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1.
BMC Med ; 21(1): 255, 2023 07 14.
Article in English | MEDLINE | ID: mdl-37452374

ABSTRACT

BACKGROUND: The feasibility of DNA methylation-based assays in detecting minimal residual disease (MRD) and postoperative monitoring remains unestablished. We aim to investigate the dynamic characteristics of cancer-related methylation signals and the feasibility of methylation-based MRD detection in surgical lung cancer patients. METHODS: Matched tumor, tumor-adjacent tissues, and longitudinal blood samples from a cohort (MEDAL) were analyzed by ultra-deep targeted sequencing and bisulfite sequencing. A tumor-informed methylation-based MRD (timMRD) was employed to evaluate the methylation status of each blood sample. Survival analysis was performed in the MEDAL cohort (n = 195) and validated in an independent cohort (DYNAMIC, n = 36). RESULTS: Tumor-informed methylation status enabled an accurate recurrence risk assessment better than the tumor-naïve methylation approach. Baseline timMRD-scores were positively correlated with tumor burden, invasiveness, and the existence and abundance of somatic mutations. Patients with higher timMRD-scores at postoperative time-points demonstrated significantly shorter disease-free survival in the MEDAL cohort (HR: 3.08, 95% CI: 1.48-6.42; P = 0.002) and the independent DYNAMIC cohort (HR: 2.80, 95% CI: 0.96-8.20; P = 0.041). Multivariable regression analysis identified postoperative timMRD-score as an independent prognostic factor for lung cancer. Compared to tumor-informed somatic mutation status, timMRD-scores yielded better performance in identifying the relapsed patients during postoperative follow-up, including subgroups with lower tumor burden like stage I, and was more accurate among relapsed patients with baseline ctDNA-negative status. Comparing to the average lead time of ctDNA mutation, timMRD-score yielded a negative predictive value of 97.2% at 120 days prior to relapse. CONCLUSIONS: The dynamic methylation-based analysis of peripheral blood provides a promising strategy for postoperative cancer surveillance. TRIAL REGISTRATION: This study (MEDAL, MEthylation based Dynamic Analysis for Lung cancer) was registered on ClinicalTrials.gov on 08/05/2018 (NCT03634826). https://clinicaltrials.gov/ct2/show/NCT03634826 .


Subject(s)
Cell-Free Nucleic Acids , Circulating Tumor DNA , Lung Neoplasms , Humans , Cell-Free Nucleic Acids/genetics , Circulating Tumor DNA/genetics , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , Lung Neoplasms/surgery , DNA Methylation/genetics , Biomarkers, Tumor/genetics
2.
Gynecol Oncol ; 167(2): 295-305, 2022 11.
Article in English | MEDLINE | ID: mdl-36096974

ABSTRACT

OBJECTIVES: Ovarian cancer is a fatal gynecological cancer due to the lack of effective screening strategies at early stage. This study explored the utility of DNA methylation profiling of blood samples for the detection of ovarian cancer. METHODS: Targeted bisulfite sequencing was performed on tissue (n = 152) and blood samples (n = 373) obtained from healthy women, women with benign ovarian tumors, or malignant epithelial ovarian tumors. Based on the tissue-derived differentially-methylated regions, a supervised machine learning algorithm was implemented and cross-validated using the blood-derived DNA methylation profiles of the training cohort (n = 178) to predict and classify each blood sample as malignant or non-malignant. The model was further evaluated using an independent test cohort (n = 184). RESULTS: Comparison of the DNA methylation profiles of normal/benign and malignant tumor samples identified 1272 differentially-methylated regions, with 49.4% hypermethylated regions and 50.6% hypomethylated regions. Five-fold cross-validation of the model using the training dataset yielded an area under the curve of 0.94. Using the test dataset, the model accurately predicted non-malignancy in 96.2% of healthy women (n = 53) and 93.5% of women with benign tumors (n = 46). For patients with malignant tumors, the model accurately predicted malignancy in 44.4% of stage I-II (n = 9), 86.4% of stage III (n = 59), 100.0% of stage IV tumors (n = 6), and 81.8% of tumors with unknown stage (n = 11). Overall, the model yielded a predictive accuracy of 89.5%. CONCLUSIONS: Our study demonstrates the potential clinical application of blood-based DNA methylation profiling for the detection of ovarian cancer.


Subject(s)
DNA Methylation , Ovarian Neoplasms , Humans , Female , Ovarian Neoplasms/diagnosis , Ovarian Neoplasms/genetics , Biomarkers, Tumor/genetics
3.
BMC Med ; 20(1): 64, 2022 02 07.
Article in English | MEDLINE | ID: mdl-35130881

ABSTRACT

BACKGROUND: DNA methylation-associated studies on biliary tract cancer (BTC), including cholangiocarcinoma (CCA) and gallbladder cancer (GBC), may improve the BTC classification scheme. We proposed to identify the shared methylation changes of BTCs and investigate their associations with genomic aberrations, immune characteristics, and survival outcomes. METHODS: Multi-dimensional data concerning mutation, DNA methylation, immune-related features, and clinical data of 57 CCAs and 48 GBCs from Eastern Hepatobiliary Surgery Hospital (EHSH) and 36 CCAs in the TCGA-CHOL cohort were analyzed. RESULTS: In our cohort including 24 intrahepatic CCAs (iCCAs), 20 perihilar CCAs (pCCAs), 13 distal CCAs (dCCAs), and 48 GBCs, 3369 common differentially methylated regions (DMRs) were identified by comparing tumor and non-tumor samples. A lower level of methylation changes of these common DMRs was associated with fewer copy number variations, fewer mutational burden, and remarkably longer overall survival (OS, hazard ratio [HR] = 0.07, 95% confidence interval [CI] 0.01-0.65, P = 0.017). Additionally, a 12-marker model was developed and validated for prognostication after curative surgery (HR = 0.21, 95% CI 0.10-0.43, P < 0.001), which exhibited undifferentiated prognostic effects in subgroups defined by anatomic location (iCCAs, d/pCCAs, GBCs), TNM stage, and tumor purity. Its prognostic utility remained significant in multivariable analysis (HR = 0.26, 95% CI 0.11-0.59, P = 0.001). Moreover, the BTCs with minimal methylation changes exhibited higher immune-related signatures, infiltration of CD8+ lymphocytes, and programmed death-ligand 1 (PD-L1) expression, indicating an inflamed tumor immune microenvironment (TIME) with PD-L1 expression elicited by immune attack, potentially suggesting better immunotherapy efficacy. CONCLUSIONS: In BTCs, DNA methylation is a powerful tool for molecular classification, serving as a robust indicator of genomic aberrations, survival outcomes, and tumor immune microenvironment. Our integrative analysis provides insights into the prognostication after curative surgery and patient selection for immunotherapy.


Subject(s)
Bile Duct Neoplasms , Biliary Tract Neoplasms , Bile Duct Neoplasms/drug therapy , Bile Duct Neoplasms/genetics , Bile Duct Neoplasms/pathology , Bile Ducts, Intrahepatic/pathology , Biliary Tract Neoplasms/drug therapy , Biliary Tract Neoplasms/genetics , Biliary Tract Neoplasms/pathology , DNA Copy Number Variations , DNA Methylation/genetics , Humans , Tumor Microenvironment
4.
Ann Med ; 54(1): 369-378, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35107389

ABSTRACT

OBJECTIVES: To evaluate the effectiveness of repetitive thoracic paravertebral block (TPVB) under ultrasound (US) guidance for acute pain associated to herpes zoster (HZ) and its prophylactic effects on post-herpetic neuralgia (PHN). METHODS: Patients who suffered from acute pain associated to HZ within 1 week of rash onset were randomized in a ratio of 1:1 to receive a seven-day course antiviral therapy, antiviral therapy with additional US-guided repetitive TPVB using transverse short axial (TSA) approach every 48 h for a week after antiviral therapy. All patients were allowed to receive rescue analgesics. The primary endpoint was HZ burden of illness (HZ-BOI) measured by a severity-by-duration composite pain assessment conducted 1-month post inclusion. Adverse events were also recorded. RESULTS: A total of 96 patients completed the entire 6-month follow-up. The BOI-30AUC was 112.5 (95%CI: 105.2, 119.9) in control group, and 82.7 (95%CI: 75.4, 90.1) in TPVB group (F = 32.252, p<.001) at D30 after inclusion. Compared with control group, significant reductions of BOI-30-90AUC, and BOI-90-180AUC were observed in TPVB group (F = 11.392, p=.001 at D90; F = 7.467, p=.007 at D180, respectively). At 3 and 6 months after inclusion, the incidence of PHN in TPVB group was significantly lower than control group. Quality of life (QoL) in TPVB group also showed greater improvements at all the time points in all domains of EQ-5D-3L (p<.05). No serious adverse events were observed. CONCLUSIONS: US-guided repetitive TPVB significantly reduced the HZ-BOI and the PHN incidence compared to antiviral therapy alone. It might be considered as an early intervention and preventive strategy to the development of PHN after acute HZ.KEY MESSAGEThis is a prospective randomized comparative study. We made a hypothesis that US-guided repetitive thoracic paravertebral block (TPVB) using a transverse short axial (TSA) approach to treat thoracic herpes zoster (HZ) in acute phase could reduce the burden of illness associated to acute pain. Moreover, this therapy might be a feasible preventive strategy to reduce the incidence of post-herpetic neuralgia.


Subject(s)
Herpes Zoster , Quality of Life , Antiviral Agents/therapeutic use , Humans , Prospective Studies , Ultrasonography, Interventional
5.
BMC Med ; 20(1): 8, 2022 01 14.
Article in English | MEDLINE | ID: mdl-35027051

ABSTRACT

BACKGROUND: Aberrant DNA methylation may offer opportunities in revolutionizing cancer screening and diagnosis. We sought to identify a non-invasive DNA methylation-based screening approach using cell-free DNA (cfDNA) for early detection of hepatocellular carcinoma (HCC). METHODS: Differentially, DNA methylation blocks were determined by comparing methylation profiles of biopsy-proven HCC, liver cirrhosis, and normal tissue samples with high throughput DNA bisulfite sequencing. A multi-layer HCC screening model was subsequently constructed based on tissue-derived differentially methylated blocks (DMBs). This model was tested in a cohort consisting of 120 HCC, 92 liver cirrhotic, and 290 healthy plasma samples including 65 hepatitis B surface antigen-seropositive (HBsAg+) samples, independently validated in a cohort consisting of 67 HCC, 111 liver cirrhotic, and 242 healthy plasma samples including 56 HBsAg+ samples. RESULTS: Based on methylation profiling of tissue samples, 2321 DMBs were identified, which were subsequently used to construct a cfDNA-based HCC screening model, achieved a sensitivity of 86% and specificity of 98% in the training cohort and a sensitivity of 84% and specificity of 96% in the independent validation cohort. This model obtained a sensitivity of 76% in 37 early-stage HCC (Barcelona clinical liver cancer [BCLC] stage 0-A) patients. The screening model can effectively discriminate HCC patients from non-HCC controls, including liver cirrhotic patients, asymptomatic HBsAg+ and healthy individuals, achieving an AUC of 0.957(95% CI 0.939-0.975), whereas serum α-fetoprotein (AFP) only achieved an AUC of 0.803 (95% CI 0.758-0.847). Besides detecting patients with early-stage HCC from non-HCC controls, this model showed high capacity for distinguishing early-stage HCC from a high risk population (AUC=0.934; 95% CI 0.905-0.963), also significantly outperforming AFP. Furthermore, our model also showed superior performance in distinguishing HCC with normal AFP (< 20ng ml-1) from high risk population (AUC=0.93; 95% CI 0.892-0.969). CONCLUSIONS: We have developed a sensitive blood-based non-invasive HCC screening model which can effectively distinguish early-stage HCC patients from high risk population and demonstrated its performance through an independent validation cohort. TRIAL REGISTRATION: The study was approved by the ethic committee of The Second Xiangya Hospital of Central South University (KYLL2018072) and Chongqing University Cancer Hospital (2019167). The study is registered at ClinicalTrials.gov(# NCT04383353 ).


Subject(s)
Carcinoma, Hepatocellular , Cell-Free Nucleic Acids , Liver Neoplasms , Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/genetics , Cell-Free Nucleic Acids/genetics , DNA Methylation , Diagnosis, Differential , Humans , Liver Cirrhosis/diagnosis , Liver Cirrhosis/genetics , Liver Neoplasms/diagnosis , Liver Neoplasms/genetics
6.
BMC Med ; 19(1): 243, 2021 10 13.
Article in English | MEDLINE | ID: mdl-34641873

ABSTRACT

BACKGROUND: Plasma cell-free DNA (cfDNA) methylation has shown promising results in the early detection of multiple cancers recently. Here, we conducted a study to investigate the performance of cfDNA methylation in the early detection of esophageal cancer (ESCA). METHODS: Specific methylation markers for ESCA were identified and optimized based on esophageal tumor and paired adjacent tissues (n = 24). Age-matched participants with ESCA (n = 85), benign esophageal diseases (n = 10), and healthy controls (n = 125) were randomized into the training and test sets to develop a classifier to differentiate ESCA from healthy controls and benign esophageal disease. The classifier was further validated in an independent plasma cohort of ESCA patients (n = 83) and healthy controls (n = 98). RESULTS: In total, 921 differentially methylated regions (DMRs) between tumor and adjacent tissues were identified. The early detection classifier based on those DMRs was first developed and tested in plasma samples, discriminating ESCA patients from benign and healthy controls with a sensitivity of 76.2% (60.5-87.9%) and a specificity of 94.1% (85.7-98.4%) in the test set. The performance of the classifier was consistent irrespective of sex, age, and pathological diagnosis (P > 0.05). In the independent plasma validation cohort, similar performance was observed with a sensitivity of 74.7% (64.0-83.6%) and a specificity of 95.9% (89.9-98.9%). Sensitivity for stage 0-II was 58.8% (44.2-72.4%). CONCLUSION: We demonstrated that the cfDNA methylation patterns could distinguish ESCAs from healthy individuals and benign esophageal diseases with promising sensitivity and specificity. Further prospective evaluation of the classifier in the early detection of ESCAs in high-risk individuals is warranted.


Subject(s)
Cell-Free Nucleic Acids , Esophageal Neoplasms , Biomarkers, Tumor/genetics , Case-Control Studies , DNA Methylation , Early Detection of Cancer , Esophageal Neoplasms/diagnosis , Esophageal Neoplasms/genetics , Humans
8.
Ann Transl Med ; 9(13): 1080, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34422992

ABSTRACT

BACKGROUND: Differentiating malignant lung tumors from benign pulmonary nodules is a great challenge. While the analysis of bronchoalveolar lavage fluid (BALF) is used for diagnosing infections and interstitial lung diseases, there is limited evidence to support its use for lung cancer diagnosis. This study aimed to interrogate the potential of using BALF cell-free DNA (cfDNA) to discriminate malignant lesions from benign nodules. METHODS: Fifty-three patients with solid pulmonary nodules (≤2 cm) were prospectively enrolled, including 21 confirmed with benign disease and 32 with malignant tumors. Mutations were profiled for 30 tumor tissues and 40 BALFs. Paired BALFs and plasma from 48 patients underwent DNA methylation profiling. A methylome-based classification model was developed for BALF and plasma separately. RESULTS: Among the 30 patients with paired tissues and BALFs, 96.7% and 70% had alterations detected from their tissues (79 alterations) and BALFs (53 alterations), respectively. Using tissues as references, BALFs revealed 14 new alterations and missed 41. BALF mutation displayed a sensitivity of 71%, specificity of 77.8%, and accuracy of 72.5% in detecting lung cancer. BALF methylation achieved an accuracy of 81.3%, with both sensitivity and specificity being 81%. Plasma methylation showed a 66.7% sensitivity, 71.4% specificity, and 68.8% accuracy. BALF methylation also demonstrated 82.4% sensitivity in stage I patients. Parallel bronchoscopy, lavage cytology, and bronchial brushing demonstrated an inferior sensitivity of 23%, 3.1%, and 9.7%, respectively, compared with BALF methylation and mutation (P<0.0001). CONCLUSIONS: BALF cfDNA can serve as a liquid biopsy media for both mutation and methylation profiling, demonstrating better sensitivities in distinguishing small malignant tumors from benign nodules than conventional methods. KEYWORDS: Lung cancer diagnosis; pulmonary nodule; bronchoalveolar lavage fluid (BALF); methylation; genomic mutation.

9.
Nat Biomed Eng ; 5(6): 586-599, 2021 06.
Article in English | MEDLINE | ID: mdl-34131323

ABSTRACT

The low abundance of circulating tumour DNA (ctDNA) in plasma samples makes the analysis of ctDNA biomarkers for the detection or monitoring of early-stage cancers challenging. Here we show that deep methylation sequencing aided by a machine-learning classifier of methylation patterns enables the detection of tumour-derived signals at dilution factors as low as 1 in 10,000. For a total of 308 patients with surgery-resectable lung cancer and 261 age- and sex-matched non-cancer control individuals recruited from two hospitals, the assay detected 52-81% of the patients at disease stages IA to III with a specificity of 96% (95% confidence interval (CI) 93-98%). In a subgroup of 115 individuals, the assay identified, at 100% specificity (95% CI 91-100%), nearly twice as many patients with cancer as those identified by ultradeep mutation sequencing analysis. The low amounts of ctDNA permitted by machine-learning-aided deep methylation sequencing could provide advantages in cancer screening and the assessment of treatment efficacy.


Subject(s)
Biomarkers, Tumor/genetics , Circulating Tumor DNA/genetics , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , Machine Learning/statistics & numerical data , Adult , Biomarkers, Tumor/blood , Case-Control Studies , Circulating Tumor DNA/blood , DNA Methylation , Early Detection of Cancer/methods , Female , High-Throughput Nucleotide Sequencing , Humans , Lung Neoplasms/blood , Lung Neoplasms/pathology , Male , Middle Aged , Sequence Analysis, DNA/methods
10.
Clin Epigenetics ; 13(1): 26, 2021 02 03.
Article in English | MEDLINE | ID: mdl-33536049

ABSTRACT

BACKGROUND: Early detection of colorectal carcinoma (CRC) would help to identify tumors when curative treatments are available and beneficial. However, current screening methods for CRC, e.g., colonoscopy, may affect patients' compliance due to the uncomfortable, invasive and time-consuming process. In recent decades, methylation profiles of blood-based circulating tumor DNA (ctDNA) have shown promising results in the early detection of multiple tumors. Here we conducted a study to investigate the performance of ctDNA methylation markers in early detection of CRC. RESULTS: In total, 742 participants were enrolled in the study including CRC (n = 332), healthy control (n = 333), benign colorectal disease (n = 65) and advanced adenoma (n = 12). After age-matched and randomization, 298 participants (149 cancer and 149 healthy control) were included in training set and 141 (67 cancer and 74 healthy control) were in test set. In the training set, the specificity was 89.3% (83.2-93.7%) and the sensitivity was 88.6% (82.4-93.2%). In terms of different stages, the sensitivities were 79.4% (62.1-91.2%) in patients with stage I, 88.9% (77.3-95.8%) in patients with stage II, 91.4% (76.9-98.2%) in patients with stage III and 96.2% (80.3-99.9%) in patients with stage IV. Similar results were validated in the test set with the specificity of 91.9% (83.1-97.0%) and sensitivity of 83.6% (72.5-91.6%). Sensitivities for stage I-III were 87.0% (79.7-92.4%) in the training set and 82.5% (70.2-91.3%) in the test set, respectively. In the unmatched total population, the positive ratios were 7.8% (5.2-11.2%) in healthy control, 30.8% (19.9-43.5%) in benign colorectal disease and 58.3% (27.5-84.7%) in advanced adenoma, while the sensitivities of stage I-IV were similar with training and test sets. Compared with methylated SEPT9 model, the present model had higher sensitivity (87.0% [81.8-91.2%] versus 41.2% [34.6-48.1%], P < 0.001) under comparable specificity (90.1% [85.4-93.7%] versus 90.6% [86.0-94.1%]). CONCLUSIONS: Together our findings showed that ctDNA methylation markers were promising in the early detection of CRC. Further validation of this model is warranted in prospective studies.


Subject(s)
Adenoma/genetics , Circulating Tumor DNA/genetics , Colorectal Neoplasms/genetics , Early Detection of Cancer/methods , Adenoma/blood , Adenoma/diagnosis , Adenoma/pathology , Aged , Biomarkers, Tumor/genetics , Case-Control Studies , Circulating Tumor DNA/blood , Colorectal Neoplasms/blood , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/pathology , DNA Methylation , Epigenesis, Genetic , Female , Humans , Male , Middle Aged , Neoplasm Staging/methods , Prospective Studies , Sensitivity and Specificity
11.
BMC Cancer ; 19(1): 579, 2019 Jun 13.
Article in English | MEDLINE | ID: mdl-31195991

ABSTRACT

BACKGROUND: Detection of circulating tumor DNA (ctDNA) is a promising method for postoperative surveillance of lung cancer. However, relatively low positive rate in early stage patients restricts its application. Aberrant methylation of ctDNA can be detected in blood samples, and may provide a more sensitive method. This study is designed to systematically evaluate and compare the detection of aberrant methylation and mutations in ctDNA among surgical non-small cell lung cancer (NSCLC) patients, aiming to investigate the feasibility of ctDNA detection as a means of lung cancer surveillance. METHODS: This is a prospective observational study. Consecutive surgical NSCLC patients will be recruited. Blood samples will be collected both before and after surgery (during the follow-up period), while matching tumor tissues and tumor-adjacent normal tissues will be collected during surgery. Quantitative analysis of aberrant methylation and mutations of ctDNA will be conducted in combination with a three-year follow-up data. DISCUSSION: This is the first registered prospective study designed to investigate the feasibility of ctDNA methylation detection as a means of postoperative lung cancer surveillance. We will systematically evaluate and compare the quantitative detection of ctDNA mutations and ctDNA methylation in surgical NSCLC patients, combining with the follow-up information. By integrating genetic and epigenetic information of ctDNA, more effective strategies for postoperative surveillance may be defined. TRIAL REGISTRATION: This study (MEDAL, MEthylation based Dynamic Analysis for Lung cancer) was registered on ClinicalTrials.gov on 08/05/2018 (NCT03634826; Pre-results).


Subject(s)
Circulating Tumor DNA/blood , Lung Neoplasms/diagnosis , Pneumonectomy , Biomarkers, Tumor/genetics , DNA Methylation , Female , Follow-Up Studies , Humans , Lung Neoplasms/surgery , Male , Monitoring, Immunologic , Monitoring, Physiologic , Mutation/genetics , Neoplasm Staging , Postoperative Period , Prospective Studies
12.
Development ; 145(5)2018 03 01.
Article in English | MEDLINE | ID: mdl-29437830

ABSTRACT

Human cleft lip with or without cleft palate (CL/P) is a common craniofacial abnormality caused by impaired fusion of the facial prominences. We have previously reported that, in the mouse embryo, epithelial apoptosis mediates fusion at the seam where the prominences coalesce. Here, we show that apoptosis alone is not sufficient to remove the epithelial layers. We observed morphological changes in the seam epithelia, intermingling of cells of epithelial descent into the mesenchyme and molecular signatures of epithelial-mesenchymal transition (EMT). Utilizing mouse lines with cephalic epithelium-specific Pbx loss exhibiting CL/P, we demonstrate that these cellular behaviors are Pbx dependent, as is the transcriptional regulation of the EMT driver Snail1. Furthermore, in the embryo, the majority of epithelial cells expressing high levels of Snail1 do not undergo apoptosis. Pbx1 loss- and gain-of-function in a tractable epithelial culture system revealed that Pbx1 is both necessary and sufficient for EMT induction. This study establishes that Pbx-dependent EMT programs mediate murine upper lip/primary palate morphogenesis and fusion via regulation of Snail1. Of note, the EMT signatures observed in the embryo are mirrored in the epithelial culture system.


Subject(s)
Body Patterning/genetics , Epithelial-Mesenchymal Transition/genetics , Face/embryology , Morphogenesis/genetics , Nose/embryology , Pre-B-Cell Leukemia Transcription Factor 1/physiology , Snail Family Transcription Factors/genetics , Animals , Apoptosis/genetics , Cells, Cultured , Cleft Lip/embryology , Cleft Lip/genetics , Cleft Palate/embryology , Cleft Palate/genetics , Embryo, Mammalian , Face/abnormalities , Gene Expression Regulation, Developmental , Lip/embryology , Mice , Mice, Transgenic , Palate/embryology , Pre-B-Cell Leukemia Transcription Factor 1/genetics
13.
EMBO J ; 35(18): 1963-78, 2016 09 15.
Article in English | MEDLINE | ID: mdl-27354364

ABSTRACT

Pre-B-cell leukemia homeobox (PBX) transcription factors are known to regulate organogenesis, but their molecular targets and function in midbrain dopaminergic neurons (mDAn) as well as their role in neurodegenerative diseases are unknown. Here, we show that PBX1 controls a novel transcriptional network required for mDAn specification and survival, which is sufficient to generate mDAn from human stem cells. Mechanistically, PBX1 plays a dual role in transcription by directly repressing or activating genes, such as Onecut2 to inhibit lateral fates during embryogenesis, Pitx3 to promote mDAn development, and Nfe2l1 to protect from oxidative stress. Notably, PBX1 and NFE2L1 levels are severely reduced in dopaminergic neurons of the substantia nigra of Parkinson's disease (PD) patients and decreased NFE2L1 levels increases damage by oxidative stress in human midbrain cells. Thus, our results reveal novel roles for PBX1 and its transcriptional network in mDAn development and PD, opening the door for new therapeutic interventions.


Subject(s)
Cell Differentiation , DNA-Binding Proteins/metabolism , Dopaminergic Neurons/physiology , Gene Regulatory Networks , Parkinson Disease/pathology , Proto-Oncogene Proteins/metabolism , Substantia Nigra/pathology , Humans , Pre-B-Cell Leukemia Transcription Factor 1
14.
Dev Cell ; 21(4): 627-41, 2011 Oct 18.
Article in English | MEDLINE | ID: mdl-21982646

ABSTRACT

Morphogenesis of mammalian facial processes requires coordination of cellular proliferation, migration, and apoptosis to develop intricate features. Cleft lip and/or palate (CL/P), the most frequent human craniofacial birth defect, can be caused by perturbation of any of these programs. Mutations of WNT, P63, and IRF6 yield CL/P in humans and mice; however, how these genes are regulated remains elusive. We generated mouse lines lacking Pbx genes in cephalic ectoderm and demonstrated that they exhibit fully penetrant CL/P and perturbed Wnt signaling. We also characterized a midfacial regulatory element that Pbx proteins bind to control the expression of Wnt9b-Wnt3, which in turn regulates p63. Altogether, we establish a Pbx-dependent Wnt-p63-Irf6 regulatory module in midfacial ectoderm that is conserved within mammals. Dysregulation of this network leads to localized suppression of midfacial apoptosis and CL/P. Ectopic Wnt ectodermal expression in Pbx mutants rescues the clefting, opening avenues for tissue repair.


Subject(s)
Apoptosis , Epithelial Cells/metabolism , Face/embryology , Homeodomain Proteins/physiology , Interferon Regulatory Factors/metabolism , Phosphoproteins/metabolism , Trans-Activators/metabolism , Transcription Factors/physiology , Wnt Proteins/metabolism , Wnt3 Protein/metabolism , Animals , Base Sequence , Blotting, Western , Cell Proliferation , Chromatin Immunoprecipitation , Cleft Lip/embryology , Cleft Lip/metabolism , Cleft Palate/embryology , Cleft Palate/metabolism , Electrophoretic Mobility Shift Assay , Humans , Immunoenzyme Techniques , Interferon Regulatory Factors/genetics , Luciferases/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Molecular Sequence Data , Morphogenesis/physiology , Phenotype , Phosphoproteins/genetics , Pre-B-Cell Leukemia Transcription Factor 1 , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Nucleic Acid , Trans-Activators/genetics , Transfection , Wnt Proteins/genetics , Wnt3 Protein/genetics
15.
Dev Biol ; 344(2): 745-57, 2010 Aug 15.
Article in English | MEDLINE | ID: mdl-20678977

ABSTRACT

Polarity is a fundamental cellular feature that is critical for generating cell diversity and maintaining organ functions during development. In C. elegans, the one-cell embryo is polarized via asymmetric localization of the PAR proteins, which in turn are required to establish the future anterior-posterior axis of the embryo. PAR-3, a conserved PDZ domain-containing protein, acts with PAR-6 and PKC-3 (atypical protein kinase; aPKC) to regulate cell polarity and junction formation in a variety of cell types. To understand how PAR-3 localizes and functions during C. elegans development, we produced targeted mutations and deletions of conserved domains of PAR-3 and examined the localization and function of the GFP-tagged proteins in C. elegans embryos and larvae. We find that CR1, the PAR-3 self-oligomerization domain, is required for PAR-3 cortical distribution and function only during early embryogenesis and that PDZ2 is required for PAR-3 to accumulate stably at the cell periphery in early embryos and at the apical surface in pharyngeal and intestinal epithelial cells. We also show that phosphorylation at S863 by PKC-3 is not essential in early embryogenesis, but is important in later development. Surprisingly neither PDZ1 nor PDZ3 are essential for localization or function. Our results indicate that the different domains and phosphorylated forms of PAR-3 can have different roles during C. elegans development.


Subject(s)
Caenorhabditis elegans/metabolism , Cell Polarity/physiology , Protein Kinase C/metabolism , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans/physiology , Cell Polarity/genetics , Epithelial Cells/cytology , Epithelial Cells/metabolism , Epithelial Cells/physiology , Membrane Proteins , Neoplasm Proteins , PDZ Domains , Poly(ADP-ribose) Polymerases/genetics , Poly(ADP-ribose) Polymerases/metabolism , Protein Kinase C/genetics , Protein Kinase C/physiology , Proteins/genetics , Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
16.
Hybrid Hybridomics ; 21(4): 295-300, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12193283

ABSTRACT

To develop monoclonal antibodies (MAbs) to neutralize human telomerase, an epitope (hTERT(7)) in reverse transcriptase domain of hTERT was synthesized and was used to immunize BALB/c mice. Hybridomas were generated and screened by enzyme-linked immunoadsorbent assay (ELISA) for specific MAbs. One hybridoma M2 clone, isotyped IgG(1), was established. The competitive assay confirmed that the M2 antibody was hTERT(7) specific, and the affinity constant was about 1 x 10(6) M(-1). M2 could recognize cell extracts from HeLa cancer cells but not those of normal 2BS cells in ELISA assay. For in situ staining immunohistochemically, the positive staining presented in the nuclear compartment of HeLa, while 2BS was nonreactive. In TRAP-PCR ELISA, M2 markedly decreased the activities of human telomerase in HeLa cells. The sequencing of M2 heavy chain variable region proved its mouse origin. The results demonstrated that the developed mouse MAb should be hTERT specific and could not only recognize native cellular hTERT in ELISA and immunohistochemistry, but also neutralize telomerase activities. Thus, it could be hoped that the antibody could be used in clinical diagnosis and treatment of cancers.


Subject(s)
Antibodies, Monoclonal , Telomerase/antagonists & inhibitors , Telomerase/immunology , Amino Acid Sequence , Animals , Antibodies, Monoclonal/genetics , Antibody Affinity , Antibody Specificity , Base Sequence , Cloning, Molecular , DNA/genetics , DNA-Binding Proteins , Epitopes , HeLa Cells , Humans , Hybridomas/immunology , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Variable Region/genetics , Immunohistochemistry , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Neutralization Tests , Telomerase/metabolism
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