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1.
PeerJ ; 10: e12715, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35036096

RESUMO

BACKGROUND: Improved detection of hepatocellular carcinoma (HCC) is needed, as current detection methods, such as alpha fetoprotein (AFP) and ultrasound, suffer from poor sensitivity. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate many cellular functions and impact cancer development and progression. Notably, miRNAs are detectable in saliva and have shown potential as non-invasive biomarkers for a number of cancers including breast, oral, and lung cancers. Here, we present, to our knowledge, the first report of salivary miRNAs in HCC and compare these findings to patients with cirrhosis, a high-risk cohort for HCC. METHODS: We performed small RNA sequencing in 20 patients with HCC and 19 with cirrhosis. Eleven patients with HCC had chronic liver disease, and analyses were performed with these samples combined and stratified by the presence of chronic liver disease. P values were adjusted for multiple comparisons using a false discovery rate (FDR) approach and miRNA with FDR P < 0.05 were considered statistically significant. Differential expression of salivary miRNAs was compared to a previously published report of miRNAs in liver tissue of patients with HCC vs cirrhosis. Support vector machines and leave-one-out cross-validation were performed to determine if salivary miRNAs have predictive potential for detecting HCC. RESULTS: A total of 4,565 precursor and mature miRNAs were detected in saliva and 365 were significantly different between those with HCC compared to cirrhosis (FDR P < 0.05). Interestingly, 283 of these miRNAs were significantly downregulated in patients with HCC. Machine-learning identified a combination of 10 miRNAs and covariates that accurately classified patients with HCC (AUC = 0.87). In addition, we identified three miRNAs that were differentially expressed in HCC saliva samples and in a previously published study of miRNAs in HCC tissue compared to cirrhotic liver tissue. CONCLUSIONS: This study demonstrates, for the first time, that miRNAs relevant to HCC are detectable in saliva, that salivary miRNA signatures show potential to be highly sensitive and specific non-invasive biomarkers of HCC, and that additional studies utilizing larger cohorts are needed.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/diagnóstico , MicroRNAs/genética , Projetos Piloto , Neoplasias Hepáticas/diagnóstico , Biomarcadores Tumorais/genética , Cirrose Hepática/diagnóstico
2.
Liver Cancer Int ; 2(2): 33-44, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34541549

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a leading causes of cancer mortality worldwide. Improved tools are needed for detecting HCC so that treatment can begin as early as possible. Current diagnostic approaches and existing biomarkers, such as alpha-fetoprotein (AFP) lack sensitivity, resulting in too many false negative diagnoses. Machine-learning may be able to identify combinations of biomarkers that provide more robust predictions and improve sensitivity for detecting HCC. We sought to evaluate whether metabolites in patient saliva could distinguish those with HCC, cirrhosis, and those with no documented liver disease. METHODS AND RESULTS: We tested 125 salivary metabolites from 110 individuals (43 healthy, 37 HCC, 30 cirrhosis) and identified 4 metabolites that displayed significantly different abundance between groups (FDR P <.2). We also developed four tree-based, machine-learning models, optimized to include different numbers of metabolites, that were trained using cross-validation on 99 patients and validated on a withheld test set of 11 patients. A model using 12 metabolites -octadecanol, acetophenone, lauric acid, 1-monopalmitin, dodecanol, salicylaldehyde, glycyl-proline, 1-monostearin, creatinine, glutamine, serine and 4-hydroxybutyric acid- had a cross-validated sensitivity of 84.8%, specificity of 92.4% and correctly classified 90% of the HCC patients in the test cohort. This model outperformed previously reported sensitivities and specificities for AFP (20-100ng/ml) (61%, 86%) and AFP plus ultrasound (62%, 88%). CONCLUSIONS AND IMPACT: Metabolites detectable in saliva may represent products of disease pathology or a breakdown in liver function. Notably, combinations of salivary metabolites derived from machine-learning may serve as promising non-invasive biomarkers for the detection of HCC.

3.
J Biol Chem ; 296: 100268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33837726

RESUMO

Degranulation, a fundamental effector response from mast cells (MCs) and platelets, is an example of regulated exocytosis. This process is mediated by SNARE proteins and their regulators. We have previously shown that several of these proteins are essential for exocytosis in MCs and platelets. Here, we assessed the role of the SNARE protein SNAP23 using conditional knockout mice, in which SNAP23 was selectively deleted from either the megakaryocyte/platelet or connective tissue MC lineages. We found that removal of SNAP23 in platelets results in severe defects in degranulation of all three platelet secretory granule types, i.e., alpha, dense, and lysosomal granules. The mutation also induces thrombocytopenia, abnormal platelet morphology and activation, and reduction in the number of alpha granules. Therefore, the degranulation defect might not be secondary to an intrinsic failure of the machinery mediating regulated exocytosis in platelets. When we removed SNAP23 expression in MCs, there was a complete developmental failure in vitro and in vivo. The developmental defects in platelets and MCs and the abnormal translocation of membrane proteins to the surface of platelets indicate that SNAP23 is also involved in constitutive exocytosis in these cells. The MC conditional deletant animals lacked connective tissue MCs, but their mucosal MCs were normal and expanded in response to an antigenic stimulus. We used this mouse to show that connective tissue MCs are required and mucosal MCs are not sufficient for an anaphylactic response.


Assuntos
Anafilaxia/imunologia , Plaquetas/imunologia , Tecido Conjuntivo/imunologia , Mastócitos/imunologia , Proteínas Qb-SNARE/imunologia , Proteínas Qc-SNARE/imunologia , Anafilaxia/genética , Anafilaxia/patologia , Animais , Plaquetas/patologia , Tecido Conjuntivo/patologia , Exocitose/genética , Exocitose/imunologia , Mastócitos/patologia , Camundongos , Camundongos Knockout , Proteínas Qb-SNARE/genética , Proteínas Qc-SNARE/genética , Vesículas Secretórias/genética , Vesículas Secretórias/imunologia
4.
J Neurol Surg B Skull Base ; 81(5): 505-510, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33134017

RESUMO

Objectives The main purpose of this article is to examine a single-center cohort of patients with nasopharyngeal adenoid cystic carcinoma (ACC) for pathologic features, skull base invasion, overall survival, and disease-free survival, with a focus on response to proton beam radiation therapy. Design, Setting, and Participants Single-center institutional cancer registry was used to retrospectively identify and analyze outcomes for 12 patients treated for ACC of the nasopharynx from 2000 to 2016. Main Outcomes and Measures Primary outcomes included 5-year overall survival and locoregional control. Statistical analysis was performed using STATA 12.0 (STATACorp, College Station, Texas, United States). Spearman's rank order correlation was used for ordinal, monotonic variables with p -values <0.05 considered statistically significant. Survival analysis was performed by Kaplan-Meier method; comparison between groups was performed using log-rank test. Results Twelve patients with ACC of the nasopharynx were included. All patients presented with advanced disease and were treated with primary radiation therapy, typically proton beam therapy. Only two underwent a surgical attempt at resection. A majority of cases had a cribriform growth pattern. The 5-year survival was 75% and rate of locoregional control rate at 5 years was 50%, comparable to other ACC cohort studies that included earlier stage tumors in various subsites that were surgically resected. Conclusions Although ACC is traditionally noted to be radioresistant, ACC of the nasopharynx was responsive to radiotherapy in our cohort, despite advanced stage and skull base invasion. Reasons for this improved survival are unclear and suggest the need for further pathologic and genetic characterization of nasopharyngeal ACC.

5.
J Neurol Surg Rep ; 80(4): e41-e43, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31737465

RESUMO

Introduction Human papillomavirus (HPV) related multiphenotypic sinonasal carcinoma (HMSC) is a newly described entity. The prognosis of this neoplasm is not well understood, but cases often demonstrate high-grade features and paradoxically indolent behavior. Case Report We present the case of a 65-year-old man referred with unilateral nasal congestion and epistaxis. Nasal endoscopy and imaging revealed an expansile mass filling the left nasal cavity. The patient underwent endoscopic-assisted medial maxillectomy, with complete resection and negative margins. Pathology revealed a basaloid tumor consisting of solid nests with multiple foci of cribriform architecture, with positivity for high-risk HPV, thus supporting the diagnosis of HMSC. Postoperatively, the patient received 66.6-Gy adjuvant three-dimensional proton therapy. Twenty-three months after surgical resection, he developed enlarging pulmonary nodules with biopsy features consistent with the primary sinonasal tumor. He was treated with three cycles of chemotherapy and eight cycles of immunotherapy, progressing on both therapies. He remains on palliative chemotherapy. Conclusion Here, we present a case of HMSC with early and progressive distant metastasis. We aim to add to an understanding of the behavior of this entity. Although this neoplasm may typically be indolent, further classification of high-risk features is necessary to identify rare aggressive cases.

6.
J Biol Chem ; 294(9): 3012-3023, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30563839

RESUMO

Mast cells (MCs) participate in allergy, inflammation, and defense against pathogens. They release multiple immune mediators via exocytosis, a process that requires SNARE proteins, including syntaxins (Stxs). The identity of the Stxs involved in MC exocytosis remains controversial. Here, we studied the roles of Stx3 and -4 in fully developed MCs from conditional knockout mice by electrophysiology and EM, and found that Stx3, and not Stx4, is crucial for MC exocytosis. The main defect seen in Stx3-deficient MCs was their inability to engage multigranular compound exocytosis, while leaving most single-vesicle fusion events intact. We used this defect to show that this form of exocytosis is not only required to accelerate MC degranulation but also essential to achieve full degranulation. The exocytic defect was severe but not absolute, indicating that an Stx other than Stx3 and -4 is also required for exocytosis in MCs. The removal of Stx3 affected only regulated exocytosis, leaving other MC effector responses intact, including the secretion of cytokines via constitutive exocytosis. Our in vivo model of passive systemic anaphylaxis showed that the residual exocytic function of Stx3-deficient MCs was sufficient to drive a full anaphylactic response in mice.


Assuntos
Exocitose , Mastócitos/citologia , Proteínas Qa-SNARE/metabolismo , Animais , Contagem de Células , Degranulação Celular , Diferenciação Celular , Técnicas de Inativação de Genes , Cinética , Camundongos , Proteínas Qa-SNARE/deficiência , Proteínas Qa-SNARE/genética
7.
J Biol Chem ; 293(19): 7148-7159, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29599294

RESUMO

Mast cells (MCs) play pivotal roles in many inflammatory conditions including infections, anaphylaxis, and asthma. MCs store immunoregulatory compounds in their large cytoplasmic granules and, upon stimulation, secrete them via regulated exocytosis. Exocytosis in many cells requires the participation of Munc18 proteins (also known as syntaxin-binding proteins), and we found that mature MCs express all three mammalian isoforms: Munc18-1, -2, and -3. To study their functions in MC effector responses and test the role of MC degranulation in anaphylaxis, we used conditional knockout (cKO) mice in which each Munc18 protein was deleted exclusively in MCs. Using recordings of plasma membrane capacitance for high-resolution analysis of exocytosis in individual MCs, we observed an almost complete absence of exocytosis in Munc18-2-deficient MCs but intact exocytosis in MCs lacking Munc18-1 or Munc18-3. Stereological analysis of EM images of stimulated MCs revealed that the deletion of Munc18-2 also abolishes the homotypic membrane fusion required for compound exocytosis. We confirmed the severe defect in regulated exocytosis in the absence of Munc18-2 by measuring the secretion of mediators stored in MC granules. Munc18-2 cKO mice had normal morphology, development, and distribution of their MCs, indicating that Munc18-2 is not essential for the migration, retention, and maturation of MC-committed progenitors. Despite that, we found that Munc18-2 cKO mice were significantly protected from anaphylaxis. In conclusion, MC-regulated exocytosis is required for the anaphylactic response, and Munc18-2 is the sole Munc18 isoform that mediates membrane fusion during MC degranulation.


Assuntos
Exocitose/fisiologia , Mastócitos/metabolismo , Proteínas Munc18/fisiologia , Anafilaxia/fisiopatologia , Animais , Degranulação Celular , Deleção de Genes , Mastócitos/ultraestrutura , Fusão de Membrana/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica , Proteínas Munc18/genética , Técnicas de Patch-Clamp
8.
J Biol Chem ; 293(1): 345-358, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29141910

RESUMO

Mast cells (MCs) are involved in host defenses against pathogens and inflammation. Stimulated MCs release substances stored in their granules via regulated exocytosis. In other cell types, Munc13 (mammalian homolog of Caenorhabditis elegans uncoordinated gene 13) proteins play essential roles in regulated exocytosis. Here, we found that MCs express Munc13-2 and -4, and we studied their roles using global and conditional knock-out (KO) mice. In a model of systemic anaphylaxis, we found no difference between WT and Munc13-2 KO mice, but global and MC-specific Munc13-4 KO mice developed less hypothermia. This protection correlated with lower plasma histamine levels and with histological evidence of defective MC degranulation but not with changes in MC development, distribution, numbers, or morphology. In vitro assays revealed that the defective response in Munc13-4-deficient MCs was limited to regulated exocytosis, leaving other MC secretory effector responses intact. Single cell capacitance measurements in MCs from mouse mutants differing in Munc13-4 expression levels in their MCs revealed that as levels of Munc13-4 decrease, the rate of exocytosis declines first, and then the total amount of exocytosis decreases. A requirement for Munc13-2 in MC exocytosis was revealed only in the absence of Munc13-4. Electrophysiology and EM studies uncovered that the number of multigranular compound events (i.e. granule-to-granule homotypic fusion) was severely reduced in the absence of Munc13-4. We conclude that although Munc13-2 plays a minor role, Munc13-4 is essential for regulated exocytosis in MCs, and that this MC effector response is required for a full anaphylactic response.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Anafilaxia , Animais , Modelos Animais de Doenças , Exocitose/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Mastócitos/metabolismo , Mastócitos/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Isoformas de Proteínas , Transporte Proteico
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