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1.
Cell ; 187(5): 1255-1277.e27, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38359819

RESUMO

Despite the successes of immunotherapy in cancer treatment over recent decades, less than <10%-20% cancer cases have demonstrated durable responses from immune checkpoint blockade. To enhance the efficacy of immunotherapies, combination therapies suppressing multiple immune evasion mechanisms are increasingly contemplated. To better understand immune cell surveillance and diverse immune evasion responses in tumor tissues, we comprehensively characterized the immune landscape of more than 1,000 tumors across ten different cancers using CPTAC pan-cancer proteogenomic data. We identified seven distinct immune subtypes based on integrative learning of cell type compositions and pathway activities. We then thoroughly categorized unique genomic, epigenetic, transcriptomic, and proteomic changes associated with each subtype. Further leveraging the deep phosphoproteomic data, we studied kinase activities in different immune subtypes, which revealed potential subtype-specific therapeutic targets. Insights from this work will facilitate the development of future immunotherapy strategies and enhance precision targeting with existing agents.


Assuntos
Neoplasias , Proteogenômica , Humanos , Terapia Combinada , Genômica , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Proteômica , Evasão Tumoral
2.
Cell ; 184(16): 4348-4371.e40, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34358469

RESUMO

Lung squamous cell carcinoma (LSCC) remains a leading cause of cancer death with few therapeutic options. We characterized the proteogenomic landscape of LSCC, providing a deeper exposition of LSCC biology with potential therapeutic implications. We identify NSD3 as an alternative driver in FGFR1-amplified tumors and low-p63 tumors overexpressing the therapeutic target survivin. SOX2 is considered undruggable, but our analyses provide rationale for exploring chromatin modifiers such as LSD1 and EZH2 to target SOX2-overexpressing tumors. Our data support complex regulation of metabolic pathways by crosstalk between post-translational modifications including ubiquitylation. Numerous immune-related proteogenomic observations suggest directions for further investigation. Proteogenomic dissection of CDKN2A mutations argue for more nuanced assessment of RB1 protein expression and phosphorylation before declaring CDK4/6 inhibition unsuccessful. Finally, triangulation between LSCC, LUAD, and HNSCC identified both unique and common therapeutic vulnerabilities. These observations and proteogenomics data resources may guide research into the biology and treatment of LSCC.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Pulmonares/genética , Proteogenômica , Acetilação , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Proteínas de Neoplasias/metabolismo , Fosforilação , Ligação Proteica , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Ubiquitinação
3.
Mol Cell ; 71(6): 897-910.e8, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30122534

RESUMO

Chromatin ubiquitination by the ubiquitin ligase RNF168 is critical to regulate the DNA damage response (DDR). DDR deficiencies lead to cancer-prone syndromes, but whether this reflects DNA repair defects is still elusive. We identified key factors of the RNF168 pathway as essential mediators of efficient DNA replication in unperturbed S phase. We found that loss of RNF168 leads to reduced replication fork progression and to reversed fork accumulation, particularly evident at repetitive sequences stalling replication. Slow fork progression depends on MRE11-dependent degradation of reversed forks, implicating RNF168 in reversed fork protection and restart. Consistent with regular nucleosomal organization of reversed forks, the replication function of RNF168 requires H2A ubiquitination. As this novel function is shared with the key DDR players ATM, γH2A.X, RNF8, and 53BP1, we propose that double-stranded ends at reversed forks engage classical DDR factors, suggesting an alternative function of this pathway in preventing genome instability and human disease.


Assuntos
Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Histonas/metabolismo , Linhagem Celular , Quebras de DNA de Cadeia Dupla , Replicação do DNA/fisiologia , Proteínas de Ligação a DNA/metabolismo , Humanos , Fase S/fisiologia , Transdução de Sinais , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia
4.
Mol Cell ; 67(5): 882-890.e5, 2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28886337

RESUMO

DNA damage tolerance during eukaryotic replication is orchestrated by PCNA ubiquitination. While monoubiquitination activates mutagenic translesion synthesis, polyubiquitination activates an error-free pathway, elusive in mammals, enabling damage bypass by template switching. Fork reversal is driven in vitro by multiple enzymes, including the DNA translocase ZRANB3, shown to bind polyubiquitinated PCNA. However, whether this interaction promotes fork remodeling and template switching in vivo was unknown. Here we show that damage-induced fork reversal in mammalian cells requires PCNA ubiquitination, UBC13, and K63-linked polyubiquitin chains, previously involved in error-free damage tolerance. Fork reversal in vivo also requires ZRANB3 translocase activity and its interaction with polyubiquitinated PCNA, pinpointing ZRANB3 as a key effector of error-free DNA damage tolerance. Mutations affecting fork reversal also induced unrestrained fork progression and chromosomal breakage, suggesting fork remodeling as a global fork slowing and protection mechanism. Targeting these fork protection systems represents a promising strategy to potentiate cancer chemotherapy.


Assuntos
Dano ao DNA , DNA Helicases/metabolismo , Replicação do DNA , DNA de Neoplasias/biossíntese , Neoplasias/enzimologia , Poliubiquitina/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Origem de Replicação , Animais , Sistemas CRISPR-Cas , DNA Helicases/genética , DNA de Neoplasias/genética , DNA de Neoplasias/ultraestrutura , Células HCT116 , Células HEK293 , Humanos , Cinética , Camundongos , Mutação , Neoplasias/genética , Neoplasias/ultraestrutura , Antígeno Nuclear de Célula em Proliferação/genética , Interferência de RNA , Transfecção , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitinação
5.
Br J Cancer ; 131(1): 171-183, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38760444

RESUMO

BACKGROUND: Risk of recurrence and progression of ductal carcinoma in situ (DCIS) to invasive cancer remains uncertain, emphasizing the need for developing predictive biomarkers of aggressive DCIS. METHODS: Human cell lines and mouse models of disease progression were analyzed for candidate risk predictive biomarkers identified and validated in two independent DCIS cohorts. RESULTS: RNA profiling of normal mammary and DCIS tissues (n = 48) revealed that elevated SOX11 expression correlates with MKI67, EZH2, and DCIS recurrence score. The 21T human cell line model of DCIS progression to invasive cancer and two mouse models developing mammary intraepithelial neoplasia confirmed the findings. AKT activation correlated with chromatin accessibility and EZH2 enrichment upregulating SOX11 expression. AKT and HER2 inhibitors decreased SOX11 expression along with diminished mammosphere formation. SOX11 was upregulated in HER2+ and basal-like subtypes (P < 0.001). Longitudinal DCIS cohort (n = 194) revealed shorter recurrence-free survival in SOX11+ than SOX11- patients (P = 0.0056 in all DCIS; P < 0.0001 in HER2+ subtype) associated with increased risk of ipsilateral breast event/IBE (HR = 1.9, 95%CI = 1.2-2.9; P = 0.003). DISCUSSION: Epigenetic activation of SOX11 drives recurrence of DCIS and progression to invasive cancer, suggesting SOX11 as a predictive biomarker of IBE.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Progressão da Doença , Epigênese Genética , Recidiva Local de Neoplasia , Fatores de Transcrição SOXC , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Animais , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/metabolismo , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Camundongos , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Linhagem Celular Tumoral , Invasividade Neoplásica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo
6.
Histopathology ; 85(3): 503-509, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38973399

RESUMO

BACKGROUND: Adenoid cystic carcinoma is a rare subtype of triple-negative breast carcinoma. These low-grade tumours, which are treated by simple mastectomy and have an excellent prognosis compared to other triple-negative breast carcinomas. Solid-variant adenoid cystic carcinomas have basaloid features and are difficult to distinguish morphologically from other triple-negative breast cancers. Breast adenoid cystic carcinoma exhibits MYB protein overexpression, which can be detected by immunohistochemistry (IHC). AIM: We compared the IHC expression of MYB in solid-variant adenoid cystic carcinoma with that in other triple-negative breast cancers. METHODS: We conducted IHC staining of 210 samples of triple-negative breast cancers, including solid-variant adenoid cystic carcinoma (n = 17), metaplastic breast carcinoma (n = 44), basaloid triple-negative breast cancer (n = 21), and other triple-negative invasive ductal carcinoma (n = 128). We classified nuclear staining of MYB as diffuse/strong (3+), focal moderate (2+), focal weak (1+), or none (0). RESULTS: All 17 solid/basaloid adenoid cystic carcinoma cases exhibited 3+ MYB expression. Of the 21 solid/basaloid triple-negative breast cancers, one (5%) had 2+ expression, seven (33%) 1+ expression, and 13 (62%) 0 expression. Of the 44 metaplastic carcinoma cases, 39 cases (89%) had no (0) staining, and the other five cases had focal weak (1+) or moderate (2+) staining. Among the 128 triple-negative invasive ductal carcinoma cases, 92 cases (72%) had no (0) staining, 36 cases (28%) exhibited focal weak (1+) or moderate (2+) staining. CONCLUSIONS: Our study revealed diffuse/strong MYB staining (3+) only in solid/basaloid adenoid cystic carcinomas. Thus, we recommend routine MYB IHC staining in triple-negative breast carcinoma with solid/basaloid morphology to improve diagnostic accuracy.


Assuntos
Biomarcadores Tumorais , Carcinoma Adenoide Cístico , Imuno-Histoquímica , Proteínas Proto-Oncogênicas c-myb , Neoplasias de Mama Triplo Negativas , Humanos , Carcinoma Adenoide Cístico/metabolismo , Carcinoma Adenoide Cístico/diagnóstico , Carcinoma Adenoide Cístico/patologia , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/diagnóstico , Feminino , Proteínas Proto-Oncogênicas c-myb/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Pessoa de Meia-Idade , Idoso , Adulto , Sensibilidade e Especificidade , Idoso de 80 Anos ou mais
7.
Neurol Sci ; 44(9): 3107-3122, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37087504

RESUMO

BACKGROUND: The principal conditions differentiating disorders of consciousness (DOC) patients are the unresponsive wakefulness syndrome/vegetative state (UWS/VS) and the minimally conscious state (MCS). Many individuals who suffer from sudden-onset severe brain injury move through stages of UWS/VS and MCS before regaining full awareness. In some patients, the DOC condition is protracted for years (PDOC). In this study, we observed PDOC patients for 6 months to assess possible changes in their level of consciousness. METHODS: We enrolled 40 PDOC patients, 23 UWS/VS and 17 MCS hosted in a dedicated unit for long-term brain injury care. The time from injury was 472 ± 533 days for UWS/VS and 1090 ± 1079 days for MCS. The Wessex Head Injury Matrix (WHIM), Coma Recovery Scale-R (CRS-R), and Nociception Coma Scale were administered monthly for 6 months. RESULTS: During the period of assessment, the percentage of UWS/VS shifted from 58 to 45%, while for the MCS, from 42 to 55%. A positive correlation was found for the UWS/VS patients between the months of observation with the CRS-R total score and WHIM total numbers of behaviors (TNB). In the UWS/VS group, the CRS-R auditive and visual subscales correlated positively with the observation time. During the whole period of observation, 8 patients had constant CRS-R total scores while the WHIM TNB changed in 7 of them. CONCLUSION: Our findings demonstrated that the monthly assessment of PDOC by means of the CRS-R and WHIM was able to detect also subtle changes in consciousness level.


Assuntos
Lesões Encefálicas , Traumatismos Craniocerebrais , Humanos , Estado de Consciência/fisiologia , Coma , Transtornos da Consciência/diagnóstico , Lesões Encefálicas/diagnóstico , Vigília , Estado Vegetativo Persistente/diagnóstico
8.
Int J Mol Sci ; 24(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36902092

RESUMO

Shigellosis causes more than 200,000 deaths worldwide and most of this burden falls on Low- and Middle-Income Countries (LMICs), with a particular incidence in children under 5 years of age. In the last decades, Shigella has become even more worrisome because of the onset of antimicrobial-resistant strains (AMR). Indeed, the WHO has listed Shigella as one of the priority pathogens for the development of new interventions. To date, there are no broadly available vaccines against shigellosis, but several candidates are being evaluated in preclinical and clinical studies, bringing to light very important data and information. With the aim to facilitate the understanding of the state-of-the-art of Shigella vaccine development, here we report what is known about Shigella epidemiology and pathogenesis with a focus on virulence factors and potential antigens for vaccine development. We discuss immunity after natural infection and immunization. In addition, we highlight the main characteristics of the different technologies that have been applied for the development of a vaccine with broad protection against Shigella.


Assuntos
Anti-Infecciosos , Disenteria Bacilar , Vacinas contra Shigella , Shigella , Criança , Humanos , Pré-Escolar , Fatores de Virulência
9.
Mod Pathol ; 35(5): 601-608, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34839351

RESUMO

Triple-negative breast cancer (TNBC) with high tumour-infiltrating lymphocytes (TILs) has been associated with a promising prognosis. To better understand the prognostic value of immune cell subtypes in TNBC, we characterised TILs and the interaction between tumour cells and immune cell subtypes. A total of 145 breast cancer tissues were stained by multiplex immunofluorescence (mIF), including panel 1 (PD-L1, PD-1, CD3, CD8, CD68 and CK) and panel 2 (Foxp3, Granzyme B, CD45RO, CD3, CD8 and CK). Phenotypes were analysed and quantified by pathologists using InForm software. We found that in the ER-negative (ER <1% and HER2-negative) group and the ER/PR-low positive (ER 1-9% and HER2-negative) group, 11.2% and 7.1% of patients were PD-L1+ by the tumour cell score, 29.0% and 28.6% were PD-L1+ by the modified immune cell score and 30.8% and 32.1% were PD-L1+ by the combined positive score. We combined ER-negative and ER/PR-low positive cases for the survival analysis since a 10% cut-off is often used in clinical practice for therapeutic purposes. The densities of PD-L1+ tumour cells (HR: 0.366, 95% CI: 0.138-0.970; p = 0.043) within the tumour compartment and CD3+ immune cells in the total area (tumour and stromal compartments combined) (HR: 0.213, 95% CI: 0.070-0.642; p = 0.006) were favourable prognostic biomarkers for overall survival (OS) in TNBC. The density of effector/memory cytotoxic T cells (CD3+CD8+CD45RO+) in the tumour compartment was an independent prognostic biomarker for OS (HR: 0.232, 95% CI: 0.086-0.628; p = 0.004) and DFS (HR: 0.183, 95% CI: 0.1301-0.744; p = 0.009) in TNBC. Interestingly, spatial data suggested that patients with a higher density of PD-L1+ tumour cells had shorter cell-cell distances from tumour cells to cytotoxic T cells (p < 0.01). In conclusion, we found that phenotyping tumour immune cells by mIF is highly informative in understanding the immune microenvironment in TNBC. PD-L1+ tumour cells, total T cells and effector/memory cytotoxic T cells are promising prognostic biomarkers in TNBC.


Assuntos
Memória Imunológica , Neoplasias de Mama Triplo Negativas , Antígeno B7-H1 , Biomarcadores Tumorais , Complexo CD3/imunologia , Linfócitos T CD8-Positivos/patologia , Humanos , Antígenos Comuns de Leucócito/imunologia , Linfócitos do Interstício Tumoral , Prognóstico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral
10.
Am J Respir Crit Care Med ; 203(1): 90-101, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32730093

RESUMO

Rationale: Early pathogenesis of lung adenocarcinoma (LUAD) remains largely unknown. We found that, relative to wild-type littermates, the innate immunomodulator Lcn2 (lipocalin-2) was increased in normal airways from mice with knockout of the airway lineage gene Gprc5a (Gprc5a-/-) and that are prone to developing inflammation and LUAD. Yet, the role of LCN2 in lung inflammation and LUAD is poorly understood.Objectives: Delineate the role of Lcn2 induction in LUAD pathogenesis.Methods: Normal airway brushings, uninvolved lung tissues, and tumors from Gprc5a-/- mice before and after tobacco carcinogen exposure were analyzed by RNA sequencing. LCN2 mRNA was analyzed in public and in-house data sets of LUAD, lung squamous cancer (LUSC), chronic obstructive pulmonary disease (COPD), and LUAD/LUSC with COPD. LCN2 protein was immunohistochemically analyzed in a tissue microarray of 510 tumors. Temporal lung tumor development, gene expression programs, and host immune responses were compared between Gprc5a-/- and Gprc5a-/-/Lcn2-/- littermates.Measurements and Main Results:Lcn2 was progressively elevated during LUAD development and positively correlated with proinflammatory cytokines and inflammation gene sets. LCN2 was distinctively elevated in human LUADs, but not in LUSCs, relative to normal lungs and was associated with COPD among smokers and patients with LUAD. Relative to Gprc5a-/- mice, Gprc5a-/-/Lcn2-/- littermates exhibited significantly increased lung tumor development concomitant with reduced T-cell abundance (CD4+) and richness, attenuated antitumor immune gene programs, and increased immune cell expression of protumor inflammatory cytokines.Conclusions: Augmented LCN2 expression is a molecular feature of COPD-associated LUAD and counteracts LUAD development in vivo by maintaining antitumor immunity.


Assuntos
Adenocarcinoma de Pulmão/imunologia , Antineoplásicos/imunologia , Lipocalina-2/genética , Lipocalina-2/imunologia , Neoplasias Pulmonares/imunologia , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Animais , Biomarcadores/sangue , Feminino , Regulação da Expressão Gênica , Humanos , Lipocalina-2/sangue , Masculino , Camundongos , RNA Mensageiro
11.
Mod Pathol ; 34(4): 710-719, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33011748

RESUMO

Currently there is no highly specific and sensitive marker to identify breast cancer-the most common malignancy in women. Breast cancer can be categorized as estrogen receptor (ER)/progesterone receptor (PR)-positive luminal, human epidermal growth factor receptor 2 (HER2)-positive, or triple-negative breast cancer (TNBC) types based on the expression of ER, PR, and HER2. Although GATA3 is the most widely used tumor marker at present to determine the breast origin, which has been shown to be an excellent marker for ER-positive and low-grade breast cancer, but it does not work well for TNBC with sensitivity as low as <20% in metaplastic breast carcinoma. In the current study, through TCGA data mining we identified trichorhinophalangeal syndrome type 1 (TRPS1) as a specific gene for breast carcinoma across 31 solid tumor types. Moreover, high mRNA level of TRPS1 was found in all four subtypes of breast carcinoma including ER/PR-positive luminal A and B types, HER2-positive type, and basal-type/TNBC. We then analyzed TRPS1 expression in 479 cases of various types of breast cancer using immunochemistry staining, and found that TRPS1 and GATA3 had comparable positive expression in ER-positive (98% vs. 95%) and HER2-positive (87% vs. 88%) breast carcinomas. However, TRPS1 which was highly expressed in TNBC, was significantly higher than GATA3 expression in metaplastic (86% vs. 21%) and nonmetaplastic (86% vs. 51%) TNBC. In addition, TRPS1 expression was evaluated in 1234 cases of solid tumor from different organs. In contrast to the high expression of GATA3 in urothelial carcinoma, TRPS1 showed no or little expression in urothelial carcinomas or in other tumor types including lung adenocarcinoma, pancreatic adenocarcinoma, colon and gastric adenocarcinoma, renal cell carcinoma, melanoma, and ovarian carcinoma. These findings suggest that TRPS1 is a highly sensitive and specific marker for breast carcinoma and can be used as a great diagnostic tool, especially for TNBC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma/química , Imuno-Histoquímica , Proteínas Repressoras/análise , Neoplasias de Mama Triplo Negativas/química , Biomarcadores Tumorais/genética , Carcinoma/genética , Carcinoma/patologia , Bases de Dados Genéticas , Feminino , Fator de Transcrição GATA3/análise , Humanos , Valor Preditivo dos Testes , Proteínas Repressoras/genética , Reprodutibilidade dos Testes , Análise Serial de Tecidos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
12.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919847

RESUMO

Klebsiella pneumoniae (Kp) is an opportunistic pathogen and the leading cause of healthcare-associated infections, mostly affecting subjects with compromised immune systems or suffering from concurrent bacterial infections. However, the dramatic increase in hypervirulent strains and the emergence of new multidrug-resistant clones resulted in Kp occurrence among previously healthy people and in increased morbidity and mortality, including neonatal sepsis and death across low- and middle-income countries. As a consequence, carbapenem-resistant and extended spectrum ß-lactamase-producing Kp have been prioritized as a critical anti-microbial resistance threat by the World Health Organization and this has renewed the interest of the scientific community in developing a vaccine as well as treatments alternative to the now ineffective antibiotics. Capsule polysaccharide is the most important virulence factor of Kp and plays major roles in the pathogenesis but its high variability (more than 100 different types have been reported) makes the identification of a universal treatment or prevention strategy very challenging. However, less variable virulence factors such as the O-Antigen, outer membrane proteins as fimbriae and siderophores might also be key players in the fight against Kp infections. Here, we review elements of the current status of the epidemiology and the molecular pathogenesis of Kp and explore specific bacterial antigens as potential targets for both prophylactic and therapeutic solutions.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/genética , Antibacterianos/efeitos adversos , Carbapenêmicos/efeitos adversos , Carbapenêmicos/uso terapêutico , Humanos , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/genética , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/patogenicidade , beta-Lactamases/efeitos adversos , beta-Lactamases/uso terapêutico
13.
Int J Mol Sci ; 22(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34830042

RESUMO

Shigella is a leading diarrheal cause of morbidity and mortality worldwide, especially in low- and middle-income countries and in children under five years of age. Increasing levels of antimicrobial resistance make vaccine development an even higher global health priority. S. flexneri serotype 6 is one of the targets of many multicomponent vaccines in development to ensure broad protection against Shigella. The O-antigen (OAg) is a key active ingredient and its content is a critical quality attribute for vaccine release in order to monitor their stability and to ensure appropriate immune response. Here, the optimization of two methods to quantify S. flexneri 6 OAg is reported together with the characterization of their performances. The optimized Dische colorimetric method allows a tenfold increment of the sensitivity with respect to the original method and is useful for fast analysis detecting selectively methyl-pentoses, as rhamnose in S. flexneri 6 OAg. Also, a more specific HPAEC-PAD method was developed, detecting the dimer galacturonic acid-galactosamine (GalA-GalN) coming from S. flexneri 6 OAg acid hydrolysis. These methods will facilitate characterization of S. flexneri 6 OAg based vaccines. The colorimetric method can be used for quantification of other polysaccharide containing methyl-pentoses, and the HPAEC-PAD could be extended to other polysaccharides containing uronic acids.


Assuntos
Antígenos O/química , Antígenos O/isolamento & purificação , Shigella flexneri/química , Ácidos Hexurônicos/química , Ácidos Hexurônicos/isolamento & purificação , Pentoses/química , Pentoses/isolamento & purificação
14.
Int J Mol Sci ; 22(3)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525644

RESUMO

Recently, generalized modules for membrane antigens (GMMA) technology has been proposed as an alternative approach to traditional glycoconjugate vaccines for O-antigen delivery. Saccharide length is a well-known parameter that can impact the immune response induced by glycoconjugates both in terms of magnitude and quality. However, the criticality of O-antigen length on the immune response induced by GMMA-based vaccines has not been fully elucidated. Here, Shigella and Salmonella GMMA-producing strains were further mutated in order to display homogeneous polysaccharide populations of different sizes on a GMMA surface. Resulting GMMA were compared in mice immunization studies. Athymic nude mice were also used to investigate the involvement of T-cells in the immune response elicited. In contrast with what has been reported for traditional glycoconjugate vaccines and independent of the pathogen and the sugar structural characteristics, O-antigen length did not result in being a critical parameter for GMMA immunogenicity. This work supports the identification of critical quality attributes to optimize GMMA vaccine design and improve vaccine efficacy and gives insights on the nature of the immune response induced by GMMA.


Assuntos
Vacinas Bacterianas/administração & dosagem , Antígenos O/genética , Salmonella typhimurium/imunologia , Shigella flexneri/imunologia , Shigella sonnei/imunologia , Animais , Anticorpos Antibacterianos/análise , Vacinas Bacterianas/imunologia , Desenho de Fármacos , Engenharia Genética , Imunização , Camundongos , Camundongos Nus , Mutação , Antígenos O/administração & dosagem , Antígenos O/imunologia , Salmonella typhimurium/genética , Soro/imunologia , Shigella flexneri/genética , Shigella sonnei/genética , Linfócitos T/imunologia
15.
Anal Chem ; 92(9): 6304-6311, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32330386

RESUMO

Typhoid fever is a major cause of morbidity and mortality in developing countries. Vaccines based on the Vi capsular polysaccharide are licensed or in development against typhoid fever. Vi content is a critical quality attribute for vaccines release, to monitor their stability and to ensure appropriate immune response. Vi polysaccharide is a homopolymer of α-1,4-N-acetylgalactosaminouronic acid, O-acetylated at the C-3 position, resistant to the commonly used acid hydrolysis for sugar chain depolymerization before monomer quantification. We previously developed a quantification method based on strong alkaline hydrolysis followed by High Performance Anion Exchange Chromatography-Pulsed Amperometric Detection analysis, but with low sensitivity and use for quantification of an unknown product coming from polysaccharide depolymerization. Here we describe the development of a method for Vi polysaccharide quantification based on acid hydrolysis with concomitant use of trifluoroacetic and hydrochloric acids. A Design of Experiment approach was used for the identification of the optimal hydrolysis conditions. The method is 100-fold more sensitive than the previous one, and specifically, resulting in the formation of a known product, confirmed to be the Vi monomer both de-O- and de-N-acetylated by mono- and bidimensional Nuclear Magnetic Resonance spectroscopy and mass spectrometry. Accuracy and precision were determined, and chromatographic conditions were improved to result in reduced time of analysis. This method will facilitate characterization of Vi-based vaccines. Furthermore, a similar approach has the potential to be extended to other polysaccharides containing 2-amino uronic acids, as already verified here for Shigella sonnei O-antigen, Streptococcus pneumoniae serotype 12F, and Staphylococcus aureus types 5 and 8 capsular polysaccharides.


Assuntos
Cromatografia por Troca Iônica/métodos , Polissacarídeos Bacterianos/análise , Ácidos Urônicos/química , Cromatografia Líquida de Alta Pressão , Técnicas Eletroquímicas , Ácido Clorídrico/química , Hidrólise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Polissacarídeos Bacterianos/metabolismo , Reprodutibilidade dos Testes , Ácido Trifluoracético/química , Vacinas Tíficas-Paratíficas/análise , Vacinas Tíficas-Paratíficas/metabolismo
16.
Chemistry ; 25(71): 16277-16287, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31506992

RESUMO

Group B Streptococcus serotypes Ia and Ib capsular polysaccharides are key targets for vaccine development. In spite of their immunospecifity these polysaccharides share high structural similarity. Both are composed of the same monosaccharide residues and differ only in the connection of the Neu5Acα2-3Gal side chain to the GlcNAc unit, which is a ß1-4 linkage in serotype Ia and a ß1-3 linkage in serotype Ib. The development of efficient regioselective routes for GlcNAcß1-3[Glcß1-4]Gal synthons is described, which give access to different group B Streptococcus (GBS) Ia and Ib repeating unit frameshifts. These glycans were used to probe the conformation and molecular dynamics of the two polysaccharides, highlighting the different presentation of the protruding Neu5Acα2-3Gal moieties on the polysaccharide backbones and a higher flexibility of Ib polymer relative to Ia, which can impact epitope exposure.


Assuntos
Cápsulas Bacterianas/química , Polissacarídeos Bacterianos/síntese química , Streptococcus/metabolismo , Cápsulas Bacterianas/metabolismo , Glucosamina/química , Glicosilação , Conformação Molecular , Polissacarídeos Bacterianos/química , Sorogrupo , Estereoisomerismo
17.
J Transl Med ; 13: 305, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26376778

RESUMO

BACKGROUND: The association between malnutrition and worse outcomes as pressure ulcers and mortality is well established in a variety of setting. Currently none investigation was conducted in patients with long-term consequences of the acquired brain injury in which recovery from brain injury could be influenced by secondary complications. The aim of this study was to investigate the association between various nutritional status parameters (in particular albumin) and pressure ulcers formation and short-term mortality in minimal conscious state patients. METHODS: In this prospective, observational study of 5-months duration, a 30 patients sample admitted to a Neurological Institute was considered. All patients underwent a complete medical examination. Anthropometric parameters like mid-arm circumference and mid-arm muscle circumference and nutritional parameters as serum albumin and blood hemoglobin concentration were assessed. RESULTS: At univariate and logistic regression analysis, mid-arm circumference (p = 0.04; beta = -0.89), mid-arm muscle circumference (p = 0.050; beta = -1.29), hemoglobin (p = 0.04, beta -1.1) and albumin (p = 0.04, beta -7.91) were inversely associated with pressure ulcers. The area under the ROC curve for albumin to predict sores was 0.76 (p = 0.02) and mortality was 0.83 (p = 0.03). Patient with lower albumin had significantly higher short-term mortality than those with higher serum albumin (p = 0.03; χ(2) test = 6.47). CONCLUSION: Albumin, haemoglobin and mid-arm circumference are inversely associated with pressure ulcers. Albumin is a prognostic index in MCS patients. Since albumin and haemoglobin could be affected by a variety of factors, this association suggests to optimize nutrition and investigate on other mechanism leading to mortality and pressure ulcers.


Assuntos
Lesões Encefálicas/mortalidade , Estado Nutricional , Úlcera por Pressão/diagnóstico , Úlcera por Pressão/mortalidade , Idoso , Albuminas/metabolismo , Antropometria , Composição Corporal , Lesões Encefálicas/complicações , Estado de Consciência , Feminino , Hemoglobinas/análise , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Úlcera por Pressão/complicações , Estudos Prospectivos , Curva ROC , Albumina Sérica/química , Resultado do Tratamento
18.
Am J Otolaryngol ; 35(1): 62-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24120692

RESUMO

Lidocaine is commonly used for topical anesthesia of the upper airway in patient with anticipated difficult tracheal intubation undergoing awake fiberoptic intubation. Lidocaine toxicity is dose related and proportional to its plasma level. Although neurologic toxicity has been frequently observed with intravenous use, it has also been reported for topical use. We report on a case of a patient with base tongue abscess who developed sudden seizures and coma during application of topical anesthesia with lidocaine for awake fiberoptic intubation. The presence of a deep neck infection that causes hyperemia and edema of the pharyngolaryngeal mucosa may enhance transmucosal systemic absorption of local anesthetic. Moreover, conditions such as hypercarbia, dysphagia, or hepatic diseases are known to facilitate onset of lidocaine neurologic toxicity with serum concentration lower than normal. These findings should be kept in mind before administering topical anesthesia of the upper airway. In the presence of any of these conditions above, either the total dose of local anesthetic or its concentration should be reduced as much as possible.


Assuntos
Abscesso/cirurgia , Anestésicos Locais/efeitos adversos , Intubação Gastrointestinal/métodos , Lidocaína/efeitos adversos , Doenças da Língua/cirurgia , Abscesso/diagnóstico por imagem , Tecnologia de Fibra Óptica , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Doenças da Língua/diagnóstico por imagem
19.
Cancers (Basel) ; 16(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611109

RESUMO

Breast cancer is the most common cancer among women. Metaplastic breast carcinoma (MpBC) is a rare, heterogeneous group of invasive breast carcinomas, which are classified as predominantly triple-negative breast carcinomas (TNBCs; HR-negative/HER2-negative). Histologically, MpBC is classified into six subtypes. Two of these are considered low-grade and the others are high-grade. MpBCs seem to be more aggressive, less responsive to neoadjuvant chemotherapy, and have higher rates of chemoresistance than other TNBCs. MpBCs have a lower survival rate than expected for TNBCs. MpBC treatment represents a challenge, leading to a thorough exploration of the tumor immune microenvironment, which has recently opened the possibility of new therapeutic strategies. The epithelial-mesenchymal transition in MpBC is characterized by the loss of intercellular adhesion, downregulation of epithelial markers, underexpression of genes with biological epithelial functions, upregulation of mesenchymal markers, overexpression of genes with biological mesenchymal functions, acquisition of fibroblast-like (spindle) morphology, cytoskeleton reorganization, increased motility, invasiveness, and metastatic capabilities. This article reviews and summarizes the current knowledge and translational aspects of MpBC.

20.
Brain Sci ; 14(10)2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39452050

RESUMO

BACKGROUND/OBJECTIVES: Cranioplasty (CP) is the main surgical procedure aiming to repair a morphological defect in the skull. It has been shown that early CP is useful for patients with traumatic brain injury (TBI) to achieve functional recovery, whereas few studies have investigated the clinical effects of ultra-late CP on TBI outcomes. METHODS: Here, we describe the clinical course over 2 years of a TBI patient who underwent CP 19 months after fronto-parietal decompressive craniectomy (DC) of a limited size. RESULTS: We found that after ultra-late CP, a meaningful functional recovery (cognitive and motor), with emergence from a minimally conscious state and recovery of functional communication, was revealed. CONCLUSIONS: Our preliminary findings contribute to the actual debate on the timing of CP for this neurosurgical procedure's therapeutic success, as early CP has already been shown.

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