RESUMO
In Arabidopsis, vacuolar sorting receptor isoform 1 (VSR1) sorts 12S globulins to the protein storage vacuoles during seed development. Vacuolar sorting is mediated by specific protein-protein interactions between VSR1 and the vacuolar sorting determinant located at the C terminus (ctVSD) on the cargo proteins. Here, we determined the crystal structure of the protease-associated domain of VSR1 (VSR1-PA) in complex with the C-terminal pentapeptide (468RVAAA472) of cruciferin 1, an isoform of 12S globulins. The 468RVA470 motif forms a parallel ß-sheet with the switch III residues (127TMD129) of VSR1-PA, and the 471AA472 motif docks to a cradle formed by the cargo-binding loop (95RGDCYF100), making a hydrophobic interaction with Tyr99. The C-terminal carboxyl group of the ctVSD is recognized by forming salt bridges with Arg95. The C-terminal sequences of cruciferin 1 and vicilin-like storage protein 22 were sufficient to redirect the secretory red fluorescent protein (spRFP) to the vacuoles in Arabidopsis protoplasts. Adding a proline residue to the C terminus of the ctVSD and R95M substitution of VSR1 disrupted receptor-cargo interactions in vitro and led to increased secretion of spRFP in Arabidopsis protoplasts. How VSR1-PA recognizes ctVSDs of other storage proteins was modeled. The last three residues of ctVSD prefer hydrophobic residues because they form a hydrophobic cluster with Tyr99 of VSR1-PA. Due to charge-charge interactions, conserved acidic residues, Asp129 and Glu132, around the cargo-binding site should prefer basic residues over acidic ones in the ctVSD. The structural insights gained may be useful in targeting recombinant proteins to the protein storage vacuoles in seeds.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Substituição de Aminoácidos , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cristalografia por Raios X , Mutação de Sentido Incorreto , Conformação Proteica em Folha beta , Domínios Proteicos , Transporte Proteico , Protoplastos/química , Protoplastos/metabolismo , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/metabolismo , Relação Estrutura-Atividade , Vacúolos/química , Vacúolos/genética , Vacúolos/metabolismoRESUMO
Hepatocellular carcinoma (HCC) is the fastest growing cause of cancer death in the United States with the incidence rate more than doubling in 20 years. HCC is unique since a noninvasive diagnosis can be achieved with imaging alone when specific clinical criteria and imaging characteristics are met, obviating the need for tissue sampling. However, HCC is a highly heterogeneous neoplasm. Atypical HCC subtypes vary significantly in their morphology, which can be attributed to specific histologic and molecular features, and can cause deviations from the classic imaging characteristics. The different morphologic subtypes of HCC frequently present a diagnostic challenge for radiologists and pathologists since their imaging and pathologic features can overlap with those of non-HCC malignancies. Identifying an atypical subtype can have important clinical implications. Liver transplant, albeit a scarce and limited resource, is the optimal treatment for conventional HCC, potentially curing both the tumor and the underlying pre-malignant condition. Some HCC subtypes as well as mimickers are associated with unacceptably high recurrence and poor outcome after transplant, and there remains limited data on the role and prognosis of liver transplantation for treatment of rare HCC subtypes. Other subtypes tend to recur later than classic HCC, potentially requiring a different follow-up scheme. This review will discuss the appearance of different HCC subtypes in relation to their histopathologic features. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 3.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Radiologia , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , PrognósticoRESUMO
BACKGROUND: Hepatic artery thrombosis (HAT) is a major complication after liver transplantation that commonly requires re-transplantation. METHODS: We queried the UNOS dataset for all patients transplanted between 1995 and 2015 for HAT. RESULTS: We identified 623 patients who underwent re-transplantation for HAT with a mean age of 51.25 + 10.4 years. The mean BMI was 26.72 kg/m2, and mean MELD score was 19.62 + 9.09. There was a higher proportion of male patients, with higher prevalence of pre-transplant portal vein thrombosis (7.4 vs. 5.4%, p = 0.04), lower incidence of hepatitis C virus infection (29.5 vs. 35.8%, p = 0.002), and shorter waiting time (61 vs. 111 days, p = 0.001) in the HAT group compared to those re-transplanted for other indications. The perioperative 90-day mortality was lower in patients re-transplanted for HAT (16 vs. 20%, p = 0.02). Patients undergoing re-transplantation for HAT had 13% decreased graft survival and 13% increased long-term survival. After case-control matched analysis, graft survival and patient survival were significantly better in the HAT group. Late re-transplantation (>30 days) for HAT was linked to decreased graft and patient survival when compared to those undergoing early re-transplantation (within 30 days). CONCLUSIONS: Improved outcomes were seen in patients undergoing re-transplantation for HAT compared to patients who underwent re-transplantation for other indications. Those re-transplanted late after HAT (>30 days) were associated with worse outcomes when compared to early re-transplantation.
Assuntos
Artéria Hepática/cirurgia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Trombose/cirurgia , Adulto , Fatores Etários , Estudos de Casos e Controles , Feminino , Sobrevivência de Enxerto , Hepatite C/epidemiologia , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Reoperação , Distribuição por SexoRESUMO
INTRODUCTION: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is an established system with reproducible risk of malignancies (ROM) for salivary gland fine needle aspiration (SGFNA). No studies have reviewed the relationship between Milan categories and the resection rate (RR) and time to resection (TTR). METHODS: We searched our database (January 1, 2011 to January 4, 2021) for non-lymphoma SGFNAs and assigned appropriate MSRSGC categories. RR and TTR were calculated and compared for each category. A literature search was performed; RRs and TTRs were compared. RESULTS: Seven hundred and eighty SGFNAs were identified, 333 with follow-up. RR was highest in suspicious for malignancy (SUS, V; 70.6%, n = 12/17), followed by the salivary gland neoplasm of uncertain malignant potential (SUMP, IVb; 69.6%, n = 80/115) and malignant (M, VI; 55.6%, n = 75/135). Among M, primary tumors had a higher RR (65.1%, n = 41/63) than metastases (47.2%, n = 34/72, p = .36). In literature review, SUS had the highest RR (69.3%, n = 233/336) followed by M (61.6%, n = 821/1332) and SUMP (60.2%, n = 632/1050). TTR was shorter in SUS (mean = 32.3 days, median = 25 days). Within the benign neoplasms (BN, IVa), Pleomorphic adenomas (PAs) had a higher RR than Warthin tumors (WTs) (66.3% vs. 37.2%, p < .00001), and a shorter TTR (median = 63 days vs. 90 days). CONCLUSIONS: Tumors classified as SUS had higher RR and at shorter intervals than those classified as SUMP. PAs have higher RRs and more expedient surgery than WTs. Cases classified as M are less likely to undergo follow-up than SUS, perhaps due to a lower RR for metastases.
Assuntos
Adenolinfoma , Adenoma Pleomorfo , Neoplasias das Glândulas Salivares , Humanos , Adenolinfoma/patologia , Adenoma Pleomorfo/patologia , Biópsia por Agulha Fina , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/cirurgia , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares/cirurgia , Glândulas Salivares/patologiaRESUMO
OBJECTIVE: Pt-Mal-LHRH is a newly synthesized chemotherapeutic agent that was designed to selectively target the luteinizing hormone-releasing hormone (LHRH) receptor expressed by triple negative breast cancer (TNBC). The aim of this study was to evaluate the therapeutic dosing, tumor reduction efficacy, and selective distribution of Pt-Mal-LHRH in-vivo. METHODS AND RESULTS: LHRH tissue expression levels in-vivo were investigated using western blotting and LHRH was found to be increased in reproductive tissues (mammary, ovary, uterus). Further, Pt-Mal-LHRH was found to have increased TNBC tumor tissue platinum accumulation compared to carboplatin by inductively coupled plasma mass spectrometry analysis. The platinum family, compound carboplatin, was selected for comparison due to its similar chemical structure and molar equivalent doses were evaluated. Moreover, in-vivo distribution data indicated selective targeting of Pt-Mal-LHRH by enhanced reproductive tissue accumulation compared to carboplatin. Further, TNBC tumor growth was found to be significantly attenuated by Pt-Mal-LHRH compared to carboplatin in both the 4T1 and MDA-MB-231 tumor models. There was a significant reduction in tumor volume in the 4T1 tumor across Pt-Mal-LHRH doses (2.5-20 mg/kg/wk) and in the MDA-MB-231 tumor at the dose of 10 mg/kg/wk in models conducted by an independent contract testing laboratory. CONCLUSION: Our data indicates Pt-Mal-LHRH is a targeting chemotherapeutic agent towards the LHRH receptor and reduces TNBC tumor growth in-vivo. This study supports drug conjugation design models using the LHRH hormone for chemotherapeutic delivery as Pt-Mal-LHRH was found to be a more selective and efficacious than carboplatin. Further examination of Pt-Mal-LHRH is warranted for its clinical use in TNBCs, along with, other reproductive cancers overexpressing the LHRH receptor.
Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Receptores LHRH , Neoplasias de Mama Triplo Negativas/patologia , Carboplatina/uso terapêutico , Platina/uso terapêutico , Hormônio Liberador de Gonadotropina , Linhagem Celular Tumoral , Antineoplásicos/uso terapêuticoRESUMO
BACKGROUND: The World Health Organization (WHO) has recently published a classification for reporting pancreaticobiliary cytopathology with differences compared to the Papanicolaou Society of Cytopathology (PSC) classification. METHODS: Retrospective data were collected from pancreatic endoscopic ultrasound-guided fine-needle aspirations from 2014 to 2017 at a pancreatic cancer center. Absolute risk of malignancy (AROM), relative risk (to benign), performance characteristics, and overall survival were calculated for the entire cohort with comparison of cysts and solid lesions. RESULTS: In total, 2562 cases were included: 16% cyst (n = 411) and 84% solid (n = 2151). The histologic confirmation rate was 43% (n = 1101) and the median follow-up (for benign) was 56 months. For WHO I-VII, overall AROM (%) was 23, 22, 62, 13, 65, 97, and 100; cyst AROM was 7, 0, 19, 13, 38, 78, and 100; and solid AROM was 50, 29, 70, 15, 100, 99, and 100. For PSC I-VI, overall AROM (%) was 23, 29, 64, 0 (IVa), 60 (IVb), 97, and 100; cyst AROM was 7, 0, 19, 0, 21, 78, and 100; and solid AROM was 50, 35, 73, 0, 92, 99, and 100. The difference in relative risk for a cyst (vs. solid) overall was 0.38 for WHO and 0.26 for PSC. WHO and PSC categories showed stratification for the probability of overall survival. CONCLUSIONS: Cystic versus solid lesion type can dramatically affect AROM, particularly for nondiagnostic (I), benign (II), atypical (III), and WHO V categories. WHO IV conveys a similarly low AROM for cystic and solid types. Both classifications stratify the probability of overall survival, including the newly introduced categories WHO IV and WHO V.
Assuntos
Cistos , Neoplasias Pancreáticas , Humanos , Citologia , Estudos Retrospectivos , Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Cistos/patologiaRESUMO
BACKGROUND: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) reports a 25% rate of malignancy (ROM) for the Milan I: Nondiagnostic (ND) category. We clarify the ROM of ND salivary gland fine-needle aspirations (SGFNAs) based on our institutional experience and review of the literature. METHODS: Overall risk of malignancy (OROM) and that for those with surgical/flow cytometric follow-up (FROM) for each category and "all-comers" were calculated for Emory SGFNAs from January 2010 through March 2021. From a literature review of 50 articles using MSRSGC, distribution of diagnoses, rates of follow-up, FROM, and OROM by category were calculated. FROMs and OROMs between ND FNAs and all-comers were compared. Milan I rate was compared with the ratio of Milan I OROM to all-comer OROM. RESULTS: Of 819 SGFNAs at Emory, 12.8% (n = 105/819) were ND. Thirty-two had known follow-up, with 12 (37.5%) being malignant. Nonmucinous cyst contents accounted for 26.7% of ND SGFNAs (n = 28/105); all 7 with surgical follow-up were benign. Of 50 MSRSGC studies, 18.2% (n = 2384/13,129) of SGFNAs were classified as ND, 26.6% (n = 635/2384) with known follow-up. Total FROM and OROM for ND FNAs (15.7% and 4.1%, respectively) were significantly lower than those for all-comers (24.9% and 11.4%, respectively) (p < .001). There was no relationship between rate of ND SGFNA and ND ROM. CONCLUSIONS: The ND category is associated with a lower ROM than that of all-comer SGFNA patients. The "true" ROM for ND SGFNAs is likely best estimated by the 4.1% OROM. SGFNAs showing nonmucinous cyst contents have a particularly low ROM. Rate of ND SGFNAs does not influence ND ROM.
Assuntos
Cistos , Neoplasias das Glândulas Salivares , Biópsia por Agulha Fina , Cistos/patologia , Humanos , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares/patologiaRESUMO
Kaposi sarcoma (KS) can pose diagnostic challenges in biopsy specimens. Multiple histologic variants of cutaneous KS have been described; however, the histomorphologic spectrum of gastrointestinal (GI) KS has not been systematically studied. This large series comprehensively evaluated 46 cases of KS involving the GI tract and identified 7 histomorphologic variants, some that have not been previously described. Five of them are inconspicuous but have unique morphologic patterns, including lymphangioma/lymphangiectatic-like (n=17), mucosal hemorrhage/telangiectatic-like (n=17), mucosal inflammation-like (n=15), granulation tissue-like (n=13), and mucosal prolapse-like (n=4) variants. These variants can be easily misdiagnosed or misinterpreted on routine examination if KS is not considered, and if the immunohistochemical stain for human herpesvirus-8 is not performed. The other 2 morphologic variants present as spindle cell proliferations and are the GI stromal tumor-like (n=8) and inflammatory myofibroblastic tumor-like (n=2). These variants raise a broad differential diagnosis of spindle cell tumors of the GI tract and could pose diagnostic challenges. In summary, GI KS lesions exhibit variable, often unconventional histomorphologic patterns. KS should be included in the differential diagnosis even if features of conventional KS are not seen, particularly in limited biopsies in immunocompromised patients, such as those with human immunodeficiency virus infection. Although the clinical significance of these morphologic variants is yet to be determined, they are nonetheless important from a diagnostic standpoint. Misdiagnosis and delay in appropriate management can be avoided by recognizing the morphologic diversity of GI KS and appropriately utilizing the human herpesvirus-8 immunohistochemical stain.
Assuntos
Tumores do Estroma Gastrointestinal , Herpesvirus Humano 8 , Sarcoma de Kaposi , Neoplasias Cutâneas , Humanos , Sarcoma de Kaposi/diagnóstico , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/patologiaRESUMO
Better prognostication/stratification of pancreatic neuroendocrine tumors (PanNETs) is needed. In this detailed morpheomic study of 163 resected PanNETs, 11 unusual variants, some of which were not previously recognized, and others scarcely documented in the literature, were identified, and their pathologic characteristics were further analyzed. By behavior and clinicopathologic associations, these variants could be grouped into three prognostically different categories. I. More aggressive (20%). Included in this group were the variants that in average showed higher grade and stage and adverse outcome including oncocytic, plasmacytoid, lipid-rich and previously unrecognized hepatoid variants, which often had a more diffuse/broad-band growth pattern, with some also displaying discohesiveness. They were characterized by abundant cytoplasm and often had prominent nucleoli (as seen in metabolically active cells), thus the provisional name "metabolic cell phenotype." Because of their diversion from classical neuroendocrine cytomorphology, these variants created challenges on original diagnostic workup, particularly hepatoid examples, which revealed Arginase 1/Hep Par-1 expression in 50%. II. Less aggressive (10%). These cases either showed signs of maturation, including nested growth, paraganglioid pattern (which was previously unrecognized), and organoid PanNETs such as "ductulo-insular" growth, or showed symplastic/degenerative changes, and despite their paradoxically disconcerting histology, were more benevolent in behavior. III. Undetermined. There were other variants including mammary tubulolobular-like, pseudoglandular, peliotic, and sclerotic PanNETs, which although diagnostically challenging, their biologic significance could not be determined because of rarity or heterogeneous characteristics. Prognostic associations: Features that were significantly different in the more aggressive group than the less aggressive group were median size (5.0 vs 1.6 cm, p < 0.001), percentage of pT3+T4 cases (72% vs 12%, p < 0.001), Ki67 index (5.3% vs 2.3%, p = 0.001), % G2 and G3 cases (77% vs 27%, p < 0.001), and rate of lymph node and distant metastasis (96% vs 27%, p < 0.001). In stepwise logistic regression model using the 3 established prognosticators of T stage, size, and grade along with morphology, only aggressive-morphology (metabolic cell phenotype) was found to be associated with metastatic behavior with an odds ratio of 5.9 with 95% confidence interval (C.I.) 1.688 to 22.945 and p value 0.007. In conclusion, PanNETs display various morphologic patterns that are not only challenging and important diagnostically but appear to have biologic significance. Tumors with more diffuse growth of cells with nucleoli and abundant cytoplasm and/or discohesion (oncocytic, hepatoid, lipid-rich, plasmacytoid PanNETs), provisionally termed "metabolic cell phenotype," show aggressive characteristics and are an independent determinant of adverse outcome and thus may require closer post-surgical follow-up, whereas variants with more degenerative or mature features (ductuloinsular, pleomorphic, paraganglioma-like) appear to be more benevolent despite their more atypical and worrisome morphology.
Assuntos
Tumores Neuroendócrinos/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Idoso , Diferenciação Celular , Proliferação de Células , Estudos de Coortes , Feminino , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Tumores Neuroendócrinos/patologia , Tamanho do Órgão , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Fenótipo , Prognóstico , Medição de RiscoRESUMO
Sickle cell disease has a wide range of hepatic manifestations, with acute intrahepatic cholestasis being one of the rarest and most fatal, often resulting in acute fulminant hepatic failure. Liver transplantation is an emerging but rarely utilized treatment for hepatic failure in the setting of sickle cell disease. Few such cases have been reported in the literature, with little emphasis on histopathologic correlation. We report a case of acute intrahepatic cholestasis in a patient with sickle cell disease who underwent orthotropic liver transplantation and describe novel correlating histopathologic features. The patient is a 29-year-old man who presented with hyperbilirubinemia, acute kidney injury, and coagulopathy. He was diagnosed clinically with acute intrahepatic cholestasis and received an orthotropic liver transplant. The explanted liver demonstrated marked sinusoidal expansion by sickled erythrocytes, hyperplastic Kupffer cells, and extramedullary hematopoiesis. There was extensive sinusoidal and centrizonal fibrosis with occlusion of central veins reminiscent of chronic sinusoidal obstructive syndrome, a previously undescribed pattern of injury. This case represents one of the few reported cases of sickle cell intrahepatic cholestasis treated by transplantation and demonstrates the rarely reported histopathologic features and gives insight to a potentially new mechanism of injury in these patients. Familiarity with the morphologic features of sickle cell hepatopathy and its clinical manifestations is important as transplantation in sickle cell-related liver injury increases in frequency.
Assuntos
Anemia Falciforme/complicações , Colestase Intra-Hepática/terapia , Oxigenação por Membrana Extracorpórea/métodos , Transplante de Fígado/métodos , Fígado/patologia , Doença Aguda/terapia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Adulto , Biópsia , Colestase Intra-Hepática/etiologia , Colestase Intra-Hepática/patologia , Humanos , Hiperbilirrubinemia/etiologia , Hiperbilirrubinemia/terapia , Fígado/cirurgia , MasculinoRESUMO
Two nuclear plant disasters occurring within a span of 25 years threaten health and genome integrity both in Fukushima and Chernobyl. Search for remedies capable of enhancing DNA repair efficiency and radiation resistance in humans appears to be a urgent problem for now. XRCC4 is an important enhancer in promoting repair pathway triggered by DNA double-strand break (DSB). In the context of radiation therapy, active XRCC4 could reduce DSB-mediated apoptotic effect on cancer cells. Hence, developing XRCC4 inhibitors could possibly enhance radiotherapy outcomes. In this study, we screened traditional Chinese medicine (TCM) database, TCM Database@Taiwan, and have identified three potent inhibitor agents against XRCC4. Through molecular dynamics simulation, we have determined that the protein-ligand interactions were focused at Lys188 on chain A and Lys187 on chain B. Intriguingly, the hydrogen bonds for all three ligands fluctuated frequently but were held at close approximation. The pi-cation interactions and ionic interactions mediated by o-hydroxyphenyl and carboxyl functional groups respectively have been demonstrated to play critical roles in stabilizing binding conformations. Based on these results, we reported the identification of potential radiotherapy enhancers from TCM. We further characterized the key binding elements for inhibiting the XRCC4 activities.