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1.
Front Pediatr ; 11: 1214551, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520056

RESUMO

Background: Systemic lupus erythematosus (SLE) can involve any organ system and cause a wide range of manifestations. Noninfectious inflammatory lesions termed aseptic abscesses have been reported in some autoimmune and autoinflammatory conditions but not in childhood-onset SLE. In this report, we highlight the unusual finding of occult splenic abscesses in two children diagnosed with SLE who had no evidence of concomitant infection. Case presentation: An 8-year-old and an 11-year-old were admitted separately to the hospital with fever for 7 and 14 days, respectively. In the younger child, a generalized rash preceded the fever. Both had been well, with no significant past medical history prior to the onset of the illness. In both girls, abdominal ultrasonography showed multiple small hypoechoic lesions suggestive of abscesses scattered throughout the spleen. Their C-reactive protein and blood cultures were negative, and symptoms persisted despite intravenous antibiotics. Fulfilling the clinical and immunologic criteria for diagnosis, both were ultimately diagnosed with childhood-onset SLE. Rapid recovery of symptoms and complete resolution of the abscesses ensued with corticosteroids and immunosuppressive therapy. Conclusions: These two cases suggest that aseptic splenic abscesses may occur in childhood-onset SLE. Autoimmune conditions such as SLE should be included in the differential diagnosis of children with occult splenic abscesses.

2.
J Biosci Bioeng ; 136(3): 223-231, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37344279

RESUMO

Little is currently known about the metabolism of the industrial pollutant 2,4-dinitrophenol (DNP), particularly among gram-negative bacteria. In this study, we identified two non-contiguous genetic loci spanning 22 kb of Paraburkholderia (formerly Burkholderia) sp. strain KU-46. Additionally, we characterized four key initial genes (dnpA, dnpB, and dnpC1C2) responsible for DNP degradation, providing molecular and biochemical evidence for the degradation of DNP via the formation of 4-nitrophenol (NP), a pathway that is unique among DNP utilizing bacteria. Reverse transcription polymerase chain reaction (PCR) analysis indicated that dnpA, which encodes the initial hydride transferase, and dnpB which encodes a nitrite-eliminating enzyme, were induced by DNP and organized in an operon. Moreover, we purified DnpA and DnpB from recombinant Escherichia coli to demonstrate their effect on the transformation of DNP to NP through the formation of a hydride-Meisenheimer complex of DNP, designated as H--DNP. The function of DnpB appears new since all homologs of the DnpB sequences in the protein database are annotated as putative nitrate ABC transporter substrate-binding proteins. The gene cluster responsible for the degradation of DNP after NP formation was designated dnpC1C2DXFER, and DnpC1 and DnpC2 were functionally characterized as the FAD reductase and oxygenase components of the two-component DNP monooxygenase, respectively. By elucidating the hqdA1A2BCD gene cluster, we are now able to delineate the final degradation pathway of hydroquinone to ß-ketoadipate before it enters the tricarboxylic acid cycle.


Assuntos
2,4-Dinitrofenol , Oxigenases de Função Mista , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , 2,4-Dinitrofenol/metabolismo , Oxigenases/genética , Oxigenases/metabolismo , Clonagem Molecular , Família Multigênica , Biodegradação Ambiental
3.
J Vasc Surg Cases Innov Tech ; 9(2): 101035, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37013065

RESUMO

A 67-year-old woman with endometrial adenocarcinoma had sustained an aortic injury during robotically assisted retroperitoneal lymphadenectomy. Repair could not be performed laparoscopically; however, graspers were used to maintain hemostasis while conversion to open surgery was initiated. Safety mechanisms locked the graspers in place, preventing tissue release, but resulting in additional aortic injury. Forceful removal of the graspers was eventually successful, and definitive aortic repair was then performed. Vascular surgeons who are not familiar with robotic surgery techniques should be aware that removal of robotic hardware requires the use of stepwise algorithms, which, if performed out of order, can introduce significant challenges.

4.
Front Immunol ; 13: 1048758, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466880

RESUMO

Tissue-resident memory T (TRM) cells have emerged as key players in the immune control of melanoma. These specialized cells are identified by expression of tissue retention markers such as CD69, CD103 and CD49a with downregulation of egress molecules such as Sphingosine-1-Phosphate Receptor-1 (S1PR1) and the lymphoid homing receptor, CD62L. TRM have been shown to be integral in controlling infections such as herpes simplex virus (HSV), lymphocytic choriomeningitis virus (LCMV) and influenza. More recently, robust pre-clinical models have also demonstrated TRM are able to maintain melanoma in a dormant state without progression to macroscopic disease reminiscent of their ability to control viral infections. The discovery of the role these cells play in anti-melanoma immunity has coincided with the advent of immune checkpoint inhibitor (ICI) therapy which has revolutionized the treatment of cancers. ICIs that target programmed death protein-1 (PD-1) and cytotoxic T lymphocyte antigen-4 (CTLA-4) have led to substantial improvements in outcomes for patients with metastatic melanoma and have been rapidly employed to reduce recurrences in the resected stage III setting. While ICIs mediate anti-tumor activity via CD8+ T cells, the specific subsets that facilitate this response is unclear. TRM invariably exhibit high expression of immune checkpoints such as PD-1, CTLA-4 and lymphocyte activating gene-3 (LAG-3) which strongly implicates this CD8+ T cell subset as a crucial mediator of ICI activity. In this review, we present pre-clinical and translational studies that highlight the critical role of TRM in both immune control of primary melanoma and as a key CD8+ T cell subset that mediates anti-tumor activity of ICIs for the treatment of melanoma.


Assuntos
Melanoma , Células T de Memória , Humanos , Antígeno CTLA-4 , Linfócitos T CD8-Positivos , Receptor de Morte Celular Programada 1 , Melanoma/terapia
5.
J Clin Neurosci ; 102: 65-70, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35728397

RESUMO

Medulloblastoma in adult patients is a rare condition with limited contemporary demographic and treatment outcome data available in an Australian population. We conducted a retrospective review of patterns of care and outcomes of adult patients diagnosed with medulloblastoma treated at major neuro-oncology centres across Australia between January 2010 and December 2019. A total of 80 patients were identified and the median follow-up after diagnosis was 59.2 (range 0.5-204) months. A variety of chemotherapy regimens were used in the adjuvant and recurrent settings. The median overall survival (mOS) was 78 months (IQR 17.5-94.8). Patients who had no residual disease post-resection or with SHH-subtype tumours had a numerically longer 5-year survival rate than those with residual disease post resection or non-SHH subtypes respectively. The median time to recurrence from diagnosis was 18.4 months. The median OS from 1st relapse was 22.1 months (95% CI 11.7-31.4) and mOS from second relapse was 10.2 months (95% CI 6.6 - NR). This is the largest dataset examining patterns of care of adult patients with medulloblastoma in an Australian population. Substantial variation existed in the chemotherapy agents used in the adjuvant and recurrent setting. As has been demonstrated in a paediatric population, trials such as the upcoming EORTC 1634-BTG/NOA-23 trial (PersoMed-1 study) which are tailoring treatments to molecular profiles are likely to improve outcome in adult medulloblastoma.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , Adulto , Austrália/epidemiologia , Neoplasias Cerebelares/diagnóstico , Neoplasias Cerebelares/epidemiologia , Neoplasias Cerebelares/terapia , Criança , Terapia Combinada , Humanos , Meduloblastoma/tratamento farmacológico , Meduloblastoma/terapia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/terapia , Radioterapia Adjuvante , Estudos Retrospectivos
6.
Nat Commun ; 13(1): 1100, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35232962

RESUMO

Despite the success of therapies targeting oncogenes in cancer, clinical outcomes are limited by residual disease that ultimately results in relapse. This residual disease is often characterized by non-genetic adaptive resistance, that in melanoma is characterised by altered metabolism. Here, we examine how targeted therapy reprograms metabolism in BRAF-mutant melanoma cells using a genome-wide RNA interference (RNAi) screen and global gene expression profiling. Using this systematic approach we demonstrate post-transcriptional regulation of metabolism following BRAF inhibition, involving selective mRNA transport and translation. As proof of concept we demonstrate the RNA processing kinase U2AF homology motif kinase 1 (UHMK1) associates with mRNAs encoding metabolism proteins and selectively controls their transport and translation during adaptation to BRAF-targeted therapy. UHMK1 inactivation induces cell death by disrupting therapy induced metabolic reprogramming, and importantly, delays resistance to BRAF and MEK combination therapy in multiple in vivo models. We propose selective mRNA processing and translation by UHMK1 constitutes a mechanism of non-genetic resistance to targeted therapy in melanoma by controlling metabolic plasticity induced by therapy.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Terapia de Alvo Molecular , Mutação , Recidiva Local de Neoplasia/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/metabolismo , RNA Mensageiro/uso terapêutico
7.
Appl Environ Microbiol ; 88(1): e0152221, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34705546

RESUMO

The single putative cutinase-encoding gene from the genome of Kineococcus radiotolerans SRS30216 was cloned and expressed in Escherichia coli as a secreted fusion protein, designated YebF-KrCUT, where YebF is the extracellular carrier protein. The 294-amino-acid sequence of KrCUT is unique among currently characterized cutinases by having a C-terminal extension that consists of a short (Pro-Thr)-rich linker and a 55-amino-acid region resembling the substrate binding domain of poly(hydroxybutyrate) (PHB) depolymerases. Phylogenetically, KrCUT takes a unique position among known cutinases and cutinase-like proteins of bacterial and fungal origins. A modeled structure of KrCUT, although displaying a typical α/ß hydrolase fold, shows some unique loops close to the catalytic site. The 39-kDa YebF-KrCUT fusion protein and a truncated variant thereof were purified to electrophoretic homogeneity and functionally characterized. The melting temperatures (Tm) of KrCUT and its variant KrCUT206 devoid of the putative PHB-binding domain were established to be very similar, at 50 to 51°C. Cutinase activity was confirmed by the appearance of characteristic cutin components, C16 and C18 hydroxyl fatty acids, in the mass chromatograms following incubation of KrCUT with apple cutin as the substrate. KrCUT also efficiently degraded synthetic polyesters such as polycaprolactone and poly(1,3-propylene adipate). Although incapable of PHB depolymerization, KrCUT could efficiently bind PHB, confirming the predicted characteristic of the C-terminal region. KrCUT also potentiated the activity of pectate lyase in the degradation of pectin from hemp fibers. This synergistic effect is relevant to the enzyme retting process of natural fibers. IMPORTANCE To date, only a limited number of cutinases have been isolated and characterized from nature, the majority being sourced from phytopathogenic fungi and thermophilic bacteria. The significance of our research relates to the identification and characterization of a unique member of the microbial cutinases, named KrCUT, that was derived from the genome of the Gram-positive Kineococcus radiotolerans SRS30216, a highly radiation-resistant actinobacterium. Given the wide-ranging importance of cutinases in applications such as the degradation of natural and synthetic polymers, in the textile industry, in laundry detergents, and in biocatalysis (e.g., transesterification reactions), our results could foster new research leading to broader biotechnological impacts. This study also demonstrated that genome mining or prospecting is a viable means to discover novel biocatalysts as environmentally friendly and biotechnological tools.


Assuntos
Hidrolases de Éster Carboxílico , Polímeros , Sequência de Aminoácidos , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Domínio Catalítico , Fungos/metabolismo
8.
Cancers (Basel) ; 13(24)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34944961

RESUMO

Despite the success of immune checkpoint inhibitors that target cytotoxic lymphocyte antigen-4 (CTLA-4) and programmed-cell-death-1 (PD-1) in the treatment of metastatic melanoma, there is still great need to develop robust options for patients who are refractory to first line immunotherapy. As such there has been a resurgence in interest of adoptive cell transfer (ACT) particularly derived from tumor infiltrating lymphocytes. Moreover, the addition of cyclin dependent kinase 4/6 inhibitors (CDK4/6i) have been shown to greatly extend duration of response in combination with BRAF-MEK inhibitors (BRAF-MEKi) in pre-clinical models of melanoma. We therefore investigated whether combinations of BRAF-MEK-CDK4/6i and ACT were efficacious in murine models of melanoma. Triplet targeted therapy of BRAF-MEK-CDK4/6i with OT-1 ACT led to sustained and robust anti-tumor responses in BRAFi sensitive YOVAL1.1. We also show that BRAF-MEKi but not CDK4/6i enhanced MHC Class I expression in melanoma cell lines in vitro. Paradoxically CDK4/6i in low concentrations of IFN-γ reduced expression of MHC Class I and PD-L1 in YOVAL1.1. Overall, this work provides additional pre-clinical evidence to pursue combination of BRAF-MEK-CDK4/6i and to combine this combination with ACT in the clinic.

9.
J Immunother Cancer ; 9(10)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34625515

RESUMO

BACKGROUND: Melanoma brain metastases (MBMs) are a challenging clinical problem with high morbidity and mortality. Although first-line dabrafenib-trametinib and ipilimumab-nivolumab have similar intracranial response rates (50%-55%), central nervous system (CNS) resistance to BRAF-MEK inhibitors (BRAF-MEKi) usually occurs around 6 months, and durable responses are only seen with combination immunotherapy. We sought to investigate the utility of ipilimumab-nivolumab after MBM progression on BRAF-MEKi and identify mechanisms of resistance. METHODS: Patients who received first-line ipilimumab-nivolumab for MBMs or second/third line ipilimumab-nivolumab for intracranial metastases with BRAFV600 mutations with prior progression on BRAF-MEKi and MRI brain staging from March 1, 2015 to June 30, 2018 were included. Modified intracranial RECIST was used to assess response. Formalin-fixed paraffin-embedded samples of BRAFV600 mutant MBMs that were naïve to systemic treatment (n=18) or excised after progression on BRAF-MEKi (n=14) underwent whole transcriptome sequencing. Comparative analyses of MBMs naïve to systemic treatment versus BRAF-MEKi progression were performed. RESULTS: Twenty-five and 30 patients who received first and second/third line ipilimumab-nivolumab, were included respectively. Median sum of MBM diameters was 13 and 20.5 mm for the first and second/third line ipilimumab-nivolumab groups, respectively. Intracranial response rate was 75.0% (12/16), and median progression-free survival (PFS) was 41.6 months for first-line ipilimumab-nivolumab. Efficacy of second/third line ipilimumab-nivolumab after BRAF-MEKi progression was poor with an intracranial response rate of 4.8% (1/21) and median PFS of 1.3 months. Given the poor activity of ipilimumab-nivolumab after BRAF-MEKi MBM progression, we performed whole transcriptome sequencing to identify mechanisms of drug resistance. We identified a set of 178 differentially expressed genes (DEGs) between naïve and MBMs with progression on BRAF-MEKi treatment (p value <0.05, false discovery rate (FDR) <0.1). No distinct pathways were identified from gene set enrichment analyses using Kyoto Encyclopedia of Genes and Genomes, Gene Ontogeny or Hallmark libraries; however, enrichment of DEG from the Innate Anti-PD1 Resistance Signature (IPRES) was identified (p value=0.007, FDR=0.03). CONCLUSIONS: Second-line ipilimumab-nivolumab for MBMs after BRAF-MEKi progression has poor activity. MBMs that are resistant to BRAF-MEKi that also conferred resistance to second-line ipilimumab-nivolumab showed enrichment of the IPRES gene signature.


Assuntos
Neoplasias Encefálicas/etiologia , Ipilimumab/uso terapêutico , Melanoma/complicações , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/genética , Feminino , Humanos , Ipilimumab/farmacologia , Masculino , Melanoma/genética , Pessoa de Meia-Idade , Nivolumabe/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Adulto Jovem
10.
BMC Infect Dis ; 21(1): 1069, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654392

RESUMO

BACKGROUND: Melioidosis, the infection caused by Burkholderia pseudomallei, is associated with a high case fatality rate, due in part to difficulties in clinical recognition and diagnostic confirmation of the disease. Although head and neck involvement is common in children, specific disease manifestations differ between geographic regions. The aim of this study was to provide a detailed description of melioidosis of the head and neck among children in Sarawak, Malaysia, and determine if fine-needle aspiration of suspected head or neck lesions could improve melioidosis diagnosis. METHODS: We conducted a retrospective descriptive study of all children aged < 12 years with culture-confirmed melioidosis presenting with head and neck manifestations and admitted to Bintulu Hospital in Sarawak, Malaysia, from January 2011 until December 2020. Fine-needle aspiration of head and neck lesions suspected to be due to melioidosis with inoculation in blood culture bottles (FNA + BCB) was used from the beginning of 2016. RESULTS: Of 34 children with culture-confirmed melioidosis, 20 (59%) had an infection involving one or more sites in the head and neck. Of these, 17 (85%) were diagnosed in or after 2016. Cervical lymph nodes were the most common organ or site affected, involved in 19 (95%) children. Clinical presentations of B. pseudomallei lymph node infections were highly variable. Five (25%) children had salivary gland involvement. Lacrimal gland involvement (dacryocystitis) and skin or soft tissue infection (scalp abscess) were less frequent. B. pseudomallei was isolated from the head or neck using FNA + BCB in 15 (75%) children and by standard culture methods of direct plating of pus on agar following incision and drainage in only 2 (10%) children. B. pseudomallei was isolated from non-head or neck specimens or blood in 3 (15%) children. CONCLUSIONS: Manifestations of pediatric head and neck melioidosis in Sarawak, Malaysia, differ from those of other regions. Fine-needle aspiration, mainly of affected cervical lymph nodes, facilitates B. pseudomallei detection and enables confirmation of melioidosis infections.


Assuntos
Burkholderia pseudomallei , Melioidose , Biópsia por Agulha Fina , Criança , Humanos , Malásia/epidemiologia , Melioidose/diagnóstico , Melioidose/epidemiologia , Estudos Retrospectivos
11.
J Biosci Bioeng ; 132(6): 621-629, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34583900

RESUMO

Cyclohexanecarboxylate (CHCA) is formed by oxidative microbial degradation of n-alkylcycloparaffins and anaerobic degradation of benzoate, and also known to be a synthetic intermediate or the starter unit of biosynthesis of cellular constituents and secondary metabolites. Although two degradation pathways have been proposed, genetic information has been limited to the ß-oxidation-like pathway. In this study, we identified a gene cluster, designated chcC1XTC2B1B2RAaAbAc, that is responsible for the CHCA aromatization pathway in Sinomonas (formerly Corynebacterium) cyclohexanicum strain ATCC 51369. Reverse transcription-PCR analysis indicated that the chc gene cluster is inducible by CHCA and that it consists of two transcriptional units, chcC1XTC2B1B2R and chcAaAbAc. Overexpression of the various genes in Escherichia coli, and purification of the recombinant proteins led to the functional characterization of ChcAaAbAc as subunits of a cytochrome P450 system responsible for CHCA hydroxylation; ChcB1 and ChcB2 as trans-4-hydroxyCHCA and cis-4-hydroxyCHCA dehydrogenases, respectively; ChcC1 was identified as a 4-oxoCHCA desaturase containing a covalently bound FAD; and ChcC2 was identified as a 4-oxocyclohexenecarboxylate desaturase. The binding constant of ChcAa for CHCA was found to be 0.37 mM. Kinetic parameters established for ChcB1 indicated that it has a high catalytic efficiency towards 4-oxoCHCA compared to trans- or cis-4-hydroxyCHCA. The Km and Kcat values of ChcC1 for 4-oxoCHCA were 0.39 mM and 44 s-1, respectively. Taken together with previous work on the identification of a pobA gene encoding a 4-hydroxybenzoate hydroxylase, we have now localized the remaining set of genes for the final degradation of protocatechuate before entry into the tricarboxylic acid cycle.


Assuntos
Proteínas de Escherichia coli , Genes Bacterianos , Proteínas da Membrana Bacteriana Externa , Sequência de Bases , Benzoatos , Escherichia coli/genética , Família Multigênica
12.
Eur J Cancer ; 156: 149-163, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34454317

RESUMO

BACKGROUND: Melanoma brain metastases (MBM) have a poor prognosis. Systemic treatments that have improved outcomes in advanced melanoma have been shown to have an intracranial (IC) effect. We studied the efficacy and outcomes of combined immune checkpoint inhibitor ipilimumab/nivolumab (Combi-ICI) or targeted therapy (Combi-TT) as first-line treatment in MBM. METHODS: MBM patients treated with Combi-ICI or Combi-TT within 3 months after MBM diagnosis. Endpoints were progression-free survival (PFS) and overall survival (OS). RESULTS: 53 patients received Combi-ICI, 32% had symptomatic MBM and 33.9% elevated LDH. 71.7% required local treatment. The disease control rate was 60.3%. IC response rate (RR) was 43.8% at 3-months with durable responses at 6- (46.5%) and 12-months (53.1%). Extracranial (EC) RR was 44.7% at 3-months and 50% at 12-months. Median PFS was 9.6 months (95% CI 3.6-NR) and median overall survival (mOS) 44.8 months (95% CI; 26.2-NR). 63 patients received Combi-TT, 55.6% of patients had symptomatic MBM, 57.2% of patients had elevated LDH and 68.3% of patients required local treatment. The disease control rate was 60.4%. ICRR was 50% at 3-months, but dropped at 6-months (20.9%). ECRR was 69.2% at 3-months and 17.6% at 12-months. Median PFS was 5.8 months (95% CI 4.2-7.6) and mOS 14.2 months (95% CI 8.99-26.8). In BRAFV600 patients, 26.7% of patients received Combi-ICI and 73.3% Combi-TT with OS (p = 0.0053) and mPFS (p = 0.03) in favour to Combi-ICI. CONCLUSION: Combi-ICI showed prolonged mOS with sustainable IC and EC responses. Despite the initially increased efficacy, Combi-TT responses at 12 months were low. Combi-ICI appeared superior to Combi-TT for OS and PFS in BRAFV600 patients. Other clinical factors are determinants for first-line treatment choice.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/secundário , Antígeno CTLA-4/antagonistas & inibidores , Europa (Continente) , Feminino , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , MAP Quinase Quinase Quinases/antagonistas & inibidores , Masculino , Melanoma/enzimologia , Melanoma/imunologia , Melanoma/secundário , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Estudos Retrospectivos , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Fatores de Tempo , Vitória , Adulto Jovem
13.
J Biomed Sci ; 28(1): 54, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34281540

RESUMO

BACKGROUND: Current multiparametric MRI (mp-MRI) in routine clinical practice has poor-to-moderate diagnostic performance for transition zone prostate cancer. The aim of this study was to evaluate the potential diagnostic performance of novel 1H magnetic resonance spectroscopic imaging (MRSI) using a semi-localized adiabatic selective refocusing (sLASER) sequence with gradient offset independent adiabaticity (GOIA) pulses in addition to the routine mp-MRI, including T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI) and quantitative dynamic contrast enhancement (DCE) for transition zone prostate cancer detection, localization and grading. METHODS: Forty-one transition zone prostate cancer patients underwent mp-MRI with an external phased-array coil. Normal and cancer regions were delineated by two radiologists and divided into low-risk, intermediate-risk, and high-risk categories based on TRUS guided biopsy results. Support vector machine models were built using different clinically applicable combinations of T2WI, DWI, DCE, and MRSI. The diagnostic performance of each model in cancer detection was evaluated using the area under curve (AUC) of the receiver operating characteristic diagram. Then accuracy, sensitivity and specificity of each model were calculated. Furthermore, the correlation of mp-MRI parameters with low-risk, intermediate-risk and high-risk cancers were calculated using the Spearman correlation coefficient. RESULTS: The addition of MRSI to T2WI + DWI and T2WI + DWI + DCE improved the accuracy, sensitivity and specificity for cancer detection. The best performance was achieved with T2WI + DWI + MRSI where the addition of MRSI improved the AUC, accuracy, sensitivity and specificity from 0.86 to 0.99, 0.83 to 0.96, 0.80 to 0.95, and 0.85 to 0.97 respectively. The (choline + spermine + creatine)/citrate ratio of MRSI showed the highest correlation with cancer risk groups (r = 0.64, p < 0.01). CONCLUSION: The inclusion of GOIA-sLASER MRSI into conventional mp-MRI significantly improves the diagnostic accuracy of the detection and aggressiveness assessment of transition zone prostate cancer.


Assuntos
Espectroscopia de Ressonância Magnética/uso terapêutico , Imageamento por Ressonância Magnética Multiparamétrica/estatística & dados numéricos , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/diagnóstico por imagem
14.
Cochrane Database Syst Rev ; 5: CD011220, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34037241

RESUMO

BACKGROUND: Retrospective analyses suggest that capecitabine may carry superior activity in hormone receptor-positive relative to hormone receptor-negative metastatic breast cancer. This review examined the veracity of that finding and explored whether this differential activity extends to early breast cancer. OBJECTIVES: To assess effects of chemotherapy regimens containing capecitabine compared with regimens not containing capecitabine for women with hormone receptor-positive versus hormone receptor-negative breast cancer across the three major treatment scenarios: neoadjuvant, adjuvant, metastatic. SEARCH METHODS: On 4 June 2019, we searched the Cochrane Breast Cancer Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 5) in the Cochrane Library; MEDLINE; Embase; the World Health Organization International Clinical Trials Registry Platform; and ClinicalTrials.gov. SELECTION CRITERIA: Randomised controlled trials looking at chemotherapy regimens containing capecitabine alone or in combination with other agents versus a control or similar regimen without capecitabine for treatment of breast cancer at any stage. The primary outcome measure for metastatic and adjuvant trials was overall survival (OS), and for neoadjuvant studies pathological complete response (pCR). DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed risk of bias and certainty of evidence using the GRADE approach. Hazard ratios (HRs) were derived for time-to-event outcomes, and odds ratios (ORs) for dichotomous outcomes, and meta-analysis was performed using a fixed-effect model. MAIN RESULTS: We included 26 studies with outcome data by hormone receptor: 12 metastatic studies (n = 4325), 6 neoadjuvant trials (n = 3152), and 8 adjuvant studies (n = 13,457). Capecitabine treatment was added in several different ways across studies. These could be classified as capecitabine alone compared to another treatment, capecitabine substituted for part of the control chemotherapy, and capecitabine added to control chemotherapy. In the metastatic setting, the effect of capecitabine was heterogenous between hormone receptor-positive and -negative tumours. For OS, no difference between capecitabine-containing and non-capecitabine-containing regimens was observed for all participants taken together (HR 1.01, 95% confidence interval (CI) 0.98 to 1.05; 12 studies, 4325 participants; high-certainty evidence), for those with hormone receptor-positive disease (HR 0.93, 95% CI 0.84 to 1.04; 7 studies, 1834 participants; high-certainty evidence), and for those with hormone receptor-negative disease (HR 1.00, 95% CI 0.88 to 1.13; 8 studies, 1577 participants; high-certainty evidence). For progression-free survival (PFS), a small improvement was seen for all people (HR 0.89, 95% CI 0.82 to 0.96; 12 studies, 4325 participants; moderate-certainty evidence). This was largely accounted for by a moderate improvement in PFS for inclusion of capecitabine in hormone receptor-positive cancers (HR 0.82, 95% CI 0.73 to 0.91; 7 studies, 1594 participants; moderate-certainty evidence) compared to no difference in PFS for hormone receptor-negative cancers (HR 0.96, 95% CI 0.83 to 1.10; 7 studies, 1122 participants; moderate-certainty evidence). Quality of life was assessed in five studies; in general there did not seem to be differences in global health scores between the two treatment groups at around two years' follow-up. Neoadjuvant studies were highly variable in design, having been undertaken to test various experimental regimens using pathological complete response (pCR) as a surrogate for disease-free survival (DFS) and OS. Across all patients, capecitabine-containing regimens resulted in little difference in pCR in comparison to non-capecitabine-containing regimens (odds ratio (OR) 1.12, 95% CI 0.94 to 1.33; 6 studies, 3152 participants; high-certainty evidence). By subtype, no difference in pCR was observed for either hormone receptor-positive (OR 1.22, 95% CI 0.76 to 1.95; 4 studies, 964 participants; moderate-certainty evidence) or hormone receptor-negative tumours (OR 1.28, 95% CI 0.61 to 2.66; 4 studies, 646 participants; moderate-certainty evidence). Four studies with 2460 people reported longer-term outcomes: these investigators detected no difference in either DFS (HR 1.02, 95% CI 0.86 to 1.21; high-certainty evidence) or OS (HR 0.97, 95% CI 0.77 to 1.23; high-certainty evidence). In the adjuvant setting, a modest improvement in OS was observed across all participants (HR 0.89, 95% CI 0.81 to 0.98; 8 studies, 13,547 participants; moderate-certainty evidence), and no difference in OS was seen in hormone receptor-positive cancers (HR 0.86, 95% CI 0.68 to 1.09; 3 studies, 3683 participants), whereas OS improved in hormone receptor-negative cancers (HR 0.72, 95% CI 0.59 to 0.89; 5 studies, 3432 participants). No difference in DFS or relapse-free survival (RFS) was observed across all participants (HR 0.93, 95% CI 0.86 to 1.01; 8 studies, 13,457 participants; moderate-certainty evidence). As was observed for OS, no difference in DFS/RFS was seen in hormone receptor-positive cancers (HR 1.03, 95% CI 0.91 to 1.17; 5 studies, 5604 participants; moderate-certainty evidence), and improvements in DFS/RFS with inclusion of capecitabine were observed for hormone receptor-negative cancers (HR 0.74, 95% CI 0.64 to 0.86; 7 studies, 3307 participants; moderate-certainty evidence). Adverse effects were reported across all three scenarios. When grade 3 or 4 febrile neutropenia was considered, no difference was seen for capecitabine compared to non-capecitabine regimens in neoadjuvant studies (OR 1.31, 95% CI 0.97 to 1.77; 4 studies, 2890 participants; moderate-certainty evidence), and a marked reduction was seen for capecitabine in adjuvant studies (OR 0.55, 95% CI 0.47 to 0.64; 5 studies, 8086 participants; moderate-certainty evidence). There was an increase in diarrhoea and hand-foot syndrome in neoadjuvant (diarrhoea: OR 1.95, 95% CI 1.32 to 2.89; 3 studies, 2686 participants; hand-foot syndrome: OR 6.77, 95% CI 4.89 to 9.38; 5 studies, 3021 participants; both moderate-certainty evidence) and adjuvant trials (diarrhoea: OR 2.46, 95% CI 2.01 to 3.01; hand-foot syndrome: OR 13.60, 95% CI 10.65 to 17.37; 8 studies, 11,207 participants; moderate-certainty evidence for both outcomes). AUTHORS' CONCLUSIONS: In summary, a moderate PFS benefit by including capecitabine was seen only in hormone receptor-positive cancers in metastatic studies. No benefit of capecitabine for pCR was noted overall or in hormone receptor subgroups when included in neoadjuvant therapy. In contrast, the addition of capecitabine in the adjuvant setting led to improved outcomes for OS and DFS in hormone receptor-negative cancer. Future studies should stratify by hormone receptor and triple-negative breast cancer (TNBC) status to clarify the differential effects of capecitabine in these subgroups across all treatment scenarios, to optimally guide capecitabine inclusion.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Capecitabina/uso terapêutico , Antimetabólitos Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Viés , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Capecitabina/efeitos adversos , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Terapia Neoadjuvante , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
15.
Cancer Immunol Res ; 9(2): 136-146, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33303574

RESUMO

Combined inhibition of BRAF, MEK, and CDK4/6 is currently under evaluation in clinical trials for patients with melanoma harboring a BRAFV600 mutation. While this triple therapy has potent tumor-intrinsic effects, the impact of this combination on antitumor immunity remains unexplored. Here, using a syngeneic BrafV600ECdkn2a-/-Pten-/- melanoma model, we demonstrated that triple therapy promoted durable tumor control through tumor-intrinsic mechanisms and promoted immunogenic cell death and T-cell infiltration. Despite this, tumors treated with triple therapy were unresponsive to immune checkpoint blockade (ICB). Flow cytometric and single-cell RNA sequencing analyses of tumor-infiltrating immune populations revealed that triple therapy markedly depleted proinflammatory macrophages and cross-priming CD103+ dendritic cells, the absence of which correlated with poor overall survival and clinical responses to ICB in patients with melanoma. Indeed, immune populations isolated from tumors of mice treated with triple therapy failed to stimulate T-cell responses ex vivo While combined BRAF, MEK, and CDK4/6 inhibition demonstrates favorable tumor-intrinsic activity, these data suggest that collateral effects on tumor-infiltrating myeloid populations may impact antitumor immunity. These findings have important implications for the design of combination strategies and clinical trials that incorporate BRAF, MEK, and CDK4/6 inhibition with immunotherapy for the treatment of patients with melanoma.


Assuntos
Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Imunoterapia/métodos , Melanoma/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Animais , Quinase 4 Dependente de Ciclina/imunologia , Masculino , Melanoma/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Quinases de Proteína Quinase Ativadas por Mitógeno/imunologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
17.
J Appl Clin Med Phys ; 21(10): 179-191, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32770600

RESUMO

PURPOSE: The aim of this study was to develop and assess the performance of supervised machine learning technique to classify magnetic resonance imaging (MRI) voxels as cancerous or noncancerous using noncontrast multiparametric MRI (mp-MRI), comprised of T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and advanced diffusion tensor imaging (DTI) parameters. MATERIALS AND METHODS: In this work, 191 radiomic features were extracted from mp-MRI from prostate cancer patients. A comprehensive set of support vector machine (SVM) models for T2WI and mp-MRI (T2WI + DWI, T2WI + DTI, and T2WI + DWI + DTI) were developed based on novel Bayesian parameters optimization method and validated using leave-one-patient-out approach to eliminate any possible overfitting. The diagnostic performance of each model was evaluated using the area under the receiver operating characteristic curve (AUROC). The average sensitivity, specificity, and accuracy of the models were evaluated using the test data set and the corresponding binary maps generated. Finally, the SVM plus sigmoid function of the models with the highest performance were used to produce cancer probability maps. RESULTS: The T2WI + DWI + DTI models using the optimal feature subset achieved the best performance in prostate cancer detection, with the average AUROC , sensitivity, specificity, and accuracy of 0.93 ± 0.03, 0.85 ± 0.05, 0.82 ± 0.07, and 0.83 ± 0.04, respectively. The average diagnostic performance of T2WI + DTI models was slightly higher than T2WI + DWI models (+3.52%) using the optimal radiomic features. CONCLUSIONS: Combination of noncontrast mp-MRI (T2WI, DWI, and DTI) features with the framework of a supervised classification technique and Bayesian optimization method are able to differentiate cancer from noncancer voxels with high accuracy and without administration of contrast agent. The addition of cancer probability maps provides additional functionality for image interpretation, lesion heterogeneity evaluation, and treatment management.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Teorema de Bayes , Imagem de Tensor de Difusão , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos , Sensibilidade e Especificidade , Aprendizado de Máquina Supervisionado
18.
Int J Infect Dis ; 98: 59-66, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535300

RESUMO

OBJECTIVES: Melioidosis is associated with extremely high case fatality ratios. The aim of this study was to determine whether detection of abdominal visceral abscesses can facilitate diagnosis of melioidosis in children. METHODS: We conducted a retrospective analysis of all children who had liver and/or spleen abscesses on abdominal ultrasonography admitted to Bintulu Hospital in Sarawak, Malaysia, from January 2014 until December 2018. RESULTS: Fifty-three children had liver and/or spleen abscesses. Spleen abscesses were present in 48 (91%) cases; liver abscesses in 15 (28%). Melioidosis was confirmed by culture in 9 (17%) children; small occult splenic abscesses were present in all cases. In 78% of these cases, the lesions were detected before any positive culture (or serology) results were available. Four (8%) children had bacteriologically-confirmed tuberculosis. Two (4%) had Staphylococcus aureus infection. Of the remaining 38 (72%) culture-negative cases, 36 (95%) had clinical and imaging characteristics similar to that of children with culture-confirmed melioidosis and improved with empirical melioidosis antibiotic therapy. CONCLUSIONS: A large number of children in Bintulu Hospital in Sarawak, Malaysia, were found to have spleen abscesses. Melioidosis was the most common etiology identified in these children. Abdominal ultrasonography is extremely useful in facilitating the diagnosis of pediatric melioidosis.


Assuntos
Melioidose/diagnóstico , Esplenopatias/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Infecções Intra-Abdominais , Abscesso Hepático/diagnóstico , Abscesso Hepático/diagnóstico por imagem , Abscesso Hepático/epidemiologia , Malásia/epidemiologia , Masculino , Melioidose/diagnóstico por imagem , Melioidose/epidemiologia , Estudos Retrospectivos , Esplenopatias/diagnóstico por imagem , Esplenopatias/epidemiologia , Ultrassonografia
19.
Eur J Nucl Med Mol Imaging ; 47(12): 2776-2786, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32338306

RESUMO

PURPOSE: We aimed to investigate the role of FDG-PET/CT in monitoring of response and immune-related adverse events (irAEs) following first-line combination-immune checkpoint inhibitor (combination-ICI) therapy for advanced melanoma. METHODS: We retrospectively reviewed outcomes in patients who had (1) first-line nivolumab plus ipilimumab; (2) pre- and post-treatment FDG-PET/CT scans (pre-FDG-PET/CT and post-FDG-PET/CT) within 2 and 4 months of starting ICI, respectively; and (3) at least one lesion assessable by PET response criteria in solid tumors (PERCIST). Extracranial response was monitored by 3 monthly FDG-PET/CT. Whole-body metabolic tumor volume (wbMTV) was measured pre- and post-treatment and correlated with outcome. FDG-PET/CT manifestations of irAE were defined as new increased non-tumoral uptake on post-FDG-PET/CT and were correlated with clinical presentation. RESULTS: Thirty-one consecutive patients, median age 60 years (range, 30-78), were identified from 2016 to 2018. The median number of combination-ICI cycles to the first post-FDG-PET/CT response assessment was 3 (interquartile range (IQR), 2-4). The best-overall responses were complete metabolic response (CMR) in 25 (80%), partial metabolic response (PMR) in 3 (10%), and progressive metabolic disease (PMD) in 3 (10%) patients. Patients with PMD had significantly higher pre-treatment wbMTV (p = 0.009). At a median follow-up of 21.5 months, 26 (84%) patients were alive with median progression-free and overall survival not reached. Secondary progression occurred in 9/31 (29%) patients at a median of 8.2 months (IQR, 6.9-15.5), of those majority (78%) was detected by FDG-PET/CT. Of 36 findings on post-FDG-PET/CT suggestive of irAE, 29 (80%) had clinical confirmation. In 3 (7%), the FDG-PET/CT findings preceded clinical presentation. The most common FDG-PET/CT detectable irAEs were endocrinopathies (36%) and enterocolitis (35%). CONCLUSION: FDG-PET/CT response evaluation predicts the long-term outcome of patients treated with first-line combination-ICIs. Long-term treatment response monitoring for detection of extracranial secondary progression is feasible by FDG-PET/CT. Beyond response assessment, FDG-PET/CT frequently detects clinically relevant irAEs, which may involve multiple systems contemporaneously or at various time-points and may precede clinical diagnosis.


Assuntos
Melanoma , Nivolumabe , Fluordesoxiglucose F18 , Humanos , Imunidade , Ipilimumab/efeitos adversos , Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Nivolumabe/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Resultado do Tratamento
20.
Cancer Res ; 80(6): 1304-1315, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941699

RESUMO

Metastasis is the major cause of death in patients with cancer; with no therapeutic cure, treatments remain largely palliative. As such, new targets and therapeutic strategies are urgently required. Here, we show that bone morphogenetic protein-4 (BMP4) blocks metastasis in animal models of breast cancer and predicts improved survival in patients. In preclinical models of spontaneous metastasis, BMP4 acted as an autocrine mediator to modulate a range of known metastasis-regulating genes, including Smad7, via activation of canonical BMP-SMAD signaling. Restored BMP4 expression or therapeutically administered BMP4 protein, blocked metastasis and increased survival by sensitizing cancer cells to anoikis, thereby reducing the number of circulating tumor cells. Gene silencing of Bmp4 or its downstream mediator Smad7, reversed this phenotype. Administration of recombinant BMP4 markedly reduced spontaneous metastasis to lung and bone. Elevated levels of BMP4 and SMAD7 were prognostic for improved recurrence-free survival and overall survival in patients with breast cancer, indicating the importance of canonical BMP4 signaling in the suppression of metastasis and highlighting new avenues for therapy against metastatic disease. SIGNIFICANCE: Targeting the BMP4-SMAD7 signaling axis presents a novel therapeutic strategy to combat metastatic breast cancer, a disease that has had no reduction in patient mortality over 20 years. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/6/1304/F1.large.jpg.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Neoplasias Ósseas/genética , Neoplasias da Mama/patologia , Proteína Smad7/metabolismo , Animais , Comunicação Autócrina , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/uso terapêutico , Neoplasias Ósseas/prevenção & controle , Neoplasias Ósseas/secundário , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Linhagem Celular Tumoral/transplante , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Glândulas Mamárias Animais/patologia , Mastectomia , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica/patologia , Metástase Neoplásica/prevenção & controle , Prognóstico , Proteínas Recombinantes/uso terapêutico , Transdução de Sinais/genética , Proteína Smad4/metabolismo , Proteína Smad7/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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