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1.
Br J Cancer ; 128(4): 665-677, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36522479

RESUMEN

BACKGROUND: Doxorubicin resistance represents a major clinical challenge for treating patients with advanced breast cancer (BC). Exosomes, exchanging genetic cargo between heterogeneous populations of tumour cells, have been proposed to mediate drug resistance and cancer progression in other cancer types. However, their specific role in mediating doxorubicin resistance in BC remains unclear. Here, we demonstrate the important role of exosomal miR-181b-5p (exo-miR-181b-5p) in mediating doxorubicin resistance. METHODS: Small-RNA sequencing and bioinformatic analyses were used to screen miRNAs mediating doxorubicin resistance in BC, which were further verified by RT-qPCR. SA-ß-gal staining assays allowed us to measure cellular senescence. Exosomes from patients' serum before and after neoadjuvant chemotherapy were isolated for exo-miR-181b-5p quantification. RESULTS: Doxorubicin-resistant BC cell lines exhibited upregulated exosomal miR-181b-5p. Addition of exo-miR-181b-5p actively fused with recipient cells and transferred a drug-resistant phenotype. Overexpression of miR-181b-5p downregulated p53/p21 levels and inhibited doxorubicin-induced G1 arrest and senescence by suppressing BCLAF1 expression in vitro. Further, in vivo experiments showed treatment of exo-miR-181b-5p inhibitors exhibited superior tumour control and reversed the doxorubicin-resistance phenotype, accompanied with increased tumoral BCLAF1. CONCLUSION: Our data suggests exo-miR-181b-5p as a prognostic biomarker and a therapeutic potential for exo-miR-181b-5p inhibitors in the treatment of doxorubicin-resistant BC patients.


Asunto(s)
Exosomas , MicroARNs , Neoplasias , Humanos , MicroARNs/genética , Doxorrubicina/farmacología , Neoplasias/patología , Exosomas/genética , Proteínas Represoras/metabolismo , Proteínas Supresoras de Tumor/metabolismo
2.
Br J Cancer ; 129(12): 1877-1892, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37794178

RESUMEN

Thioredoxin-interacting protein (TXNIP) is commonly considered a master regulator of cellular oxidation, regulating the expression and function of Thioredoxin (Trx). Recent work has identified that TXNIP has a far wider range of additional roles: from regulating glucose and lipid metabolism, to cell cycle arrest and inflammation. Its expression is increased by stressors commonly found in neoplastic cells and the wider tumor microenvironment (TME), and, as such, TXNIP has been extensively studied in cancers. In this review, we evaluate the current literature regarding the regulation and the function of TXNIP, highlighting its emerging role in modulating signaling between different cell types within the TME. We then assess current and future translational opportunities and the associated challenges in this area. An improved understanding of the functions and mechanisms of TXNIP in cancers may enhance its suitability as a therapeutic target.


Asunto(s)
Neoplasias , Tiorredoxinas , Humanos , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Glucosa , Inflamación , Neoplasias/inmunología , Neoplasias/metabolismo , Oxidación-Reducción , Tiorredoxinas/metabolismo , Microambiente Tumoral
3.
Br J Cancer ; 128(2): 245-254, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36352028

RESUMEN

BACKGROUND: Epidermal growth factor receptor (EGFR) is a therapeutic target to which HER2/HER3 activation may contribute resistance. This Phase I/II study examined the toxicity and efficacy of high-dose pulsed AZD8931, an EGFR/HER2/HER3 inhibitor, combined with chemotherapy, in metastatic colorectal cancer (CRC). METHODS: Treatment-naive patients received 4-day pulses of AZD8931 with irinotecan/5-FU (FOLFIRI) in a Phase I/II single-arm trial. Primary endpoint for Phase I was dose limiting toxicity (DLT); for Phase II best overall response. Samples were analysed for pharmacokinetics, EGFR dimers in circulating exosomes and Comet assay quantitating DNA damage. RESULTS: Eighteen patients received FOLFIRI and AZD8931. At 160 mg bd, 1 patient experienced G3 DLT; 160 mg bd was used for cohort expansion. No grade 5 adverse events (AE) reported. Seven (39%) and 1 (6%) patients experienced grade 3 and grade 4 AEs, respectively. Of 12 patients receiving 160 mg bd, best overall response rate was 25%, median PFS and OS were 8.7 and 21.2 months, respectively. A reduction in circulating HER2/3 dimer in the two responding patients after 12 weeks treatment was observed. CONCLUSIONS: The combination of pulsed high-dose AZD8931 with FOLFIRI has acceptable toxicity. Further studies of TKI sequencing may establish a role for pulsed use of such agents rather than continuous exposure. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov number: NCT01862003.


Asunto(s)
Neoplasias Colorrectales , Receptor ErbB-3 , Humanos , Receptor ErbB-3/metabolismo , Transducción de Señal , Quinazolinas/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inducido químicamente , Fluorouracilo , Leucovorina/efectos adversos , Camptotecina , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo
4.
Mod Pathol ; 36(12): 100348, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37820765

RESUMEN

p53 immunohistochemistry (IHC) has recently been shown to be a clinically useful marker for predicting risk of progression to invasive squamous cell carcinoma in oral epithelial dysplasia (OED). The literature supports the use of p53 IHC as a marker to identify TP53 mutation in in situ and invasive vulvar lesions and as a surrogate marker for high-risk human papillomavirus (HPV) infection, but there is little documentation for similar use in OED. The purpose of this study was to determine whether p53 IHC is a reliable surrogate marker for detecting both TP53 mutation and high-risk HPV infection in OED. We studied 57 cases of OED (11 mild, 18 moderate, and 28 severe), and all were stained for p16 and p53 IHC. High-risk HPV RNA in situ hybridization (ISH) was performed in selected cases (all p16-positive cases and all OED showing abundant apoptotic cells and karyorrhectic cells; N = 27). Targeted next-generation sequencing (NGS) was performed in 33 p16-negative cases and all high-risk HPV RNA ISH-negative cases (N = 36). We identified 21 cases with p53 basal sparing patterns (mid-epithelial and markedly reduced [null-like]), 14 cases with p53 wild-type patterns (scattered basal and patchy basal/parabasal), and 22 cases with p53 abnormal patterns (18 overexpression, 3 null, and 1 novel cytoplasmic pattern). Among cases with p53 basal sparing patterns, 20 were positive for p16 (20/21, 95%), and all were positive for high-risk HPV RNA ISH (21/21, 100%). The 36 sequenced cases had IHC patterns concordant with TP53 mutation status in 92% (33/36) of lesions. This study demonstrates that p53 IHC expression patterns are sensitive and specific for detection of both high-risk HPV infection and TP53 mutation. Coupled with selective p16 IHC testing, this IHC panel can accurately subclassify OED into HPV-associated, p53 wild-type (conventional), and p53 abnormal OED.


Asunto(s)
Virus del Papiloma Humano , Infecciones por Papillomavirus , Humanos , Inmunohistoquímica , Infecciones por Papillomavirus/patología , Proteína p53 Supresora de Tumor/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , ARN , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Papillomaviridae/genética
5.
Mod Pathol ; 36(7): 100153, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36906072

RESUMEN

The diagnosis of oral epithelial dysplasia is based on the degree of architectural and cytologic atypia in the squamous epithelium. The conventional grading system of mild, moderate, and severe dysplasia is considered by many the gold standard in predicting the risk of malignant transformation. Unfortunately, some low-grade lesions, with or without dysplasia, progress to squamous cell carcinoma (SCC) in short periods. As a result, we are proposing a new approach to characterize oral dysplastic lesions that will help identify lesions at high risk for malignant transformation. We included a total of 203 cases of oral epithelial dysplasia, proliferative verrucous leukoplakia, lichenoid, and commonly observed mucosal reactive lesions to evaluate their p53 immunohistochemical (IHC) staining patterns. We identified 4 wild-type patterns, including scattered basal, patchy basal/parabasal, null-like/basal sparing, mid-epithelial/basal sparing, and 3 abnormal p53 patterns, including overexpression basal/parabasal only, overexpression basal/parabasal to diffuse, and null. All cases of lichenoid and reactive lesions exhibited scattered basal or patchy basal/parabasal patterns, whereas human papillomavirus-associated oral epithelial dysplasia demonstrated null-like/basal sparing or mid-epithelial/basal sparing patterns. Of the oral epithelial dysplasia cases, 42.5% (51/120) demonstrated an abnormal p53 IHC pattern. p53 abnormal oral epithelial dysplasia was significantly more likely to progress to invasive SCC when compared to p53 wild-type oral epithelial dysplasia (21.6% vs 0%, P < .0001). Furthermore, p53 abnormal oral epithelial dysplasia was more likely to have dyskeratosis and/or acantholysis (98.0% vs 43.5%, P < .0001). We propose the term p53 abnormal oral epithelial dysplasia to highlight the importance of utilizing p53 IHC stain to recognize lesions that are at high risk of progression to invasive disease, irrespective of the histologic grade, and propose that these lesions should not be graded using the conventional grading system to avoid delayed management.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Boca , Humanos , Proteína p53 Supresora de Tumor , Neoplasias de la Boca/patología , Inmunohistoquímica , Leucoplasia Bucal/patología , Carcinoma de Células Escamosas/patología , Hiperplasia , Transformación Celular Neoplásica/patología
6.
FASEB J ; 36(11): e22626, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36305462

RESUMEN

PTEN (phosphatase and tensin homolog deleted on chromosome 10) is one of the most frequently mutated/deleted tumor suppressor genes in many human cancers. Ursolic acid (UA) is a natural triterpenoid possessing antioxidant, anti-inflammatory, and anticancer effects. However, how PTEN impacts metabolic rewiring and how UA modifies PTEN-driven metabolic and epigenetic reprogramming in prostate cancer (PCa) remains unknown. In the current study, we found that UA protects against PTEN knockout (KO)-induced tumorigenesis at different stages of PCa. Epigenomic CpG methyl-seq revealed UA attenuated PTEN KO-induced differentially methylated regions (DMRs) profiles. Transcriptomic RNA-seq showed UA abrogated PTEN KO-induced differentially expressed genes (DEGs) of PCa-related oncogenes' Has3, Cfh, and Msx1 overexpression, indicating UA plays a crucial role in PTEN KO-mediated gene regulation and its potential consequences on cancer interception. Association analysis of DEGs and DMRs identified that the mRNA expression of tumor suppressor gene BDH2, and oncogenes Ephas, Isg15, and Nos2 were correlated with the promoter CpG methylation status in the early-stage comparison groups indicating UA could regulate the oncogenes or tumor suppressor genes by modulating their promoter methylation at an early stage of prostate tumorigenesis. The metabolomic study showed UA attenuated PTEN KO-regulated cancer-associated metabolisms like purine metabolism/metabolites correlating with RNAseq findings, glycolysis/gluconeogenesis metabolism, as well as epigenetic-related metabolites pyruvate and lactate indicating UA plays a critical role in PTEN KO-mediated metabolic and epigenetic reprogramming and its consequences on cancer development. In this context, UA impacts metabolic rewiring causing epigenetic and transcriptomic reprogramming potentially contributing to the overall protection against prostate-specific PTEN KO-mediated PCa.


Asunto(s)
Neoplasias de la Próstata , Triterpenos , Masculino , Carcinogénesis/genética , Transformación Celular Neoplásica/genética , Quimioprevención , Epigénesis Genética , Epigenómica , Hidroxibutirato Deshidrogenasa/genética , Hidroxibutirato Deshidrogenasa/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/prevención & control , Neoplasias de la Próstata/patología , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Triterpenos/farmacología , Ratones Noqueados , Ácido Ursólico
7.
Pharm Res ; 40(11): 2699-2714, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37726406

RESUMEN

Since ancient times, dietary phytochemicals are known for their medicinal properties. They are broadly classified into polyphenols, terpenoids, alkaloids, phytosterols, and organosulfur compounds. Currently, there is considerable interest in their potential health effects against various diseases, including lung cancer. Lung cancer is the leading cause of cancer deaths with an average of five-year survival rate of lung cancer patients limited to just 14%. Identifying potential early molecular biomarkers of pre-malignant lung cancer cells may provide a strong basis to develop early cancer detection and interception methods. In this review, we will discuss molecular changes, including genetic alterations, inflammation, signal transduction pathways, redox imbalance, epigenetic and proteomic signatures associated with initiation and progression of lung carcinoma. We will also highlight molecular targets of phytochemicals during lung cancer development. These targets mainly consist of cellular signaling pathways, epigenetic regulators and metabolic reprogramming. With growing interest in natural products research, translation of these compounds into new cancer prevention approaches to medical care will be urgently needed. In this context, we will also discuss the overall pharmacokinetic challenges of phytochemicals in translating to humans. Lastly, we will discuss clinical trials of phytochemicals in lung cancer patients.


Asunto(s)
Anticarcinógenos , Neoplasias Pulmonares , Neoplasias , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/patología , Anticarcinógenos/uso terapéutico , Dieta , Proteómica , Neoplasias/tratamiento farmacológico , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Biomarcadores
8.
J Immunol ; 205(2): 425-437, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32513849

RESUMEN

The continuing emergence of viral pathogens and their rapid spread into heavily populated areas around the world underscore the urgency for development of highly effective vaccines to generate protective antiviral Ab responses. Many established and newly emerging viral pathogens, including HIV and Ebola viruses, are most prevalent in regions of the world in which Mycobacterium tuberculosis infection remains endemic and vaccination at birth with M. bovis bacille Calmette-Guérin (BCG) is widely used. We have investigated the potential for using CD4+ T cells arising in response to BCG as a source of help for driving Ab responses against viral vaccines. To test this approach, we designed vaccines comprised of protein immunogens fused to an immunodominant CD4+ T cell epitope of the secreted Ag 85B protein of BCG. Proof-of-concept experiments showed that the presence of BCG-specific Th cells in previously BCG-vaccinated mice had a dose-sparing effect for subsequent vaccination with fusion proteins containing the Ag 85B epitope and consistently induced isotype switching to the IgG2c subclass. Studies using an Ebola virus glycoprotein fused to the Ag 85B epitope showed that prior BCG vaccination promoted high-affinity IgG1 responses that neutralized viral infection. The design of fusion protein vaccines with the ability to recruit BCG-specific CD4+ Th cells may be a useful and broadly applicable approach to generating improved vaccines against a range of established and newly emergent viral pathogens.


Asunto(s)
Aciltransferasas/inmunología , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Linfocitos T CD4-Positivos/inmunología , Vacunas contra el Virus del Ébola/inmunología , Ebolavirus/fisiología , Fiebre Hemorrágica Ebola/inmunología , Mycobacterium bovis/inmunología , Proteínas del Envoltorio Viral/inmunología , Aciltransferasas/genética , Animales , Anticuerpos Antivirales/metabolismo , Formación de Anticuerpos , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Modelos Animales de Enfermedad , Vacunas contra el Virus del Ébola/genética , Femenino , Humanos , Inmunoglobulina G/sangre , Activación de Linfocitos , Ratones , Ratones Transgénicos , Proteínas Recombinantes de Fusión/genética , Proteínas del Envoltorio Viral/genética
9.
Anesth Analg ; 135(4): 829-836, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35913722

RESUMEN

BACKGROUND: Lumbar erector spinae plane block (ESPB) has been proposed to relieve pain after total hip replacement (THR), but high-quality evidence is scarce. METHODS: This double-blinded (patient and assessor) randomized clinical trial, performed in 2 tertiary centers in Hong Kong, recruited patients undergoing primary unilateral THR under general anesthesia (GA) who received either single-shot ESPB at L1 (treatment arm) or no block (control arm). Patients were followed up on the first day postoperatively. We hypothesized that compared to no block, a single-shot lumbar ESPB at L1 would reduce postoperative fentanyl use and postoperative pain scores. Primary outcomes were intravenous fentanyl use at 12 and 24 hours postoperatively, along with pain intensity in numeric rating scale (0-10) at rest and upon movement on the first day postoperatively. Per-protocol analysis was performed. Mann-Whitney U test was used to compare the outcomes between both groups, and median difference was derived from the Hodges-Lehmann estimator. RESULTS: Seventy-one patients were randomized (n = 36 in treatment arm, n = 35 in control arm). The median amount of fentanyl consumed at 12 hours postoperatively was 210 (quartiles, 140.5-363) µg for the ESPB group and 165 (quartiles, 77.5-330.5) µg for the control group, while at 24 hours postoperatively, it was 409 (quartiles, 221-636.5) µg for the former and 349 (quartiles, 114-626.5) µg for the latter. The median differences in fentanyl consumption 12 and 24 hours postoperatively were 39 µg (95% confidence interval [CI], -40 to 116; P = .463) and 41 µg, respectively (95% CI, -83.5 to 199.5; P = .474), which were statistically insignificant. The median pain score at rest was 3 for both the ESPB group (quartiles, 0-5) and the control group (quartiles, 0-4.5), while upon movement, it was 7 for both the former (quartiles, 6-8) and the latter (quartiles, 4.5-8.5). The median difference in pain scores between both groups was 0 at rest (95% CI, -1 to 1; P = .890) and upon movement (95% CI, -1 to 1; P = .509). CONCLUSIONS: This trial did not demonstrate that ESPB at L1 improved analgesia following THR.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Bloqueo Nervioso , Artroplastia de Reemplazo de Cadera/efectos adversos , Fentanilo/uso terapéutico , Humanos , Bloqueo Nervioso/efectos adversos , Bloqueo Nervioso/métodos , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control , Músculos Paraespinales
10.
BMC Psychiatry ; 22(1): 344, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35585520

RESUMEN

BACKGROUND: Aggression in psychiatric hospitals has been of interest to researchers. Information on how different stakeholders perceive patient aggression remains equivocal. Even less is known about possible similarities or differences in stakeholders' perceptions of how aggressive behaviour is understood, managed and prevented in psychiatric hospitals. We aimed to explore multiple viewpoints on patient aggression, its possible causes and outcomes, and development ideas for prevention and management. METHODS: A qualitative design was adopted. The data were collected using focus group interviews. A thematic approach was used for interpretation. The data were collected on 15 adult wards in two inpatient psychiatric settings in Hong Kong. Participants were nurses working on the psychiatric inpatient wards, patients admitted to the wards, and informal caregivers visiting inpatient wards (N = 94). RESULTS: Commonalities between all groups were found on how patient aggression is perceived, and why it occurs. Patients and especially nurses described how patient aggression occurred with no clear reason or forewarning and how patients were physically controlled or restricted after aggressive events. Only nurses and patients expressed experiencing physical burden, while all groups considered psychological burden to be a consequence of aggression. All groups proposed that helpful attitudes among nurses, better communication, structural changes, and better self-management skills would prevent patient aggression. Risk assessment was proposed only by nurses and patients, while safety measures were proposed by nurses and informal caregivers only. The use of restrictive interventions to manage aggressive events was proposed by all groups. CONCLUSIONS: Despite the complex diversity of perspectives in different stakeholder groups regarding patient aggression, the findings highlighted that it is possible to achieve some mutual understanding of aggression in psychiatric hospitals and identify areas to be developed. Staffs' attitudes and skills for engagement and communication with patients and informal caregivers should be improved. There is also still room to develop the therapeutic environment and culture toward meaningful activities during the treatment period.


Asunto(s)
Cuidadores , Hospitales Psiquiátricos , Adulto , Agresión/psicología , Actitud del Personal de Salud , Grupos Focales , Humanos , Pacientes Internos
11.
Histopathology ; 78(6): 805-813, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33118176

RESUMEN

AIMS: Uterine sarcomas can be grouped into tumours with pathognomonic genetic fusions such as low-grade endometrial stromal sarcoma (LGESS), high-grade endometrial stromal sarcoma (HGESS), and inflammatory myofibroblastic tumour (IMT), and tumours lacking genetic fusions such as leiomyosarcoma (LMS) and undifferentiated uterine sarcoma (UUS). Members of the latter group frequently harbour TP53 mutations. The aim of this study was to evaluate TP53 mutations by the use of immunohistochemistry in fusion-positive uterine sarcomas. METHODS AND RESULTS: We performed p53 immunohistochemical staining on 124 uterine sarcomas harbouring genetic fusions and 38 fusion-negative LMSs and UUSs. These included 41 HGESSs with YWHAE, BCOR and BCORL1 fusions/rearrangements, 13 IMTs with ALK fusion, 12 sarcomas with NTRK1/3 fusion, three sarcomas with PDGFB fusion, and 55 LGESSs with JAZF1, SUZ12 and PHF1 fusions/rearrangements. All HGESSs, LGESSs, IMTs and sarcomas with PDGFB fusion showed wild-type p53 expression. Among NTRK1/3-positive sarcomas, a TPR-NTRK1-positive sarcoma with nuclear pleomorphism showed mutation-type p53 expression. The remaining 11 NTRK1/3-positive sarcomas showed wild-type p53 expression, except for the subclonal p53 mutation-type staining in a minor pleomorphic focus of an NTRK3-positive sarcoma. Twenty-one of 27 (78%) LMSs and six of nine (67%) UUSs showed mutation-type p53 expression. CONCLUSION: p53 immunohistochemistry may be considered in the initial work-up of a uterine sarcoma, as mutation-type staining would make a fusion-positive sarcoma very unlikely. Mutation-type p53 expression, however, can be seen in a small subset of NTRK1/3-positive sarcomas showing pleomorphic round/ovoid cell histology, which may represent a mechanism of progression in these tumours.


Asunto(s)
Proteínas de Fusión Oncogénica/metabolismo , Sarcoma/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Neoplasias Uterinas/metabolismo , Femenino , Reordenamiento Génico , Humanos , Inmunohistoquímica , Proteínas de Fusión Oncogénica/genética , Sarcoma/genética , Sarcoma/patología , Proteína p53 Supresora de Tumor/genética , Neoplasias Uterinas/genética , Neoplasias Uterinas/patología
12.
Eur J Nucl Med Mol Imaging ; 49(1): 371-384, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33837843

RESUMEN

PURPOSE: This study assesses the potential for vascular-metabolic imaging with FluoroDeoxyGlucose (FDG)-Positron Emission Tomography/Computed Tomography (PET/CT) perfusion to provide markers of prognosis specific to the site and stage of colorectal cancer. METHODS: This prospective observational study comprised of participants with suspected colorectal cancer categorized as either (a) non-metastatic colon cancer (M0colon), (b) non-metastatic rectal cancer (M0rectum), or (c) metastatic colorectal cancer (M+). Combined FDG-PET/CT perfusion imaging was successfully performed in 286 participants (184 males, 102 females, age: 69.60 ± 10 years) deriving vascular and metabolic imaging parameters. Vascular and metabolic imaging parameters alone and in combination were investigated with respect to overall survival. RESULTS: A vascular-metabolic signature that was significantly associated with poorer survival was identified for each patient group: M0colon - high Total Lesion Glycolysis (TLG) with increased Permeability Surface Area Product/Blood Flow (PS/BF), Hazard Ratio (HR) 3.472 (95% CI: 1.441-8.333), p = 0.006; M0rectum - high Metabolic Tumour Volume (MTV) with increased PS/BF, HR 4.567 (95% CI: 1.901-10.970), p = 0.001; M+ participants, high MTV with longer Time To Peak (TTP) enhancement, HR 2.421 (95% CI: 1.162-5.045), p = 0.018. In participants with stage 2 colon cancer as well as those with stage 3 rectal cancer, the vascular-metabolic signature could stratify the prognosis of these participants. CONCLUSION: Vascular and metabolic imaging using FDG-PET/CT can be used to synergise prognostic markers. The hazard ratios suggest that the technique may have clinical utility.


Asunto(s)
Neoplasias Colorrectales , Fluorodesoxiglucosa F18 , Anciano , Neoplasias Colorrectales/diagnóstico por imagen , Femenino , Glucólisis , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones , Pronóstico , Radiofármacos , Estudios Retrospectivos , Carga Tumoral
13.
Biochem J ; 477(17): 3329-3347, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32815546

RESUMEN

Despite being catalytically defective, pseudokinases are typically essential players of cellular signalling, acting as allosteric regulators of their active counterparts. Deregulation of a growing number of pseudokinases has been linked to human diseases, making pseudokinases therapeutic targets of interest. Pseudokinases can be dynamic, adopting specific conformations critical for their allosteric function. Interfering with their allosteric role, with small molecules that would lock pseudokinases in a conformation preventing their productive partner interactions, is an attractive therapeutic strategy to explore. As a well-known allosteric activator of epidermal growth factor receptor family members, and playing a major part in cancer progression, the pseudokinase HER3 is a relevant context in which to address the potential of pseudokinases as drug targets for the development of allosteric inhibitors. In this proof-of-concept study, we developed a multiplex, medium-throughput thermal shift assay screening strategy to assess over 100 000 compounds and identify selective small molecule inhibitors that would trap HER3 in a conformation which is unfavourable for the formation of an active HER2-HER3 heterodimer. As a proof-of-concept compound, AC3573 bound with some specificity to HER3 and abrogated HER2-HER3 complex formation and downstream signalling in cells. Our study highlights the opportunity to identify new molecular mechanisms of action interfering with the biological function of pseudokinases.


Asunto(s)
Inhibidores de Proteínas Quinasas , Receptor ErbB-3 , Regulación Alostérica , Animales , Células CHO , Cricetulus , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Prueba de Estudio Conceptual , Unión Proteica , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Receptor ErbB-2/química , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-3/antagonistas & inhibidores , Receptor ErbB-3/química , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo
14.
Skeletal Radiol ; 50(7): 1467-1472, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33447894

RESUMEN

Amyloidosis may be hereditary or acquired and the deposits can be focal, localized, or systemic in distribution. A discrete mass of amyloid deposition is called an amyloidoma and is the least common presentation. Soft tissue amyloidoma in an extremity is exceedingly rare. Amyloidomas can mimic malignant neoplasms both clinically and radiologically. We report a case of an amyloidoma in the foot, which has not been previously described. Clinical history, pathology, and immunohistochemistry and appearance by MRI are described. Knowledge of this atypical lesion, in its various forms, is important for experts in musculoskeletal radiology, pathology, surgery, and oncology to appreciate as it can prevent confusion with more sinister disease processes such as malignancy. Early recognition can help guide appropriate management in a timely fashion.


Asunto(s)
Amiloidosis , Neoplasias de los Tejidos Blandos , Amiloidosis/diagnóstico por imagen , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Neoplasias de los Tejidos Blandos/diagnóstico por imagen
15.
Infect Immun ; 88(12)2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-32989037

RESUMEN

The interaction of host cells with mycobacteria is complex and can lead to multiple outcomes ranging from bacterial clearance to progressive or latent infection. Autophagy is recognized as one component of host cell responses that has an essential role in innate and adaptive immunity to intracellular bacteria. Many microbes, including Mycobacterium tuberculosis, have evolved to evade or exploit autophagy, but the precise mechanisms and virulence factors are mostly unknown. Through a loss-of-function screening of an M. tuberculosis transposon mutant library, we identified 16 genes that contribute to autophagy inhibition, six of which encoded the PE/PPE protein family. Their expression in Mycobacterium smegmatis confirmed that these PE/PPE proteins inhibit autophagy and increase intracellular bacterial persistence or replication in infected cells. These effects were associated with increased mammalian target of rapamycin (mTOR) activity and also with decreased production of tumor necrosis factor alpha (TNF-α) and interleukin-1ß (IL-1ß). We also confirmed that the targeted deletion of the pe/ppe genes in M. tuberculosis resulted in enhanced autophagy and improved intracellular survival rates compared to those of wild-type bacteria in the infected macrophages. Differential expression of these PE/PPE proteins was observed in response to various stress conditions, suggesting that they may confer advantages to M. tuberculosis by modulating its interactions with host cells under various conditions. Our findings demonstrated that multiple M. tuberculosis PE/PPE proteins are involved in inhibiting autophagy during infection of host phagocytes and may provide strategic targets in developing therapeutics or vaccines against tuberculosis.


Asunto(s)
Autofagia , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana/genética , Interacciones Microbiota-Huesped/inmunología , Macrófagos/metabolismo , Mycobacterium tuberculosis/genética , Tuberculosis/metabolismo , Animales , Proteínas Bacterianas/metabolismo , Biblioteca de Genes , Ensayos Analíticos de Alto Rendimiento , Interacciones Microbiota-Huesped/genética , Inmunidad Innata , Interleucina-1beta/metabolismo , Macrófagos/microbiología , Ratones , Mycobacterium smegmatis/fisiología , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/inmunología , Células RAW 264.7 , Serina-Treonina Quinasas TOR/metabolismo , Tuberculosis/genética , Tuberculosis/microbiología , Factor de Necrosis Tumoral alfa/metabolismo , Factores de Virulencia/genética
16.
Breast Cancer Res Treat ; 183(3): 525-547, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32685993

RESUMEN

PURPOSE: Previous studies indicate that breast cancer molecular subtypes differ with respect to their dependency on autophagy, but our knowledge of the differential expression and prognostic significance of autophagy-related biomarkers in breast cancer is limited. METHODS: Immunohistochemistry (IHC) was performed on tissue microarrays from a large population of 3992 breast cancer patients divided into training and validation cohorts. Consensus staining scores were used to evaluate the expression levels of autophagy proteins LC3B, ATG4B, and GABARAP and determine the associations with clinicopathological variables and molecular biomarkers. Survival analyses were performed using the Kaplan-Meier function and Cox proportional hazards regression models. RESULTS: We found subtype-specific expression differences for ATG4B, with its expression lowest in basal-like breast cancer and highest in Luminal A, but there were no significant associations with patient prognosis. LC3B and GABARAP levels were highest in basal-like breast cancers, and high levels were associated with worse outcomes across all subtypes (DSS; GABARAP: HR 1.43, LC3B puncta: HR 1.43). High ATG4B levels were associated with ER, PR, and BCL2 positivity, while high LC3B and GABARAP levels were associated with ER, PR, and BCL2 negativity, as well as EGFR, HER2, HER3, CA-IX, PD-L1 positivity, and high Ki67 index (p < 0.05 for all associations). Exploratory multi-marker analysis indicated that the combination of ATG4B and GABARAP with LC3B could be useful for further stratifying patient outcomes. CONCLUSIONS: ATG4B levels varied across breast cancer subtypes but did not show prognostic significance. High LC3B expression and high GABARAP expression were both associated with poor prognosis and with clinicopathological characteristics of aggressive disease phenotypes in all breast cancer subtypes.


Asunto(s)
Neoplasias de la Mama , Proteínas Reguladoras de la Apoptosis , Autofagia , Proteínas Relacionadas con la Autofagia/genética , Biomarcadores de Tumor , Neoplasias de la Mama/genética , Cisteína Endopeptidasas , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Proteínas Asociadas a Microtúbulos/genética , Pronóstico
17.
Br J Clin Pharmacol ; 86(9): 1726-1735, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32388875

RESUMEN

Radiation therapy is an essential component of cancer care, contributing up to 40% of curative cancer treatment regimens. It creates DNA double-strand breaks causing cell death in highly replicating tumour cells. However, tumours can develop acquired resistance to therapy. The efficiency of radiation treatment has been increased by means of combining it with other approaches such as chemotherapy, molecule-targeted therapies and, in recent years, immunotherapy (IT). Cancer-cell apoptosis after radiation treatment causes an immunological reaction that contributes to eradicating the tumour via antigen presentation and subsequent T-cell activation. By contrast, radiotherapy also contributes to the formation of an immunosuppressive environment that hinders the efficacy of the therapy. Innate immune cells from myeloid and lymphoid origin show a very active role in both acquired resistance and antitumourigenic mechanisms. Therefore, many efforts are being made in order to reach a better understanding of the innate immunity reactions after radiation therapy (RT) and the design of new combinatorial IT strategies focused in these particular populations.


Asunto(s)
Neoplasias , Microambiente Tumoral , Humanos , Inmunidad Innata , Inmunoterapia , Terapia Molecular Dirigida , Neoplasias/radioterapia
18.
J Immunol ; 201(12): 3604-3616, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30455402

RESUMEN

Effective subunit vaccines require the incorporation of adjuvants that stimulate cells of the innate immune system to generate protective adaptive immune responses. Pattern recognition receptor agonists are a growing class of potential adjuvants that can shape the character of the immune response to subunit vaccines by directing the polarization of CD4 T cell differentiation to various functional subsets. In the current study, we applied a high-throughput in vitro screen to assess murine CD4 T cell polarization by a panel of pattern recognition receptor agonists. This identified lipopeptides with TLR2 agonist activity as exceptional Th1-polarizing adjuvants. In vivo, we demonstrated that i.v. administration of TLR2 agonists with Ag in mice replicated the findings from in vitro screening by promoting strong Th1 polarization. In contrast, TLR2 agonists inhibited priming of Th1 responses when administered cutaneously in mice. This route-specific suppression was associated with infiltrating CCR2+ cells in the skin-draining lymph nodes and was not uniquely dependent on any of the well characterized subsets of dendritic cells known to reside in the skin. We further demonstrated that priming of CD4 T cells to generate Th1 effectors following immunization with the Mycobacterium bovis bacillus Calmette-Guérin (BCG) strain, a lipoprotein-rich bacterium recognized by TLR2, was dependent on the immunization route, with significantly greater Th1 responses with i.v. compared with intradermal administration of BCG. A more complete understanding of route-dependent TLR2 responses may be critical for informed design of novel subunit vaccines and for improvement of BCG and other vaccines based on live-attenuated organisms.


Asunto(s)
Monocitos/inmunología , Mycobacterium bovis/inmunología , Receptores CCR2/metabolismo , Piel/inmunología , Células TH1/inmunología , Receptor Toll-Like 2/metabolismo , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Movimiento Celular , Células Cultivadas , Vías de Administración de Medicamentos , Femenino , Tolerancia Inmunológica , Inmunización , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Receptores CCR2/genética , Proteínas Represoras/genética , Vacunación
19.
Pediatr Dev Pathol ; 23(2): 132-138, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31403913

RESUMEN

Malignant rhabdoid tumors and atypical teratoid/rhabdoid tumors of the central nervous system are primitive malignancies associated with a poor prognosis. These tumors have previously been characterized by inactivation of the switch/sucrose nonfermenting (SWI/SNF) chromatin remodeling complex protein integrase interactor 1 (INI1), encoded by the SMARCB1 gene. In the last decade, sporadic publications have shown that a different SWI/SNF protein, brahma-related gene 1 (BRG1), encoded by the SMARCA4 gene, is associated with a similar rhabdoid phenotype and possible germline mutation termed rhabdoid tumor predisposition syndrome type 2. We sought to determine the presence of BRG1 expression in pediatric embryonal tumors. Using a local tissue microarray consisting of 28 tumors diagnosed as having an undifferentiated, polyphenotypic, or rhabdoid morphology, expression of BRG1 by immunohistochemistry was performed. Four cases showed loss of INI1, while 3 of the remaining 24 cases demonstrated loss of BRG1. Two cases were diagnosed as soft tissue sarcomas, and 1 case was diagnosed as a small cell carcinoma of the ovary, hypercalcemic type. Survival ranged from less than 6 months after diagnosis to more than 5 years at the time of last follow-up. In conclusion, we demonstrate that BRG1 immunohistochemistry is a useful second-line immunostain for the workup of undifferentiated, polyphenotypic or rhabdoid pediatric tumors that demonstrate retained expression of INI1.


Asunto(s)
ADN Helicasas/metabolismo , Proteínas Nucleares/metabolismo , Tumor Rabdoide/metabolismo , Proteína SMARCB1/metabolismo , Factores de Transcripción/metabolismo , Adolescente , Niño , Preescolar , Estudios de Cohortes , ADN Helicasas/genética , Femenino , Humanos , Inmunohistoquímica , Lactante , Recién Nacido , Masculino , Proteínas Nucleares/genética , Pediatría , Fenotipo , Tumor Rabdoide/diagnóstico , Tumor Rabdoide/patología , Proteína SMARCB1/genética , Factores de Transcripción/genética
20.
Anesth Analg ; 130(2): 498-504, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-30985383

RESUMEN

BACKGROUND: Hip fracture is a challenging geriatric problem for the health care professionals, especially in patients with multiple comorbidities. In patients with inoperable hip fracture secondary to severe comorbid conditions, the pain can lead to significant challenges in nursing care. With the current understanding of the innervation of hip joint, we are now able to perform selective chemical denervation of the articular branches of femoral and obturator nerves to manage the pain associated with inoperable hip fracture. METHODS: In this retrospective case series, we analyzed 20 consecutive patients with inoperable hip fracture who received chemical denervation and examined the effect of the denervation on pain and functional outcomes, including the maximally tolerable hip flexion and the ability to sit during their hospital stay. We also assessed the likelihood of being ambulatory as a long-term outcome. RESULTS: The movement-related pain was significantly reduced at 10 minutes postprocedure, on postintervention days 1 and 5 (P values of <.001), and the degree of maximally tolerable hip flexion was doubled at the same time points (P values of <.001, .003, and .002, respectively). Fifty percent of the patients managed to sit within the first 5 days after procedure, and 3 of them managed to walk with aid 4 months after hip denervation. No procedural adverse event was noted. CONCLUSIONS: We concluded that this chemical hip denervation could be a safe and effective measure to handle the pain-related and rehabilitation-related challenges as a result of inoperable hip fracture.


Asunto(s)
Etanol/administración & dosificación , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/tratamiento farmacológico , Bloqueo Nervioso/métodos , Manejo del Dolor/métodos , Anciano , Anciano de 80 o más Años , Desnervación/métodos , Femenino , Nervio Femoral/diagnóstico por imagen , Nervio Femoral/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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