSC2-K71R mutant is resistant to NEDD4-mediated proteasomal degradation. Analysis of GBM specimens showed NEDD4 protein is highly expressed in GBM and the level is inversely correlated with TUSC2 protein levels. Furthermore, TUSC2 restoration induces apoptosis and inhibits patient-derived glioma stem cells (PD-GSCs) in vitro and in vivo. Conversely, TUSC2-knockout promotes PD-GSCs in vitro and in vivo. RNA-Seq analysis and subsequent validations showed GBM cells with TUSC2-knockout expressed increased Bcl-xL and were more resistant to apoptosis induced by a Bcl-xL-specific BH3 mimetic. A TUSC2-knockout gene signature created from the RNA-seq data predicts poor patient survival. Together, these findings establish that NEDD4-mediated polyubiquitination is a novel mechanism for TUSC2 degradation in GBM and that TUSC2 loss promotes GBM progression in part through Bcl-xL upregulation.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Genes Supressores de Tumor , Glioblastoma/patologia , Glioma/genética , Humanos , Proteínas Supressoras de Tumor/genética , Ubiquitinação
17.
Gut ; 71(8): 1544-1550, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34548338

RESUMO

OBJECTIVE: While it is recommended that patients presenting with acute upper gastrointestinal bleeding (AUGIB) should receive endoscopic intervention within 24 hours, the optimal timing is still uncertain. We aimed to assess whether endoscopy timing postadmission would affect outcomes. DESIGN: We conducted a retrospective, territory-wide, cohort study with healthcare data from all public hospitals in Hong Kong. Adult patients (age ≥18) that presented with AUGIB between 2013 and 2019 and received therapeutic endoscopy within 48 hours (n=6474) were recruited. Patients were classified based on endoscopic timing postadmission: urgent (t≤6), early (6

Assuntos
Endoscopia Gastrointestinal , Hemorragia Gastrointestinal , Doença Aguda , Adulto , Estudos de Coortes , Endoscopia Gastrointestinal/métodos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Humanos , Estudos Retrospectivos
18.
Clin Gastroenterol Hepatol ; 20(4): 874-885.e4, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34089852

RESUMO

BACKGROUND & AIMS: Antiviral treatment criteria are based on disease progression risk, and hepatocellular carcinoma (HCC) surveillance recommendations for patients with chronic hepatitis B (CHB) without cirrhosis is based on an annual incidence threshold of 0.2%. However, accurate and precise disease progression estimate data are limited. Thus, we aimed to determine rates of cirrhosis and HCC development stratified by age, sex, treatment status, and disease activity based on the 2018 American Association for the Study of Liver Diseases and 2017 European Association for the Study of the Liver guidelines. METHODS: We analyzed 18,338 patients (8914 treated, 9424 untreated) from 6 centers from the United States and 27 centers from Asia-Pacific countries. The Kaplan-Meier method was used to estimate annual progression rates to cirrhosis or HCC in person-years. RESULTS: The cohort was 63% male, with a mean age of 46.19 years, with baseline cirrhosis of 14.3% and median follow up of 9.60 years. By American Association for the Study of Liver Diseases criteria, depending on age, sex, and disease activity, annual incidence rates ranged from 0.07% to 3.94% for cirrhosis, from 0.04% to 2.19% for HCC in patients without cirrhosis, and from 0.40% to 8.83% for HCC in patients with cirrhosis. Several subgroups of patients without cirrhosis including males younger than 40 years of age and females younger than 50 years of age had annual HCC risk near or exceeding 0.2%. Similar results were found using European Association for the Study of the Liver criteria. CONCLUSION: There is great variability in CHB disease progression rates even among "lower-risk" populations. Future CHB modeling studies, public health planning, and HCC surveillance recommendation should be based on more precise disease progression rates based on sex, age, and disease activity, plus treatment status.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Antivirais/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/terapia , Feminino , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Humanos , Incidência , Cirrose Hepática/complicações , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Medicina de Precisão , Estudos Retrospectivos
19.
Cancers (Basel) ; 13(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066153

RESUMO

JAK2-STAT3 and TrkA signaling pathways have been separately implicated in aggressive breast cancers; however, whether they are co-activated or undergo functional interaction has not been thoroughly investigated. Herein we report, for the first time that STAT3 and TrkA are significantly co-overexpressed and co-activated in triple-negative breast cancer (TNBC) and HER2-enriched breast cancer, as shown by immunohistochemical staining and data mining. Through immunofluorescence staining-confocal microscopy and immunoprecipitation-Western blotting, we found that TrkA and STAT3 co-localize and physically interact in the cytoplasm, and the interaction is dependent on STAT3-Y705 phosphorylation. TrkA-STAT3 interaction leads to STAT3 phosphorylation at Y705 by TrkA in breast cancer cells and cell-free kinase assays, indicating that STAT3 is a novel substrate of TrkA. ß-NGF-mediated TrkA activation induces TrkA-STAT3 interaction, STAT3 nuclear transport and transcriptional activity, and the expression of STAT3 target genes, SOX2 and MYC. The co-activation of both pathways promotes breast cancer stem cells. Finally, we found that TNBC and HER2-enriched breast cancer with JAK2-STAT3 and TrkA co-activation are positively associated with poor overall metastasis-free and organ-specific metastasis-free survival. Collectively, our study uncovered that TrkA is a novel activating kinase of STAT3, and their co-activation enhances gene transcription and promotes breast cancer stem cells in TNBC and HER2-enriched breast cancer.

20.
Cancer Lett ; 516: 73-83, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34090924

RESUMO

Transgenic breast cancer mouse models are critical tools for preclinical studies of human breast cancer. Genetic editing of the murine mammary gland allows for modeling of abnormal genetic events frequently found in human breast cancers. Genetically engineered mouse models (GEMMs) of breast cancer employ tissue-specific genetic manipulation for tumorigenic induction within the mammary tissue. Under the transcriptional control of mammary-specific promoters, transgenic mouse models can simulate spontaneous mammary tumorigenesis by expressing one or more putative oncogenes, such as MYC, HRAS, and PIK3CA. Alternatively, the Cre-Lox system allows for tissue-specific deletion of tumor suppressors, such as p53, Rb1, and Brca1, or specific knock-in of putative oncogenes. Thus, GEMMs can be designed to implement one or more genetic events to induce mammary tumorigenesis. Features of GEMMs, such as age of transgene expression, breeding quality, tumor latency, histopathological characteristics, and propensity for local and distant metastasis, are variable and strain-dependent. This review aims to summarize currently available transgenic breast cancer mouse models that undergo spontaneous mammary tumorigenesis upon genetic manipulation, their varying characteristics, and their individual genetic manipulations that model aberrant signaling events observed in human breast cancers.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos Transgênicos/genética , Animais , Carcinogênese/genética , Carcinogênese/patologia , Modelos Animais de Doenças , Feminino , Humanos , Glândulas Mamárias Animais/patologia
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