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1.
Chest ; 165(4): e95-e100, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38599764

RESUMO

CASE PRESENTATION: A 52-year-old woman with no significant medical history was referred to our hospital for expedited workup of progressive dysarthria and ataxia over the past year. Prior CT angiography of the head and neck showed no relevant neurologic findings but did reveal miliary lesions in the lung apices, which was later confirmed via dedicated CT chest scan (Fig 1). Review of systems was negative for any respiratory, constitutional, or rheumatologic symptoms, except for new xanthelasma-like lesions over her forehead. She previously had smoked with 20 pack-years and had no TB risk factors. MRI of the face showed a 21-mm mass within the left external temporal fascia. MRI of the head showed diffuse leptomeningeal enhancement, right frontal lobe enhancement, and cerebellar and brainstem T2/fluid-attenuated inversion recovery hyperintensity, which prompted her admission to hospital.


Assuntos
Ataxia Cerebelar , Disartria , Humanos , Feminino , Pessoa de Meia-Idade , Pulmão/patologia , Tomografia Computadorizada por Raios X , Pescoço
2.
ACS Chem Biol ; 19(4): 926-937, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38477945

RESUMO

Invariant natural killer T (iNKT) cells play an important role in many innate and adaptive immune responses, with potential applications in cancer immunotherapy. The glycolipid KRN7000, an α-galactosylceramide, potently activates iNKT cells but has shown limited anticancer effects in human clinical trials conducted so far. In spite of almost three decades of structure-activity relationship studies, no alternative glycolipid has yet emerged as a superior clinical candidate. One reason for the slow progress in this area is that standard mouse models do not accurately reflect the specific ligand recognition by human iNKT cells and their requirements for activation. Here we evaluated a series of KRN7000 analogues using a recently developed humanized mouse model that expresses a human αTCR chain sequence and human CD1d. In this process, a more stimulatory, previously reported but largely overlooked glycolipid was identified, and its activity was probed and rationalized via molecular simulations.


Assuntos
Galactosilceramidas , Glicolipídeos , Células T Matadoras Naturais , Animais , Humanos , Camundongos , Antígenos CD1d , Glicolipídeos/agonistas
3.
Oral Oncol ; 151: 106717, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412584

RESUMO

OBJECTIVES: The incidence of head and neck squamous cell carcinoma (HNSCC) continues to increase and although advances have been made in treatment, it still has a poor overall survival with local relapse being common. Conventional imaging methods are not efficient at detecting recurrence at an early stage when still potentially curable. The aim of this study was to test the feasibility of using saliva to detect the presence of oral squamous cell carcinoma (OSCC) and to provide additional evidence for the potential of this approach. MATERIALS AND METHODS: Fresh tumor, whole blood and saliva were collected from patients with OSCC before treatment. Whole exome sequencing (WES) or gene panel sequencing of tumor DNA was performed to identify somatic mutations in tumors and to select genes for performing gene panel sequencing on saliva samples. RESULTS: The most commonly mutated genes identified in primary tumors by DNA sequencing were TP53 and FAT1. Gene panel sequencing of paired saliva samples detected tumor derived mutations in 9 of 11 (82%) patients. The mean variant allele frequency for the mutations detected in saliva was 0.025 (range 0.004 - 0.061). CONCLUSION: Somatic tumor mutations can be detected in saliva with high frequency in OSCC irrespective of site or stage of disease using a limited panel of genes. This work provides additional evidence for the suitability of using saliva as liquid biopsy in OSCC and has the potential to improve early detection of recurrence in OSCC. Trials are currently underway comparing this approach to standard imaging techniques.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Saliva , Recidiva Local de Neoplasia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Mutação , Biomarcadores Tumorais/genética
4.
JBJS Case Connect ; 13(4)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38096339

RESUMO

CASE: There is an increasing emphasis on adverse reactions to metal debris around prosthetic hip implants. We present a case report of a patient with increasing pain around a previous total hip arthroplasty and magnetic resonance imaging findings consistent with a pseudotumor. Serum metal ion levels were not elevated and initial biopsy findings inconclusive. The patient was diagnosed with an extraskeletal chondrosarcoma after revision total hip arthroplasty and subsequently underwent external hemipelvectomy with negative margins. CONCLUSION: This report highlights the importance of remaining vigilant for malignant sarcomas presenting as pseudotumors around hip replacements, particularly in the absence of abnormal metal ion levels or definitive biopsy results.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Próteses Articulares Metal-Metal , Sarcoma , Humanos , Artroplastia de Quadril/efeitos adversos , Cobalto , Prótese de Quadril/efeitos adversos , Próteses Articulares Metal-Metal/efeitos adversos , Metais/efeitos adversos , Desenho de Prótese , Sarcoma/diagnóstico , Sarcoma/etiologia , Sarcoma/cirurgia , Diagnóstico Diferencial
5.
J Cell Immunol ; 5(4): 97-102, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37946751

RESUMO

Vaccines are among the most effective tools for combatting the impact and spread of infectious diseases. However, the effectiveness of a vaccine can be diminished by vaccine inequality, particularly during severe outbreaks of infectious diseases in resource-poor areas. As seen in many developing countries that lack adequate healthcare infrastructure and economic resources, the acquisition and distribution of potentially life-saving vaccines may be limited, leading to prolonged suffering and increased deaths. To improve vaccine equity, vaccine design must take into consideration the logistics needed to implement a successful vaccination drive, particularly among the most vulnerable populations. In the manuscript titled "Exploiting Pre-Existing CD4+ T Cell Help from Bacille Calmette-Guérin Vaccination to Improve Antiviral Antibody Responses" published in the Journal of Immunology, the authors designed a recombinant subunit vaccine against the Ebola virus (EBOV) glycoprotein that can harness the pre-existing T helper cells from prior BCG vaccination. As a recombinant subunit vaccine adjuvanted with alum, this approach has many features that make it well suited for the design of vaccines for developing nations, such as relative ease of production, scalability, and distribution. In addition, the high prevalence of BCG immunization and natural immunity to mycobacteria in many regions of the world endow such vaccines with features that should increase potency and efficacy among populations residing in such regions. As a result of using the helper activity of pre-existing BCG-specific Th cells to drive antibody responses, a lower vaccine dose is needed, which is a major advantage for vaccine manufacture. Furthermore, the BCG-specific Th cells also stimulate immunoglobulin class switching to IgG isotypes that have strong affinities for activating Fc-gamma receptors (FcγRs). Taken together, we propose that the design of subunit vaccines with intrastructural help from BCG-specific Th cells can improve protection against viral infection and represents a vaccine design that can be generally adapted to other emerging viral pathogens for the control and prevention of infection in many developing countries.

6.
Cureus ; 15(10): e47890, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38034191

RESUMO

INTRODUCTION: The shoulder is one of the joints most affected by osteoarthritis, with a prevalence of almost 20% in adults over 65 years of age. Various treatments have been proposed to control osteoarthritis pain, including radiofrequency, pulsed and thermal, and recently cryoanalgesia. We propose in this series of cases a new approach to analgesic therapy with chemical denervation with phenol. MATERIALS AND METHOD: Patients who underwent phenolysis for shoulder osteoarthritis at our institutions in Italy and Australia between August 2022 and May 2023 were included. All patients included in our report provided written consent for publication. This chemical neurolysis technique consisted of two injections. First, the anterior shoulder capsule was denervated by a modified deep SHAC (Shoulder Anterior Capsule) approach to cover the anterior terminal articular branches of the axillary nerve, lateral pectoral nerve, and subscapularis nerve. Second, the posterior shoulder capsule was denervated by a posterior glenoid approach to cover the terminal articular branches of the suprascapular nerve (SSN).  Results: We included a total of 11 patients in this case series. Ten of 11 patients were affected by shoulder osteoarthritis, of which three had rotator cuff tendinopathy and three had full-thickness cuff tears. One patient had chronic subluxation of a shoulder prosthesis. After treatment, all patients significantly reduced pain immediately after treatment and, two weeks later, recovered joint movement and improved quality of life. No adverse events or loss of motor function following treatment. CONCLUSION: We presented a novel chemical approach to shoulder denervation, which was shown to be another effective way of improving pain and function in advanced glenohumeral arthritis.

7.
Br J Cancer ; 129(12): 1877-1892, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37794178

RESUMO

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.


Assuntos
Neoplasias , Tiorredoxinas , Humanos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Glucose , Inflamação , Neoplasias/imunologia , Neoplasias/metabolismo , Oxirredução , Tiorredoxinas/metabolismo , Microambiente Tumoral
8.
Mod Pathol ; 36(12): 100348, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37820765

RESUMO

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.


Assuntos
Papillomavirus Humano , Infecções por Papillomavirus , Humanos , Imuno-Histoquímica , Infecções por Papillomavirus/patologia , Proteína Supressora de Tumor p53/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , RNA , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Papillomaviridae/genética
9.
Pharm Res ; 40(11): 2699-2714, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37726406

RESUMO

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.


Assuntos
Anticarcinógenos , Neoplasias Pulmonares , Neoplasias , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/patologia , Anticarcinógenos/uso terapêutico , Dieta , Proteômica , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Biomarcadores
10.
Front Immunol ; 14: 1204224, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37441083

RESUMO

Background: Intracellular communication within the tumour is complex and extracellular vesicles (EVs) have been identified as major contributing factors for the cell-to-cell communication in the local and distant tumour environments. Here, we examine the differential effects of breast cancer (BC) subtype-specific patient serum and cell-line derived EVs in the regulation of T cell mediated immune responses. Methods: Ultracentrifugation was used to isolate EVs from sera of 63 BC patients, 15 healthy volunteers and 4 human breast cancer cell lines. Longitudinal blood draws for EV isolation for patients on neoadjuvant chemotherapy was also performed. Characterization of EVs was performed by Nanoparticle Tracking Analysis (NTA), transmission electron microscopy (TEM) and immunoblotting. CD63 staining was performed on a tissue microarray of 218 BC patients. In-house bioinformatics algorithms were utilized for the computation of EV associated expression scores within The Cancer Genome Atlas (TCGA) and correlated with tumour infiltrating lymphocyte (TIL) scores. In vitro stimulation of PBMCs with EVs from serum and cell-line derived EVs was performed and changes in the immune phenotypes characterized by flow cytometry. Cytokine profiles were assessed using a 105-plex immunoassay or IL10 ELISA. Results: Patients with triple negative breast cancers (TNBCs) exhibited the lowest number of EVs in the sera; whilst the highest was detected in ER+HER2+ cancers; reflected also in the higher level of CD63+ vesicles found within the ER+HER2+ local tumour microenvironment. Transcriptomic analysis of the TCGA data identified that samples assigned with lower EV scores had significantly higher abundance of CD4+ memory activated T cells, T follicular cells and CD8 T cells, plasma, and memory B cells; whilst samples with high EV scores were more enriched for anti-inflammatory M2 macrophages and mast cells. A negative correlation between EV expression scores and stromal TIL counts was also observed. In vitro experiments confirmed that circulating EVs within breast cancer subtypes have functionally differing immunomodulatory capabilities, with EVs from patients with the most aggressive breast cancer subtype (TNBCs) demonstrating the most immune-suppressive phenotype (decreased CD3+HLA-DR+ but increased CD3+PD-L1 T cells, increased CD4+CD127-CD25hi T regulatory cells with associated increase in IL10 cytokine production). In depth assessment of the cytokine modulation triggered by the serum/cell line derived exosomes confirmed differential inflammatory cytokine profiles across differing breast cancer subtypes. Studies using the MDA-231 TNBC breast cancer cell-line derived EVs provided further support that TNBC EVs induced the most immunosuppressive response within PBMCs. Discussion: Our study supports further investigations into how tumour derived EVs are a mechanism that cancers can exploit to promote immune suppression; and breast cancer subtypes produce EVs with differing immunomodulatory capabilities. Understanding the intracellular/extracellular pathways implicated in alteration from active to suppressed immune state may provide a promising way forward for restoring immune competence in specific breast cancer patient populations.


Assuntos
Vesículas Extracelulares , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/metabolismo , Interleucina-10/metabolismo , Citocinas/metabolismo , Células MCF-7 , Vesículas Extracelulares/metabolismo , Microambiente Tumoral
11.
Dev Cell ; 58(17): 1548-1561.e10, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37442140

RESUMO

Tumor-associated macrophages (TAMs) are a heterogeneous population of cells that facilitate cancer progression. However, our knowledge of the niches of individual TAM subsets and their development and function remain incomplete. Here, we describe a population of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1)-expressing TAMs, which form coordinated multi-cellular "nest" structures that are heterogeneously distributed proximal to vasculature in tumors of a spontaneous murine model of breast cancer. We demonstrate that LYVE-1+ TAMs develop in response to IL-6, which induces their expression of the immune-suppressive enzyme heme oxygenase-1 and promotes a CCR5-dependent signaling axis, which guides their nest formation. Blocking the development of LYVE-1+ TAMs or their nest structures, using gene-targeted mice, results in an increase in CD8+ T cell recruitment to the tumor and enhanced response to chemotherapy. This study highlights an unappreciated collaboration of a TAM subset to form a coordinated niche linked to immune exclusion and resistance to anti-cancer therapy.


Assuntos
Neoplasias , Camundongos , Animais , Neoplasias/patologia , Macrófagos/metabolismo
12.
OTO Open ; 7(2): e50, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275458

RESUMO

Objective: Laryngeal verrucous carcinoma (LVC) comprises 1% to 4% of all laryngeal tumors. Although controversial, surgery has been the mainstay of treatment, due to concern about anaplastic transformation with radiotherapy. We aimed to study LVC patients to identify treatment patterns for primary and recurrent diseases. Study Design: Retrospective cohort study. Setting: Tertiary referral center. Methods: Patients with a pathological diagnosis of LVC treated over a 28-year period were included. Baseline demographics, and treatment outcome measures including 5-year laryngeal preservation rates (LPR), overall survival (OS), and recurrence-free survival (RFS) were included. A literature review of published studies within the same study period was also completed. Results: Thirty-two patients were included in the analysis (median age 61.5 years, 93.8% [30/32] male). Twenty-three patients had T1 disease, and 9 had T2 disease with no evidence of regional or metastatic disease. The most common presenting symptom was hoarseness (93.8%) and the majority within the glottis 81.3% (26/32). Twenty-nine patients underwent primary surgery only (28 local excisions, 1 vertical partial laryngectomy) meanwhile 3 underwent local excision with postoperative radiotherapy. LPR, OS, and RFS at 5 years were 95.8%, 90.1%, and 80.6%, respectively. Our literature review identified 23 previous studies, mostly single-institution retrospective case series. Our study was the largest Canadian study in the literature to date. Conclusion: All LVC patients were treated with primary surgery, consistent with the current literature with excellent 5-year OS and LPR. There was no consensus on the treatment of recurrent disease. Future prospective multicenter studies are warranted to further study this rare disease population.

13.
BMJ Open ; 13(6): e068740, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380211

RESUMO

INTRODUCTION: Online multiple-choice question (MCQ) quizzes are popular in medical education due to their ease of access and ability for test-enhanced learning. However, a general lack of motivation among students often results in decreasing usage over time. We aim to address this limitation by developing Telegram Education for Surgical Learning and Application Gamified (TESLA-G), an online platform for surgical education that incorporates game elements into conventional MCQ quizzes. METHODS AND ANALYSIS: This online, pilot randomised control trial will be conducted over 2 weeks. Fifty full-time undergraduate medical students from a medical school in Singapore will be recruited and randomised into an intervention group (TESLA-G) and an active control group (non-gamified quizzing platform) with a 1:1 allocation ratio, stratified by year of study.We will evaluate TESLA-G in the area of endocrine surgery education. Our platform is designed based on Bloom's taxonomy of learning domains: questions are created in blocks of five questions per endocrine surgery topic, with each question corresponding to one level on Bloom's taxonomy. This structure promotes mastery while boosting student engagement and motivation. All questions are created by two board-certified general surgeons and one endocrinologist, and validated by the research team. The feasibility of this pilot study will be determined quantitatively by participant enrolment, participant retention and degree of completion of the quizzes. The acceptability of the intervention will be assessed quantitatively by a postintervention learner satisfaction survey consisting of a system satisfaction questionnaire and a content satisfaction questionnaire. The improvement of surgical knowledge will be assessed by comparing the scores of preintervention and postintervention knowledge tests, which consist of separately created questions on endocrine surgery. Retention of surgical knowledge will be measured using a follow-up knowledge test administered 2 weeks postintervention. Finally, qualitative feedback from participants regarding their experience will be obtained and thematically analysed. ETHICS AND DISSEMINATION: This research is approved by Singapore Nanyang Technological University (NTU) Institutional Review Boards (Reference Number: IRB-2021-732). All participants will be expected to read and sign a letter of informed consent before they are considered as recruited into the study. This study poses minimal risk to participants. Study results will be published in peer-reviewed open-access journals and presented in conference presentations. TRIAL REGISTRATION NUMBER: NCT05520671.


Assuntos
Estudantes de Medicina , Humanos , Projetos Piloto , Escolaridade , Aprendizagem , Motivação , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Ocul Surf ; 28: 144-152, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37011726

RESUMO

Superior limbic keratoconjunctivitis (SLK) is an under-recognized condition characterized by a final common pathologic presentation of superior conjunctival and limbal inflammation and staining. Existing literature attributes both microtrauma and local inflammation, frequently in the setting of tear film insufficiency, as the underlying mechanisms that lead to a self-perpetuating pathologic process dependent in on inflammatory cells and signaling. Effective treatments act by targeting inflammation and by mitigating mechanical stressors. This critical review discusses the latest in our understanding of the pathophysiology of SLK and how it guides our treatment strategies.


Assuntos
Ceratoconjuntivite , Limbo da Córnea , Humanos , Limbo da Córnea/patologia , Ceratoconjuntivite/terapia , Ceratoconjuntivite/patologia , Túnica Conjuntiva/patologia , Inflamação/patologia , Resultado do Tratamento
15.
Appl Immunohistochem Mol Morphol ; 31(5): 304-310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37036408

RESUMO

Tumors of the central nervous system (CNS) in pediatric patients have undergone significant diagnostic refinement through the use of immunohistochemistry (IHC) and molecular techniques. The utility of these novel IHC antibodies has been demonstrated with the inactivation of the switch/sucrose nonfermenting (SWI/SNF) chromatin-remodeling complex in the diagnosis of atypical teratoid/rhabdoid tumors, predominantly through the loss of integrase interactor 1 (INI1; SMARCB1 ). Alternatively, these tumors may have inactivation of brahma-related gene 1 (BRG1; SMARCA4 ) in a subset of cases. The role of other SWI/SNF component proteins and their expression in pediatric brain tumors is not well established. Nestin, an intermediate filament, has been shown to be present in some pediatric CNS tumors, but of uncertain diagnostic and prognostic significance. We sought to explore the immunohistochemical expression profile for common SWI/SNF subunits and nestin in a pediatric CNS tumor cohort. Using a 118-sample tissue microarray, we performed IHC for INI1, BRG1, brahma (BRM), ARID1A, ARID1B, polybromo 1, and nestin. In 19 cases, INI1 was lost and BRG1 was lost in 2 cases. Interestingly, 6 cases originally diagnosed as primitive neuroectodermal tumors showed isolated loss of BRM. Other SWI/SNF proteins did not provide further diagnostic resolution. Nestin was positive in 76.2% of INI1/BRG1-deficient tumors, compared with 29.1% in INI1/BRG1-intact tumors yielding a sensitivity of 76.2%, specificity of 68.0%, and a P value of <0.001, but nestin positivity did not correlate specifically with poor outcomes. In conclusion, we confirm the utility of BRG1 IHC in the workup of pediatric CNS tumors, which may facilitate a difficult diagnosis when conventional markers are inconclusive, or as a first-line marker in cases where intraoperative smears are suggestive of atypical teratoid/rhabdoid tumor. Although nestin expression was associated with SWI/SNF inactivation, it did not yield statistically significant diagnostic or prognostic information in our study. Interestingly, we identified 6 tumors with isolated BRM IHC loss, the significance of which is uncertain but warrants further investigation.


Assuntos
Neoplasias Encefálicas , Humanos , Criança , Nestina , DNA Helicases , Proteínas Nucleares , Fatores de Transcrição
16.
NPJ Precis Oncol ; 7(1): 31, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964191

RESUMO

There is emerging evidence about the predictive role of homologous recombination deficiency (HRD), but this is less defined in gastrointestinal (GI) and thoracic malignancies. We reviewed whole genome (WGS) and transcriptomic (RNA-Seq) data from advanced GI and thoracic cancers in the Personalized OncoGenomics trial (NCT02155621) to evaluate HRD scores and single base substitution (SBS)3, which is associated with BRCA1/2 mutations and potentially predictive of defective HRD. HRD scores were calculated by sum of loss of heterozygosity, telomeric allelic imbalance, and large-scale state transitions scores. Regression analyses examined the association between HRD and time to progression on platinum (TTPp). We included 223 patients with GI (n = 154) or thoracic (n = 69) malignancies. TTPp was associated with SBS3 (p < 0.01) but not HRD score in patients with GI malignancies, whereas neither was associated with TTPp in thoracic malignancies. Tumors with gBRCA1/2 mutations and a somatic second alteration exhibited high SBS3 and HRD scores, but these signatures were also present in several tumors with germline but no somatic second alterations, suggesting silencing of the wild-type allele or BRCA1/2 haploinsufficiency. Biallelic inactivation of an HR gene, including loss of XRCC2 and BARD1, was identified in BRCA1/2 wild-type HRD tumors and these patients had prolonged response to platinum. Thoracic cases with high HRD score were associated with high RECQL5 expression (p ≤ 0.025), indicating another potential mechanism of HRD. SBS3 was more strongly associated with TTPp in patients with GI malignancies and may be complementary to using HRD and BRCA status in identifying patients who benefit from platinum therapy.

17.
Mod Pathol ; 36(7): 100153, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36906072

RESUMO

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.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Proteína Supressora de Tumor p53 , Neoplasias Bucais/patologia , Imuno-Histoquímica , Leucoplasia Oral/patologia , Carcinoma de Células Escamosas/patologia , Hiperplasia , Transformação Celular Neoplásica/patologia
18.
J Mol Diagn ; 25(2): 121-131, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36503147

RESUMO

Sarcomas are a diverse group of tumors, with >70 subtypes in the current World Health Organization classification, each with distinct biological behavior requiring specific clinical management. A significant portion of sarcomas are molecularly defined by expression of a driver fusion gene; identification of such fusions is the basis of molecular diagnostics in sarcomas, which is of increasing complexity due to the ongoing discovery of new gene fusions. Recently, a multiplex NanoString platform-based assay was developed and clinically implemented, with fusion junction-spanning probes that detect the majority of sarcoma fusion types, with high sensitivity and specificity, and with lower cost and shorter turnaround time than those of targeted next-generation sequencing-based alternatives. Despite the effectiveness of this assay, there are several entities for which fusion-junction probes are not suitable due to multiple possible gene partners or excessive variability at the exon junctions. Here, the development and evaluation of a companion assay are described that uses NanoString-based gene expression analysis to detect aberrant 3'/5' exon expression imbalance and/or total gene overexpression as a surrogate marker for fusion gene rearrangement. This assay evaluates exon imbalance in 23 genes involved in over 25 mesenchymal tumor types and five genes specific to sarcomas with CIC rearrangements. Based on evaluation of 115 retrospectively and 91 prospectively collected cases, an assay sensitivity of 92.8% and specificity of 93.5% are demonstrated.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Humanos , Estudos Retrospectivos , Sarcoma/diagnóstico , Sarcoma/genética , Sarcoma/patologia , Fusão Gênica , Éxons/genética , Neoplasias de Tecidos Moles/genética , Biomarcadores Tumorais/genética , Expressão Gênica , Proteínas de Fusão Oncogênica/genética
19.
Br J Cancer ; 128(4): 665-677, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36522479

RESUMO

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.


Assuntos
Exossomos , MicroRNAs , Neoplasias , Humanos , MicroRNAs/genética , Doxorrubicina/farmacologia , Neoplasias/patologia , Exossomos/genética , Proteínas Repressoras/metabolismo , Proteínas Supressoras de Tumor/metabolismo
20.
Br J Cancer ; 128(2): 245-254, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36352028

RESUMO

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.


Assuntos
Neoplasias Colorretais , Receptor ErbB-3 , Humanos , Receptor ErbB-3/metabolismo , Transdução de Sinais , Quinazolinas/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/induzido quimicamente , Fluoruracila , Leucovorina/efeitos adversos , Camptotecina , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo
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