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1.
Ann Surg Oncol ; 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35378634

RESUMO

BACKGROUND: The Neoadjuvant Breast Symphony Trial (NBRST) demonstrated the 70-gene risk of distant recurrence signature, MammaPrint, and the 80-gene molecular subtyping signature, BluePrint, precisely determined preoperative pathological complete response (pCR) in breast cancer patients. We report 5-year follow-up results in addition to an exploratory analysis by age and menopausal status. METHODS: The observational, prospective NBRST (NCT01479101) included 954 early-stage breast cancer patients aged 18-90 years who received neoadjuvant chemotherapy and had clinical and genomic data available. Chemosensitivity and 5-year distant metastasis-free survival (DMFS) and overall survival (OS) were assessed. In a post hoc subanalysis, results were stratified by age (≤ 50 vs. > 50 years) and menopausal status in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) tumors. RESULTS: MammaPrint and BluePrint further classified 23% of tumors to a different subtype compared with immunohistochemistry, with more precise correspondence to pCR rates. Five-year DMFS and OS were highest in MammaPrint Low Risk, Luminal A-type and HER2-type tumors, and lowest in MammaPrint High Risk, Luminal B-type and Basal-type tumors. There was no significant difference in chemosensitivity between younger and older patients with Low-Risk (2.2% vs. 3.8%; p = 0.64) or High-Risk tumors (14.5% vs. 11.5%; p = 0.42), or within each BluePrint subtype; this was similar when stratifying by menopausal status. The 5-year outcomes were comparable by age or menopausal status for each molecular subtype. CONCLUSION: Intrinsic preoperative chemosensitivity and long-term outcomes were precisely determined by BluePrint and MammaPrint regardless of patient age, supporting the utility of these assays to inform treatment and surgical decisions in early-stage breast cancer.

2.
J Cell Sci ; 131(10)2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29678905

RESUMO

X-linked inhibitor of apoptosis (XIAP) plays an important role in preventing apoptotic cell death. XIAP has been shown to participate in signaling pathways, including Wnt signaling. XIAP regulates Wnt signaling by promoting the monoubiquitylation of the co-repressor Groucho/TLE family proteins, decreasing its affinity for the TCF/Lef family of transcription factors and allowing assembly of transcriptionally active ß-catenin-TCF/Lef complexes. We now demonstrate that XIAP is phosphorylated by GSK3 at threonine 180, and that an alanine mutant (XIAPT180A) exhibits decreased Wnt activity compared to wild-type XIAP in cultured human cells and in Xenopus embryos. Although XIAPT180A ubiquitylates TLE3 at wild-type levels in vitro, it exhibits a reduced capacity to ubiquitylate and bind TLE3 in human cells. XIAPT180A binds Smac (also known as DIABLO) and inhibits Fas-induced apoptosis to a similar degree to wild-type XIAP. Our studies uncover a new mechanism by which XIAP is specifically directed towards a Wnt signaling function versus its anti-apoptotic function. These findings have implications for development of anti-XIAP therapeutics for human cancers.


Assuntos
Treonina/metabolismo , Proteína Wnt3A/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/química , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Motivos de Aminoácidos , Animais , Proteínas Reguladoras de Apoptose , Linhagem Celular , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fosforilação , Ligação Proteica , Via de Sinalização Wnt , Proteína Wnt3A/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Xenopus
3.
Mol Cell ; 45(5): 619-28, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22304967

RESUMO

A key event in Wnt signaling is conversion of TCF/Lef from a transcriptional repressor to an activator, yet how this switch occurs is not well understood. Here, we report an unanticipated role for X-linked inhibitor of apoptosis (XIAP) in regulating this critical Wnt signaling event that is independent of its antiapoptotic function. We identified DIAP1 as a positive regulator of Wingless signaling in a Drosophila S2 cell-based RNAi screen. XIAP, its vertebrate homolog, is similarly required for Wnt signaling in cultured mammalian cells and in Xenopus embryos, indicating evolutionary conservation of function. Upon Wnt pathway activation, XIAP is recruited to TCF/Lef where it monoubiquitylates Groucho (Gro)/TLE. This modification decreases affinity of Gro/TLE for TCF/Lef. Our data reveal a transcriptional switch involving XIAP-mediated ubiquitylation of Gro/TLE that facilitates its removal from TCF/Lef, thus allowing ß-catenin-TCF/Lef complex assembly and initiation of a Wnt-specific transcriptional program.


Assuntos
Proteínas Correpressoras/metabolismo , Drosophila/metabolismo , Embrião não Mamífero/metabolismo , Ubiquitinação , Via de Sinalização Wnt , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/fisiologia , Animais , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/fisiologia , Células HEK293 , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Inibidoras de Apoptose/fisiologia , Modelos Genéticos , Interferência de RNA , Proteínas Wnt/metabolismo , Proteína Wnt1/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Xenopus , Proteínas de Xenopus/metabolismo
4.
Transfusion ; 58(5): 1157-1162, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29479723

RESUMO

BACKGROUND: The Kidd-null phenotype, Jk(a-b-), occurs in individuals who do not express the JK glycoprotein. Jk(a-b-) individuals can make an antibody against the Jk3 antigen, a high-incidence antigen present in more than 99.9% of most populations. This presents many challenges to the blood bank including identification of the antibody, masking of other antibodies, and how to provide transfusion support given the rarity of Jk3-negative blood products. Kidd antibodies may cause acute and delayed hemolytic reactions as well as hemolytic disease of the fetus and newborn (HDFN). In this article, we present a series of four practical cases of pregnant women with the anti-Jk3 alloantibody that demonstrate a range of clinical presentations of Kidd-related HDFN. STUDY DESIGN AND METHODS: We retrospectively reviewed the clinical and blood bank records for four patients and their newborns encountered at institutions in Tennessee, Missouri, Hawaii, and Guam with an anti-Jk3 identified during pregnancy. RESULTS: Two cases showed no significant evidence for HDFN, while two cases were of mild-to-moderate severity requiring early delivery due to elevated middle cerebral artery (MCA) flow velocities but requiring only phototherapy for hyperbilirubinemia. No intrauterine or neonatal transfusions were necessary. Anti-Jk3 alloantibody titers ranged from 2 to 128. CONCLUSION: Clinical manifestations of anti-Jk3 HDFN are generally mild to moderate. Anti-Jk3 titers were not found to correlate directly with HDFN severity. We suggest a titer of 16 to 32 as a cutoff for implementing enhanced monitoring of fetal MCA flow velocities, as such titers may be indicative of elevated HDFN risk.


Assuntos
Antígenos de Grupos Sanguíneos/imunologia , Eritroblastose Fetal/diagnóstico , Isoanticorpos/análise , Sistema do Grupo Sanguíneo Kidd/imunologia , Adulto , Armazenamento de Sangue/métodos , Feminino , Humanos , Recém-Nascido , Isoantígenos , Artéria Cerebral Média/fisiopatologia , Gravidez , Estudos Retrospectivos , Risco
5.
J Cell Sci ; 128(6): 1204-16, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25616898

RESUMO

Proper kinetochore recruitment and regulation of dynein and the Mad1-Mad2 complex requires the Rod-Zw10-Zwilch (RZZ) complex. Here, we describe rod(Z3), a maternal-effect Drosophila mutation changing a single residue in the Rough Deal (Rod) subunit of RZZ. Although the RZZ complex containing this altered subunit (denoted R(Z3)ZZ) is present in early syncytial stage embryos laid by homozygous rod(Z3) mothers, it is not recruited to kinetochores. Consequently, the embryos have no spindle assembly checkpoint (SAC), and syncytial mitoses are profoundly perturbed. The polar body (residual meiotic products) cannot remain in its SAC-dependent metaphase-like state, and decondenses into chromatin. In neuroblasts of homozygous rod(Z3) larvae, R(Z3)ZZ recruitment is only partially reduced, the SAC is functional and mitosis is relatively normal. R(Z3)ZZ nevertheless behaves abnormally: it does not further accumulate on kinetochores when microtubules are depolymerized; it reduces the rate of Mad1 recruitment; and it dominantly interferes with the dynein-mediated streaming of RZZ from attached kinetochores. These results suggest that the mutated residue of rod(Z3) is required for normal RZZ kinetochore recruitment and function and, moreover, that the RZZ recruitment pathway might differ in syncytial stage embryos and post-embryonic somatic cells.


Assuntos
Animais Geneticamente Modificados/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Cinetocoros/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação/genética , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados/embriologia , Animais Geneticamente Modificados/genética , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Feminino , Processamento de Imagem Assistida por Computador , Dados de Sequência Molecular , Neurônios/citologia , Neurônios/metabolismo , Homologia de Sequência de Aminoácidos , Fuso Acromático/fisiologia
6.
Development ; 141(6): 1332-41, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24553286

RESUMO

We previously identified a Drosophila maternal effect-lethal mutant named 'no poles' (nopo). Embryos from nopo females undergo mitotic arrest with barrel-shaped, acentrosomal spindles during the rapid cycles of syncytial embryogenesis because of activation of a Chk2-mediated DNA checkpoint. NOPO is the Drosophila homolog of human TNF receptor associated factor (TRAF)-interacting protein (TRIP), which has been implicated in TNF signaling. NOPO and TRIP contain RING domains closely resembling those of known E3 ubiquitin ligases. We herein sought to elucidate the mechanism by which TRIP/NOPO promotes genomic stability by performing a yeast two-hybrid screen to identify potential substrates/interactors. We identified members of the Y-family of DNA polymerases that facilitate replicative bypass of damaged DNA (translesion synthesis) as TRIP interactors. We show that TRIP and NOPO co-immunoprecipitate with human and Drosophila Polη, respectively, from cultured cells. We generated a null mutation in Drosophila Polη (dPolη) and found that dPolη-derived embryos have increased sensitivity to ultraviolet irradiation and exhibit nopo-like mitotic spindle defects. dPolη and nopo interact genetically in that overexpression of dPolη in hypomorphic nopo-derived embryos suppresses nopo phenotypes. We observed enhanced ubiquitylation of Polη by TRIP and NOPO E3 ligases in human cells and Drosophila embryos, respectively, and show that TRIP promotes hPolη localization to nuclear foci in human cells. We present a model in which TRIP/NOPO ubiquitylates Polη to positively regulate its activity in translesion synthesis.


Assuntos
DNA Polimerase Dirigida por DNA/metabolismo , Proteínas de Drosophila/metabolismo , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Animais Geneticamente Modificados , Dano ao DNA , DNA Polimerase Dirigida por DNA/deficiência , DNA Polimerase Dirigida por DNA/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Instabilidade Genômica , Células HeLa , Humanos , Modelos Biológicos , Mutação , Transdução de Sinais , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genética , Técnicas do Sistema de Duplo-Híbrido , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
7.
Ann Surg Oncol ; 24(9): 2539-2546, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28447218

RESUMO

BACKGROUND: Pertuzumab became a standard part of neoadjuvant therapy for human epidermal growth factor receptor 2-positive (HER2+) breast cancers approximately halfway through Neoadjuvant Breast Registry Symphony Trial (NBRST) enrollment, providing a unique opportunity to determine biologically which clinical HER2+ patients benefit most from dual targeting. As a neoadjuvant phase 4 study, NBRST classifies patients by both conventional and molecular subtyping. METHODS: Of 308 clinical HER2+ patients enrolled in NBRST between 2011 and 2014 from 62 U.S. institutions, 297 received neoadjuvant chemotherapy (NCT) with HER2-targeted therapy and underwent surgery. This study compared the pathologic complete response (pCR) rate of BluePrint versus clinical subtypes with treatment, specifically differences between trastuzumab (T) treatment and trastuzumab and pertuzumab (T/P) treatment. RESULTS: In this study, 60% of the patients received NCT-T, and 40% received NCT-T/P. The overall pCR rate (ypT0/isN0) was 47%. BluePrint classified 161 tumors (54%) as HER2 type, with a pCR rate of 65%. This was significantly higher than the pCR rate for the 91 HER2+ tumors (31%) classified as luminal (18%) (p = 0.00001) and the 45 tumors (15%) classified as basal (44%) (p = 0.0166). The patients treated with T/P had higher pCR rates than those treated with trastuzumab alone. The difference was most pronounced in the BluePrint luminal patients (8 vs. 31%). The highest pCR was reached by the BluePrint HER2-type patients treated with T/P (76%). CONCLUSIONS: The addition of pertuzumab leads to increased pCR rates for all HER2+ patient groups except for the BluePrint basal-type patients. This better response was most pronounced for the BluePrint luminal-type patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Receptor ErbB-2/metabolismo , Trastuzumab/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Testes Genéticos , Genômica , Humanos , Terapia Neoadjuvante , Estudos Prospectivos , Trastuzumab/administração & dosagem , Resultado do Tratamento
8.
Ann Surg Oncol ; 24(3): 669-675, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27770345

RESUMO

PURPOSE: Hormone receptor-positive (HR+) tumors have heterogeneous biology and present a challenge for determining optimal treatment. In the Neoadjuvant Breast Registry Symphony Trial (NBRST) patients were classified according to MammaPrint/BluePrint subtyping to provide insight into the response to neoadjuvant endocrine therapy (NET) or neoadjuvant chemotherapy (NCT). OBJECTIVE: The purpose of this predefined substudy was to compare MammaPrint/BluePrint with conventional 'clinical' immunohistochemistry/fluorescence in situ hybridization (IHC/FISH) subtyping in 'clinical luminal' [HR+/human epidermal growth factor receptor 2-negative (HER2-)] breast cancer patients to predict treatment sensitivity. METHODS: NBRST IHC/FISH HR+/HER2- breast cancer patients (n = 474) were classified into four molecular subgroups by MammaPrint/BluePrint subtyping: Luminal A, Luminal B, HER2, and Basal type. Pathological complete response (pCR) rates were compared with conventional IHC/FISH subtype. RESULTS: The overall pCR rate for 'clinical luminal' patients to NCT was 11 %; however, 87 of these 474 patients were reclassified as Basal type by BluePrint, with a high pCR rate of 32 %. The MammaPrint index was highly associated with the likelihood of pCR (p < 0.001). Fifty-three patients with BluePrint Luminal tumors received NET with an aromatase inhibitor and 36 (68 %) had a clinical response. CONCLUSIONS: With BluePrint subtyping, 18 % of clinical 'luminal' patients are classified in a different subgroup, compared with conventional assessment, and these patients have a significantly higher response rate to NCT compared with BluePrint Luminal patients. MammaPrint/BluePrint subtyping can help allocate effective treatment to appropriate patients. In addition, accurate identification of subtype biology is important in the interpretation of neoadjuvant treatment response since lack of pCR in luminal patients does not portend the worse prognosis associated with residual disease in Basal and HER2 subtypes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/classificação , Neoplasias da Mama/tratamento farmacológico , Perfilação da Expressão Gênica , Tipagem Molecular/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastrozol , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Quimioterapia Adjuvante , Tomada de Decisão Clínica , Ciclofosfamida/administração & dosagem , Docetaxel , Doxorrubicina/administração & dosagem , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Letrozol , Mastectomia Segmentar , Pessoa de Meia-Idade , Terapia Neoadjuvante , Nitrilas/administração & dosagem , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Sistema de Registros , Tamoxifeno/administração & dosagem , Taxoides/administração & dosagem , Resultado do Tratamento , Triazóis/administração & dosagem , Adulto Jovem
9.
Ann Surg Oncol ; 23(5): 1522-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26714960

RESUMO

BACKGROUND: The prospective Neoadjuvant Breast Symphony Trial (NBRST) study found that MammaPrint/BluePrint functional molecular subtype is superior to conventional immunohistochemistry/fluorescence in situ hybridization subtyping for predicting pathologic complete response (pCR) to neoadjuvant chemotherapy. The purpose of this substudy was to determine if the rate of pCR is affected by tumor size. METHODS: The NBRST study includes breast cancer patients who received neoadjuvant chemotherapy. MammaPrint/BluePrint subtyping classified patients into four molecular subgroups: Luminal A, Luminal B, HER2 (human epidermal growth factor receptor 2), and Basal type. Probability of pCR (ypT0/isN0) as a function of tumor size and molecular subgroup was evaluated. RESULTS: A total of 608 patients were evaluable with overall pCR rates of 28.5 %. Luminal A and B patients had significantly lower rates of pCR (6.1 and 8.7 %, respectively) than either basal (37.1 %) or HER2 (55.0 %) patients (p < 0.001). The probability of pCR significantly decreased with tumor size >5 cm [p = 0.022, odds ratio (OR) 0.58, 95 % confidence interval (CI) 0.36, 0.93]. This relationship was statistically significant in the Basal (p = 0.026, OR 0.46, 95 % CI 0.23, 0.91) and HER2 (p = 0.039, OR 0.36, 95 % CI 0.14, 0.95) subgroups. In multivariate logistic regression analyses, the dichotomized tumor size variable was not significant in any of the molecular subgroups. DISCUSSION: Even though tumor size would intuitively be a clinical determinant of pCR, the current analysis showed that the adjusted OR for tumor size was not statistically significant in any of the molecular subgroups. Factors significantly associated with pCR were PR status, grade, lymph node status, and BluePrint molecular subtyping, which had the strongest correlation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Indução de Remissão , Taxa de Sobrevida , Carga Tumoral , Adulto Jovem
10.
Dev Biol ; 386(1): 42-52, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24333177

RESUMO

We previously showed that asunder (asun) is a critical regulator of dynein localization during Drosophila spermatogenesis. Because the expression of asun is much higher in Drosophila ovaries and early embryos than in testes, we herein sought to determine whether ASUN plays roles in oogenesis and/or embryogenesis. We characterized the female germline phenotypes of flies homozygous for a null allele of asun (asun(d93)). We find that asun(d93) females lay very few eggs and contain smaller ovaries with a highly disorganized arrangement of ovarioles in comparison to wild-type females. asun(d93) ovaries also contain a significant number of egg chambers with structural defects. A majority of the eggs laid by asun(d93) females are ventralized to varying degrees, from mild to severe; this ventralization phenotype may be secondary to defective localization of gurken transcripts, a dynein-regulated step, within asun(d93) oocytes. We find that dynein localization is aberrant in asun(d93) oocytes, indicating that ASUN is required for this process in both male and female germ cells. In addition to the loss of gurken mRNA localization, asun(d93) ovaries exhibit defects in other dynein-mediated processes such as migration of nurse cell centrosomes into the oocyte during the early mitotic divisions, maintenance of the oocyte nucleus in the anterior-dorsal region of the oocyte in late-stage egg chambers, and coupling between the oocyte nucleus and centrosomes. Taken together, our data indicate that asun is a critical regulator of dynein localization and dynein-mediated processes during Drosophila oogenesis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Oogênese/genética , Alelos , Animais , Padronização Corporal , Linhagem da Célula , Núcleo Celular/metabolismo , Centrossomo/metabolismo , Dineínas/metabolismo , Feminino , Genótipo , Homozigoto , Hibridização In Situ , Masculino , Oócitos/metabolismo , Ovário/metabolismo , Fenótipo , Fatores Sexuais , Testículo/metabolismo , Transgenes
11.
Development ; 139(16): 2945-54, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22764052

RESUMO

Dynein, a microtubule motor complex, plays crucial roles in cell-cycle progression in many systems. The LIS1 accessory protein directly binds dynein, although its precise role in regulating dynein remains unclear. Mutation of human LIS1 causes lissencephaly, a developmental brain disorder. To gain insight into the in vivo functions of LIS1, we characterized a male-sterile allele of the Drosophila homolog of human LIS1. We found that centrosomes do not properly detach from the cell cortex at the onset of meiosis in most Lis-1 spermatocytes; centrosomes that do break cortical associations fail to attach to the nucleus. In Lis-1 spermatids, we observed loss of attachments between the nucleus, basal body and mitochondria. The localization pattern of LIS-1 protein throughout Drosophila spermatogenesis mirrors that of dynein. We show that dynein recruitment to the nuclear surface and spindle poles is severely reduced in Lis-1 male germ cells. We propose that Lis-1 spermatogenesis phenotypes are due to loss of dynein regulation, as we observed similar phenotypes in flies null for Tctex-1, a dynein light chain. We have previously identified asunder (asun) as another regulator of dynein localization and centrosome positioning during Drosophila spermatogenesis. We now report that Lis-1 is a strong dominant enhancer of asun and that localization of LIS-1 in male germ cells is ASUN dependent. We found that Drosophila LIS-1 and ASUN colocalize and coimmunoprecipitate from transfected cells, suggesting that they function within a common complex. We present a model in which Lis-1 and asun cooperate to regulate dynein localization and centrosome positioning during Drosophila spermatogenesis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Dineínas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Espermatogênese/fisiologia , Animais , Animais Geneticamente Modificados , Proteínas de Ciclo Celular/genética , Centrossomo/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Complexo Dinactina , Dineínas/genética , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/genética , Modelos Biológicos , Fenótipo , Espermátides/metabolismo , Espermátides/ultraestrutura , Espermatócitos/metabolismo , Espermatócitos/ultraestrutura , Espermatogênese/genética
12.
Biomater Sci ; 12(5): 1307-1319, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38263852

RESUMO

Around 33% of the global population suffers from non-alcoholic fatty liver disease (NAFLD). From these patients, 30% of them progress into non-alcoholic steatohepatitis (NASH), the critical point where lack of treatment leads to cirrhosis and hepatic failure. Moreover, to date, there are no approved therapeutic options available for NASH. It is known that hepatic stellate cell (HSC) activation contributes the most to hepatic disfunction, leading to reactive oxygen species (ROS) accumulation and chronic inflammation, and that the use of nanomaterials to deliver antioxidants may have potential to reduce the activity of activated HSCs. Therefore, we implemented a human in vitro co-culture model in which we take into consideration two factors related to NASH and fibrosis: human hepatic stellate cells from a NASH diagnosed donor (HHSC-N) and peripheral blood mononuclear cells (PBMCs), particularly lymphocytes. The co-cultures were treated with: (1) carbon quantum dots (CD) or (2) lactoferrin conjugated CD (CD-LF) for 24 h or 72 h. CD and CD-LF treatments significantly downregulated profibrotic genes' expression levels of ACTA2, COL1A1, and TIMP1 in co-cultured HHSC-N at 72 h. Also, we assayed the inflammatory response by quantifying the concentrations of cytokines IL-22, IL-10, IFN-γ and IL-4 present in the co-culture's conditioned media whose concentrations may suggest a resolution-associated response in progress. Our findings may serve as a starting point for the development of a NASH treatment using bio-nanotechnology.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Pontos Quânticos , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Células Estreladas do Fígado/metabolismo , Leucócitos Mononucleares/metabolismo , Cirrose Hepática/patologia , Fibrose , Fígado/metabolismo
14.
Nat Chem Biol ; 6(11): 829-36, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20890287

RESUMO

Wnt/ß-catenin signaling is critically involved in metazoan development, stem cell maintenance and human disease. Using Xenopus laevis egg extract to screen for compounds that both stabilize Axin and promote ß-catenin turnover, we identified an FDA-approved drug, pyrvinium, as a potent inhibitor of Wnt signaling (EC(50) of ∼10 nM). We show pyrvinium binds all casein kinase 1 (CK1) family members in vitro at low nanomolar concentrations and pyrvinium selectively potentiates casein kinase 1α (CK1α) kinase activity. CK1α knockdown abrogates the effects of pyrvinium on the Wnt pathway. In addition to its effects on Axin and ß-catenin levels, pyrvinium promotes degradation of Pygopus, a Wnt transcriptional component. Pyrvinium treatment of colon cancer cells with mutation of the gene for adenomatous polyposis coli (APC) or ß-catenin inhibits both Wnt signaling and proliferation. Our findings reveal allosteric activation of CK1α as an effective mechanism to inhibit Wnt signaling and highlight a new strategy for targeted therapeutics directed against the Wnt pathway.


Assuntos
Caseína Quinase Ialfa/metabolismo , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Compostos de Pirvínio/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/metabolismo , Animais , Proteína Axina , Caseína Quinase I/genética , Caseína Quinase I/metabolismo , Extratos Celulares , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Oócitos/citologia , Oócitos/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas Wnt/química , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteínas de Xenopus , Xenopus laevis , beta Catenina/genética , beta Catenina/metabolismo
15.
Bioorg Med Chem ; 20(6): 1869-77, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22261025

RESUMO

Extract prepared from Xenopus eggs represents a cell-free system that has been shown to recapitulate a multitude of cellular processes, including cell cycle regulation, DNA replication/repair, and cytoskeletal dynamics. In addition, this system has been used to successfully reconstitute the Wnt pathway. Xenopus egg extract, which can be biochemically manipulated, offers an ideal medium in which small molecule screening can be performed in near native milieu. Thus, the use of Xenopus egg extract for small molecule screening represents an ideal bridge between targeted and phenotypic screening approaches. This review focuses on the use of this system for small molecules modulators of major signal transduction pathways (Notch, Hedgehog, and Wnt) that are critical for the development of the early Xenopus embryo. We describe the properties of Xenopus egg extract and our own high throughput screen for small molecules that modulate the Wnt pathway using this cell-free system. We propose that Xenopus egg extract could similarly be adapted for screening for modulators of the Notch and Hedgehog pathways.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Óvulo/química , Óvulo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Xenopus laevis/metabolismo , Animais , Proteínas Hedgehog/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Receptores Notch/metabolismo , Bibliotecas de Moléculas Pequenas/química , Via de Sinalização Wnt/efeitos dos fármacos
16.
Mol Genet Genomic Med ; 10(12): e2054, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36106513

RESUMO

BACKGROUND: A de novo, pathogenic, missense variant in UBTF, c.628G>A p.Glu210Lys, has been described as the cause of an emerging neurodegenerative disorder, Childhood-Onset Neurodegeneration with Brain Atrophy (CONDBA). The p.Glu210Lys alteration yields a positively charged stretch of three lysine residues. Functional studies confirmed this change results in a stronger interaction with negatively charged DNA and gain-of-function activity when compared to the wild-type sequence. The CONDBA phenotype reported in association with p.Glu210Lys consists of normal early-neurodevelopment followed by progressive motor, cognitive, and behavioral regression in early-to-middle childhood. METHODS AND RESULTS: The current proband presented at 9 months of age with baseline developmental delay and more extensive neuroradiological findings, including pontine hypoplasia, thalamic volume loss and signal abnormality, and hypomyelination. Like the recurrent CONDBA p.Glu210Lys variant, this novel variant, c.608A>G p.(Gln203Arg) lies within the highly conserved second HMG-box homology domain and involves the replacement of the wild-type residue with a positively charged residue, arginine. Computational structural modeling demonstrates that this amino acid substitution potentiates the interaction between UBTF and DNA, likely resulting in a gain-of-function effect for the UBTF protein, UBF. CONCLUSION: Here we present a new divergent phenotype associated with a novel, likely pathogenic, missense variant at a different position in the UBTF gene, c.608A>G p.(Gln203Arg).


Assuntos
Recidiva Local de Neoplasia , Doenças Neurodegenerativas , Criança , Humanos , Recidiva Local de Neoplasia/patologia , Fenótipo , Atrofia/genética , Atrofia/patologia , Doenças Neurodegenerativas/genética , DNA , Encéfalo/patologia
17.
Surg Oncol ; 45: 101885, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36436423

RESUMO

BACKGROUND: As more patients with early-stage breast cancer receive neoadjuvant endocrine therapy (NET), there is a need for reliable biomarkers that can identify patients with HR+ HER2- tumors who are likely to benefit from NET. NBRST (NCT01479101) compared the prognostic value of the 70-gene risk classification and 80-gene molecular subtyping signatures with conventional pathological classification methods in response to neoadjuvant therapy. We evaluated the association of these signatures with clinical response and 5-year outcome of patients treated with NET. METHODS: 1091 patients with early-stage breast cancer scheduled to receive neoadjuvant therapy were prospectively enrolled into NBRST, and a sub-analysis of 67 patients treated with NET was performed. Patients received standard of care genomic testing using the 70-gene and 80-gene signatures and were treated with NET, per physician's discretion. The primary endpoint was pathologic partial response (pPR) and secondary endpoints were distant metastasis-free survival (DMFS) and overall survival (OS). Clinical benefit was defined as having a pPR or stable disease (SD) with NET. RESULTS: Overall, 94.4% of patients with genomically (g) Luminal A-Type (50.0% pPR and 44.4% SD) and 95.0% with Luminal B-Type tumors (55.0% pPR and 40.0% SD) exhibited clinical benefit. At 5 years, patients with gLuminal B tumors had significantly worse DMFS (75.6%, 95% CI 50.8-89.1) than patients with gLuminal A (91.1%; 95% CI 74.8-97.1; p = 0.047), with a similar trend for OS, albeit not significant (81.0%, 95% CI 56.9-92.4 and 91.1%, 95% CI 74.8-97.1, respectively; p = 0.13). CONCLUSIONS: Genomic assays offer a broader understanding of the underlying tumor biology, which adds precision to pathology as a preoperative risk classifier. Patients with 70-gene signature Low Risk, gLuminal A tumors treated with endocrine therapy alone have excellent 5-year outcomes. Most patients with genomically-defined Luminal A- and B-Type tumors respond well to NET, suggesting these patients may be safely treated with NET, while those with gLuminal B tumors will also require post-operative chemotherapy or CDK4/6 inhibitors to improve long-term outcomes. Overall, these findings demonstrate that genomic classification, defined by the combined 70- and 80-gene signatures, is associated with tumor response and prognostic of long-term outcomes.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Genômica , Prognóstico , Ensaios Clínicos como Assunto
18.
JCO Precis Oncol ; 6: e2200197, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36108259

RESUMO

PURPOSE: The prospective Neoadjuvant Breast Registry Symphony Trial compared the 80-gene molecular subtyping signature with clinical assessment by immunohistochemistry and/or fluorescence in situ hybridization in predicting pathologic complete response (pCR) and 5-year outcomes in patients with early-stage breast cancer. METHODS: Standard-of-care neoadjuvant chemotherapy combined with trastuzumab or trastuzumab plus pertuzumab was given to patients with human epidermal growth factor receptor 2 (HER2)-positive tumors (n = 295). pCR was the primary end point, with secondary end points of distant metastasis-free survival and overall survival at 5 years. RESULTS: Among clinically defined HER2-positive (cHER2) tumors, the 80-gene assay identified 29.5% (87 of 295) as Luminal-Type (cHER2/gLuminal), 14.9% (44 of 295) as Basal-Type (cHER2/gBasal), and 55.6% (164 of 295) as HER2-Type (cHER2/genomically classified as HER2 [gHER2]). Patients with cHER2/gHER2 tumors had a higher pCR rate (61.6%) compared with non-gHER2 tumors (26.7%; P < .001). Dual targeting for cHER2/gHER2 tumors yielded a higher pCR rate (75%) compared with those treated with single HER2-targeted therapy (54%; P = .006). For cHER2/gBasal tumors, the 42.9% pCR rate observed with dual targeting was not different from that with trastuzumab alone (46.4%; P = .830). Among those with cHER2/gBasal tumors, 5-year distant metastasis-free survival (68.6%; 95% CI, 49.1 to 81.9) was significantly worse than in patients with cHER2/gLuminal tumors (88.9%; 95% CI, 78.0 to 94.6) and cHER2/gHER2 tumors (87.4%; 95% CI, 80.2 to 92.2; P = .010), with similar corresponding overall survival differences. CONCLUSION: The 80-gene assay identified meaningful genomic diversity in patients with cHER2 disease. Patients with cHER2/gHER2 tumors, who benefitted most from dual HER2-targeted therapy, accounted for approximately half of the cHER2 cohort. Genomically Luminal tumors had low pCR rates but good 5-year outcomes. cHER2/gBasal tumors derived no benefit from dual therapy and had significantly worse 5-year prognosis; these patients merit special consideration in future trials.


Assuntos
Antineoplásicos , Terapia Neoadjuvante , Antineoplásicos/uso terapêutico , Genômica , Humanos , Hibridização in Situ Fluorescente , Estudos Prospectivos , Receptor ErbB-2 , Trastuzumab/farmacologia
19.
JCO Precis Oncol ; 6: e2100463, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35476550

RESUMO

PURPOSE: The 80-gene molecular subtyping signature (80-GS) reclassifies a proportion of immunohistochemistry (IHC)-defined luminal breast cancers (estrogen receptor-positive [ER+], human epidermal growth factor receptor 2-negative [HER2-]) as Basal-Type. We report the association of 80-GS reclassification with neoadjuvant treatment response and 5-year outcome in patients with breast cancer. METHODS: Neoadjuvant Breast Registry Symphony Trial (NBRST; NCT01479101) is an observational, prospective study that included 1,069 patients with early-stage breast cancer age 18-90 years who received neoadjuvant therapy. Pathologic complete response (pCR) and 5-year distant metastasis-free survival (DMFS) and overall survival (OS) were assessed in 477 patients with IHC-defined ER+, HER2- tumors and in a reference group of 229 patients with IHC-defined triple-negative breast cancer (TNBC). RESULTS: 80-GS reclassified 15% of ER+, HER2- tumors (n = 73) as Basal-Type (ER+/Basal), which had similar pCR compared with TNBC/Basal tumors (34% v 38%; P = .52), and significantly higher pCR than ER+/Luminal A (2%; P < .001) and ER+/Luminal B (6%; P < .001) tumors. The 5-year DMFS (%, [95% CI]) was significantly lower for patients with ER+/Basal tumors (66% [52.6 to 77.3]), compared with those with ER+/Luminal A tumors (92.3% [85.2 to 96.1]) and ER+/Luminal B tumors (73.5% [44.5 to 79.3]). Importantly, patients with ER+/Basal or TNBC/Basal tumors that had a pCR exhibited significantly improved DMFS and OS compared with those with residual disease. By contrast, patients with ER+/Luminal B tumors had comparable 5-year DMFS and OS whether or not they achieved pCR. CONCLUSION: Significant differences in chemosensitivity and 5-year outcome suggest patients with ER+/Basal molecular subtype may benefit from neoadjuvant regimens optimized for patients with TNBC/Basal tumors compared with patients with ER+/Luminal subtype. These data highlight the importance of identifying this subset of patients to improve treatment planning and long-term survival.


Assuntos
Terapia Neoadjuvante , Neoplasias de Mama Triplo Negativas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Receptor ErbB-2 , Receptores de Estrogênio/genética , Receptores de Progesterona/análise , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto Jovem
20.
Nat Commun ; 13(1): 6054, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229431

RESUMO

Oral-facial-digital (OFD) syndromes are a heterogeneous group of congenital disorders characterized by malformations of the face and oral cavity, and digit anomalies. Mutations within 12 cilia-related genes have been identified that cause several types of OFD, suggesting that OFDs constitute a subgroup of developmental ciliopathies. Through homozygosity mapping and exome sequencing of two families with variable OFD type 2, we identified distinct germline variants in INTS13, a subunit of the Integrator complex. This multiprotein complex associates with RNA Polymerase II and cleaves nascent RNA to modulate gene expression. We determined that INTS13 utilizes its C-terminus to bind the Integrator cleavage module, which is disrupted by the identified germline variants p.S652L and p.K668Nfs*9. Depletion of INTS13 disrupts ciliogenesis in human cultured cells and causes dysregulation of a broad collection of ciliary genes. Accordingly, its knockdown in Xenopus embryos leads to motile cilia anomalies. Altogether, we show that mutations in INTS13 cause an autosomal recessive ciliopathy, which reveals key interactions between components of the Integrator complex.


Assuntos
Proteínas de Transporte/genética , Proteínas de Ciclo Celular/genética , Ciliopatias , Síndromes Orofaciodigitais , Cílios/genética , Ciliopatias/genética , Homozigoto , Humanos , Mutação , Síndromes Orofaciodigitais/genética , RNA , RNA Polimerase II/genética
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