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1.
Semin Cancer Biol ; 74: 105-120, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33989735

RESUMEN

Cancer has risen up to be a major cause of mortality worldwide over the past decades. Despite advancements in cancer screening and diagnostics, a significant number of cancers are still diagnosed at a late stage with poor prognosis. Hence, the discovery of reliable and accurate methods to diagnose cancer early would be of great help in reducing cancer mortality. Extracellular vesicles (EVs) are phospholipid vesicles found in many biofluids and are released by almost all types of cells. In recent years, using EVs as cancer biomarkers has garnered attention as a novel technique of cancer diagnosis. Compared with traditional tissue biopsy, there are many advantages that this novel diagnostic tool presents - it is less invasive, detects early-stage asymptomatic cancers, and allows for monitoring of tumour progression. As such, EV biomarkers have great potential in improving the diagnostic accuracy of cancers and guiding subsequent therapeutic decisions. Efficient isolation and accurate characterization of EVs are essential for reliable outcomes of clinical application. However, these are complicated by the size and biomolecular diversity of EVs. In this review, we present an analysis and evaluation of the current techniques of EV isolation and characterization, as well as discuss the potential EV biomarkers for specific types of cancer. Taken together, EV biomarkers have a lot of potential as a novel method in cancer diagnostics and diagnosis. However, more work is still needed to streamline the purification, characterization and biomarker identification process to ensure optimal outcomes for patients.


Asunto(s)
Biomarcadores de Tumor/análisis , Vesículas Extracelulares , Neoplasias/diagnóstico , Animales , Humanos , Biopsia Líquida/métodos
2.
Breast Cancer Res Treat ; 188(3): 779-788, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33948777

RESUMEN

PURPOSE: To identify a structure to explain the relationship between socio-clinico factors, necessity-concerns beliefs, and perceived barriers to adherence with adjuvant endocrine therapy (AET) amongst women with breast cancer. METHODS: Participants were 244 patients with early-stage breast cancer recruited from two tertiary hospitals from May 2015 to December 2018 who completed questionnaires on medication adherence (Simplified Medication Adherence Questionnaire), necessity-concerns beliefs (Beliefs about Medicine Questionnaire), and barriers to adherence (Adherence Starts with Knowledge Questionnaire). Socio-clinico variables were collected via interview and medical records review. Structural equation modelling was applied to examine the relationships between these variables and possible mediating effects of necessity-concerns beliefs on adherence to AET. RESULTS: The median age of the study participants was 61 (range 32-80) years and the median duration on AET was 1.6 (IQR 1.2-2.6) years. Adherence was positively associated with age (ß = 0.145, 95% CI: 0.011 to 0.279, p = 0.034) and negatively associated with barriers (ß = - 0.381, 95% CI: - 0.511 to - 0.251, p < 0.001). There was no effect of Necessity (ß = 0.006, 95% CI: - 0.145 to 0.158, p = 0.933) or Concerns (ß = 0.041, 95% CI: - 0.117 to 0.199, p = 0.614) on adherence. Necessity-concerns beliefs were also not significant mediators in the relationship between socio-clinico factors and medication adherence. CONCLUSIONS: Older age and lower barriers to adherence were associated with higher adherence scores. Necessity-concerns beliefs did not have a significant effect on adherence as majority of the patients identified forgetfulness as a reason for non-adherence.


Asunto(s)
Antineoplásicos Hormonales , Neoplasias de la Mama , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Terapia Combinada , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Análisis de Clases Latentes , Cumplimiento de la Medicación , Persona de Mediana Edad , Encuestas y Cuestionarios
3.
Pharmacol Res ; 156: 104686, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32068118

RESUMEN

Cell cycle dysregulation, characterised by aberrant activation of cyclin dependent kinases (CDKs), is a hallmark of cancer. After years of research on the first and second generations of less selective CDK inhibitors with unfavourable clinical activity and toxicity profiles, CDK4/6 inhibitors become the first and only class of highly specific CDK inhibitors being approved for cancer treatment to date. CDK4/6 inhibitors have transformed the treatment paradigm of estrogen receptor-positive (ER+) breast cancer, dramatically improving the survival outcomes of these patients when incorporated with conventional endocrine therapies in both the first and later-line settings. Currently, the efficacies of CDK4/6 inhibitors in other breast cancer subtypes and cancers are being actively explored. All three CDK4/6 inhibitors have demonstrated very similar clinical efficacies. However, being the least similar structurally, abemaciclib is the only CDK4/6 inhibitor with single agent activity in refractory metastatic ER + breast cancer, the ability to cross the blood brain barrier efficiently, and a distinct toxicity profile of lower myelosuppression such that it can be dosed continuously. Here, we further discuss the distinguishing features of abemaciclib as compared to the other two CDK4/6 inhibitors, palbociclib and ribociclib. Besides being the most potent inhibitor of CDK4/6, abemaciclib exhibits a wider selectivity towards other CDKs and kinases, and functions through additional mechanisms of action besides inducing G1 cell cycle arrest, in a dose dependent manner. Hence, abemaciclib has the potential to act independently of the CDK4/6-cyclin D-RB pathway, resulting in crucial implications on the possibly expanded clinical indications and predictive biomarkers of abemaciclib, in contrast to the other CDK4/6 inhibitors. The current status of preclinical evidence and clinical studies of abemaciclib as a single agent and in combination treatment in breast and other cancers, together with its potential predictive biomarkers, is also summarised in this review.


Asunto(s)
Aminopiridinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bencimidazoles/uso terapéutico , Proliferación Celular/efectos de los fármacos , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Aminopiridinas/efectos adversos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bencimidazoles/efectos adversos , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/metabolismo , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Terapia Molecular Dirigida , Neoplasias/enzimología , Neoplasias/patología , Inhibidores de Proteínas Quinasas/efectos adversos , Transducción de Señal , Resultado del Tratamiento
4.
Cancer ; 125(11): 1789-1798, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30933320

RESUMEN

Deguelin is a rotenoid compound that exists in abundant quantities in the bark, roots, and leaves of the Leguminosae family of plants. An analysis of evidence from both in vitro and in vivo studies suggests that deguelin displays potent anticancer activity against multiple cancer types and exhibits chemopreventive potential in Akt-inducible transgenic mouse models. Deguelin appears to impede carcinogenesis by enhancing cell apoptosis and hindering malignant transformation and tumor cell propagation. Crucial oncogenic pathways likely targeted by deguelin include the epithelial-to-mesenchymal transition; angiogenesis-related pathways; and the phosphoinositide 3-kinase/Akt, Wnt, epidermal growth factor receptor, c-Met, and hedgehog signal transduction cascades. This review article provides a comprehensive summary of current preclinical research featuring deguelin as a leading chemotherapeutic and chemopreventive compound, and it highlights the importance of identifying companion molecular biomarkers and performing systemic pharmacokinetic studies for accelerating the process of developing deguelin as a clinical anticancer agent.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Desarrollo de Medicamentos , Neoplasias/tratamiento farmacológico , Rotenona/análogos & derivados , Animales , Humanos , Rotenona/uso terapéutico
5.
BMC Med ; 16(1): 104, 2018 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-29986700

RESUMEN

BACKGROUND: Genotype-guided warfarin dosing has been shown in some randomized trials to improve anticoagulation outcomes in individuals of European ancestry, yet its utility in Asian patients remains unresolved. METHODS: An open-label, non-inferiority, 1:1 randomized trial was conducted at three academic hospitals in South East Asia, involving 322 ethnically diverse patients newly indicated for warfarin (NCT00700895). Clinical follow-up was 90 days. The primary efficacy measure was the number of dose titrations within the first 2 weeks of therapy, with a mean non-inferiority margin of 0.5 over the first 14 days of therapy. RESULTS: Among 322 randomized patients, 269 were evaluable for the primary endpoint. Compared with traditional dosing, the genotype-guided group required fewer dose titrations during the first 2 weeks (1.77 vs. 2.93, difference -1.16, 90% CI -1.48 to -0.84, P < 0.001 for both non-inferiority and superiority). The percentage of time within the therapeutic range over 3 months and median time to stable international normalized ratio (INR) did not differ between the genotype-guided and traditional dosing groups. The frequency of dose titrations (incidence rate ratio 0.76, 95% CI 0.67 to 0.86, P = 0.001), but not frequency of INR measurements, was lower at 1, 2, and 3 months in the genotype-guided group. The proportions of patients who experienced minor or major bleeding, recurrent venous thromboembolism, or out-of-range INR did not differ between both arms. For predicting maintenance doses, the pharmacogenetic algorithm achieved an R2 = 42.4% (P < 0.001) and mean percentage error of -7.4%. CONCLUSIONS: Among Asian adults commencing warfarin therapy, a pharmacogenetic algorithm meets criteria for both non-inferiority and superiority in reducing dose titrations compared with a traditional dosing approach, and performs well in prediction of actual maintenance doses. These findings imply that clinicians may consider applying a pharmacogenetic algorithm to personalize initial warfarin dosages in Asian patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT00700895 . Registered on June 19, 2008.


Asunto(s)
Anticoagulantes/uso terapéutico , Dosis Máxima Tolerada , Warfarina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/farmacología , Pueblo Asiatico , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Warfarina/administración & dosificación , Warfarina/farmacología , Adulto Joven
6.
BMC Cancer ; 18(1): 727, 2018 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-29986672

RESUMEN

BACKGROUND: Medication adherence refers to whether a patient takes medication according to the frequency prescribed, or continues to take a prescribed medication. Inadequate adherence to medication may cause alterations in risk-benefit ratios, resulting in reduced benefits, increased risks or both, and is significantly associated with adverse clinical outcomes and higher healthcare costs. We aim to examine the effect of a computer generated short message service (SMS) reminder in improving medication adherence, and inhibiting the aromatisation process amongst breast cancer women receiving oral aromatase inhibitor therapy. METHODS/DESIGN: In this randomised controlled trial, eligible patients will be equally allocated to receive either SMS reminder or standard care. The former receives weekly SMS reminder to take medication while the latter does not receive any. The primary endpoint of medication adherence at 1-year is assessed using the Simplified Medication Adherence Questionnaire, and compared using the χ2 test. Adjustment for baseline covariate and potential confounders will be made using the logistic regression. Secondary outcomes involving estrone and androstenedione levels will be compared using the analysis of covariance, whereas the estradiol levels (< 18.4 pmol/L versus ≥18.4 pmol/L) will be compared using the χ2 test, and the logistic regression. Further, the assessment of knowledge, attitude, behaviour, and barriers and facilitating factors of medication adherence will be made via logistic regression. DISCUSSION: This will be the first study to evaluate short-term clinical outcomes from SMS reminder for breast cancer patients on aromatase inhibitor therapy. Random allocation to SMS reminder or control arm ensures that patients in both arms will be comparable with respect to demographic and clinical characteristics, and any difference in outcomes can be attributed to the intervention. Participants are not blinded to the assignment of intervention, thus there may be potential for bias in outcome assessments. TRIAL REGISTRATION: NCT02524548 . Retrospectively registered on 17 August 2015.


Asunto(s)
Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Cumplimiento de la Medicación , Envío de Mensajes de Texto , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Cancer Sci ; 107(2): 173-80, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26663719

RESUMEN

Hepatic dysfunction may modify the safety profile and pharmacokinetics of docetaxel in cancer patients, but no validated guideline exists to guide dose modification necessitated by this uncommon comorbidity. We carried out the first prospective study of a personalized dosage regimen for cancer patients with liver dysfunction treated with docetaxel. Weekly dosages were stratified by hepatic dysfunction classification as such: Category 1, normal; Category 2, mild--alkaline phosphatase, aspartate aminotransferase, and/or alanine aminotransferase ≤5× upper limit of normal (ULN), and total bilirubin within normal range; and Category 3, moderate--any alkaline phosphatase, and aspartate aminotransferase or alanine aminotransferase ≤5-10× ULN, and/or total bilirubin ≤1-1.5× ULN. Category 1, 2 and 3 patients received starting dosages of 40, 30, and 20 mg/m(2) docetaxel, respectively. Pharmacokinetics were evaluated on day 1 and 8 of the first treatment cycle, and entered into a multilevel model to delineate interindividual and interoccasion variability. Adverse event evaluation was carried out weekly for two treatment cycles. We found that docetaxel clearance was significantly different between patient categories (P < 0.001). Median clearance was 22.8, 16.4, and 11.3 L/h/m(2) in Categories 1, 2, and 3, respectively, representing 28% and 50% reduced clearance in mild and moderate liver dysfunction patients, respectively. However, docetaxel exposure (area under the concentration-time curve) and docetaxel-induced neutropenia (nadir and the maximum percentage decrease in neutrophil count) were not significantly different between categories. Median area under the concentration-time curve was 1.74, 1.83, and 1.77 mg·h/L in Categories 1, 2, and 3, respectively. The most common Grade 3/4 toxicity was neutropenia (30.0%). An unplanned comparison with the Child-Pugh and National Cancer Institute Organ Dysfunction Working Group grouping systems suggests that the proposed classification system appears to more effectively discriminate patients by docetaxel clearance and dose requirements. (ClinicalTrials.gov registration no. NCT00703378).


Asunto(s)
Antineoplásicos/administración & dosificación , Hígado/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Taxoides/administración & dosificación , Adulto , Anciano , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Área Bajo la Curva , Pueblo Asiatico , Docetaxel , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hepatopatías/etiología , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Curva ROC , Taxoides/efectos adversos , Taxoides/farmacocinética
8.
J Transl Med ; 13: 57, 2015 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-25889309

RESUMEN

BACKGROUND: Regorafenib, a multi-kinase inhibitor, is used in the treatment of patients with metastatic colorectal cancer refractory to standard therapy. However, this benefit was limited to 1.4 months improvement in overall survival, with more than half of patients experiencing grade 3 to 4 adverse events. We aim to elucidate the pharmacodynamic effects of regorafenib in metastatic colorectal cancer and discover potential biomarkers that may predict clinical benefit. METHODS: Patients with metastatic colorectal adenocarcinoma refractory to standard therapy with tumours amenable to biopsy were eligible for the study. Regorafenib was administered orally at 160 mg daily for 3 out of 4 weeks with tumour assessment every 2 cycles. Metabolic response was assessed by FDG PET-CT scans (pre-treatment and day 15); paired tumour biopsies (pre-treatment and day 21 post-treatment) were sampled for immunohistochemistry and proteomic profiling analyses. Plasma circulating cell free DNA was quantified serially before and after treatment. RESULTS: There were 2(6%) partial responses out of 35 patients, and 8(23%) patients had stable disease for more than 7 months. Adverse event profile was similar to reported data. Recurrent somatic mutations in K-RAS, PIK3CA and BRAF were detected in plasma circulating cell free DNA in 14 patients; some mutations were not found in archival tumour. Total plasma circulating cell free DNA inversely correlated with progression free survival (PFS), and presence of KRAS mutations associated with shorter PFS. Immunohistochemistry of pre- and post- treatment biopsies showed majority of patients had downregulation of phosphorylated-VEGFR2, podoplanin, phosphorylated-AKT, Ki-67 and upregulation of the MEK-ERK axis, phosphorylated-C-MET, phosphorylated-SRC, phosphorylated-STAT3 and phosphorylated-JUN. Proteomic analysis of fine needle tumour aspirates showed down-regulation of PI3K was associated with longer PFS. CONCLUSION: Plasma circulating cell free DNA may yield potential predictive biomarkers of regorafenib treatment. Downregulation of the PI3K-AKT axis may be an important predictor of clinical benefit.


Asunto(s)
Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/tratamiento farmacológico , ADN de Neoplasias/sangre , Compuestos de Fenilurea/uso terapéutico , Piridinas/uso terapéutico , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Sistema Libre de Células , Fosfatidilinositol 3-Quinasa Clase I , Análisis Mutacional de ADN , Demografía , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Compuestos de Fenilurea/efectos adversos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteómica , Piridinas/efectos adversos , Resultado del Tratamiento
9.
Exp Hematol Oncol ; 13(1): 40, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615034

RESUMEN

Glioblastoma (GBM) is a fatal brain tumour that is traditionally diagnosed based on histological features. Recent molecular profiling studies have reshaped the World Health Organization approach in the classification of central nervous system tumours to include more pathogenetic hallmarks. These studies have revealed that multiple oncogenic pathways are dysregulated, which contributes to the aggressiveness and resistance of GBM. Such findings have shed light on the molecular vulnerability of GBM and have shifted the disease management paradigm from chemotherapy to targeted therapies. Targeted drugs have been developed to inhibit oncogenic targets in GBM, including receptors involved in the angiogenic axis, the signal transducer and activator of transcription 3 (STAT3), the PI3K/AKT/mTOR signalling pathway, the ubiquitination-proteasome pathway, as well as IDH1/2 pathway. While certain targeted drugs showed promising results in vivo, the translatability of such preclinical achievements in GBM remains a barrier. We also discuss the recent developments and clinical assessments of targeted drugs, as well as the prospects of cell-based therapies and combinatorial therapy as novel ways to target GBM. Targeted treatments have demonstrated preclinical efficacy over chemotherapy as an alternative or adjuvant to the current standard of care for GBM, but their clinical efficacy remains hindered by challenges such as blood-brain barrier penetrance of the drugs. The development of combinatorial targeted therapies is expected to improve therapeutic efficacy and overcome drug resistance.

10.
Antioxid Redox Signal ; 41(4-6): 322-341, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38445392

RESUMEN

Significance: Reactive oxygen species (ROS) are generated during mitochondrial oxidative metabolism, and are tightly controlled through homeostatic mechanisms to maintain intracellular redox, regulating growth and proliferation in healthy cells. However, ROS production is perturbed in cancers where abnormal accumulation of ROS leads to oxidative stress and genomic instability, triggering oncogenic signaling pathways on one hand, while increasing oxidative damage and triggering ROS-dependent death signaling on the other. Recent Advances: Our review illuminates how critical interactions between ROS and oncogenic signaling, the tumor microenvironment, and DNA damage response (DDR) pathways have led to interest in ROS modulation as a means of enhancing existing anticancer strategies and developing new therapeutic opportunities. Critical Issues: ROS equilibrium exists via a delicate balance of pro-oxidant and antioxidant species within cells. "Antioxidant" approaches have been explored mainly in the form of chemoprevention, but there is insufficient evidence to advocate its routine application. More progress has been made via the "pro-oxidant" approach of targeting cancer vulnerabilities and inducing oxidative stress. Various therapeutic modalities have employed this approach, including direct ROS-inducing agents, chemotherapy, targeted therapies, DDR therapies, radiotherapy, and immunotherapy. Finally, emerging delivery systems such as "nanosensitizers" as radiotherapy enhancers are currently in development. Future Directions: While approaches designed to induce ROS have shown considerable promise in selectively targeting cancer cells and dealing with resistance to conventional therapies, most are still in early phases of development and challenges remain. Further research should endeavor to refine treatment strategies, optimize drug combinations, and identify predictive biomarkers of ROS-based cancer therapies.


Asunto(s)
Antineoplásicos , Neoplasias , Estrés Oxidativo , Especies Reactivas de Oxígeno , Humanos , Especies Reactivas de Oxígeno/metabolismo , Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Animales , Antioxidantes/uso terapéutico , Antioxidantes/metabolismo , Microambiente Tumoral/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Daño del ADN
11.
Theranostics ; 14(16): 6350-6369, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39431017

RESUMEN

Rationale: Growing evidence points to the tumor microenvironment's role in developing drug resistance. A key element of this microenvironment is inter-cellular communication, which includes the release of membrane-encapsulated vesicles containing various cargo, known as extracellular vesicles (EVs). Understanding how EVs contribute to acquired resistance holds significant clinical implications. Methods: Differential centrifugation-based methods were used to isolate EVs from established cell lines and human plasma. TMT labeling proteomics analysis of EVs revealed an abundance of metabolic transporter proteins. Increased expression of SLC1A5 in EVs of patient-derived plasma and cell lines rendered resistant to tyrosine kinase inhibitors and its relationship with progression-free survival was assessed using Kaplan-Meier survival plot. Gene knockdown and overexpression of SLC1A5 were used to validate its effect on Tyrosine kinase inhibitor (TKI) resistance. Co-culture assays using inserts was used to evaluate the effect of resistant EVs on normal fibroblasts and epithelial cells. Next, mouse-derived tumor slices (MDTS) were cultured in vitro to assess the effect of resistant EVs. Results: We report here that TKI-sensitive cells are rendered resistant upon incubation with EVs derived from TKI-resistant cell lines. Metabolic transporters, in particular SLC1A5 and SLC25A5, are upregulated in EVs derived from TKI-resistant cells and plasma from patients harbouring TKI-resistant tumors and in TKI-resistant cell lines. Furthermore, we also provide evidence for the increased abundance of pSTAT3 and the stemness marker ALDH1A1 upon EV-induced resistance. Notably, resistant EVs trigger phenotypic and functional switching of lung-derived fibroblasts into tumor-associated fibroblasts, significantly increasing their migratory and invasive capacities. Conclusions: Our findings support the role of metabolic transporters within tumor-derived EVs in reshaping the tumor microenvironment to promote therapy resistance, which could have potential diagnostic, prognostic, and therapeutic implications.


Asunto(s)
Resistencia a Antineoplásicos , Vesículas Extracelulares , Microambiente Tumoral , Humanos , Vesículas Extracelulares/metabolismo , Animales , Ratones , Línea Celular Tumoral , Metabolismo Energético , Inhibidores de Proteínas Quinasas/farmacología , Proteómica/métodos
12.
PLoS One ; 19(7): e0307818, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39058662

RESUMEN

INTRODUCTION: High grade astrocytic glioma (HGG) is a lethal solid malignancy with high recurrence rates and limited survival. While several cytotoxic agents have demonstrated efficacy against HGG, drug sensitivity testing platforms to aid in therapy selection are lacking. Patient-derived organoids (PDOs) have been shown to faithfully preserve the biological characteristics of several cancer types including HGG, and coupled with the experimental-analytical hybrid platform Quadratic Phenotypic Optimization Platform (QPOP) which evaluates therapeutic sensitivity at a patient-specific level, may aid as a tool for personalized medical decisions to improve treatment outcomes for HGG patients. METHODS: This is an interventional, non-randomized, open-label study, which aims to enroll 10 patients who will receive QPOP-guided chemotherapy at the time of first HGG recurrence following progression on standard first-line therapy. At the initial presentation of HGG, tumor will be harvested for primary PDO generation during the first biopsy/surgery. At the point of tumor recurrence, patients will be enrolled onto the main study to receive systemic therapy as second-line treatment. Subjects who undergo surgery at the time of recurrence will have a second harvest of tissue for PDO generation. Established PDOs will be subject to QPOP analyses to determine their therapeutic sensitivities to specific panels of drugs. A QPOP-guided treatment selection algorithm will then be used to select the most appropriate drug combination. The primary endpoint of the study is six-month progression-free survival. The secondary endpoints include twelve-month overall survival, RANO criteria and toxicities. In our radiological biomarker sub-study, we plan to evaluate novel radiopharmaceutical-based neuroimaging in determining blood-brain barrier permeability and to assess in vivo drug effects on tumor vasculature over time. TRIAL REGISTRATION: This trial was registered on 8th September 2022 with ClinicalTrials.gov Identifier: NCT05532397.


Asunto(s)
Neoplasias Encefálicas , Recurrencia Local de Neoplasia , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Astrocitoma/tratamiento farmacológico , Astrocitoma/patología , Astrocitoma/diagnóstico por imagen , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/diagnóstico por imagen , Clasificación del Tumor , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Organoides/efectos de los fármacos , Organoides/patología , Organoides/diagnóstico por imagen , Ensayos Clínicos como Asunto
13.
Cell Death Dis ; 15(5): 338, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744809

RESUMEN

Epitranscriptomic RNA modifications are crucial for the maintenance of glioma stem cells (GSCs), the most malignant cells in glioblastoma (GBM). 3-methylcytosine (m3C) is a new epitranscriptomic mark on RNAs and METTL8 represents an m3C writer that is dysregulated in cancer. Although METTL8 has an established function in mitochondrial tRNA (mt-tRNA) m3C modification, alternative splicing of METTL8 can also generate isoforms that localize to the nucleolus where they may regulate R-loop formation. The molecular basis for METTL8 dysregulation in GBM, and which METTL8 isoform(s) may influence GBM cell fate and malignancy remain elusive. Here, we investigated the role of METTL8 in regulating GBM stemness and tumorigenicity. In GSC, METTL8 is exclusively localized to the mitochondrial matrix where it installs m3C on mt-tRNAThr/Ser(UCN) for mitochondrial translation and respiration. High expression of METTL8 in GBM is attributed to histone variant H2AZ-mediated chromatin accessibility of HIF1α and portends inferior glioma patient outcome. METTL8 depletion impairs the ability of GSC to self-renew and differentiate, thus retarding tumor growth in an intracranial GBM xenograft model. Interestingly, METTL8 depletion decreases protein levels of HIF1α, which serves as a transcription factor for several receptor tyrosine kinase (RTK) genes, in GSC. Accordingly, METTL8 loss inactivates the RTK/Akt axis leading to heightened sensitivity to Akt inhibitor treatment. These mechanistic findings, along with the intimate link between METTL8 levels and the HIF1α/RTK/Akt axis in glioma patients, guided us to propose a HIF1α/Akt inhibitor combination which potently compromises GSC proliferation/self-renewal in vitro. Thus, METTL8 represents a new GBM dependency that is therapeutically targetable.


Asunto(s)
Glioblastoma , Subunidad alfa del Factor 1 Inducible por Hipoxia , Metiltransferasas , Células Madre Neoplásicas , Proteínas Proto-Oncogénicas c-akt , Metilación de ARN , Animales , Humanos , Ratones , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Carcinogénesis/genética , Carcinogénesis/patología , Carcinogénesis/metabolismo , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Metiltransferasas/metabolismo , Metiltransferasas/genética , Ratones Desnudos , Mitocondrias/metabolismo , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN de Transferencia/metabolismo , ARN de Transferencia/genética , Transducción de Señal , Metilación de ARN/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo
14.
Singapore Med J ; 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37675681

RESUMEN

Introduction: The most recent local study on the incidence of histological subtypes of all brain and spinal tumours treated surgically was published in 2000. In view of the outdated data, we investigated the presenting characteristics, histological subtypes and outcomes of adult patients who underwent surgery for brain or spinal tumours at our institution. Methods: A single-centre retrospective review of 501 patients who underwent surgery for brain or spinal tumours from 2016 to 2020 was conducted. The inclusion criteria were (a) patients who had a brain or spinal tumour that was histologically verified and (b) patients who were aged 18 years and above at the time of surgery. Results: Four hundred and thirty-five patients (86.8%) had brain tumours and 66 patients (13.2%) had spinal tumours. Patients with brain tumours frequently presented with cranial nerve palsy, headache and weakness, while patients with spinal tumours frequently presented with weakness, numbness and back pain. Overall, the most common histological types of brain and spinal tumours were metastases, meningiomas and tumours of the sellar region. The most common complications after surgery were cerebrospinal fluid leak, diabetes insipidus and urinary tract infection. In addition, 15.2% of the brain tumours and 13.6% of the spinal tumours recurred, while 25.7% of patients with brain tumours and 18.2% of patients with spinal tumours died. High-grade gliomas and metastases had the poorest survival and highest recurrence rates. Conclusion: This study serves as a comprehensive update of the epidemiology of brain and spinal tumours and could help guide further studies on brain and spinal tumours.

15.
BMJ Open ; 13(10): e077219, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37879700

RESUMEN

INTRODUCTION: Conventional interventional modalities for preserving or improving cognitive function in patients with brain tumour undergoing radiotherapy usually involve pharmacological and/or cognitive rehabilitation therapy administered at fixed doses or intensities, often resulting in suboptimal or no response, due to the dynamically evolving patient state over the course of disease. The personalisation of interventions may result in more effective results for this population. We have developed the CURATE.AI COR-Tx platform, which combines a previously validated, artificial intelligence-derived personalised dosing technology with digital cognitive training. METHODS AND ANALYSIS: This is a prospective, single-centre, single-arm, mixed-methods feasibility clinical trial with the primary objective of testing the feasibility of the CURATE.AI COR-Tx platform intervention as both a digital intervention and digital diagnostic for cognitive function. Fifteen patient participants diagnosed with a brain tumour requiring radiotherapy will be recruited. Participants will undergo a remote, home-based 10-week personalised digital intervention using the CURATE.AI COR-Tx platform three times a week. Cognitive function will be assessed via a combined non-digital cognitive evaluation and a digital diagnostic session at five time points: preradiotherapy, preintervention and postintervention and 16-weeks and 32-weeks postintervention. Feasibility outcomes relating to acceptability, demand, implementation, practicality and limited efficacy testing as well as usability and user experience will be assessed at the end of the intervention through semistructured patient interviews and a study team focus group discussion at study completion. All outcomes will be analysed quantitatively and qualitatively. ETHICS AND DISSEMINATION: This study has been approved by the National Healthcare Group (NHG) DSRB (DSRB2020/00249). We will report our findings at scientific conferences and/or in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04848935.


Asunto(s)
Inteligencia Artificial , Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/radioterapia , Cognición , Estudios de Factibilidad , Estudios Prospectivos
16.
Theranostics ; 13(2): 621-638, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36632230

RESUMEN

Rationale: Metastasis is a complex process with a molecular underpinning that remains unclear. We hypothesize that cargo proteins conducted by extracellular vesicles (EVs) released from tumors may confer growth and metastasis potential on recipient cells. Here, we report that a cytokine-like secreted protein, FAM3C, contributes to late-stage lung tumor progression. Methods: EV protein profiling was conducted with an unbiased proteomic mass spectrometry analysis on non-small cell lung cancer (NSCLC) and normal lung fibroblast cell lines. Expression of FAM3C was confirmed in a panel of NSCLC cell lines, and correlated to the invasive and metastatic potentials. Functional phenotype of endogenous FAM3C and tumor-derived EVs (TDEs) were further investigated using various biological approaches in RNA and protein levels. Metastasis potential of TDEs secreted by FAM3C-overexpressing carcinoma cells was validated in mouse models. Results: Transcriptomic meta-analysis of pan-cancer datasets confirmed the overexpression of FAM3C - a gene encoding for interleukin-like EMT inducer (ILEI) - in NSCLC tumors, with strong association with poor patient prognosis and cancer metastasis. Aberrant expression of FAM3C in lung carcinoma cells enhances cellular transformation and promotes distant lung tumor colonization. In addition, higher FAM3C concentrations were detected in EVs extracted from plasma samples of NSCLC patients compared to those of healthy subjects. More importantly, we defined a hitherto-unknown mode of microenvironmental crosstalk involving FAM3C in EVs, whereby the delivery and uptake of FAM3C via TDEs enhances oncogenic signaling - in recipient cells that phenocopies the cell-endogenous overexpression of FAM3C. The oncogenicity transduced by FAM3C is executed via a novel interaction with the Ras-related protein RalA, triggering the downstream activation of the Src/Stat3 signaling cascade. Conclusions: Our study describes a novel mechanism for FAM3C-driven carcinogenesis and shed light on EV FAM3C as a driver for metastatic lung tumors that could be exploited for cancer therapeutics.


Asunto(s)
Carcinogénesis , Carcinoma de Pulmón de Células no Pequeñas , Vesículas Extracelulares , Neoplasias Pulmonares , Animales , Humanos , Ratones , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/secundario , Línea Celular Tumoral , Vesículas Extracelulares/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteómica
17.
J Health Psychol ; 27(5): 1111-1124, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33550864

RESUMEN

The Beliefs about Medicines Questionnaire (BMQ) and Adherence Starts with Knowledge (ASK-12) questionnaire were originally developed and validated in Western populations to assess beliefs and barriers to medication adherence. The study aim is to validate the BMQ and ASK-12 questionnaire for use in a Singapore population with early stage breast cancer. English-speaking women on adjuvant endocrine therapy (n = 157) were recruited. The BMQ-Specific showed good internal consistency with structural validity. The internal consistency of BMQ-General and ASK-12 Behaviour scale improved with the new factor structure obtained from exploratory factor analysis. Further studies are needed to confirm these factor structures.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Cumplimiento de la Medicación , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
18.
Front Oncol ; 12: 1048304, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36452498

RESUMEN

Objective: To identify the independent risk factors for 30-day perioperative seizures, as well as to evaluate the effect of perioperative seizures on overall mortality and tumor recurrence among patients who underwent surgical resection of brain metastases. Methods: Patients who underwent surgical resection of brain metastases at our institution between 2011 and 2019 were included. 30-day perioperative seizures were defined as the presence of any preoperative or postoperative seizures diagnosed by a neurosurgeon or neurologist within 30 days of metastases resection. Independent risk factors for 30-day perioperative seizures were evaluated using multivariate logistic regression models. Kaplan-Meier plots and Cox regression models were constructed to evaluate the effects of 30-day perioperative seizures on overall mortality and tumor recurrence. Subgroup analyses were conducted for 30-day preoperative and 30-day postoperative seizures. Results: A total of 158 patients were included in the analysis. The mean (SD) age was 59.3 (12.0) years, and 20 (12.7%) patients had 30-day perioperative seizures. The presence of 30-day preoperative seizures (OR=41.4; 95% CI=4.76, 924; p=0.002) was an independent risk factor for 30-day postoperative seizures. Multivariate Cox regression revealed that any 30-day perioperative seizure (HR=3.25; 95% CI=1.60, 6.62; p=0.001) was independently and significantly associated with overall mortality but not tumor recurrence (HR=1.95; 95% CI=0.78, 4.91; p=0.154). Conclusions: Among patients with resected brain metastases, the presence of any 30-day perioperative seizure was independently associated with overall mortality. This suggests that 30-day perioperative seizures may be a prognostic marker of poor outcome. Further research evaluating this association as well as the effect of perioperative antiepileptic drugs in patients with resected brain metastases may be warranted.

19.
Cancers (Basel) ; 13(2)2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33477629

RESUMEN

Distant organ metastases accounts for the majority of breast cancer deaths. Given the prevalence of breast cancer in women, it is imperative to understand the underlying mechanisms of its metastatic progression and identify potential targets for therapy. Since their discovery in 1993, microRNAs (miRNAs) have emerged as important regulators of tumour progression and metastasis in various cancers, playing either oncogenic or tumour suppressor roles. In the following review, we discuss the roles of miRNAs that potentiate four key areas of breast cancer metastasis-angiogenesis, epithelial-mesenchymal transition, the Warburg effect and the tumour microenvironment. We then evaluate the recent developments in miRNA-based therapies in breast cancer, which have shown substantial promise in controlling tumour progression and metastasis. Yet, certain challenges must be overcome before these strategies can be implemented in clinical trials.

20.
Front Pharmacol ; 12: 828856, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35035355

RESUMEN

Cancer has become a global health problem, accounting for one out of six deaths. Despite the recent advances in cancer therapy, there is still an ever-growing need for readily accessible new therapies. The process of drug discovery and development is arduous and takes many years, and while it is ongoing, the time for the current lead compounds to reach clinical trial phase is very long. Drug repurposing has recently gained significant attention as it expedites the process of discovering new entities for anticancer therapy. One such potential candidate is the antimalarial drug, artemisinin that has shown anticancer activities in vitro and in vivo. In this review, major molecular and cellular mechanisms underlying the anticancer effect of artemisinin and its derivatives are summarised. Furthermore, major mechanisms of action and some key signaling pathways of this group of compounds have been reviewed to explore potential targets that contribute to the proliferation and metastasis of tumor cells. Despite its established profile in malaria treatment, pharmacokinetic properties, anticancer potency, and current formulations that hinder the clinical translation of artemisinin as an anticancer agent, have been discussed. Finally, potential solutions or new strategies are identified to overcome the bottlenecks in repurposing artemisinin-type compounds as anticancer drugs.

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