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1.
Can Vet J ; 65(5): 514-519, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38694745
2.
Vet Dermatol ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38818665

RESUMEN

Feline proliferative and necrotising otitis externa (PNOE) is a rare immune-mediated condition, usually self-limiting or responsive to immunosuppressants such as topical tacrolimus. This case report describes two cats with refractory PNOE that responded successfully to oclacitinib. One cat also had middle ear involvement and the other cat had extra-auricular dermatitis.

3.
Front Oncol ; 14: 1345322, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38357197

RESUMEN

Background: Androgen deprivation therapy (ADT) is the foundational treatment for metastatic prostate cancer (PCa). Androgen receptor (AR) axis-targeted therapies are a new standard of care for advanced PCa. Although these agents have significantly improved patient survival, the suppression of testosterone is associated with an increased risk of cardiometabolic syndrome. This highlights the urgency of multidisciplinary efforts to address the cardiometabolic risk of anticancer treatment in men with PCa. Methods: Two professional organizations invited five urologists, five clinical oncologists, and two cardiologists to form a consensus panel. They reviewed the relevant literature obtained by searching PubMed for the publication period from April 2013 to April 2023, to address three discussion areas: (i) baseline assessment and screening for risk factors in PCa patients before the initiation of ADT and AR axis-targeted therapies; (ii) follow-up and management of cardiometabolic complications; and (iii) selection of ADT agents among high-risk patients. The panel convened four meetings to discuss and draft consensus statements using a modified Delphi method. Each drafted statement was anonymously voted on by every panelist. Results: The panel reached a consensus on 18 statements based on recent evidence and expert insights. Conclusion: These consensus statements serve as a practical recommendation for clinicians in Hong Kong, and possibly the Asia-Pacific region, in the management of cardiometabolic toxicities of ADT or AR axis-targeted therapies in men with PCa.

4.
Clin Genitourin Cancer ; 22(1): e75-e85.e1, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37604745

RESUMEN

INTRODUCTION: Abiraterone acetate (ABI) or docetaxel (DOC), in addition to androgen-deprivation therapy (ADT), are current treatment options for metastatic hormone-sensitive prostate cancer (mHSPC). No randomized head-to-head trial has compared these 2 mHSPC treatments, and real-world data regarding their outcomes in Asian patients are lacking. PATIENTS AND METHODS: The medical records of mHSPC patients who began upfront ABI or DOC treatment in addition to ADT at seven public oncology centers in Hong Kong between 2015 and 2021 were reviewed. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), prostate-specific antigen (PSA) response, and toxicities. Kaplan-Meier and multivariate Cox regression analyses were performed. RESULTS: A total of 574 patients were included, of whom 419 received DOC and 155 received ABI. The median follow-up duration was 22.4 (DOC group: 23.8; ABI group: 17.3) months. The ABI group demonstrated significantly better PFS than the DOC group (not reached vs. 15.1 months: hazard ratio = 0.37; 95% confidence interval = 0.28-0.50; P < .001). No significant OS difference was observed (P = .58). Failure to achieve a ≥ 90% decline in PSA level at 3 months and failure to achieve an undetectable PSA nadir were each associated with unfavorable PFS and OS. Patients who received DOC had a higher rate of febrile neutropenia, whereas those who received ABI had higher rates of grade ≥ 3 hypokalemia and elevated alanine transaminase. Treatment discontinuation due to toxicities was more common in the DOC (3.6%) than the ABI (0.6%) group. CONCLUSION: In Asian mHSPC patients, upfront ABI + ADT was associated with better PFS than DOC + ADT, with no significant OS difference. PSA kinetics may help stratify the prognosis for treatment intensification. Toxicity profiles were different, with a higher rate of toxicity-related treatment discontinuation in the DOC group.


Asunto(s)
Acetato de Abiraterona , Neoplasias de la Próstata , Masculino , Humanos , Docetaxel/uso terapéutico , Acetato de Abiraterona/efectos adversos , Neoplasias de la Próstata/patología , Antagonistas de Andrógenos/efectos adversos , Antígeno Prostático Específico , Hormonas , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Resultado del Tratamiento , Estudios Retrospectivos
5.
Bioengineering (Basel) ; 10(5)2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37237590

RESUMEN

Unbiased metagenomic sequencing is conceptually well-suited for first-line diagnosis as all known and unknown infectious entities can be detected, but costs, turnaround time and human background reads in complex biofluids, such as plasma, hinder widespread deployment. Separate preparations of DNA and RNA also increases costs. In this study, we developed a rapid unbiased metagenomics next-generation sequencing (mNGS) workflow with a human background depletion method (HostEL) and a combined DNA/RNA library preparation kit (AmpRE) to address this issue. We enriched and detected bacterial and fungal standards spiked in plasma at physiological levels with low-depth sequencing (<1 million reads) for analytical validation. Clinical validation also showed 93% of plasma samples agreed with the clinical diagnostic test results when the diagnostic qPCR had a Ct < 33. The effect of different sequencing times was evaluated with the 19 h iSeq 100 paired end run, a more clinically palatable simulated iSeq 100 truncated run and the rapid 7 h MiniSeq platform. Our results demonstrate the ability to detect both DNA and RNA pathogens with low-depth sequencing and that iSeq 100 and MiniSeq platforms are compatible with unbiased low-depth metagenomics identification with the HostEL and AmpRE workflow.

6.
Blood ; 141(25): 3078-3090, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-36796022

RESUMEN

Adenosine-to-inosine RNA editing, which is catalyzed by adenosine deaminases acting on RNA (ADAR) family of enzymes, ADAR1 and ADAR2, has been shown to contribute to multiple cancers. However, other than the chronic myeloid leukemia blast crisis, relatively little is known about its role in other types of hematological malignancies. Here, we found that ADAR2, but not ADAR1 and ADAR3, was specifically downregulated in the core-binding factor (CBF) acute myeloid leukemia (AML) with t(8;21) or inv(16) translocations. In t(8;21) AML, RUNX1-driven transcription of ADAR2 was repressed by the RUNX1-ETO additional exon 9a fusion protein in a dominant-negative manner. Further functional studies confirmed that ADAR2 could suppress leukemogenesis specifically in t(8;21) and inv16 AML cells dependent on its RNA editing capability. Expression of 2 exemplary ADAR2-regulated RNA editing targets coatomer subunit α and component of oligomeric Golgi complex 3 inhibits the clonogenic growth of human t(8;21) AML cells. Our findings support a hitherto, unappreciated mechanism leading to ADAR2 dysregulation in CBF AML and highlight the functional relevance of loss of ADAR2-mediated RNA editing to CBF AML.


Asunto(s)
Factores de Unión al Sitio Principal , Leucemia Mieloide Aguda , Humanos , Regulación hacia Abajo , Factores de Unión al Sitio Principal/metabolismo , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Edición de ARN , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Leucemia Mieloide Aguda/genética , Adenosina/metabolismo
8.
Artículo en Inglés | MEDLINE | ID: mdl-35206290

RESUMEN

Older people are increasingly dependent on others to support their daily activities due to geriatric symptoms such as dementia. Some of them stay in long-term care facilities. Elderly people with night wandering behaviour may lose their way, leading to a significant risk of injuries. The eNightLog system was developed to monitor the night-time bedside activities of older people in order to help them cope with this issue. It comprises a 3D time-of-flight near-infrared sensor and an ultra-wideband sensor for detecting human presence and to determine postures without a video camera. A threshold-based algorithm was developed to classify different activities, such as leaving the bed. The system is able to send alarm messages to caregivers if an elderly user performs undesirable activities. In this study, 17 sets of eNightLog systems were installed in an elderly hostel with 17 beds in 9 bedrooms. During the three-month field test, 26 older people with different periods of stay were included in the study. The accuracy, sensitivity and specificity of detecting non-assisted bed-leaving events was 99.8%, 100%, and 99.6%, respectively. There were only three false alarms out of 2762 bed-exiting events. Our results demonstrated that the eNightLog system is sufficiently accurate to be applied in the hostel environment. Machine learning with instance segmentation and online learning will enable the system to be used for widely different environments and people, with improvements to be made in future studies.


Asunto(s)
Lechos , Cuidadores , Anciano , Algoritmos , Humanos , Aprendizaje Automático , Monitoreo Fisiológico
9.
Cancers (Basel) ; 14(2)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35053569

RESUMEN

Progression to metastatic disease occurs in about half of all men who develop prostate cancer (PC), one of the most common cancers in men worldwide. Androgen deprivation therapy has been the mainstay therapy for patients with metastatic PC (mPC) since the 1940s. In the last decade, there has been unprecedented advancement in systemic therapies, e.g., taxane, androgen-signalling pathway inhibitors, and biomarker-driven targeted therapies for various stages of disease, resulting in overall survival improvement. Adding to ongoing controversies over how best to treat these patients is the recognition that ethnicity may influence prognosis and outcomes. This review discusses recent evidence for the impacts of Asian ethnicity specifically, which includes environmental, sociocultural, and genetic factors, on the approach to pharmacological management of mPC. Clear inter-ethnic differences in drug tolerability, serious adverse events (AEs), and genetic heterogeneity must all be considered when dosing and scheduling for treatment, as well as designing future precision studies in PC.

10.
Artículo en Inglés | MEDLINE | ID: mdl-36612490

RESUMEN

Swallowing disorders, especially dysphagia, might lead to malnutrition and dehydration and could potentially lead to fatal aspiration. Benchmark swallowing assessments, such as videofluoroscopy or endoscopy, are expensive and invasive. Wearable technologies using acoustics and accelerometric sensors could offer opportunities for accessible and home-based long-term assessment. Identifying valid swallow events is the first step before enabling the technology for clinical applications. The objective of this review is to summarize the evidence of using acoustics-based and accelerometric-based wearable technology for swallow detection, in addition to their configurations, modeling, and assessment protocols. Two authors independently searched electronic databases, including PubMed, Web of Science, and CINAHL. Eleven (n = 11) articles were eligible for review. In addition to swallowing events, non-swallowing events were also recognized by dry (saliva) swallowing, reading, yawning, etc., while some attempted to classify the types of swallowed foods. Only about half of the studies reported that the device attained an accuracy level of >90%, while a few studies reported poor performance with an accuracy of <60%. The reviewed articles were at high risk of bias because of the small sample size and imbalanced class size problem. There was high heterogeneity in assessment protocol that calls for standardization for swallowing, dry-swallowing and non-swallowing tasks. There is a need to improve the current wearable technology and the credibility of relevant research for accurate swallowing detection before translating into clinical screening for dysphagia and other swallowing disorders.


Asunto(s)
Trastornos de Deglución , Humanos , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/etiología , Deglución , Endoscopía , Acústica
11.
Sensors (Basel) ; 21(16)2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34450994

RESUMEN

Surveillance of sleeping posture is essential for bed-ridden patients or individuals at-risk of falling out of bed. Existing sleep posture monitoring and classification systems may not be able to accommodate the covering of a blanket, which represents a barrier to conducting pragmatic studies. The objective of this study was to develop an unobtrusive sleep posture classification that could accommodate the use of a blanket. The system uses an infrared depth camera for data acquisition and a convolutional neural network to classify sleeping postures. We recruited 66 participants (40 men and 26 women) to perform seven major sleeping postures (supine, prone (head left and right), log (left and right) and fetal (left and right)) under four blanket conditions (thick, medium, thin, and no blanket). Data augmentation was conducted by affine transformation and data fusion, generating additional blanket conditions with the original dataset. Coarse-grained (four-posture) and fine-grained (seven-posture) classifiers were trained using two fully connected network layers. For the coarse classification, the log and fetal postures were merged into a side-lying class and the prone class (head left and right) was pooled. The results show a drop of overall F1-score by 8.2% when switching to the fine-grained classifier. In addition, compared to no blanket, a thick blanket reduced the overall F1-scores by 3.5% and 8.9% for the coarse- and fine-grained classifiers, respectively; meanwhile, the lowest performance was seen in classifying the log (right) posture under a thick blanket, with an F1-score of 72.0%. In conclusion, we developed a system that can classify seven types of common sleeping postures under blankets and achieved an F1-score of 88.9%.


Asunto(s)
Aprendizaje Profundo , Ropa de Cama y Ropa Blanca , Femenino , Humanos , Masculino , Redes Neurales de la Computación , Postura , Sueño
12.
Elife ; 102021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-34075878

RESUMEN

High spliceosome activity is a dependency for cancer cells, making them more vulnerable to perturbation of the splicing machinery compared to normal cells. To identify splicing factors important for prostate cancer (PCa) fitness, we performed pooled shRNA screens in vitro and in vivo. Our screens identified heterogeneous nuclear ribonucleoprotein M (HNRNPM) as a regulator of PCa cell growth. RNA- and eCLIP-sequencing identified HNRNPM binding to transcripts of key homeostatic genes. HNRNPM binding to its targets prevents aberrant exon inclusion and backsplicing events. In both linear and circular mis-spliced transcripts, HNRNPM preferentially binds to GU-rich elements in long flanking proximal introns. Mimicry of HNRNPM-dependent linear-splicing events using splice-switching-antisense-oligonucleotides was sufficient to inhibit PCa cell growth. This suggests that PCa dependence on HNRNPM is likely a result of mis-splicing of key homeostatic coding and non-coding genes. Our results have further been confirmed in other solid tumors. Taken together, our data reveal a role for HNRNPM in supporting cancer cell fitness. Inhibition of HNRNPM activity is therefore a potential therapeutic strategy in suppressing growth of PCa and other solid tumors.


Asunto(s)
Adenocarcinoma/metabolismo , Proliferación Celular , Ribonucleoproteína Heterogénea-Nuclear Grupo M/metabolismo , Neoplasias de la Próstata/metabolismo , Empalme del ARN , ARN Circular/biosíntesis , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Ribonucleoproteína Heterogénea-Nuclear Grupo M/genética , Humanos , Masculino , Ratones SCID , Células PC-3 , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , ARN Circular/genética , Carga Tumoral , Células Tumorales Cultivadas
13.
Mol Ther ; 29(11): 3258-3273, 2021 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33974998

RESUMEN

Dysregulated adenosine-to-inosine (A-to-I) RNA editing is implicated in various cancers. However, no available RNA editing inhibitors have so far been developed to inhibit cancer-associated RNA editing events. Here, we decipher the RNA secondary structure of antizyme inhibitor 1 (AZIN1), one of the best-studied A-to-I editing targets in cancer, by locating its editing site complementary sequence (ECS) at the 3' end of exon 12. Chemically modified antisense oligonucleotides (ASOs) that target the editing region of AZIN1 caused a substantial exon 11 skipping, whereas ECS-targeting ASOs effectively abolished AZIN1 editing without affecting splicing and translation. We demonstrate that complete 2'-O-methyl (2'-O-Me) sugar ring modification in combination with partial phosphorothioate (PS) backbone modification may be an optimal chemistry for editing inhibition. ASO3.2, which targets the ECS, specifically inhibits cancer cell viability in vitro and tumor incidence and growth in xenograft models. Our results demonstrate that this AZIN1-targeting, ASO-based therapeutics may be applicable to a wide range of tumor types.


Asunto(s)
Proteínas Portadoras/genética , Marcación de Gen , Edición de ARN , Animales , Secuencia de Bases , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/genética , Modelos Animales de Enfermedad , Exones , Regulación Neoplásica de la Expresión Génica , Marcación de Gen/métodos , Terapia Genética/métodos , Humanos , Ratones , Neoplasias/genética , Neoplasias/terapia , Oligonucleótidos Antisentido/genética , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Asia Pac J Clin Oncol ; 17 Suppl 3: 39-47, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33860642

RESUMEN

INTRODUCTION: Asian prostate cancer (PC) patients are particularly susceptible to docetaxel-related febrile neutropenia (FN). We evaluated primary granulocyte colony-stimulating factor (GCSF) for preventing FN in Chinese patients with metastatic hormone-sensitive PC (mHSPC) and castration-resistant PC (mCRPC). PATIENTS AND METHODS: Data from two cohorts of 377 Chinese patients with mHSPC (100; 26.5%) and mCRPC (277; 73.5%) treated with docetaxel at six public oncology centres were analysed with multivariate regression. Primary GCSF prophylaxis was defined as administration within 5 days of starting docetaxel. The primary outcome was FN within 21 days of the first docetaxel cycle (1st FN). RESULTS: Primary GCSF was given to 71 (18.8%) patients. FN occurred in 61 patients (16.2%) including 37 (9.8%) during the first cycle. Among patients who developed 1st cycle FN (n = 37) or not (n = 340), 2 and 69 received primary GCSF (5.4 vs. 20.3%, P = .03). Primary GCSF was associated with an overall reduced risk of 1st cycle FN (odds ratio [OR] = 0.22; 95% confidence interval [CI]: 0.05-0.96, P = .04), and similar trends were observed in the mHSPC (OR = 0.36, P = .35) and mCRPC (OR = 0.16, P = .08) subgroups. Poor Eastern Cooperative Oncology Group performance status (>1) was associated with an increased risk of 1st FN (OR = 3.90; 95% CI: 1.66-9.13, P = .002). CONCLUSIONS: To alleviate the risk of docetaxel-related FN, primary GCSF prophylaxis is suggested for Asian mCRPC and mHSPC patients, particularly those with poor performance status.


Asunto(s)
Docetaxel/efectos adversos , Neutropenia Febril/inducido químicamente , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , China , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Estudios Retrospectivos
15.
Asia Pac J Clin Oncol ; 17 Suppl 3: 48-54, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33860643

RESUMEN

AIM: In response to the fast-developing coronavirus disease 2019 (COVID-19) pandemic, special arrangement and coordination are urgently required in the interdisciplinary care of patients across different medical specialties. This article provides recommendations on the management of different stages of localized or metastatic prostate cancer (PC) amid this pandemic. METHODS: The Hong Kong Urological Association and Hong Kong Society of Uro-oncology formed a joint discussion panel, which consisted of six urologists and six clinical oncologists with extensive experience in the public and private sectors. Following an evidence-based approach, the latest relevant publications were searched and reviewed, before proceeding to a structured discussion of relevant clinical issues. RESULTS: The joint panel provided recommendations for PC management during the pandemic, in terms of general considerations, diagnostic procedures, different disease stages, treatment modules, patient support, and interdisciplinary collaboration. The overall goal was to minimize the risk of infection while avoiding unnecessary delays and compromises in management outcomes. Practical issues during the pandemic were addressed such as the use of invasive diagnostic procedures, robotic-assisted laparoscopic prostatectomy, hypofractionated radiotherapy, and prolonged androgen deprivation therapy. The recommendations were explicated in the context of Hong Kong, a highly populated international city, in relation to the latest international guidelines and evidence. CONCLUSION: A range of recommendations on the management of PC patients during the COVID-19 pandemic was developed. Urologists, oncologists, and physicians treating PC patients may refer to them as practical guidance.


Asunto(s)
COVID-19/epidemiología , Neoplasias de la Próstata/terapia , SARS-CoV-2 , Antagonistas de Andrógenos/uso terapéutico , Hong Kong/epidemiología , Humanos , Masculino , Oncología Médica , Prostatectomía , Neoplasias de la Próstata/patología , Sociedades Médicas
16.
Asia Pac J Clin Oncol ; 17 Suppl 3: 12-26, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33860645

RESUMEN

BACKGROUND: To update the Hong Kong Urological Association-Hong Kong Society of Uro-Oncology consensus statements on the management of advanced prostate cancer, the same panelists as in the previous consensus panel held a series of meetings to discuss updated clinical evidence and experiences. METHODS: The previous consensus statements were retained, deleted, or revised, and new statements were added. At the final meeting, all statements were reviewed and amended as appropriate, followed by panel voting. RESULTS: There were significant changes and additions to the previous consensus statements, primarily driven by the advances in androgen receptor signaling inhibitors, treatment sequencing in metastatic castration-resistant prostate cancer, and increasing recognition of oligometastatic prostate cancer since the introduction of prostate-specific membrane antigen positron emission tomography. In this update, a total of 59 consensus statements were accepted and established. CONCLUSIONS: The consensus panel updated consensus statements on the management of advanced prostate cancer, aiming to allow physicians in the region to keep abreast of the recent evidence on optimal clinical practices.


Asunto(s)
Neoplasias de la Próstata/terapia , Urología/métodos , Historia del Siglo XXI , Hong Kong , Humanos , Masculino , Neoplasias de la Próstata/patología
18.
Sensors (Basel) ; 21(3)2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33498590

RESUMEN

Wandering is a common behavioral disorder in the community-dwelling elderly. More than two-thirds of caregivers believe that wandering would cause falls. While physical restraint is a common measure to address wandering, it could trigger challenging behavior in approximately 80% of the elderly with dementia. This study aims to develop a virtual restraint using a night monitoring system (eNightLog) to provide a safe environment for the elderly and mitigate the caregiver burden. The eNightLog system consisted of remote sensors, including a near infra-red 3D time-of-flight sensor and ultrawideband sensors. An alarm system was controlled by customized software and algorithm based on the respiration rate and body posture of the elderly. The performance of the eNightLog system was evaluated in both single and double bed settings by comparing to that of a pressure mat and an infrared fence system, under simulated bed-exiting scenarios. The accuracy and precision for the three systems were 99.0%, 98.8%, 85.9% and 99.2%, 97.8%, 78.6%, respectively. With higher accuracy, precision, and a lower false alarm rate, eNightLog demonstrated its potential as an alternative to physical restraint to remedy the workload of the caregivers and the psychological impact of the elderly.


Asunto(s)
Monitoreo Fisiológico , Conducta Errante , Accidentes por Caídas , Anciano , Cuidadores , Humanos , Vida Independiente
19.
J Hepatol ; 74(1): 135-147, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32693003

RESUMEN

BACKGROUND & AIMS: RNA editing introduces nucleotide changes in RNA sequences. Recent studies have reported that aberrant adenosine-to-inosine RNA editing is implicated in cancers. Until now, very few functionally important protein-recoding editing targets have been discovered. Here, we investigated the role of a recently discovered protein-recoding editing target COPA (coatomer subunit α) in hepatocellular carcinoma (HCC). METHODS: Clinical implication of COPA editing was studied in a cohort of 125 HCC patients. CRISPR/Cas9-mediated knockout of the editing site complementary sequence (ECS) was used to delete edited COPA transcripts endogenously. COPA editing-mediated change in its transcript or protein stability was investigated upon actinomycin D or cycloheximide treatment, respectively. Functional difference in tumourigenesis between wild-type and edited COPA (COPAWTvs. COPAI164V) and the exact mechanisms were also studied in cell models and mice. RESULTS: ADAR2 binds to double-stranded RNA formed between edited exon 6 and the ECS at intron 6 of COPA pre-mRNA, causing an isoleucine-to-valine substitution at residue 164. Reduced editing of COPA is implicated in the pathogenesis of HCC, and more importantly, it may be involved in many cancer types. Upon editing, COPAWT switches from a tumour-promoting gene to a tumour suppressor that has a dominant-negative effect. Moreover, COPAI164V may undergo protein conformational change and therefore become less stable than COPAWT. Mechanistically, COPAI164V may deactivate the PI3K/AKT/mTOR pathway through downregulation of caveolin-1 (CAV1). CONCLUSIONS: We uncover an RNA editing-associated mechanism of hepatocarcinogenesis by which downregulation of ADAR2 caused the loss of tumour suppressive COPAI164V and concurrent accumulation of tumour-promoting COPAWT in tumours; a rapid degradation of COPAI164V protein and hyper-activation of the PI3K/AKT/mTOR pathway further promote tumourigenesis. LAY SUMMARY: RNA editing is a process in which RNA is changed after it is made from DNA, resulting in an altered gene product. In this study, we found that RNA editing of a gene known as coatomer subunit α (COPA) is lower in tumour samples and discovered that this editing process changes COPA protein from a tumour-promoting form to a tumour-suppressive form. Loss of the edited COPA promotes the development of liver cancer.


Asunto(s)
Carcinogénesis/genética , Carcinoma Hepatocelular , Proteína Coatómero/genética , Regulación de la Expresión Génica/genética , Neoplasias Hepáticas , Edición de ARN/genética , Adenosina Desaminasa/genética , Animales , Secuencia de Bases , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Caveolina 1/metabolismo , Línea Celular , Regulación hacia Abajo , Genes Supresores de Tumor , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Ratones , Proteínas de Neoplasias , Estabilidad Proteica , Proteínas de Unión al ARN/genética
20.
Sci Adv ; 6(25): eaba5136, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32596459

RESUMEN

RNA editing introduces nucleotide changes in RNA sequences. Recent studies have reported that aberrant A-to-I RNA editing profiles are implicated in cancers. Albeit changes in expression and activity of ADAR genes are thought to have been responsible for the dysregulated RNA editome in diseases, they are not always correlated, indicating the involvement of secondary regulators. Here, we uncover DAP3 as a potent repressor of editing and a strong oncogene in cancer. DAP3 mainly interacts with the deaminase domain of ADAR2 and represses editing via disrupting association of ADAR2 with its target transcripts. PDZD7, an exemplary DAP3-repressed editing target, undergoes a protein recoding editing at stop codon [Stop →Trp (W)]. Because of editing suppression by DAP3, the unedited PDZD7WT, which is more tumorigenic than edited PDZD7Stop518W, is accumulated in tumors. In sum, cancer cells may acquire malignant properties for their survival advantage through suppressing RNA editome by DAP3.


Asunto(s)
Adenosina , Proteínas Reguladoras de la Apoptosis , Neoplasias , Proteínas de Unión al ARN , Adenosina/genética , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Humanos , Inosina/genética , Inosina/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , ARN/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
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