Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Clin Epigenetics ; 16(1): 25, 2024 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336771

RESUMO

RATIONALE: Cancer of unknown primary (CUP) is a group of rare malignancies with poor prognosis and unidentifiable tissue-of-origin. Distinct DNA methylation patterns in different tissues and cancer types enable the identification of the tissue of origin in CUP patients, which could help risk assessment and guide site-directed therapy. METHODS: Using genome-wide DNA methylation profile datasets from The Cancer Genome Atlas (TCGA) and machine learning methods, we developed a 200-CpG methylation feature classifier for CUP tissue of origin prediction (MFCUP). MFCUP was further validated with public-available methylation array data of 2977 specimens and targeted methylation sequencing of 78 Formalin-fixed paraffin-embedded (FFPE) samples from a single center. RESULTS: MFCUP achieved an accuracy of 97.2% in a validation cohort (n = 5923) representing 25 cancer types. When applied to an Infinium 450 K array dataset (n = 1052) and an Infinium EPIC (850 K) array dataset (n = 1925), MFCUP achieved an overall accuracy of 93.4% and 84.8%, respectively. Based on MFCUP, we established a targeted bisulfite sequencing panel and validated it with FFPE sections from 78 patients of 20 cancer types. This methylation sequencing panel correctly identified tissue of origin in 88.5% (69/78) of samples. We also found that the methylation levels of specific CpGs can distinguish one cancer type from others, indicating their potential as biomarkers for cancer diagnosis and screening. CONCLUSION: Our methylation-based cancer classifier and targeted methylation sequencing panel can predict tissue of origin in diverse cancer types with high accuracy.


Assuntos
Metilação de DNA , Neoplasias Primárias Desconhecidas , Humanos , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/genética , Análise de Sequência de DNA
2.
Ann Diagn Pathol ; 68: 152226, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37995412

RESUMO

BACKGROUND: Sacituzumab govitecan, targeting trophoblast cell-surface antigen 2 (TROP2), is approved for the treatment of triple-negative and hormone receptor-positive/HER2-negative breast cancers. However, detailed studies comparing TROP2 protein expression in the different molecular subtypes of breast cancer are limited, and definitive evidence supporting the use of TROP2 as a biomarker for predicting response to this agent in patients with breast cancer is currently lacking. OBJECTIVE: To compare the expression of TROP2 in the different molecular subtypes of breast cancer. METHODS: Immunohistochemical staining for TROP2 was performed on 94 therapy-naive primary invasive breast carcinomas, including 25 luminal A-like, 25 luminal B-like, 19 HER2-like, and 25 triple-negative tumors. RESULTS: Intermediate to high levels of TROP2 expression were observed in the majority of carcinomas of each molecular subtype, with a wide range of expression in each subtype. Occasional tumors with low or absent TROP2 expression were encountered, including two metaplastic carcinomas which were completely negative for TROP2. CONCLUSIONS: Our observations support the continued investigation of the efficacy of sacituzumab govitecan in all molecular subtypes of breast carcinoma. Furthermore, the observed wide range of expression of TROP2 suggests that TROP2 may have potential utility as a biomarker for predicting responsiveness to sacituzumab govitecan. If this proves to be the case, then immunohistochemical staining for TROP2 would be critical for identifying those patients whose tumors are completely negative for TROP2, since these patients may be least likely or unlikely to respond to this agent, and alternative therapies may be more appropriate in such instances.


Assuntos
Neoplasias da Mama , Carcinoma , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Antígenos de Superfície , Biomarcadores , Neoplasias da Mama/patologia , Carcinoma/patologia , Trofoblastos/metabolismo
3.
J Hepatol ; 80(3): 443-453, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38086446

RESUMO

BACKGROUND & AIMS: The liver is a common site of cancer metastasis, most commonly from colorectal cancer, and primary liver cancers that have metastasized are associated with poor outcomes. The underlying mechanisms by which the liver defends against these processes are largely unknown. Prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) are highly expressed in the liver. They positively regulate each other and their deletion results in primary liver cancer. Here we investigated their roles in primary and secondary liver cancer metastasis. METHODS: We identified common target genes of PHB1 and MAT1A using a metastasis array, and measured promoter activity and transcription factor binding using luciferase reporter assays and chromatin immunoprecipitation, respectively. We examined how PHB1 or MAT1A loss promotes liver cancer metastasis and whether their loss sensitizes to colorectal liver metastasis (CRLM). RESULTS: Matrix metalloproteinase-7 (MMP-7) is a common target of MAT1A and PHB1 and its induction is responsible for increased migration and invasion when MAT1A or PHB1 is silenced. Mechanistically, PHB1 and MAT1A negatively regulate MMP7 promoter activity via an AP-1 site by repressing the MAFG-FOSB complex. Loss of MAT1A or PHB1 also increased MMP-7 in extracellular vesicles, which were internalized by colon and pancreatic cancer cells to enhance their oncogenicity. Low hepatic MAT1A or PHB1 expression sensitized to CRLM, but not if endogenous hepatic MMP-7 was knocked down first, which lowered CD4+ T cells while increasing CD8+ T cells in the tumor microenvironment. Hepatocytes co-cultured with colorectal cancer cells express less MAT1A/PHB1 but more MMP-7. Consistently, CRLM raised distant hepatocytes' MMP-7 expression in mice and humans. CONCLUSION: We have identified a PHB1/MAT1A-MAFG/FOSB-MMP-7 axis that controls primary liver cancer metastasis and sensitization to CRLM. IMPACT AND IMPLICATIONS: Primary and secondary liver cancer metastasis is associated with poor outcomes but whether the liver has underlying defense mechanism(s) against metastasis is unknown. Here we examined the hypothesis that hepatic prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) cooperate to defend the liver against metastasis. Our studies found PHB1 and MAT1A form a complex that suppresses matrix metalloproteinase-7 (MMP-7) at the transcriptional level and loss of either PHB1 or MAT1A sensitizes the liver to metastasis via MMP-7 induction. Strategies that target the PHB1/MAT1A-MMP-7 axis may be a promising approach for the treatment of primary and secondary liver cancer metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Neoplasias Colorretais/genética , Neoplasias Hepáticas/patologia , Metaloproteinase 7 da Matriz/genética , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismo , Proibitinas , Microambiente Tumoral
4.
J Pediatr Endocrinol Metab ; 36(12): 1186-1190, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37979187

RESUMO

OBJECTIVES: Alpha-mannosidosis is a rare genetic lysosomal storage condition leading to the systemic buildup of oligomannoside. Clinical presentation and associated conditions, as well as the full extent of histopathologic changes associated with this disease process, are not fully understood. CASE PRESENTATION: We present the case of an 8-year-1-month old patient with persistent anemia and who was initially diagnosed with Celiac disease before ultimately being diagnosed with alpha-mannosidosis. As part of his diagnostic work-up, duodenal and bone marrow biopsies were examined by pathology. Duodenal biopsies showed foamy plasma cells expanding the lamina propria which triggered a workup for a genetic storage disease; features suggestive of Celiac disease which resolved on gluten-free diet were also noted by pathology. Bone marrow analysis via electron microscopy showed cytoplasmic granules and inclusions in multiple immune cell lines. CONCLUSIONS: Alpha-mannosidosis can occur with Celiac disease and milder forms may only be suspected from incidental pathology findings. The ultrastructural bone marrow findings from this case, the first to be reported from human, show numerous disease-associated changes in multiple immune cell lines whose contribution to disease-associated immunodeficiency is unclear.


Assuntos
Doença Celíaca , Doenças por Armazenamento dos Lisossomos , alfa-Manosidose , Humanos , Lactente , alfa-Manosidose/diagnóstico , alfa-Manosidose/complicações , alfa-Manosidose/genética , Microscopia , Doença Celíaca/complicações , Doenças por Armazenamento dos Lisossomos/diagnóstico
5.
Front Immunol ; 14: 1278383, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928535

RESUMO

The pathogenesis of atherosclerosis is defined by impaired lipid handling by macrophages which increases intracellular lipid accumulation. This dysregulation of macrophages triggers the accumulation of apoptotic cells and chronic inflammation which contributes to disease progression. We previously reported that mice with increased macrophage-specific angiotensin-converting enzyme, termed ACE10/10 mice, resist atherosclerosis in an adeno-associated virus-proprotein convertase subtilisin/kexin type 9 (AAV-PCSK9)-induced model. This is due to increased lipid metabolism by macrophages which contributes to plaque resolution. However, the importance of ACE in peripheral blood monocytes, which are the primary precursors of lesional-infiltrating macrophages, is still unknown in atherosclerosis. Here, we show that the ACE-mediated metabolic phenotype is already triggered in peripheral blood circulating monocytes and that this functional modification is directly transferred to differentiated macrophages in ACE10/10 mice. We found that Ly-6Clo monocytes were increased in atherosclerotic ACE10/10 mice. The monocytes isolated from atherosclerotic ACE10/10 mice showed enhanced lipid metabolism, elevated mitochondrial activity, and increased adenosine triphosphate (ATP) levels which implies that ACE overexpression is already altered in atherosclerosis. Furthermore, we observed increased oxygen consumption (VO2), respiratory exchange ratio (RER), and spontaneous physical activity in ACE10/10 mice compared to WT mice in atherosclerotic conditions, indicating enhanced systemic energy consumption. Thus, ACE overexpression in myeloid lineage cells modifies the metabolic function of peripheral blood circulating monocytes which differentiate to macrophages and protect against atherosclerotic lesion progression due to better lipid metabolism.


Assuntos
Aterosclerose , Pró-Proteína Convertase 9 , Animais , Camundongos , Aterosclerose/patologia , Lipídeos , Células Mieloides/patologia
6.
Adv Anat Pathol ; 30(6): 415-420, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37539688

RESUMO

Fibroepithelial lesions of the breast encompass a broad spectrum of lesions from fibroadenomas and their variants to phyllodes tumors, including their clinical range of benign, borderline, and malignant. Classification of this spectrum of neoplasms has historically and currently been based purely on morphology, although the nomenclature has shifted over the years largely due to the significant histologic overlap that exists primarily within the cellular fibroadenomas to borderline malignant phyllodes tumor categories. A review of the current diagnostic challenge, proposed ancillary studied and their value in prognostic significance, is provided. This article highlights the most recent molecular and genetic findings as well as the limitations of the studies, in the context of practical and available applications for the diagnostician and managerial implications for the clinician.

7.
Front Immunol ; 14: 1178682, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122752

RESUMO

Anaplastic thyroid carcinoma, BRAF non-V600, NRAS, combination immunotherapy and targeted therapy, case report. Anaplastic thyroid carcinoma (ATC) is a rare type of thyroid cancer with a mortality rate near 100%. BRAF V600 and NRAS mutations are the most common drivers of ATC. While patients with BRAF V600-mutated ATC can be treated with BRAF-targeted therapy, there is no effective treatment for ATC driven by NRAS or non-V600 BRAF mutations. For patients with untargetable driver mutations, immunotherapy provides an alternative treatment option. Here, we present a metastatic ATC patient with PD-L1 positive (tumor proportion score of 60%) tumor and NRAS Q61R/BRAF D594N mutations, who progressed on PD-1 antibody sintilimab plus angiogenesis inhibitor anlotinib. The class 3 BRAF mutant D594N is sensitive to the inhibition of MEK inhibitor trametinib, and its oncogenic activity also depends on CRAF, which can be inhibited by BRAF inhibitor dabrafenib. For these reasons, the patient received a salvage treatment regime of dabrafenib, trametinib, and sintilimab, which resulted in a complete pathological response. To our best knowledge, this is the first report of successful treatment of ATC patients with concurrent NRAS/BRAF non-V600 mutations with the combination of immunotherapy and targeted therapy. Further investigation is required to decipher the mechanism by which the combination of dabrafenib/trametinib with PD-1 antibody overcomes initial immunotherapy resistance likely mediated by concurrent BRAF and NRAS mutations.


Assuntos
Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Receptor de Morte Celular Programada 1/genética , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Mutação , Proteínas de Membrana/genética , GTP Fosfo-Hidrolases/genética
8.
Int J Mol Sci ; 24(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37240386

RESUMO

Fibroepithelial lesions of the breast (FELs) are a heterogeneous group of neoplasms exhibiting a histologic spectrum ranging from fibroadenomas (FAs) to malignant phyllodes tumors (PTs). Despite published histologic criteria for their classification, it is common for such lesions to exhibit overlapping features, leading to subjective interpretation and interobserver disagreements in histologic diagnosis. Therefore, there is a need for a more objective diagnostic modality to aid in the accurate classification of these lesions and to guide appropriate clinical management. In this study, the expression of 750 tumor-related genes was measured in a cohort of 34 FELs (5 FAs, 9 cellular FAs, 9 benign PTs, 7 borderline PTs, and 4 malignant PTs). Differentially expressed gene analysis, gene set analysis, pathway analysis, and cell type analysis were performed. Genes involved in matrix remodeling and metastasis (e.g., MMP9, SPP1, COL11A1), angiogenesis (VEGFA, ITGAV, NFIL3, FDFR1, CCND2), hypoxia (ENO1, HK1, CYBB, HK2), metabolic stress (e.g., UBE2C, CDKN2A, FBP1), cell proliferation (e.g., CENPF, CCNB1), and the PI3K-Akt pathway (e.g., ITGB3, NRAS) were highly expressed in malignant PTs and less expressed in borderline PTs, benign PTs, cellular FAs, and FAs. The overall gene expression profiles of benign PTs, cellular FAs, and FAs were very similar. Although a slight difference was observed between borderline and benign PTs, a higher degree of difference was observed between borderline and malignant PTs. Additionally, the macrophage cell abundance scores and CCL5 were significantly higher in malignant PTs compared with all other groups. Our results suggest that the gene-expression-profiling-based approach could lead to further stratification of FELs and may provide clinically useful biological and pathophysiological information to improve the existing histologic diagnostic algorithm.


Assuntos
Neoplasias da Mama , Fibroadenoma , Tumor Filoide , Humanos , Feminino , Fosfatidilinositol 3-Quinases/genética , Mama/patologia , Neoplasias da Mama/patologia , Tumor Filoide/genética , Tumor Filoide/diagnóstico , Tumor Filoide/patologia , Fibroadenoma/genética , Fibroadenoma/patologia , Perfilação da Expressão Gênica
9.
Cardiovasc Res ; 119(9): 1825-1841, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37225143

RESUMO

AIMS: The metabolic failure of macrophages to adequately process lipid is central to the aetiology of atherosclerosis. Here, we examine the role of macrophage angiotensin-converting enzyme (ACE) in a mouse model of PCSK9-induced atherosclerosis. METHODS AND RESULTS: Atherosclerosis in mice was induced with AAV-PCSK9 and a high-fat diet. Animals with increased macrophage ACE (ACE 10/10 mice) have a marked reduction in atherosclerosis vs. WT mice. Macrophages from both the aorta and peritoneum of ACE 10/10 express increased PPARα and have a profoundly altered phenotype to process lipids characterized by higher levels of the surface scavenger receptor CD36, increased uptake of lipid, increased capacity to transport long chain fatty acids into mitochondria, higher oxidative metabolism and lipid ß-oxidation as determined using 13C isotope tracing, increased cell ATP, increased capacity for efferocytosis, increased concentrations of the lipid transporters ABCA1 and ABCG1, and increased cholesterol efflux. These effects are mostly independent of angiotensin II. Human THP-1 cells, when modified to express more ACE, increase expression of PPARα, increase cell ATP and acetyl-CoA, and increase cell efferocytosis. CONCLUSION: Increased macrophage ACE expression enhances macrophage lipid metabolism, cholesterol efflux, efferocytosis, and it reduces atherosclerosis. This has implications for the treatment of cardiovascular disease with angiotensin II receptor antagonists vs. ACE inhibitors.


Assuntos
Aterosclerose , Pró-Proteína Convertase 9 , Humanos , Animais , Camundongos , Pró-Proteína Convertase 9/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Metabolismo dos Lipídeos , Colesterol/metabolismo , Macrófagos/metabolismo , Aterosclerose/genética , Aterosclerose/prevenção & controle , Angiotensinas/metabolismo , Trifosfato de Adenosina/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo
10.
Cancer Med ; 12(10): 11672-11685, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36999792

RESUMO

BACKGROUND: Approximately 90% of pancreatic ductal adenocarcinoma (PDAC) cases are driven by the untargetable non-G12C KRAS mutations, and only a small subset of patients are eligible for FDA-approved precision therapies. The practice of precision therapy in pancreatic cancer was limited by the paucity of targetable genetic alterations, especially in the Asian population. METHODS: To explore therapeutic targets in 499 Chinese PDAC patients, a deep sequencing panel (OncoPanscan™, Genetron health) was used to characterize somatic alterations including point mutations, indels, copy number alterations, gene fusions as well as pathogenic germline variants. RESULTS: We performed genomic profiling in 499 Chinese PDAC patients, which revealed somatic driver mutations in KRAS, TP53, CDKN2A, SMAD4, ARID1A, RNF43, and pathogenic germline variants (PGVs) in cancer predisposition genes including BRCA2, PALB2, and ATM. Overall, 20.4% of patients had targetable genomic alterations. About 8.4% of patients carried inactivating germline and somatic variants in BRCA1/2 and PALB2, which were susceptible to platinum and PARP inhibitors therapy. Patients with KRAS wild-type disease and early-onset pancreatic cancer (EOPC) harbored actionable mutations including BRAF, EGFR, ERBB2, and MAP2K1/2. Compared to PGV-negative patients, PGV-positive patients were younger and more likely to have a family history of cancer. Furthermore, PGVs in PALB2, BRCA2, and ATM were associated with high PDAC risk in the Chinese population. CONCLUSIONS: Our results demonstrated that a genetic screen of actionable genomic variants could facilitate precision therapy and cancer risk reduction in pancreatic cancer patients of Asian ethnicity.


Assuntos
Carcinoma Ductal Pancreático , População do Leste Asiático , Neoplasias Pancreáticas , Humanos , Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , População do Leste Asiático/genética , Genômica , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/epidemiologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Pancreáticas
11.
Front Physiol ; 14: 1151908, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969603

RESUMO

Angiotensin-converting enzyme (ACE) is canonically known for its role in the renin-angiotensin system (RAS) where its conversion of angiotensin I (Ang I) to the bioactive peptide angiotensin II (Ang II) helps to regulate blood pressure, electrolyte, and volume homeostasis. Further studies on ACE have shown that its enzymatic activity is relatively non-specific and functions outside of the RAS axis. Of the multiple systems it has been implicated in, ACE has been found to play an important role in the development and modulation of hematopoiesis and the immune system, both through the RAS and independently of the RAS axis.

12.
J Cancer Res Clin Oncol ; 149(9): 6139-6150, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36680582

RESUMO

PURPOSE: Small bowel carcinoma (SBA) is a rare gastrointestinal cancer with a poor prognosis. Recent genomic profiling studies revealed that the landscape of molecular alterations in SBA was distinct from colorectal cancer (CRC) and gastric cancer (GC). To explore driver and targetable alterations in SBA, we performed next-generation sequencing in 107 Chinese SBA patients. METHODS: DNA from paraffin-embedded SBA samples and the corresponding peripheral blood control samples were analyzed through a next-generation sequencing panel. Somatic alterations including point mutations, indels, copy number alterations, gene fusions as well as pathogenic germline variants were characterized. RESULTS: More than half of SBA cases carried KRAS mutations, including canonical (G12, G12, Q61) and atypical mutations (A146, L19, and K117). To our best knowledge, this was the first report of rare driver alterations including KRAS A146V/L19F, PIK3CA N345K/G364R/Q546E, and ZKSCAN1-MET fusion in SBA. Compared to KRAS-mutant patients, alternative activating alterations were enriched in KRAS wild-type patients, and some of them are targetable. Among BRAF-mutated SBA patients, class 1/2 BRAF mutants were mutually exclusive with RAS mutations, but class 3 BRAF mutants were not. Activating ERBB2 alternations, including amplification and activating mutations, represent the most common targetable alternation in this SBA cohort. Of note, the spectrums of BRAF and PIK3CA mutations in this Chinese SBA cohort were distinct from those of a European SBA cohort. Patients with three druggable mutations (PIK3CA, MAP2K1, KRAS G12C) had a high prevalence of concurring drivers, which may interfere with the clinical efficacy of single-target therapy. CONCLUSION: Taken together, our work provided a comprehensive analysis of driver and targetable alterations in SBA, which can facilitate the practice of precision oncology in this challenging disease.


Assuntos
Carcinoma , Neoplasias Colorretais , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , População do Leste Asiático , Proteínas Proto-Oncogênicas p21(ras)/genética , Medicina de Precisão , Mutação , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/genética
13.
Pathogens ; 11(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36364996

RESUMO

Dynamic post-translational modifications allow the rapid, specific, and tunable regulation of protein functions in eukaryotic cells. S-acylation is the only reversible lipid modification of proteins, in which a fatty acid, usually palmitate, is covalently attached to a cysteine residue of a protein by a zDHHC palmitoyl acyltransferase enzyme. Depalmitoylation is required for acylation homeostasis and is catalyzed by an enzyme from the alpha/beta hydrolase family of proteins usually acyl-protein thioesterase (APT1). The enzyme responsible for depalmitoylation in Trypanosoma brucei parasites is currently unknown. We demonstrate depalmitoylation activity in live bloodstream and procyclic form trypanosomes sensitive to dose-dependent inhibition with the depalmitoylation inhibitor, palmostatin B. We identified a homologue of human APT1 in Trypanosoma brucei which we named TbAPT-like (TbAPT-L). Epitope-tagging of TbAPT-L at N- and C- termini indicated a cytoplasmic localization. Knockdown or over-expression of TbAPT-L in bloodstream forms led to robust changes in TbAPT-L mRNA and protein expression but had no effect on parasite growth in vitro, or cellular depalmitoylation activity. Esterase activity in cell lysates was also unchanged when TbAPT-L was modulated. Unexpectedly, recombinant TbAPT-L possesses esterase activity with specificity for short- and medium-chain fatty acid substrates, leading to the conclusion, TbAPT-L is a lipase, not a depalmitoylase.

14.
Biosci Microbiota Food Health ; 41(4): 185-194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36258765

RESUMO

Creatine is an organic compound which is utilized in biological activities, especially for adenosine triphosphate (ATP) production in the phosphocreatine system. This is a well-known biochemical reaction that is generally recognized as being mainly driven in specific parts of the body, such as the skeletal muscle and brain. However, our report shows a novel aspect of creatine utilization and ATP synthesis in innate immune cells. Creatine supplementation enhanced immune responses in neutrophils, such as cytokine production, reactive oxygen species (ROS) production, phagocytosis, and NETosis, which were characterized as antibacterial activities. This creatine-induced functional upregulation of neutrophils provided a protective effect in a murine bacterial sepsis model. The mortality rate in mice challenged with Escherichia coli K-12 was decreased by creatine supplementation compared with the control treatment. Corresponding to this decrease in mortality, we found that creatine supplementation decreased blood pro-inflammatory cytokine levels and bacterial colonization in organs. Creatine supplementation significantly increased the cellular ATP level in neutrophils compared with the control treatment. This ATP increase was due to the phosphocreatine system in the creatine-treated neutrophils. In addition, extracellular creatine was used in this ATP synthesis, as inhibition of creatine uptake abolished the increase in ATP in the creatine-treated neutrophils. Thus, creatine is an effective nutrient for modifying the immunological function of neutrophils, which contributes to enhancement of antibacterial immunity.

15.
Front Cell Infect Microbiol ; 12: 1000972, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189341

RESUMO

Nanotechnology is revolutionizing many sectors of science, from food preservation to healthcare to energy applications. Since 1995, when the first nanomedicines started being commercialized, drug developers have relied on nanotechnology to improve the pharmacokinetic properties of bioactive molecules. The development of advanced nanomaterials has greatly enhanced drug discovery through improved pharmacotherapeutic effects and reduction of toxicity and side effects. Therefore, highly toxic treatments such as cancer chemotherapy, have benefited from nanotechnology. Considering the toxicity of the few therapeutic options to treat neglected tropical diseases, such as leishmaniasis and Chagas disease, nanotechnology has also been explored as a potential innovation to treat these diseases. However, despite the significant research progress over the years, the benefits of nanotechnology for both diseases are still limited to preliminary animal studies, raising the question about the clinical utility of nanomedicines in this field. From this perspective, this review aims to discuss recent nanotechnological developments, the advantages of nanoformulations over current leishmanicidal and trypanocidal drugs, limitations of nano-based drugs, and research gaps that still must be filled to make these novel drug delivery systems a reality for leishmaniasis and Chagas disease treatment.


Assuntos
Doença de Chagas , Leishmaniose , Tripanossomicidas , Animais , Doença de Chagas/tratamento farmacológico , Leishmaniose/tratamento farmacológico , Nanotecnologia , Doenças Negligenciadas/tratamento farmacológico , Tripanossomicidas/uso terapêutico
16.
Front Oncol ; 11: 738832, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926253

RESUMO

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the standard of care for advanced non-small-cell lung cancer (NSCLC) patients. However, most patients will eventually develop resistance. For EGFR-TKI resistance mediated by MET amplification, the combination of EGFR and MET TKIs has shown promising results in early clinical trials. However, acquired resistance to MET inhibitors forms a formidable challenge to this dual blockade approach. Here, we presented an NSCLC patient with EGFR exon 19 deletion (ex19del) who was resistant to first-line erlotinib treatment but responded to chemotherapy. Given the finding of MET overexpression/amplification after disease progression, the patient received gefitinib plus crizotinib with a partial response. Her disease progressed again, and molecular testing revealed a novel MET Y1230H mutation and a PD-L1 TPS score of 75%. She received a salvage regime consisting of gefitinib, cabozantinib, and pembrolizumab with a partial response. Since we now know that EGFR ex19del NSCLC patients generally do not respond to PD-1 blockade therapy, this response is more likely the contribution from gefitinib plus cabozantinib. Therefore, sequential use of type I and II MET inhibitors in EGFR/MET dual blockade may be an effective therapeutic option for EGFR-mutant, MET-amplified NSCLC.

17.
Front Cell Infect Microbiol ; 11: 657257, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34476220

RESUMO

T. cruzi, the causal agent of Chagas disease, is a parasite able to infect different types of host cells and to persist chronically in the tissues of human and animal hosts. These qualities and the lack of an effective treatment for the chronic stage of the disease have contributed to the durability and the spread of the disease around the world. There is an urgent necessity to find new therapies for Chagas disease. Drug repurposing is a promising and cost-saving strategy for finding new drugs for different illnesses. In this work we describe the effect of carvedilol on T. cruzi. This compound, selected by virtual screening, increased the accumulation of immature autophagosomes characterized by lower acidity and hydrolytic properties. As a consequence of this action, the survival of trypomastigotes and the replication of epimastigotes and amastigotes were impaired, resulting in a significant reduction of infection and parasite load. Furthermore, carvedilol reduced the whole-body parasite burden peak in infected mice. In summary, in this work we present a repurposed drug with a significant in vitro and in vivo activity against T. cruzi. These data in addition to other pharmacological properties make carvedilol an attractive lead for Chagas disease treatment.


Assuntos
Parasitos , Trypanosoma cruzi , Animais , Autofagia , Carvedilol/farmacologia , Reposicionamento de Medicamentos , Camundongos
18.
JCI Insight ; 6(9)2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33986194

RESUMO

Chagas disease is caused by infection with the protozoan parasite Trypanosoma cruzi (T. cruzi), an intracellular pathogen that causes significant morbidity and death among millions in the Americas from Canada to Argentina. Current therapy involves oral administration of the nitroimidazole benznidazole (BNZ), which has serious side effects that often necessitate cessation of treatment. To both avoid off-target side effects and reduce the necessary dosage of BNZ, we packaged the drug within poly(ethylene glycol)-block-poly(propylene sulfide) polymersomes (BNZ-PSs). We show that these vesicular nanocarriers enhanced intracellular delivery to phagocytic cells and tested this formulation in a mouse model of T. cruzi infection. BNZ-PS is not only nontoxic but also significantly more potent than free BNZ, effectively reducing parasitemia, intracellular infection, and tissue parasitosis at a 466-fold lower dose of BNZ. We conclude that BNZ-PS was superior to BNZ for treatment of T. cruzi infection in mice and that further modifications of this nanocarrier formulation could lead to a wide range of custom controlled delivery applications for improved treatment of Chagas disease in humans.


Assuntos
Doença de Chagas/tratamento farmacológico , Sistemas de Liberação de Fármacos por Nanopartículas , Nitroimidazóis/administração & dosagem , Fagócitos/parasitologia , Tripanossomicidas/administração & dosagem , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Portadores de Fármacos , Camundongos , Nitroimidazóis/farmacologia , Fagócitos/efeitos dos fármacos , Polietilenoglicóis , Sulfetos , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos
19.
Front Genet ; 12: 799807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35116055

RESUMO

Lynch syndrome (LS) is a cancer-predisposing genetic disease mediated by pathogenic mutations in DNA mismatch repair (MMR) genes MLH1, MSH2, MSH6, and PMS2. Accumulating evidence demonstrates that there is significant biological heterogeneity across MMR genes. Compared to MLH1 and MSH2, PMS2 variant carriers have a much lower risk for LS-related cancers. Tumors in MLH1 and MSH2 variant carriers often display MMR deficiency (dMMR) and/or high microsatellite instability (MSI-H), two predictive biomarkers for immunotherapy efficacy. However, tumors in PMS2 variant carriers are largely microsatellite stable (MSS) instead of MSI. Therefore, the optimal management of cancer patients with LS requires the integration of disease stage, MMR gene penetrance, dMMR/MSI status, and tumor mutational burden (TMB). In this work, we presented a locally advanced lung cancer patient with dMMR/MSI-H/TMB-H tumor and selective loss of PMS2 by immunohistochemistry. Germline testing revealed a rare PMS2 splicing variant (c.1144+1G>A) in the proband and his healthy daughter. The diagnosis of LS was made based on genetic analysis of this variant and literature review. Given the incomplete penetrance of PMS2, the proband and the carrier received tailored genetic counseling. To reduce cancer risk, the proband received four cycles of nivolumab plus chemotherapy and achieved a disease-free survival of sixteen months.

20.
Front Immunol ; 12: 784861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069555

RESUMO

HER2 amplification/overexpression is a common driver in a variety of cancers including gallbladder cancer (GBC). For patients with metastatic GBC, chemotherapy remains the standard of care with limited efficacy. The combination of HER2 antibody trastuzumab plus chemotherapy is the frontline treatment option for patients with HER2-positive breast cancer and gastric cancer. Recently, this regime also showed antitumor activity in HER2-positive GBC. However, resistance to this regime represents a clinical challenge. Camrelizumab is a novel PD-1 antibody approved for Hodgkin lymphoma and hepatocellular carcinoma in China. In this study, we presented a HER2-positive metastatic GBC patient who was refractory to trastuzumab plus chemotherapy but experienced significant clinical benefit after the addition of camrelizumab. Our case highlights the potential of immunotherapy in combination with HER2-targeted therapy in HER2-positive GBC. We also demonstrated that two immune-related adverse events (irAEs) associated with camrelizumab can be managed with an anti-VEGF agent apatinib. This case not only highlights the importance of irAE management in patients treated with camrelizumab, but also demonstrates the potential of PD-1 antibody plus trastuzumab in HER2-positive GBC patients who have developed resistance to chemotherapy and trastuzumab-based targeted therapy.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias da Vesícula Biliar , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/administração & dosagem , Idoso , Neoplasias da Vesícula Biliar/tratamento farmacológico , Neoplasias da Vesícula Biliar/enzimologia , Neoplasias da Vesícula Biliar/patologia , Humanos , Masculino , Metástase Neoplásica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...