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1.
Clin Case Rep ; 12(9): e9123, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39258027

RESUMEN

Key Clinical Message: Gliosarcoma, a rare cerebral neoplasm, has not been linked to hippocampal changes in cats. We report a case of complex partial seizures with orofacial involvement, revealing gliosarcoma concurrent with bilateral hippocampal sclerosis. Abstract: A 16-year-old neutered female domestic shorthair cat presented with acute inappetence, ataxia, disorientation, and vacant staring. Brain MRI revealed an ill-defined, round, intra-axial mass in the right piriform lobe, showing hyperintensity on T2W, T2-FLAIR, and T2*W, and hypointensity on T1W images. The lesion exhibited mass effect and contrast enhancement in its center. Bilateral hyperintensity on T2-FLAIR images and contrast enhancement were observed in the hippocampus. Brain histologic and immunohistochemical analysis revealed cerebral gliosarcoma with concurrent hippocampal sclerosis. Feline LGI1-antibody testing on the serum and/or CSF was not performed due to insufficient biomaterial. Although retrospective testing on brain tissue was considered, it ultimately proved unfeasible, preventing us from ruling out antibody-associated limbic encephalitis. In conclusion, cerebral gliosarcoma should be included in feline intracranial tumor differentials, warranting brain MRI and feline LGI1-antibody testing in cats showing complex partial seizures with orofacial involvement. In our case, the prognosis remained poor due to the presence of a high-grade glioma.

2.
Lancet Oncol ; 25(2): 198-211, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38301689

RESUMEN

BACKGROUND: Tumour-infiltrating CD8+ cytotoxic T cells confer favourable prognosis in colorectal cancer. The added prognostic value of other infiltrating immune cells is unclear and so we sought to investigate their prognostic value in two large clinical trial cohorts. METHODS: We used multiplex immunofluorescent staining of tissue microarrays to assess the densities of CD8+, CD20+, FoxP3+, and CD68+ cells in the intraepithelial and intrastromal compartments from tumour samples of patients with stage II-III colorectal cancer from the SCOT trial (ISRCTN59757862), which examined 3 months versus 6 months of adjuvant oxaliplatin-based chemotherapy, and from the QUASAR 2 trial (ISRCTN45133151), which compared adjuvant capecitabine with or without bevacizumab. Both trials included patients aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 0-1. Immune marker predictors were analysed by multiple regression, and the prognostic and predictive values of markers for colorectal cancer recurrence-free interval by Cox regression were assessed using the SCOT cohort for discovery and QUASAR 2 cohort for validation. FINDINGS: After exclusion of cases without tissue microarrays and with technical failures, and following quality control, we included 2340 cases from the SCOT trial and 1069 from the QUASAR 2 trial in our analysis. Univariable analysis of associations with recurrence-free interval in cases from the SCOT trial showed a strong prognostic value of intraepithelial CD8 (CD8IE) as a continuous variable (hazard ratio [HR] for 75th vs 25th percentile [75vs25] 0·73 [95% CI 0·68-0·79], p=2·5 × 10-16), and of intrastromal FoxP3 (FoxP3IS; 0·71 [0·64-0·78], p=1·5 × 10-13) but not as strongly in the epithelium (FoxP3IE; 0·89 [0·84-0·96], p=1·5 × 10-4). Associations of other markers with recurrence-free interval were moderate. CD8IE and FoxP3IS retained independent prognostic value in bivariable and multivariable analysis, and, compared with either marker alone, a composite marker including both markers (CD8IE-FoxP3IS) was superior when assessed as a continuous variable (adjusted [a]HR75 vs 25 0·70 [95% CI 0·63-0·78], p=5·1 × 10-11) and when categorised into low, intermediate, and high density groups using previously published cutpoints (aHR for intermediate vs high 1·68 [95% CI 1·29-2·20], p=1·3 × 10-4; low vs high 2·58 [1·91-3·49], p=7·9 × 10-10), with performance similar to the gold-standard Immunoscore. The prognostic value of CD8IE-FoxP3IS was confirmed in cases from the QUASAR 2 trial, both as a continuous variable (aHR75 vs 25 0·84 [95% CI 0·73-0·96], p=0·012) and as a categorical variable for low versus high density (aHR 1·80 [95% CI 1·17-2·75], p=0·0071) but not for intermediate versus high (1·30 [0·89-1·88], p=0·17). INTERPRETATION: Combined evaluation of CD8IE and FoxP3IS could help to refine risk stratification in colorectal cancer. Investigation of FoxP3IS cells as an immunotherapy target in colorectal cancer might be merited. FUNDING: Medical Research Council, National Institute for Health Research, Cancer Research UK, Swedish Cancer Society, Roche, and Promedica Foundation.


Asunto(s)
Neoplasias Colorrectales , Recurrencia Local de Neoplasia , Humanos , Estudios Retrospectivos , Recurrencia Local de Neoplasia/patología , Neoplasias Colorrectales/patología , Pronóstico , Linfocitos Infiltrantes de Tumor , Factores de Transcripción Forkhead/uso terapéutico , Estadificación de Neoplasias
3.
Sci Rep ; 14(1): 328, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172189

RESUMEN

H3K27-altered Diffuse Midline Glioma (DMG) is a universally fatal paediatric brainstem tumour. The prevalent driver mutation H3K27M creates a unique epigenetic landscape that may also establish therapeutic vulnerabilities to epigenetic inhibitors. However, while HDAC, EZH2 and BET inhibitors have proven somewhat effective in pre-clinical models, none have translated into clinical benefit due to either poor blood-brain barrier penetration, lack of efficacy or toxicity. Thus, there remains an urgent need for new DMG treatments. Here, we performed wider screening of an epigenetic inhibitor library and identified inhibitors of protein arginine methyltransferases (PRMTs) among the top hits reducing DMG cell viability. Two of the most effective inhibitors, LLY-283 and GSK591, were targeted against PRMT5 using distinct binding mechanisms and reduced the viability of a subset of DMG cells expressing wild-type TP53 and mutant ACVR1. RNA-sequencing and phenotypic analyses revealed that LLY-283 could reduce the viability, clonogenicity and invasion of DMG cells in vitro, representing three clinically important phenotypes, but failed to prolong survival in an orthotopic xenograft model. Together, these data show the challenges of DMG treatment and highlight PRMT5 inhibitors for consideration in future studies of combination treatments.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Tronco Encefálico , Glioma , Niño , Humanos , Barrera Hematoencefálica , Neoplasias del Tronco Encefálico/tratamiento farmacológico , Neoplasias del Tronco Encefálico/genética , Supervivencia Celular , Terapia Combinada , Glioma/tratamiento farmacológico , Glioma/genética , Mutación , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Proteína-Arginina N-Metiltransferasas/genética
4.
Brain ; 145(8): 2742-2754, 2022 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-35680425

RESUMEN

Autoantibodies against the extracellular domain of the N-methyl-d-aspartate receptor (NMDAR) NR1 subunit cause a severe and common form of encephalitis. To better understand their generation, we aimed to characterize and identify human germinal centres actively participating in NMDAR-specific autoimmunization by sampling patient blood, CSF, ovarian teratoma tissue and, directly from the putative site of human CNS lymphatic drainage, cervical lymph nodes. From serum, both NR1-IgA and NR1-IgM were detected more frequently in NMDAR-antibody encephalitis patients versus controls (both P < 0.0001). Within patients, ovarian teratoma status was associated with a higher frequency of NR1-IgA positivity in serum (OR = 3.1; P < 0.0001) and CSF (OR = 3.8, P = 0.047), particularly early in disease and before ovarian teratoma resection. Consistent with this immunoglobulin class bias, ovarian teratoma samples showed intratumoral production of both NR1-IgG and NR1-IgA and, by single cell RNA sequencing, contained expanded highly-mutated IgA clones with an ovarian teratoma-restricted B cell population. Multiplex histology suggested tertiary lymphoid architectures in ovarian teratomas with dense B cell foci expressing the germinal centre marker BCL6, CD21+ follicular dendritic cells, and the NR1 subunit, alongside lymphatic vessels and high endothelial vasculature. Cultured teratoma explants and dissociated intratumoral B cells secreted NR1-IgGs in culture. Hence, ovarian teratomas showed structural and functional evidence of NR1-specific germinal centres. On exploring classical secondary lymphoid organs, B cells cultured from cervical lymph nodes of patients with NMDAR-antibody encephalitis produced NR1-IgG in 3/7 cultures, from patients with the highest serum NR1-IgG levels (P < 0.05). By contrast, NR1-IgG secretion was observed neither from cervical lymph nodes in disease controls nor in patients with adequately resected ovarian teratomas. Our multimodal evaluations provide convergent anatomical and functional evidence of NMDAR-autoantibody production from active germinal centres within both intratumoral tertiary lymphoid structures and traditional secondary lymphoid organs, the cervical lymph nodes. Furthermore, we develop a cervical lymph node sampling protocol that can be used to directly explore immune activity in health and disease at this emerging neuroimmune interface.


Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , Vasos Linfáticos , Teratoma , Autoanticuerpos , Femenino , Centro Germinal , Humanos , Inmunoglobulina A , Inmunoglobulina G , Neoplasias Ováricas , Receptores de N-Metil-D-Aspartato
5.
J Immigr Minor Health ; 24(6): 1534-1542, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35233682

RESUMEN

Newly arrived refugees and refugee claimants experience low cervical cancer screening (CCS) rates in Canada. We investigated CCS at a dedicated refugee clinic. We completed a retrospective cohort study among patients at the Mosaic Refugee Health Clinic in Calgary, Canada, between 2011 and 2016. We investigated CCS offers and completion by refugee category. We then used multivariable logistic regression to estimate the association of CCS screening and refugee category, accounting for sociodemographic and clinical factors. We included 812 refugees. Most were married (71%) and had limited English proficiency (57%). Overall, 88% and 77% of patients were offered and completed screening, respectively. Compared to government assisted refugees, privately sponsored refugees completed CCS more often (OR 1.60, 95% CI [1.02-2.49]). A dedicated refugee clinic may provide effective CCS to newly arrived refugees irrespective of refugee category, insurance status or other barriers.


Asunto(s)
Refugiados , Neoplasias del Cuello Uterino , Femenino , Humanos , Detección Precoz del Cáncer , Neoplasias del Cuello Uterino/diagnóstico , Estudios Retrospectivos , Canadá , Atención Primaria de Salud
6.
Cancer Immunol Immunother ; 69(10): 2063-2073, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32447412

RESUMEN

Although metastatic disease is responsible for the majority of cancer deaths, tests of novel immunotherapies in mouse tumour models often focus on primary tumours without determining whether these therapies also target metastatic disease. This study examined the impact of depleting Foxp3+ regulatory T cells (Treg), on lung metastases, using a mouse model of breast cancer. After Treg-depletion, generation of an immune response to the primary tumour was a critical determinant for limiting development of metastasis. Indeed, resection of the primary tumour abrogated any effect of Treg-depletion on metastases. In addition, whilst the immune response, generated by the primary tumour, prevented metastases development, it had little impact on controlling established disease. Collectively, the data indicate that metastatic cells in the lung are not controlled by immune responses induced by the primary tumour. These findings indicate that targeting Tregs alone will not suffice for treating lung metastases.


Asunto(s)
Inmunoterapia/métodos , Neoplasias Pulmonares/inmunología , Depleción Linfocítica/métodos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos T Reguladores/inmunología , Neoplasias de la Mama Triple Negativas/inmunología , Animales , Femenino , Factores de Transcripción Forkhead/metabolismo , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/terapia , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Ratones , Linfocitos T Reguladores/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/terapia
7.
J Mol Diagn ; 22(5): 652-669, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32229180

RESUMEN

Prostate cancer is a significant global health issue, and limitations to current patient management pathways often result in overtreatment or undertreatment. New ways to stratify patients are urgently needed. We conducted a feasibility study of such novel assessments, looking for associations between genomic changes and lymphocyte infiltration. An innovative workflow using an in-house targeted sequencing panel, immune cell profiling using an image analysis pipeline, RNA sequencing, and exome sequencing in select cases was tested. Gene fusions were profiled by RNA sequencing in 27 of 27 cases, and a significantly higher tumor-infiltrating lymphocyte (TIL) count was noted in tumors without a TMPRSS2:ERG fusion compared with those with the fusion (P = 0.01). Although this finding was not replicated in a larger validation set (n = 436) of The Cancer Genome Atlas images, there was a trend in the same direction. Differential expression analysis of TIL-high and TIL-low tumors revealed the enrichment of both innate and adaptive immune response pathways. Mutations in mismatch repair genes (MLH1 and MSH6 mutations in 1 of 27 cases) were identified. We describe a potential immune escape mechanism in TMPRSS2:ERG fusion-positive tumors. Detailed profiling, as shown herein, can provide novel insights into tumor biology. Likely differences with findings with other cohorts are related to methods used to define region of interest, but this warrants further study in a larger cohort.


Asunto(s)
Biomarcadores de Tumor , Proteínas de Fusión Oncogénica/genética , Neoplasias de la Próstata/genética , Serina Endopeptidasas/genética , Fosfatidilinositol 3-Quinasa Clase Ia/genética , ADN Helicasas/genética , Reparación de la Incompatibilidad de ADN , Proteínas de Unión al ADN/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación INDEL , Inmunohistoquímica , Linfocitos/inmunología , Linfocitos/metabolismo , Linfocitos/patología , Masculino , Polimorfismo de Nucleótido Simple , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/patología , Análisis de Secuencia de ARN , Regulador Transcripcional ERG/genética
8.
Rev. Bras. Med. Fam. Comunidade (Online) ; 15(42): 2416-2416, 20200210. tab
Artículo en Inglés | LILACS, Coleciona SUS | ID: biblio-1117126

RESUMEN

Training young doctors in family medicine is challenging in any setting and many variables can influence the success or failure of a residency program. This article is the end result of a collaborative work that started in June 2019 at the WONCA Africa Regional Conference in Kampala, during a workshop lead by the Besrour Centre for Global Family Medicine at the College of Family Physicians of Canada. We present here the perspective of a small group of young African family physicians on the experience of being a resident in family medicine in Africa in 2019, hoping that the picture we depict here helps to promote the necessary improvements in the training programs in Africa for the near future.


Formar novos médicos de família é um desafio em qualquer cenário e muitas variáveis podem influenciar o sucesso ou o fracasso de um programa de residência. Este artigo é o resultado final de um trabalho colaborativo iniciado em junho de 2019, na Conferência Regional WONCA África em Kampala, Uganda, durante um workshop liderado pelo Centro Besrour do Colégio Canadense de Medicina de Família. Apresentamos aqui a perspectiva de um pequeno grupo de jovens médicos de família africanos sobre a experiência de ser residente em medicina de família na África em 2019, esperando que a imagem que representamos aqui ajude a promover as melhorias necessárias nos programas de residência na África em um futuro próximo.


La formación de nuevos médicos de familia es un desafío en cualquier lugar y muchas variables pueden influir en el éxito o el fracaso de un programa de residencia. Este artículo es el resultado final del trabajo colaborativo iniciado en junio de 2019 en la Conferencia Regional de África WONCA en Kampala, Uganda, durante un taller dirigido por el Centro Besrour del Colegio Canadiense de Medicina Familiar. Presentamos aquí la perspectiva de un pequeño grupo de jóvenes médicos de familia africanos sobre la experiencia de ser residente en medicina familiar en África en 2019, con la esperanza de que la imagen que representamos aquí ayude a promover mejoras en los programas de residencia en África en un futuro próximo.


Asunto(s)
Educación Médica , Medicina Familiar y Comunitaria , Internado y Residencia
9.
Cancer Immunol Res ; 8(2): 203-216, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31771983

RESUMEN

Enrichment of CD103+ tumor-infiltrating T lymphocytes (TIL) is associated with improved outcomes in patients. However, the characteristics of human CD103+ cytotoxic CD8+ T cells (CTL) and their role in tumor control remain unclear. We investigated the features and antitumor mechanisms of CD103+ CTLs by assessing T-cell receptor (TCR)-matched CD103+ and CD103- cancer-specific CTL immunity in vitro and its immunophenotype ex vivo Interestingly, we found that differentiated CD103+ cancer-specific CTLs expressed the active form of TGFß1 to continually self-regulate CD103 expression, without relying on external TGFß1-producing cells. The presence of CD103 on CTLs improved TCR antigen sensitivity, which enabled faster cancer recognition and rapid antitumor cytotoxicity. These CD103+ CTLs had elevated energetic potential and faster migration capacity. However, they had increased inhibitory receptor coexpression and elevated T-cell apoptosis following prolonged cancer exposure. Our data provide fundamental insights into the properties of matured human CD103+ cancer-specific CTLs, which could have important implications for future designs of tissue-localized cancer immunotherapy strategies.


Asunto(s)
Antígenos CD/metabolismo , Linfocitos T CD8-positivos/inmunología , Cadenas alfa de Integrinas/metabolismo , Neoplasias Pulmonares/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias/inmunología , Linfocitos T Citotóxicos/inmunología , Antígenos CD/inmunología , Humanos , Inmunofenotipificación/métodos , Cadenas alfa de Integrinas/inmunología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias/metabolismo , Neoplasias/patología , Pronóstico , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Factor de Crecimiento Transformador beta1/inmunología , Factor de Crecimiento Transformador beta1/metabolismo
10.
Cancer Immunol Res ; 5(11): 1005-1015, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28947544

RESUMEN

T-cell infiltration into tumors represents a critical bottleneck for immune-mediated control of cancer. We previously showed that this bottleneck can be overcome by depleting immunosuppressive Foxp3+ regulatory T cells (Tregs), a process that can increase frequencies of tumor-infiltrating lymphocytes through promoting the development of specialized portals for lymphocyte entry, namely high endothelial venules (HEVs). In this paper, we used a carcinogen-induced tumor model that allows for coevolution of the tumor microenvironment and the immune response to demonstrate that Treg depletion not only results in widespread disruption to HEV networks in lymph nodes (LNs) but also activates CD8+ T cells, which then drive intratumoral HEV development. Formation of these vessels contrasts with ontogenic HEV development in LNs in that the process is dependent on the TNF receptor and independent of lymphotoxin ß receptor-mediated signaling. These intratumoral HEVs do not express the chemokine CCL21, revealing a previously undescribed intratumoral blood vessel phenotype. We propose a model where Treg depletion enables a self-amplifying loop of T-cell activation, which promotes HEV development, T-cell infiltration, and ultimately, tumor destruction. The findings point to a need to test for HEV development as part of ongoing clinical studies in patients with cancer. Cancer Immunol Res; 5(11); 1005-15. ©2017 AACR.


Asunto(s)
Neoplasias/inmunología , Linfocitos T Reguladores/inmunología , Animales , Células Dendríticas/inmunología , Endotelio Vascular/inmunología , Depleción Linfocítica , Linfocitos Infiltrantes de Tumor/inmunología , Receptor beta de Linfotoxina/inmunología , Metilcolantreno , Ratones , Neoplasias/inducido químicamente , Receptores del Factor de Necrosis Tumoral/inmunología
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