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1.
Cancer Immunol Immunother ; 72(7): 2005-2013, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36738310

RESUMO

BACKGROUND AND OBJECTIVES: Medical comorbidities (MC) are highly prevalent among patients with cancer and predict worse outcomes for traditional therapies. This association is poorly understood for checkpoint inhibitor immunotherapy (IO). We aimed to explore the relationship between common MC including cardiovascular disease (CVD), immune-related adverse events (irAEs), and overall survival (OS) among patients receiving IO for advanced cancer. METHODS: This is a retrospective cohort study of 671 patients with any cancer who received IO at our institution from 2011 to 2018. Clinical data were abstracted via chart review and query of ICD-10 codes and used to calculate modified Charlson comorbidity index (mCCI) scores. The primary outcomes were the association of individual MC with irAEs and OS using bivariate and multivariable analyses. Secondary outcomes included association of mCCI score with irAEs and OS. RESULTS: Among 671 patients, 62.1% had a mCCI score ≥ 1. No individual MC were associated with irAEs or OS. Increased CCI score was associated with decreased OS (p < 0.01) but not with irAEs. Grade ≥ 3 irAEs were associated with increased OS among patients without CVD (HR 0.37 [95% CI: 0.25, 0.55], p < 0.01), but not among patients with CVD. CONCLUSIONS: No specific MC predicted risk of irAEs or OS for patients receiving IO. Increased CCI score did not predict risk of irAEs but was associated with shorter OS. This suggests IO is safe for patients with MC, but MC may limit survival benefits of IO. CVD may predict shorter OS in patients with irAEs and should be evaluated among patients receiving IO.


Assuntos
Doenças Cardiovasculares , Neoplasias , Humanos , Estudos Retrospectivos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Neoplasias/tratamento farmacológico , Comorbidade , Imunoterapia/efeitos adversos
2.
Cancer Immunol Immunother ; 69(7): 1177-1187, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32140762

RESUMO

BACKGROUND: Immune-related adverse events (irAEs) comprise a distinct spectrum of auto-inflammatory manifestations triggered due to immune checkpoint inhibitors (ICI). Current data on the association of irAEs with outcomes in NSCLC treated with nivolumab are limited. METHODS AND OBJECTIVES: We pooled data from 531 metastatic NSCLC patients from five centers treated with nivolumab after failing platinum-based chemotherapy. The primary objective was to investigate the relationship between irAEs with clinical benefit to nivolumab as well as to elucidate patterns of irAE-related ICI discontinuations and their impact on survival. RESULTS: 33.0% (173/531) of patients treated with nivolumab were noted to have an irAE. Patients with irAEs had a significantly longer median PFS [6.1 vs. 3.1 months, HR 0.68 95% CI (0.55-0.85); p = 0.001] and OS [14.9 vs. 7.4 months, HR 0.66 95% CI (0.52-0.82); p < 0.001)] compared to those without irAEs. In multivariate analysis, the presence of irAEs showed a significantly better PFS [HR 0.69, 95% CI (0.55-0.87); p = 0.002] and a trend for better OS [HR 0.62, 95% CI (0.55-1.03); p = 0.057]. Patients with permanent ICI discontinuation secondary to index irAE had a significantly shorter median PFS [2.3 vs. 6.6 months, HR 1.74 95% CI (1.06-2.80); p = 0.02] and median OS [3.6 vs. 17.6 months; HR 2.61 95% CI (1.61-4.21); p < 0.001] compared to those that did not have permanent ICI discontinuation. CONCLUSIONS: Our pooled exploratory analysis demonstrates improved clinical benefit to nivolumab in NSCLC patients experiencing irAEs. We also observed negative impact of irAE-related treatment discontinuation on survival in this group of patients.


Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/mortalidade , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/efeitos adversos , Idoso , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Metanálise como Assunto , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Suspensão de Tratamento
4.
BMC Cancer ; 20(1): 383, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32375706

RESUMO

BACKGROUND: The microbiome has been shown to affect the response to Immune Checkpoint Inhibitors (ICIs) in a small number of cancers and in preclinical models. Here, we sought to broadly survey cancers to identify those in which the microbiome may play a prognostic role using retrospective analyses of patients with advanced cancer treated with ICIs. METHODS: We conducted a retrospective analysis of 690 patients who received ICI therapy for advanced cancer. We used a literature review to define a causal model for the relationship between medications, the microbiome, and ICI response to guide the abstraction of electronic health records. Medications with precedent for changes to the microbiome included antibiotics, corticosteroids, proton pump inhibitors, histamine receptor blockers, non-steroid anti-inflammatories and statins. We tested the effect of medication timing on overall survival (OS) and evaluated the robustness of medication effects in each cancer. Finally, we compared the size of the effect observed for different classes of antibiotics to taxa that have been correlated to ICI response using a literature review of culture-based antibiotic susceptibilities. RESULTS: Of the medications assessed, only antibiotics and corticosteroids significantly associated with shorter OS. The hazard ratios (HRs) for antibiotics and corticosteroids were highest near the start of ICI treatment but remained significant when given prior to ICI. Antibiotics and corticosteroids remained significantly associated with OS even when controlling for multiple factors such as Eastern Cooperative Oncology Group performance status, Charlson Comorbidity Index score, and stage. When grouping antibiotics by class, ß-lactams showed the strongest association with OS across all tested cancers. CONCLUSIONS: The timing and strength of the correlations with antibiotics and corticosteroids after controlling for confounding factors are consistent with the microbiome involvement with the response to ICIs across several cancers.


Assuntos
Corticosteroides/efeitos adversos , Antibacterianos/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Bactérias/efeitos dos fármacos , Disbiose/mortalidade , Neoplasias/mortalidade , Disbiose/induzido quimicamente , Disbiose/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo
5.
Lancet Oncol ; 20(4): 581-590, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30827746

RESUMO

BACKGROUND: Cabozantinib is approved for patients with metastatic renal cell carcinoma on the basis of studies done in clear-cell histology. The activity of cabozantinib in patients with non-clear-cell renal cell carcinoma is poorly characterised. We sought to analyse the antitumour activity and toxicity of cabozantinib in advanced non-clear-cell renal cell carcinoma. METHODS: We did a multicentre, international, retrospective cohort study of patients with metastatic non-clear-cell renal cell carcinoma treated with oral cabozantinib during any treatment line at 22 centres: 21 in the USA and one in Belgium. Eligibility required patients with histologically confirmed non-clear-cell renal cell carcinoma who received cabozantinib for metastatic disease during any treatment line roughly between 2015 and 2018. Mixed tumours with a clear-cell histology component were excluded. No other restrictive inclusion criteria were applied. Data were obtained from retrospective chart review by investigators at each institution. Demographic, surgical, pathological, and systemic therapy data were captured with uniform database templates to ensure consistent data collection. The main objectives were to estimate the proportion of patients who achieved an objective response, time to treatment failure, and overall survival after treatment. FINDINGS: Of 112 identified patients with non-clear-cell renal cell carcinoma treated at the participating centres, 66 (59%) had papillary histology, 17 (15%) had Xp11.2 translocation histology, 15 (13%) had unclassified histology, ten (9%) had chromophobe histology, and four (4%) had collecting duct histology. The proportion of patients who achieved an objective response across all histologies was 30 (27%, 95% CI 19-36) of 112 patients. At a median follow-up of 11 months (IQR 6-18), median time to treatment failure was 6·7 months (95% CI 5·5-8·6), median progression-free survival was 7·0 months (5·7-9·0), and median overall survival was 12·0 months (9·2-17·0). The most common adverse events of any grade were fatigue (58 [52%]), and diarrhoea (38 [34%]). The most common grade 3 events were skin toxicity (rash and palmar-plantar erythrodysesthesia; five [4%]) and hypertension (four [4%]). No treatment-related deaths were observed. Across 54 patients with available next-generation sequencing data, the most frequently altered somatic genes were CDKN2A (12 [22%]) and MET (11 [20%]) with responses seen irrespective of mutational status. INTERPRETATION: While we await results from prospective studies, this real-world study provides evidence supporting the antitumour activity and safety of cabozantinib across non-clear-cell renal cell carcinomas. Continued support of international collaborations and prospective ongoing studies targeting non-clear-cell renal cell carcinoma subtypes and specific molecular alterations are warranted to improve outcomes across these rare diseases with few evidence-based treatment options. FUNDING: None.


Assuntos
Anilidas/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Idoso , Carcinoma de Células Renais/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Estudos Retrospectivos
6.
J Natl Compr Canc Netw ; 16(9): 1035-1040, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30181415

RESUMO

Mutations in the RAS/RAF/MEK/ERK pathway leading to constitutive activation and uncontrolled cellular growth have been identified in various human malignancies, making this pathway a target for potential therapeutics. The activating BRAFV600E mutation is one well-characterized oncogenic mutation that has been described and targeted with clinical success in various malignancies, including melanoma and hairy cell leukemia. Although BRAF-directed treatments have yielded clinical benefit in a subset of tumor types, such as melanoma, thyroid cancer, and lung cancer, BRAF inhibition fails to confer a clinical benefit in colon cancer. Identification of patients for whom BRAF inhibition may produce clinically meaningful outcomes is imperative. The incidence of BRAF mutations in neuroendocrine carcinoma (NEC) is estimated to be 5% to 10%. A recent case series demonstrated benefit in targeting the BRAFV600E mutation in metastatic high-grade rectal NECs. Combination BRAF and MEK inhibition is known to yield improved outcomes compared with BRAF inhibition alone in melanoma. This report presents 2 patients with high-grade colorectal NECs who had different responses to treatment with combined BRAF/MEK inhibition after experiencing disease progression through first-line platinum-based chemotherapy. One patient experienced an excellent initial response to therapy before ultimately experiencing progression, and in the other patient initially had stable disease before eventually experiencing progression. These cases highlight the complicated role BRAF mutations play in gastrointestinal NECs, and the need for further research to identify not only patients who may benefit from BRAF-directed therapies but also strategies to avoid development of resistance.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Neuroendócrino/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Biópsia , Carcinoma Neuroendócrino/diagnóstico por imagem , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/patologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , Feminino , Mutação com Ganho de Função , Humanos , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Indazóis , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Oximas/farmacologia , Oximas/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/farmacologia , Piridonas/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Pirimidinonas/farmacologia , Pirimidinonas/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Resultado do Tratamento
7.
Dev Biol ; 360(1): 44-57, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21945073

RESUMO

The dorsal habenular nuclei (Dh) of the zebrafish are characterized by significant left-right differences in gene expression, anatomy, and connectivity. Notably, the lateral subnucleus of the Dh (LsDh) is larger on the left side of the brain than on the right, while the medial subnucleus (MsDh) is larger on the right compared to the left. A screen for mutations that affect habenular laterality led to the identification of the sec61a-like 1(sec61al1) gene. In sec61al1(c163) mutants, more neurons in the LsDh and fewer in the MsDh develop on both sides of the brain. Generation of neurons in the LsDh occurs more rapidly and continues for a longer time period in mutants than in WT. Expression of Nodal pathway genes on the left side of the embryos is unaffected in mutants, as is the left sided placement of the parapineal organ, which promotes neurogenesis in the LsDh of WT embryos. Ultrastructural analysis of the epithalamus indicates that ventricular precursor cells, which form an epithelium in WT embryos, lose apical-basal polarity in sec61al1(c163) mutants. Our results show that in the absence of sec61al1, an excess of precursor cells for the LsDh exit the ventricular region and differentiate, resulting in formation of bilaterally symmetric habenular nuclei.


Assuntos
Habenula/embriologia , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/fisiologia , Peixe-Zebra/embriologia , Animais , Sequência de Bases , Padronização Corporal/genética , Padronização Corporal/fisiologia , Primers do DNA/genética , Retículo Endoplasmático/fisiologia , Habenula/citologia , Habenula/fisiologia , Modelos Neurológicos , Mutação , Neurogênese/genética , Neurogênese/fisiologia , Neurônios/citologia , Ligantes da Sinalização Nodal/genética , Ligantes da Sinalização Nodal/fisiologia , Fenótipo , Canais de Translocação SEC , Peixe-Zebra/genética , Peixe-Zebra/fisiologia
8.
Gastroenterology ; 139(3): 918-28, 928.e1-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20621629

RESUMO

BACKGROUND & AIMS: The atonal homolog 1 (Atoh1) transcription factor is required for intestinal secretory (goblet, Paneth, enteroendocrine) cell differentiation. Notch/gamma-secretase inhibitors (GSIs) block proliferation and induce secretory cell differentiation in the intestine. We used genetic analyses of mice to determine whether Atoh1 mediates the effects of GSIs in normal and cancerous intestinal epithelia. METHODS: We studied mice with intestine-specific disruption of Atoh1 (Atoh1(Deltaintestine)), the adenomatosis polyposis coli (APC)(min) mutation, both mutations (Atoh1(Deltaintestine); APC(min)), or littermate controls; mice were given GSI or vehicle. Colorectal cancer (CRC) cell lines were treated with GSI or vehicle and with small hairpin RNAs to reduce ATOH1. Differentiation and homeostasis were assessed by protein, RNA, and histologic analyses. RESULTS: GSIs failed to induce secretory cell differentiation or apoptosis or decrease proliferation of Atoh1-null progenitor cells, compared with wild-type cells. Exposure of APC(min) adenomas to GSIs decreased proliferation and increased secretory cell numbers in an Atoh1-dependent manner. In CRC cells treated with GSI, ATOH1 levels were correlated inversely with proliferation. ATOH1 was required for secretory cell gene expression in cell lines and in mice. CONCLUSIONS: ATOH1 is required for all effects of GSIs in intestinal crypts and adenomas; Notch has no unique function in intestinal progenitors and cancer cells other than to regulate ATOH1 expression. Reducing ATOH1 activity might mitigate intestinal toxicity from systemic GSI therapy for nonintestinal diseases. Among gastrointestinal malignancies, ATOH1 mediates the effects of GSIs, so ATOH1 expression levels might predict responses to these inhibitors. We propose that only the subset of CRCs that retain ATOH1 expression will respond to GSIs.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Antineoplásicos/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Células Epiteliais/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Receptores Notch/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Apoptose/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação Neoplásica da Expressão Gênica , Genes APC , Células HCT116 , Células HT29 , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Transgênicos , Interferência de RNA , RNA Mensageiro/metabolismo , Receptores Notch/metabolismo , Fatores de Tempo
9.
J Geriatr Oncol ; 12(5): 813-819, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33627226

RESUMO

OBJECTIVES: Despite growing evidence that checkpoint inhibitor immunotherapy (IO) toxicity is associated with improved treatment response, the relationship between immune-related adverse events (irAEs) and overall survival (OS) among older adults [age ≥ 70 years (y)] remains unknown. The study goal was to determine differences in OS based on age and ≥ grade 3 (G3) irAEs. MATERIALS AND METHODS: This was a retrospective cohort study of 673 patients with advanced cancer. Patients who received ≥1 dose of IO at our institution from 2011 to 2018 were eligible. The primary outcome was OS from the start of first line of IO treatment, compared between four patient groups stratified by age and ≥ G3 irAEs with adjustment for patient characteristics using a Cox proportional hazards model. RESULTS AND CONCLUSION: Among all 673 patients, 35.4% were ≥ 70y, 39.8% had melanoma, and 45.6% received single-agent nivolumab. Incidence and types of ≥G3 irAEs did not differ by age. Median OS was significantly longer for all patients with ≥G3 irAEs (unadjusted 21.7 vs. 11.9 months, P = 0.007). There was no difference in OS among patients ≥70y with ≥G3 irAEs (HR 0.94, 95% CI 0.61-1.47, P = 0.79) in the multivariable analysis. Patients <70y with ≥G3 irAEs had significantly increased OS (HR 0.33, 95% CI 0.21-0.52, P < 0.001). Younger patients, but not older adults, with high-grade irAEs experience strong survival benefit. This difference may be due to the toll of irAEs themselves or the effects of treatments for irAEs, such as corticosteroids. Factors impacting OS of older adults after irAEs must be determined and optimized.


Assuntos
Imunoterapia , Melanoma , Idoso , Humanos , Fatores Imunológicos , Imunoterapia/efeitos adversos , Melanoma/tratamento farmacológico , Nivolumabe/efeitos adversos , Estudos Retrospectivos
10.
J Cancer Res Clin Oncol ; 145(10): 2541-2546, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31367835

RESUMO

BACKGROUND: The neutrophil to lymphocyte ratio (NLR) is known to be prognostic for patients with advanced cancers treated with immune checkpoint inhibitors (ICI), but has generally been evaluated as a single threshold value at baseline. We evaluated NLR at baseline and within first month during treatment in patients who received ICI for advanced cancer to evaluate the prognostic value of baseline and of changes from baseline to on-treatment NLR. METHODS: A retrospective review of patients with advanced cancer treated with ICI from 2011 to 2017 at the Ohio State University was performed. NLR was calculated at the initiation of ICI and repeated at median of 21 days. Overall survival (OS) was calculated from the initiation of ICI to date of death or censored at last follow-up. Significance of Cox proportional hazards models were evaluated by log-rank test. Calculations were performed using the survival and survminer packages in R, and SPSS. RESULTS: 509 patients were identified and included in the analysis. Patients with baseline and on-treatment NLR < 5 had significantly longer OS (P < 0.001). The change in NLR overtime was a predictor of OS and was observed to be non-linear in nature. This property remained statistically significant with P < 0.05 after adjusting for age, body mass index, sex, cancer type, performance status, and days to repeat NLR measurement. Patients with a moderate decrease in NLR from baseline had the longest OS of 27.8 months (95% CI 21.8-33.8). Patients with significant NLR decrease had OS of 11.4 months (95% CI 6.1-16.7). Patients with a significant increase in NLR had the shortest OS of 5.0 months (95% CI 0.9-9.1). CONCLUSIONS: We confirmed the prognostic value of NLR in patients with advanced cancer treated with ICIs. We found that change in NLR over time is a non-linear predictor of patient outcomes. Patients who had moderate decrease in NLR during treatment with ICI were found to have the longest survival, whereas a significant decrease or increase in NLR was associated with shorter survival. To our knowledge, this is the first study to demonstrate a non-linear change in NLR over time that correlates with survival.


Assuntos
Contagem de Leucócitos , Contagem de Linfócitos , Linfócitos , Neoplasias/sangue , Neoplasias/mortalidade , Neutrófilos , Adulto , Idoso , Biomarcadores , Feminino , Humanos , Imunoterapia , Estimativa de Kaplan-Meier , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias/imunologia , Neoplasias/terapia , Neutrófilos/imunologia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
11.
Case Rep Pulmonol ; 2015: 283875, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26366316

RESUMO

The case reported is a young "light" ex-smoker who initially had a localized adenosquamous carcinoma bearing an epidermal growth factor receptor (EGFR) sensitizing mutation. He first recurred six months after initial treatment within the brain with a pure squamous histology and the same EGFR mutation. Surgical resection and radiation rendered him disease-free. Subsequent isolated recurrence within the lung eighteen months later was a pure adenocarcinoma, again with the same identified EGFR mutation. These histologic changes (from adenosquamous to pure squamous to pure adenocarcinoma) have been described but not before in the absence of any selection pressure with EGFR tyrosine kinase inhibitors. This case points out the histologic "flexibility" of EGFR mutant lung cancers and the importance for appropriate molecular testing in nonsmokers with lung cancer of any histologic type.

13.
Dev Dyn ; 237(12): 3538-44, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18629869

RESUMO

The pineal complex of zebrafish consists of a pineal organ and a left-sided parapineal organ. Mutation of the floating head (flh) gene, which encodes a homeodomain protein, causes premature termination of pineal cell division without affecting specification or asymmetric placement of the parapineal. The from beyond (fby) mutation, a premature stop codon in the T-domain-containing protein Tbx2b, disrupts formation of the parapineal while leaving the pineal largely intact. However, flh is reported as being required for tbx2b transcription. To resolve the paradox that flhand tbx2b mutants have opposite phenotypes but have been placed in the same genetic pathway, we have examined transcriptional cross-regulation in single flh or fby mutants and genetic epistasis in double mutants. Careful analysis shows that flh is not required for tbx2b transcription and double mutants exhibit an additive phenotype. We conclude that Flh and Tbx2b regulate separate programs of pineal and parapineal development.


Assuntos
Padronização Corporal , Proteínas de Homeodomínio/metabolismo , Glândula Pineal/embriologia , Glândula Pineal/metabolismo , Proteínas com Domínio T/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Animais , Divisão Celular , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Mutação/genética , Fenótipo , Glândula Pineal/citologia , Proteínas com Domínio T/genética , Fatores de Transcrição/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
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