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1.
Proc Natl Acad Sci U S A ; 120(1): e2214418120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36584295

RESUMO

Pheromones play essential roles in reproduction in many species. Prostaglandin F2α (PGF2α) acts as a female reproductive hormone and as a sex pheromone in some species. An olfactory receptor (OR) for PGF2α was recently discovered in zebrafish, but this signaling pathway is evolutionarily labile. To understand the evolution of signals that attract males to fertile females, we used the African cichlid Astatotilapia burtoni and found that adult males strongly prefer fertile female odors. Injection of a prostaglandin synthesis inhibitor abolishes this attractivity of fertile females, indicating these hormones are necessary for pheromonal signaling. Unlike zebrafish, A. burtoni males are insensitive to PGF2α, but they do exhibit strong preference for females injected with PGF2α. This attractiveness is independent of the PGF2α hormonal receptor Ptgfr, indicating that this pheromone signaling derives from PGF2α metabolization into a yet-undiscovered pheromone. We further discovered that fish that are insensitive to PGF2α lack an ortholog for the OR Or114 that zebrafish use to detect PGF2α. These results indicate that PGF2α itself does not directly induce male preference in cichlids. Rather, it plays a vital role that primes females to become attractive via an alternative male OR.


Assuntos
Ciclídeos , Receptores Odorantes , Animais , Feminino , Masculino , Peixe-Zebra , Hormônios , Transdução de Sinais , Feromônios , Prostaglandinas
2.
Front Cell Dev Biol ; 10: 790410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252171

RESUMO

Triple negative breast cancer (TNBC) follows a non-random pattern of metastasis to the bone and brain tissue. Prior work has found that brain-seeking breast tumor cells display altered proteomic profiles, leading to alterations in pathways related to cell signaling, cell cycle, metabolism, and extracellular matrix remodeling. Given the unique microenvironmental characteristics of brain and bone tissue, we hypothesized that brain- or bone-seeking TNBC cells may have altered morphologic or migratory phenotypes from each other, or from the parental TNBC cells, as a function of the biochemical or mechanical microenvironment. In this study, we utilized TNBC cells (MDA-MB-231) that were conditioned to metastasize solely to brain (MDA-BR) or bone (MDA-BO) tissue. We quantified characteristics such as cell morphology, migration, and stiffness in response to cues that partially mimic their final metastatic niche. We have shown that MDA-BO cells have a distinct protrusive morphology not found in MDA-P or MDA-BR. Further, MDA-BO cells migrate over a larger area when on a collagen I (abundant in bone tissue) substrate when compared to fibronectin (abundant in brain tissue). However, migration in highly confined environments was similar across the cell types. Modest differences were found in the stiffness of MDA-BR and MDA-BO cells plated on collagen I vs. fibronectin-coated surfaces. Lastly, MDA-BO cells were found to have larger focal adhesion area and density in comparison with the other two cell types. These results initiate a quantitative profile of mechanobiological phenotypes in TNBC, with future impacts aiming to help predict metastatic propensities to organ-specific sites in a clinical setting.

3.
Int J Surg Pathol ; 29(5): 503-505, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33827319

RESUMO

Pseudo-signet ring parietal cell vacuolation has been described as a mimic of invasive signet ring cell carcinoma. Moreover, signet ring cell carcinoma has been described in a fundic gland polyp. This case demonstrates parietal cell vacuolation in a fundic gland polyp in a patient on a long-term proton pump inhibitor.


Assuntos
Carcinoma de Células em Anel de Sinete/diagnóstico , Fundo Gástrico/patologia , Pólipos/diagnóstico , Neoplasias Gástricas/diagnóstico , Idoso , Biópsia , Diagnóstico Diferencial , Fundo Gástrico/diagnóstico por imagem , Fundo Gástrico/efeitos dos fármacos , Gastrite/tratamento farmacológico , Gastroscopia , Humanos , Masculino , Pólipos/induzido quimicamente , Inibidores da Bomba de Prótons/efeitos adversos , Neoplasias Gástricas/induzido quimicamente
7.
PLoS One ; 12(9): e0184625, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28937983

RESUMO

[18F]-FDOPA is a labeled amino acid (AA) analog used for positron emission tomography (PET) which is gaining increasing interest in the evaluation of brain tumors (BT). The AA-transporter LAT1 has been shown to be involved in [18F]-FDOPA uptake. The aim of this study was to determine whether the [18F]-FDOPA uptake was correlated with level of LAT1 expression in BT. Twenty-eight BT (including 19 gliomas and 9 metastases) were investigated by [18F]-FDOPA-PET prior to surgery and by anti-LAT1 immunohistochemistry on surgical specimens. The quantitative [18F]-FDOPA measured parameters were SUVmax, SUVmean and SUVpeak. LAT1 expression was quantified using a score (0 to 400). A significant [18F]-FDOPA uptake was associated with a LAT1 score ≥ 100 (p = 0.02) but there was no linear correlation between intensity of [18F]-FDOPA uptake and score of LAT1 expression whatever the parameters considered. LAT1 expression alone is not sufficient to explain variation of intensity of [18F]-FDOPA uptake in BT.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Neoplasias Encefálicas/metabolismo , Di-Hidroxifenilalanina/farmacocinética , Radioisótopos de Flúor/farmacocinética , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/cirurgia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Feminino , Glioma/diagnóstico por imagem , Glioma/metabolismo , Glioma/patologia , Glioma/cirurgia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
8.
Virchows Arch ; 470(1): 21-27, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27853865

RESUMO

Gene mutation status assessment of tumors has become standard practice in diagnostic pathology. This is done using samples comprising tumor cells but also non-tumor cells, which may dramatically dilute the proportion of tumor DNA and induce false negative results. Increasing sensitivity of molecular tests presently allows detection of a targeted mutation in a sample with a small percentage of tumor cells, but assessment of tumor cellularity remains essential to adequately interpret the results of molecular tests. Comprehensive tumor cell counting would provide the most reliable approach but is time consuming, and therefore rough global estimations are used, the reliability of which has been questioned in view of their potential clinical impact. The French association for quality assurance in pathology (AFAQAP) conducted two external quality assurance schemes, partly in partnership with the French group of oncology cytogenomics (GFCO). The purpose of the schemes was to (1) evaluate how tumor cellularity is assessed on tissue samples, (2) identify reasons for discrepancies, and (3) provide recommendations for standardization and improvement. Tumor cell percentages in tissue samples of lung and colon cancer were estimated by 40-50 participants, on 10 H&E virtual slides and 20 H&E conventional slides. The average difference between lowest and highest estimated percentage was 66. This was largely due to inadequate definition of cellularity, reflecting confusion between the percentage of tumor cells and the percentage of the area occupied by tumor in the assessed region. The widest range of interobserver variation was observed for samples with dense or scattered lymphocytic infiltrates or with mucinous stroma. Estimations were more accurate in cases with a low percentage of tumor cells. Macrodissection of the most homogeneous area in the tissue reduced inter-laboratory variation. We developed a rating system indicating potential clinical impact of a discrepancy. Fewer discrepancies were clinically relevant since the study was conducted. Although semi-quantitative estimations remain somewhat subjective, their reliability improves when tumor cellularity is adequately defined and heterogeneous tissue samples are macrodissected for molecular analysis.


Assuntos
DNA de Neoplasias/genética , Neoplasias/genética , Neoplasias/patologia , Contagem de Células/métodos , Humanos , Mutação , Neoplasias/diagnóstico , Variações Dependentes do Observador , Reprodutibilidade dos Testes
10.
Int J Surg Pathol ; 24(2): 139-41, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26612847

RESUMO

Breast carcinoma in males is rare although a 4-fold increased incidence is reported in HIV-infected men. Herein we report a case of invasive breast carcinoma in a HIV-positive man on antiretroviral therapy. The carcinoma was associated with features of florid gynecomastia, atypical ductal hyperplasia, ductal carcinoma in situ, and columnar cell change. This combination of morphological changes has not previously been reported in the context of male breast carcinoma and their etiopathological associations are discussed.


Assuntos
Neoplasias da Mama Masculina/patologia , Carcinoma Intraductal não Infiltrante/patologia , Ginecomastia/etiologia , Infecções por HIV , Adulto , Terapia Antirretroviral de Alta Atividade , Neoplasias da Mama Masculina/complicações , Carcinoma Intraductal não Infiltrante/complicações , Humanos , Masculino
12.
Int J Surg Pathol ; 24(4): 353-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26657576

RESUMO

Xanthomas are common in cutaneous sites but may also be seen in unusual locations. In view of the paucity of reported cases, the occurrence of such lesions within the breast stroma would appear to be either unusual, underreported, or ignored. Indeed, most reports of the few breast xanthomas and of the even fewer xanthomatous fibroadenomas reported have appeared in the older literature. Herein, a case of fibroadenoma with multiple foci of xanthoma is reported, the literature is briefly reviewed, and the apparent difference between the previous cases and the current case is highlighted.


Assuntos
Neoplasias da Mama/patologia , Fibroadenoma/patologia , Neoplasias da Mama/diagnóstico , Feminino , Fibroadenoma/diagnóstico , Humanos , Pessoa de Meia-Idade , Xantomatose/patologia
13.
Int J Surg Pathol ; 23(5): 372, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26044823
14.
Int J Surg Pathol ; 22(8): 711, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25161203
15.
Int J Surg Pathol ; 22(6): 528, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25122730
17.
Int J Surg Pathol ; 22(5): 420, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24619015
20.
Int J Surg Pathol ; 22(1): 70, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24345716
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