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1.
J Clin Oncol ; 41(30): 4714-4720, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37847995

RESUMO

PURPOSE: Patients with advanced pancreatic cancer have a poor prognosis and there have been no improvements in survival since the introduction of gemcitabine in 1996. Pancreatic tumors often overexpress human epidermal growth factor receptor type 1 (HER1/EGFR) and this is associated with a worse prognosis. We studied the effects of adding the HER1/EGFR-targeted agent erlotinib to gemcitabine in patients with unresectable, locally advanced, or metastatic pancreatic cancer. PATIENTS AND METHODS: Patients were randomly assigned 1:1 to receive standard gemcitabine plus erlotinib (100 or 150 mg/d orally) or gemcitabine plus placebo in a double-blind, international phase III trial. The primary end point was overall survival. RESULTS: A total of 569 patients were randomly assigned. Overall survival based on an intent-to-treat analysis was significantly prolonged on the erlotinib/gemcitabine arm with a hazard ratio (HR) of 0.82 (95% CI, 0.69 to 0.99; P = .038, adjusted for stratification factors; median 6.24 months v 5.91 months). One-year survival was also greater with erlotinib plus gemcitabine (23% v 17%; P = .023). Progression-free survival was significantly longer with erlotinib plus gemcitabine with an estimated HR of 0.77 (95% CI, 0.64 to 0.92; P = .004). Objective response rates were not significantly different between the arms, although more patients on erlotinib had disease stabilization. There was a higher incidence of some adverse events with erlotinib plus gemcitabine, but most were grade 1 or 2. CONCLUSION: To our knowledge, this randomized phase III trial is the first to demonstrate statistically significantly improved survival in advanced pancreatic cancer by adding any agent to gemcitabine. The recommended dose of erlotinib with gemcitabine for this indication is 100 mg/d.

2.
J Clin Oncol ; 41(7): 1331-1338, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36827742

RESUMO

PURPOSE: Immunohistochemistry (IHC) is a newer technique for assessing the estrogen receptor (ER) status of breast cancers, with the potential to overcome many of the shortcomings associated with the traditional ligand-binding assay (LBA). The purpose of this study was to evaluate the ability of ER status determination by IHC, compared with LBA, to predict clinical outcome-especially response to adjuvant endocrine therapy-in a large number of patients with long-term clinical follow-up. PATIENTS AND METHODS: ER status was evaluated in 1,982 primary breast cancers by IHC on formalin-fixed paraffin-embedded tissue sections, using antibody 6F11 and standard methodology. Slides were scored on a scale representing the estimated proportion and intensity of positive-staining tumor cells (range, 0 to 8). Results were compared with ER values obtained by the LBA in the same tumors and to clinical outcome. RESULTS: An IHC score of greater than 2 (corresponding to as few as 1% to 10% weakly positive cells) was used to define ER positivity on the basis of a univariate cut-point analysis of all possible scores and disease-free survival (DFS) in patients receiving any adjuvant endocrine therapy. Using this definition, 71% of all tumors were determined to be ER-positive by IHC, and the level of agreement with the LBA was 86%. In multivariate analyses of patients receiving adjuvant endocrine therapy alone, ER status determined by IHC was better than that determined by the LBA at predicting improved DFS (hazard ratios/P = 0.474/.0008 and 0.707/.3214, respectively) and equivalent at predicting overall survival (0.379/.0001 and 0.381/.0003, respectively). CONCLUSION: IHC is superior to the LBA for assessing ER status in primary breast cancer because it is easier, safer, and less expensive, and has an equivalent or better ability to predict response to adjuvant endocrine therapy.

3.
Am J Med Genet A ; 191(3): 776-785, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36537114

RESUMO

WWOX biallelic loss-of-function pathogenic single nucleotide variants (SNVs) and copy number variants (CNVs) including exonic deletions and duplications cause WWOX-related epileptic encephalopathy (WOREE) syndrome. This disorder is characterized by refractory epilepsy, axial hypotonia, peripheral hypertonia, progressive microcephaly, and premature death. Here we report five patients with WWOX biallelic predicted null variants identified by exome sequencing (ES), genome sequencing (GS), and/or chromosomal microarray analysis (CMA). SNVs and intragenic deletions of one or more exons were commonly reported in WOREE syndrome patients which made the genetic diagnosis challenging and required a combination of different diagnostic technologies. These patients presented with severe, developmental and epileptic encephalopathy (DEE), and other cardinal features consistent with WOREE syndrome. This report expands the clinical phenotype associated with this condition, including failure to thrive in most patients and epilepsy that responded to a ketogenic diet in three patients. Dysmorphic features and abnormal prenatal findings were not commonly observed. Additionally, recurrent pancreatitis and sensorineural hearing loss each were observed in single patients. In summary, these phenotypic features broaden the clinical spectrum of WOREE syndrome.


Assuntos
Encefalopatias , Epilepsia Generalizada , Epilepsia , Síndromes Epilépticas , Feminino , Gravidez , Humanos , Epilepsia/diagnóstico , Epilepsia/genética , Síndromes Epilépticas/genética , Encefalopatias/genética , Epilepsia Generalizada/genética , Éxons , Oxidorredutase com Domínios WW/genética , Proteínas Supressoras de Tumor/genética
4.
J Neurosurg Pediatr ; : 1-7, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35901680

RESUMO

OBJECTIVE: In utero repair of fetal posterior cephaloceles (meningocele and encephalocele) is being performed based on the premise that fetal surgery prevents progressive herniation of neural tissue and brain damage during pregnancy. However, the extent to which progressive herniation occurs during pregnancy, specifically from prenatal diagnosis to after delivery, is not well known. The objective of this study was to describe the natural history of patients with fetal cephaloceles focusing on the incidence of progressive herniation. METHODS: The authors conducted a retrospective cohort study of all patients referred to their center for posterior fetal cephalocele between 2006 and 2021. All patients underwent prenatal and postnatal MRI. Progressive herniation (primary outcome) was defined as an increase in the absolute volume of neural tissue within the cephalocele of > 5% or new herniation of a critical structure into the cephalocele. Total brain and cephalocele volumes were calculated to determine herniation progression from prenatal to postnatal MRI. Information on the presence of hydrocephalus, epilepsy, and developmental delay (secondary outcomes) was collected at 1 year of age. RESULTS: Twenty patients met all study criteria. Ten patients (50%; 95% CI 0.27-0.73) demonstrated progressive herniation from prenatal to postnatal MRI. Three patients with progressive herniation were diagnosed with a meningocele prenatally and had an encephalocele postnatally. Two patients without progression had meningocele identified prenatally that regressed and became atretic by birth. Both prenatal hindbrain herniation (p = 0.03) and prenatal microcephaly (p = 0.05) were predictive of progressive herniation. The rates of hydrocephalus (44%), epilepsy (44%), and developmental delay (63%) were not associated with the occurrence of progressive herniation in this study. CONCLUSIONS: In this study, progressive herniation was not a rare event (50%). Fetal hindbrain herniation and fetal microcephaly were associated with the occurrence of progressive herniation. These results support further investigations into why progressive herniation occurs in utero and if progressive cerebral herniation in utero plays a significant role in determining clinical outcome.

5.
J Clin Oncol ; 40(18): 2004-2012, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35108031

RESUMO

PURPOSE: To determine whether prophylactic use of compression sleeves prevents arm swelling in women who had undergone axillary lymph node dissection for breast cancer surgery. METHODS: Women (n = 307) were randomly assigned to either a compression or control group. In addition to usual postoperative care, the compression group received two compression sleeves to wear postoperatively until 3 months after completing adjuvant treatments. Arm swelling was determined using bioimpedance spectroscopy (BIS) thresholds and relative arm volume increase (RAVI). Incidence and time free from arm swelling were compared using Kaplan-Meier analyses. Hazard ratios (HRs) were estimated from Cox regression models for BIS and RAVI thresholds independently. In addition, time to documentation of the first minimally important difference (MID) in four scales of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and the breast cancer-specific (BR23) questionnaire was analyzed. RESULTS: The HR for developing arm swelling in the compression group relative to the control group was 0.61 (95% CI, 0.43 to 0.85; P = .004) on the basis of BIS and 0.56 (95% CI, 0.33 to 0.96; P = .034) on the basis of RAVI. The estimated cumulative incidence of arm swelling at 1 year was lower in the compression group than the control group on the basis of BIS (42% v 52%) and RAVI (14% v 25%). HRs for time from baseline to the first change of the minimally important difference were not statistically significant for any of the four scales of EORTC QLQ-30 and BR23 questionnaires. CONCLUSION: Prophylactic use of compression sleeves compared with the control group reduced and delayed the occurrence of arm swelling in women at high risk for lymphedema in the first year after surgery for breast cancer.


Assuntos
Linfedema Relacionado a Câncer de Mama , Neoplasias da Mama , Linfedema , Braço/patologia , Linfedema Relacionado a Câncer de Mama/epidemiologia , Linfedema Relacionado a Câncer de Mama/etiologia , Linfedema Relacionado a Câncer de Mama/prevenção & controle , Neoplasias da Mama/tratamento farmacológico , Edema , Feminino , Humanos , Incidência , Excisão de Linfonodo/efeitos adversos , Linfedema/epidemiologia , Linfedema/etiologia , Linfedema/prevenção & controle , Qualidade de Vida
6.
Clin Cancer Res ; 27(20): 5472-5481, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34312215

RESUMO

To address the need for clinical investigators in oncology, American Association for Cancer Research (AACR) and American Society for Clinical Oncology (ASCO) established the Methods in Clinical Cancer Research Workshop (MCCRW). The workshop's objectives were to: (i) provide training in the methods, design, and conduct of clinical trials; (ii) ensure that clinical trials met federal and international ethical guidelines; (iii) evaluate the effectiveness of the workshop; and (iv) create networking opportunities for young investigators with mentoring senior faculty. Educational methods included: (i) didactic lectures, (ii) Small Group Discussion Sessions, (iii) Protocol Development Groups, and (iv) one-on-one mentoring. Learning focused on the development of an Institutional Review Board (IRB)-ready protocol, which was submitted on the last day of the workshop. Evaluation methods included: (i) pre- and postworkshop tests, (ii) students' workshop evaluations, (iii) faculty's ratings of protocol development, (iv) students' productivity in clinical research after the workshop, and (v) an independent assessment of the workshop. From 1996 to 2014, 1,932 students from diverse backgrounds attended the workshop. There was a significant improvement in the students' level of knowledge from the pre- to the postworkshop exams (P < 0.001). Across the classes, student evaluations were very favorable. At the end of the workshop, faculty rated 92% to 100% of the students' protocols as ready for IRB submission. Intermediate and long-term follow-ups indicated that more than 92% of students were actively involved in patient-related research, and 66% had implemented five or more protocols. This NCI-sponsored MCCRW has had a major impact on the training of clinicians in their ability to design and implement clinical trials in cancer research.


Assuntos
Pesquisa Biomédica/economia , Pesquisa Biomédica/educação , Organização do Financiamento , Oncologia , Neoplasias , Pesquisadores/economia , Pesquisadores/educação , Sociedades Médicas , Pesquisa Biomédica/métodos , Humanos , Estados Unidos
7.
J Pediatr Hematol Oncol ; 43(2): e195-e197, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31764519

RESUMO

Neurocutaneous melanocytosis (NCM) is a disorder characterized by multiple or large congenital nevi and excessive proliferation of melanocytes in the leptomeninges and brain parenchyma. The majority of NCM is a result of somatic mosaicism due to a single postzygotic mutation in codon 61 of NRAS. Patients with NCM are at high risk of developing leptomeningeal melanoma. The prognosis for leptomeningeal melanoma is poor with no known effective treatment options. We describe the clinical features, treatment, and outcome of 4 children with NCM and leptomeningeal melanoma and discuss the latest molecular findings and treatment options for this rare condition.


Assuntos
GTP Fosfo-Hidrolases/genética , Melanoma/patologia , Melanose/complicações , Proteínas de Membrana/genética , Neoplasias Meníngeas/patologia , Síndromes Neurocutâneas/complicações , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Melanoma/tratamento farmacológico , Melanoma/etiologia , Melanose/genética , Melanose/patologia , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/etiologia , Mutação , Síndromes Neurocutâneas/genética , Síndromes Neurocutâneas/patologia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
8.
PLoS One ; 15(2): e0228507, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32045434

RESUMO

Human chorionic gonadotropin (hCG) is a glycoprotein hormone that is essential for the maintenance of pregnancy. Glycosylation of hCG is known to be essential for its biological activity. "Hyperglycosylated" variants secreted during early pregnancy have been proposed to be involved in initial implantation of the embryo and as a potential diagnostic marker for gestational diseases. However, what constitutes "hyperglycosylation" is not yet fully understood. In this study, we perform comparative N-glycomic analysis of hCG expressed in the same individuals during early and late pregnancy to help provide new insights into hCG function, reveal new targets for diagnostics and clarify the identity of hyperglycosylated hCG. hCG was isolated in urine collected from women at 7 weeks and 20 weeks' gestation. hCG was also isolated in urine from women diagnosed with gestational trophoblastic disease (GTD). We used glycomics methodologies including matrix assisted laser desorption/ionisation-time of flight (MALDI-TOF) mass spectrometry (MS) and MS/MS methods to characterise the N-glycans associated with hCG purified from the individual samples. The structures identified on the early pregnancy (EP-hCG) and late pregnancy (LP-hCG) samples corresponded to mono-, bi-, tri-, and tetra-antennary N-glycans. A novel finding was the presence of substantial amounts of bisected type N-glycans in pregnancy hCG samples, which were present at much lower levels in GTD samples. A second novel observation was the presence of abundant LewisX antigens on the bisected N-glycans. GTD-hCG had fewer glycoforms which constituted a subset of those found in normal pregnancy. When compared to EP-hCG, GTD-hCG samples had decreased signals for tri- and tetra-antennary N-glycans. In terms of terminal epitopes, GTD-hCG had increased signals for sialylated structures, while LewisX antigens were of very minor abundance. hCG carries the same N-glycans throughout pregnancy but in different proportions. The N-glycan repertoire is more diverse than previously reported. Bisected and LewisX structures are potential targets for diagnostics. hCG isolated from pregnancy urine inhibits NK cell cytotoxicity in vitro at nanomolar levels and bisected type glycans have previously been implicated in the suppression of NK cell cytotoxicity, suggesting that hCG-related bisected type N-glycans may directly suppress NK cell cytotoxicity.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Polissacarídeos/metabolismo , Processamento de Proteína Pós-Traducional , Sequência de Carboidratos , Gonadotropina Coriônica Humana Subunidade beta/sangue , Gonadotropina Coriônica Humana Subunidade beta/urina , Feminino , Idade Gestacional , Doença Trofoblástica Gestacional/sangue , Doença Trofoblástica Gestacional/metabolismo , Doença Trofoblástica Gestacional/urina , Glicômica/métodos , Glicosilação , Humanos , Gravidez , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem
9.
Eur Arch Otorhinolaryngol ; 277(4): 1155-1165, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31897720

RESUMO

PURPOSE: Adequacy of surgical margins impacts outcomes in oral cancer. We sought to determine whether close and positive margins have different outcomes in patients with oral cancer. METHODS: Retrospective data from 612 patients with oral carcinoma were analyzed for the effect of margin status on locoregional recurrence-free survival (LRFS), disease-free survival (DFS) and overall survival (OS). RESULTS: A total of 90 cases (14.7%) had close margins and 26 patients (4.2%) had positive margins. Recurrences were documented in 173 patients (28%), of which 137 (22% of the study sample) were locoregional, and 164 patients (27%) had died. Among patients with close or positive margins, a cutoff of 1 mm optimally separated LRFS (adjusted p = 0.0190) and OS curves (adjusted p = 0.0168) whereas a cutoff of 2 mm was sufficient to significantly separate DFS curves (adjusted p = 0.0281). CONCLUSIONS: Patients with oral carcinoma with positive margins (< 1 mm) had poorer outcomes compared to those with close margins (1-5 mm) in terms of LRFS, DFS and OS. There is a suggestion that a cutoff of < 2 mm might provide slightly more separation for DFS.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/cirurgia , Humanos , Margens de Excisão , Neoplasias Bucais/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
11.
Springerplus ; 5: 14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26759753

RESUMO

PURPOSE: Women with breast cancer are at increased risk of second malignancy (SM). However, the impact of race and the hormone receptor (HR) status of the primary breast tumor on risk of SM are not known. The purpose of this study is to analyze the incidence of SM in women with a history of breast cancer according to race and HR status. METHODS: In the surveillance, epidemiology, and end results database, multiple primary standardized incidence ratio sessions were used to compare the incidence of SM in women with a history breast cancer to the cancer incidence in the general population. Analyses of SM by age, race, and hormone-receptor status were performed using the absolute excess risk (AER) and observed/expected (O/E) ratio. RESULTS: Younger black women (under the age of 50) were at greater risk of SM with an AER = 76.03 (O/E = 2.3, 95 % CI = 12.19-2.4) compared to younger white women who had an AER = 38.59 (O/E = 1.55, 95 % CI = 1.53-1.58). Older black women (50 years and older) had at an increased risk of SM with an AER = 42.26 (O/E = 1.3, 95 % CI = 1.26-1.34) compared to older white women who had an AER = 11.56 (O/E = 1.07, 95 % CI = 1.06-1.08). Second breast malignancy is the predominant SM in both black and white women. Women with hormone-receptor (HR)-negative breast cancer had higher risk of SMs with an AER = 43.53 (O/E = 1.41, 95 % CI = 1.38- 0.145-3.31) compared to women with HR-positive disease with an AER = 21.43 (O/E = 1.17, 95 % CI = 1.16-0.1.18). In HR-negative women, younger black women had an AER = 96.46 (O/E = 2.99, 95 % CI = 2.70-3.31), younger white women had an AER = 66 (O/E = 2.25, 95 % CI = 2.13-2.36), older black women had an AER = 58.58 (O/E = 1.45, 95 % CI = 1.34-1.57), and older white women had an AER = 20.88 (O/E = 1.14, 95 % CI = 1.11-1.18). CONCLUSIONS: Black breast cancer survivors and women with HR-negative breast cancer are at increased risk of SM, which deserves further evaluation to understand the biological and clinical basis for this increased risk.

12.
Environ Sci Pollut Res Int ; 21(16): 9843-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24777324

RESUMO

Many polluted sites are typically characterized by contamination with multiple heavy metals, drought, salinity, and nutrient deficiencies. Here, an Australian native succulent halophytic plant species, Carpobrotus rossii (Haw.) Schwantes (Aizoaceae) was investigated to assess its tolerance and phytoextraction potential of Cd, Zn, and the combination of Cd and Zn, when plants were grown in soils spiked with various concentrations of Cd (20-320 mg kg(-1) Cd), Zn (150-2,400 mg kg(-1) Zn) or Cd + Zn (20 + 150, 40 + 300, 80 + 600 mg kg(-1)). The concentration of Cd in plant parts followed the order of roots > stems > leaves, resulting in Cd translocation factor (TF, concentration ratio of shoots to roots) less than one. In contrast, the concentration of Zn was in order of leaves > stems > roots, with a Zn TF greater than one. However, the amount of Cd and Zn were distributed more in leaves than in stems or roots, which was attributed to higher biomass of leaves than stems or roots. The critical value that causes 10% shoot biomass reduction was 115 µg g(-1) for Cd and 1,300 µg g(-1) for Zn. The shoot Cd uptake per plant increased with increasing Cd addition while shoot Zn uptake peaked at 600 mg kg(-1) Zn addition. The combined addition of Cd and Zn reduced biomass production more than Cd or Zn alone and significantly increased Cd concentration, but did not affect Zn concentration in plant parts. The results suggest that C. rossii is able to hyperaccumulate Cd and can be a promising candidate for phytoextraction of Cd from polluted soils.


Assuntos
Aizoaceae/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Austrália
13.
Mol Hum Reprod ; 20(3): 185-99, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24043694

RESUMO

Emerging data suggest that mechanisms to evade the human immune system may be shared by the conceptus, tumour cells, persistent pathogens and viruses. It is therefore timely to revisit the human fetoembryonic defense system (Hu-FEDS) hypothesis that was proposed in two papers in the 1990s. The initial paper suggested that glycoconjugates expressed in the human reproductive system inhibited immune responses directed against gametes and the developing human by employing their carbohydrate sequences as functional groups. These glycoconjugates were proposed to block specific binding interactions and interact with lectins linked to signal transduction pathways that modulated immune cell functions. The second article suggested that aggressive tumour cells and persistent pathogens (HIV, H. pylori, schistosomes) either mimicked or acquired the same carbohydrate functional groups employed in this system to evade immune responses. This subterfuge enabled these pathogens and tumour cells to couple their survival to the human reproductive imperative. The Hu-FEDS model has been repeatedly tested since its inception. Data relevant to this model have also been obtained in other studies. Herein, the Hu-FEDS hypothesis is revisited in the context of these more recent findings. Far more supportive evidence for this model now exists than when it was first proposed, and many of the original predictions have been validated. This type of subterfuge by pathogens and tumour cells likely applies to all sexually reproducing metazoans that must protect their gametes from immune responses. Intervention in these pathological states will likely remain problematic until this system of immune evasion is fully understood and appreciated.


Assuntos
Evasão da Resposta Imune , Neoplasias/imunologia , Polissacarídeos/imunologia , Reprodução/imunologia , Espermatozoides/imunologia , Animais , Feminino , Feto/imunologia , HIV/química , HIV/imunologia , Helicobacter pylori/química , Helicobacter pylori/imunologia , Interações Hospedeiro-Patógeno , Humanos , Tolerância Imunológica , Masculino , Neoplasias/química , Neoplasias/patologia , Polissacarídeos/química , Gravidez , Schistosoma/química , Schistosoma/imunologia , Espermatozoides/química
14.
Front Immunol ; 4: 26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23407606

RESUMO

Like other mucosal surfaces (e.g., the gastrointestinal tract, the respiratory tract), the human female reproductive tract acts as an initial barrier to foreign antigens. In this role, the epithelial surface and subepithelial immune cells must balance protection against pathogenic insults against harmful inflammatory reactions and acceptance of particular foreign antigens. Two common examples of these acceptable foreign antigens are the fetal allograft and human semen/sperm. Both are purposely deposited into the female genital tract and appropriate immunologic response to these non-self antigens is essential to the survival of the species. In light of the weight of this task, it is not surprising that multiple, redundant and overlapping mechanisms are involved. For instance, cells at the immunologic interface between self (female reproductive tract epithelium) and non-self (placental trophoblast cells or human sperm) express glycosylation patterns that mimic those on many metastatic cancer cells and successful pathogens. The cytokine/chemokine milieu at this interface is altered through endocrine and immunologic mechanisms to favor tolerance of non-self. The "foreign" cells themselves also play an integral role in their own immunologic acceptance, since sperm and placental trophoblast cells are unusual and unique in their antigen presenting molecule expression patterns. Here, we will discuss these and other mechanisms that allow the human female reproductive tract to perform this delicate and indispensible balancing act.

15.
Hum Reprod ; 28(3): 566-77, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23315069

RESUMO

STUDY QUESTION: What is the role of carbohydrates in the binding of human sperm to the zona pellucida (ZP) and what are potential implications for pathogenesis? SUMMARY ANSWER: Both lectin-like and protein-protein interactions play an essential role in human gamete interactions. WHAT IS KNOWN ALREADY: Studies in the mouse and human indicate a role for both lectin-like and protein-protein interactions during sperm binding to the ZP. STUDY DESIGN, SIZE, DURATION: Non-systematic literature review. MAIN RESULTS AND THE ROLE OF CHANCE: Ultrasensitive analysis by mass spectrometry of glycans linked to the human ZP has confirmed that this matrix is coated with a high density of complex type N-glycans terminated with the sialyl-Lewis(x) (sLe(x)) sequence, the universal selectin ligand. Selectins are essential for lymphocyte homing, and they participate in the initial binding of circulating leukocytes to activated endothelium at the sites of infection and tissue injury. Subsequent inhibition studies confirmed that either the sLe(x) tetrasaccharide or neoglycoproteins terminated with this sequence inhibited human sperm-ZP binding by 70% in the hemizona assay. These results support the hypothesis that both lectin-like and protein-protein interactions play an essential role in human gamete interactions. The sLe(x) sequence is also a ligand for siglec-9, a lectin-bearing immunoreceptor tyrosine-based inhibitory motif that transmits inhibitory signals. This siglec is expressed on a wide variety of different types of human leukocytes and lymphocytes. This result is consistent with the hypothesis that human ZP glycans are also being employed for immune recognition of the egg and the histoincompatible embryo prior to blastocyst hatching. LIMITATIONS, REASONS FOR CAUTION: This field of study is complex and more experimental work is needed to reveal fully the mechanism of sperm-ZP binding and how it varies between species. WIDER IMPLICATIONS OF THE FINDINGS: Knowledge about the glycans involved in sperm-egg binding may be relevant to infertility due to fertilization failure and also to the mother's immune tolerance of the preimplantation embryo. STUDY FUNDING/COMPETING INTEREST(S): Studies focused on human sperm-egg interactions carried out by the author and coworkers have been supported by the Life Sciences Mission Enhancement Reproductive Biology Program funded by the State of Missouri, a Research Board Grant (CB000500) supported by the University of Missouri System and a grant from the Jeffress Memorial Trust of Virginia. Support from the Breeden-Adams Foundation has also been obtained to investigate potential linkages to tumor evasion. The author has no conflict of interest to declare.


Assuntos
Lectinas/metabolismo , Interações Espermatozoide-Óvulo , Animais , Antígenos CD/metabolismo , Feminino , Humanos , Masculino , Modelos Biológicos , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo , Selectinas/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Antígeno Sialil Lewis X , Zona Pelúcida/imunologia , Zona Pelúcida/metabolismo
16.
Mol Cell Proteomics ; 11(1): M111.008730, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21986992

RESUMO

DC-SIGN is an immune C-type lectin that is expressed on both immature and mature dendritic cells associated with peripheral and lymphoid tissues in humans. It is a pattern recognition receptor that binds to several pathogens including HIV-1, Ebola virus, Mycobacterium tuberculosis, Candida albicans, Helicobacter pylori, and Schistosoma mansoni. Evidence is now mounting that DC-SIGN also recognizes endogenous glycoproteins, and that such interactions play a major role in maintaining immune homeostasis in humans and mice. Autoantigens (neoantigens) are produced for the first time in the human testes and other organs of the male urogenital tract under androgenic stimulus during puberty. Such antigens trigger autoimmune orchitis if the immune response is not tightly regulated within this system. Endogenous ligands for DC-SIGN could play a role in modulating such responses. Human seminal plasma glycoproteins express a high level of terminal Lewis(x) and Lewis(y) carbohydrate antigens. These epitopes react specifically with the lectin domains of DC-SIGN. However, because the expression of these sequences is necessary but not sufficient for interaction with DC-SIGN, this study was undertaken to determine if any seminal plasma glycoproteins are also endogenous ligands for DC-SIGN. Glycoproteins bearing terminal Lewis(x) and Lewis(y) sequences were initially isolated by lectin affinity chromatography. Protein sequencing established that three tumor biomarker glycoproteins (clusterin, galectin-3 binding glycoprotein, prostatic acid phosphatase) and protein C inhibitor were purified by using this affinity method. The binding of DC-SIGN to these seminal plasma glycoproteins was demonstrated in both Western blot and immunoprecipitation studies. These findings have confirmed that human seminal plasma contains endogenous glycoprotein ligands for DC-SIGN that could play a role in maintaining immune homeostasis both in the male urogenital tract and the vagina after coitus.


Assuntos
Moléculas de Adesão Celular/metabolismo , Glicoproteínas/metabolismo , Lectinas Tipo C/metabolismo , Receptores de Superfície Celular/metabolismo , Sêmen/metabolismo , Humanos , Ligantes , Masculino , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
17.
PLoS One ; 6(12): e29011, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22205989

RESUMO

Protein C inhibitor (PCI) is a serpin type of serine protease inhibitor that is found in many tissues and fluids in human, including blood plasma, seminal plasma and urine. This inhibitor displays an unusually broad protease specificity compared with other serpins. Previous studies have shown that the N-glycan(s) and the NH2-terminus affect some blood-related functions of PCI. In this study, we have for the first time determined the N-glycan profile of seminal plasma PCI, by mass spectrometry. The N-glycan structures differed markedly compared with those of both blood-derived and urinary PCI, providing evidence that the N-glycans of PCI are expressed in a tissue-specific manner. The most abundant structure (m/z 2592.9) had a composition of Fuc3Hex5HexNAc4, consistent with a core fucosylated bi-antennary glycan with terminal Lewis(x). A major serine protease in semen, prostate specific antigen (PSA), was used to evaluate the effects of N-glycans and the NH2-terminus on a PCI function related to the reproductive tract. Second-order rate constants for PSA inhibition by PCI were 4.3±0.2 and 4.1±0.5 M⁻¹ s⁻¹ for the natural full-length PCI and a form lacking six amino acids at the NH2-terminus, respectively, whereas these constants were 4.8±0.1 and 29±7 M⁻¹ s⁻¹ for the corresponding PNGase F-treated forms. The 7-8-fold higher rate constants obtained when both the N-glycans and the NH2-terminus had been removed suggest that these structures jointly affect the rate of PSA inhibition, presumably by together hindering conformational changes of PCI required to bind to the catalytic pocket of PSA.


Assuntos
Regulação da Expressão Gênica , Polissacarídeos , Inibidor da Proteína C/química , Inibidor da Proteína C/metabolismo , Humanos , Masculino , Modelos Moleculares , Especificidade de Órgãos , Antígeno Prostático Específico/antagonistas & inibidores , Antígeno Prostático Específico/química , Antígeno Prostático Específico/metabolismo , Inibidor da Proteína C/sangue , Inibidor da Proteína C/farmacologia , Conformação Proteica , Sêmen/metabolismo
18.
Am J Med Genet A ; 155A(9): 2071-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21834044

RESUMO

Polymicrogyria is a disorder of neuronal development resulting in structurally abnormal cerebral hemispheres characterized by over-folding and abnormal lamination of the cerebral cortex. Polymicrogyria is frequently associated with severe neurologic deficits including intellectual disability, motor problems, and epilepsy. There are acquired and genetic causes of polymicrogyria, but most patients with a presumed genetic etiology lack a specific diagnosis. Here we report using whole-exome sequencing to identify compound heterozygous mutations in the WD repeat domain 62 (WDR62) gene as the cause of recurrent polymicrogyria in a sibling pair. Sanger sequencing confirmed that the siblings both inherited 1-bp (maternal allele) and 2-bp (paternal allele) frameshift deletions, which predict premature truncation of WDR62, a protein that has a role in early cortical development. The probands are from a non-consanguineous family of Northern European descent, suggesting that autosomal recessive PMG due to compound heterozygous mutation of WDR62 might be a relatively common cause of PMG in the population. Further studies to identify mutation frequency in the population are needed.


Assuntos
Anormalidades Múltiplas/genética , Exoma , Malformações do Desenvolvimento Cortical/genética , Proteínas do Tecido Nervoso/genética , Adulto , Sequência de Bases , Proteínas de Ciclo Celular , Criança , Anormalidades Craniofaciais/genética , Feminino , Mutação da Fase de Leitura , Testes Genéticos , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imageamento por Ressonância Magnética , Masculino , Mutação , Análise de Sequência de DNA , Deleção de Sequência , Irmãos
19.
J Natl Cancer Inst ; 101(21): 1453-63, 2009 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-19855077

RESUMO

A workshop sponsored by the National Cancer Institute and the US Food and Drug Administration addressed past lessons learned and ongoing challenges faced in biomarker development and drug and biomarker codevelopment. Participants agreed that critical decision points in the product life cycle depend on the level of understanding of the biology of the target and its interaction with the drug, the preanalytical and analytical factors affecting biomarker assay performance, and the clinical disease process. The more known about the biology and the greater the strength of association between an analytical signal and clinical result, the more efficient and less risky the development process will be. Rapid entry into clinical practice will only be achieved by using a rigorous scientific approach, including careful specimen collection and standardized and quality-controlled data collection. Early interaction with appropriate regulatory bodies will ensure studies are appropriately designed and biomarker test performance is well characterized.


Assuntos
Antineoplásicos , Biomarcadores Tumorais , Desenho de Fármacos , Neoplasias/química , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Antineoplásicos/farmacologia , Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Receptores ErbB/análise , Receptores ErbB/antagonistas & inibidores , Estudos de Viabilidade , Feminino , Regulação Neoplásica da Expressão Gênica , Genes erbB-2/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , National Cancer Institute (U.S.) , Valor Preditivo dos Testes , Receptor ErbB-2/análise , Manejo de Espécimes , Trastuzumab , Estados Unidos , United States Food and Drug Administration , Regulação para Cima
20.
J Med Entomol ; 46(2): 335-41, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19351085

RESUMO

Mosquitoes that transmit human diseases are of major importance to the international public health community. Pesticides remain a major component of integrated programs to control these medically important species. However, very few types of pesticides are currently registered for mosquito control. A high-throughput screening method using first-instar larvae of Aedes aegypti was created and evaluated in our laboratory to quickly screen large numbers of chemicals for activity against mosquitoes. LC50 values of a representative group of compounds were determined using this high-throughput screening method and compared with LD50 values determined by topical application against female adults of Ae. aegypti. Our results show that this high-throughput screening method is suitable for screening large numbers of candidate chemicals quickly to identify effective compounds.


Assuntos
Aedes , Inseticidas/análise , Controle de Mosquitos , Testes de Toxicidade/métodos , Animais , Larva , Dose Letal Mediana
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