Tandem Mass Tag-Labeled Quantitative Proteome Analyses Identify C1R and A2M as Novel Serum Biomarkers in Pregnant Women with Obstructive Sleep Apnea.

The aim of this study was to identify serum diagnostic biomarkers associated with the severity of obstructive sleep apnea (OSA) during pregnancy. Differentially expressed proteins (DEPs) were identified in the control (C), mild (O), and moderate (MO) OSA groups (n = 3 in each group). Bioinformatics analysis was conducted to identify the underlying functions, pathways, and networks of the proteins. Receiver operating characteristic curves were used to assess the diagnostic value of the identified DEPs. The enzyme-linked immunoassay was performed to detect serum levels of the complement C1r subcomponent (C1R) and alpha-2-macroglobulin (A2M) in 79 pregnant women with OSA (mild OSA [n = 32]; moderate OSA [n = 29], and severe OSA [n = 18]) and 65 healthy pregnant women without OSA. Pearson's correlation analysis was conducted to analyze the correlation between C1R and A2M levels and OSA clinicopathological factors. In total, 141 DEPs, 29 DEPs, and 103 DEPs were identified in the three groups (i.e., the mild OSA vs control group, the moderate OSA vs mild apnea group, and the moderate OSA vs control group, respectively). C1R and A2M were identified as continuously up-regulated proteins, and the levels of C1R and A2M were associated with OSA severity. C1R and A2M were found to be correlated with body mass index, systolic blood pressure, apnea-hypopnea index, oxygen desaturation index, time with saturation below 90%, and lowest SaO2. Adverse maternal and neonatal outcomes were observed in pregnant women with OSA. C1R and A2M have been identified as diagnostic biomarkers and are associated with the severity of OSA during pregnancy.

Imbalance of gut microbiota is involved in the development of chronic obstructive pulmonary disease: A review.

Chronic obstructive pulmonary disease (COPD) is a common chronic disease characterized by chronic airway inflammation and remodeling, which seriously endangers human health. Recent developments in genomics and metabolomics have revealed the roles of the gut microbiota and its metabolites in COPD. Dysbiosis of the gut microbiota directly increases gut permeability, thereby promoting the translocation of pathological bacteria. The gut microbiota and associated metabolites may influence the development and progression of COPD by modulating immunity and inflammation. Furthermore, the systemic hypoxia and oxidative stress that occur in COPD may also be involved in intestinal dysfunction. The cross-talk between the gut and lungs is known as the gut-lung axis; however, an overview of its mechanism is lacking. This review highlights the critical and complex interplay of gut microbiota and immune responses in the gut-lung axis, further explores possible links between the gut and lungs, and summarizes new interventions through diet, probiotics, vitamins, and fecal microbiota transplantation, which are critical to COPD.

Bioinformatics analysis of PLA2G7 as an immune-related biomarker in COPD by promoting expansion and suppressive functions of MDSCs.

BACKGROUND: Immune mechanism is involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, the exact immune pathogenesis still remains unclear. This study aimed to identify the immune-related biomarkers in COPD through bioinformatics analysis and its potential molecular mechanism. METHODS: GSE76925 was downloaded from Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened, and enrichment analysis was performed. Single sample gene enrichment analysis (ssGSEA) was conducted to score the infiltration levels of immune cells. Weighted gene co-expression network analysis (WGCNA) was applied to identify trait-related modules and to further determine the key module-related DEGs. Moreover, the correlations between the key genes and clinical parameters and infiltration levels of immune cells were analyzed. Furthermore, expression of the selected one key gene, PLA2G7, the frequency of MDSCs, and the expression of MDSCs-related immunosuppressive mediators were determined among healthy, smokers and COPD patients. Finally, effects of PLA2G7 abnormal expression on the frequency of MDSCs and the expression of MDSCs-related immunosuppressive mediators were examined. RESULTS: A total of 352 DEGs were observed. These DEGs were mainly related to RNA metabolism and positive regulation of organelle organization. In addition, the black module was the most correlated with COPD. Six key genes (ADAMDEC1, CCL19, CHIT1, MMP9, PLA2G7, and TM4SF19) were identified between the black module and DEGs. Serum Lp-PLA2 and mRNA levels of PLA2G7, MDSCs, and MDSCs-related immunosuppressive mediators were found to be upregulated in COPD patients compared to the controls. The expression of PLA2G7 represented positive impact on the frequency of MDSCs and the expression of MDSCs-related immunosuppressive mediators. CONCLUSION: PLA2G7 may serve as a potential immune-related biomarker contributing to the progression of COPD by promoting expansion and suppressive functions of MDSCs.

STAT3 regulates 5-Fu resistance in human colorectal cancer cells by promoting Mcl-1-dependent cytoprotective autophagy.

Chemoresistance to 5-fluorouracil (5-Fu)-based chemotherapy is one of the primary reasons for the failure of colorectal cancer (CRC) management. STAT3 can mediate tumor drug resistance through a variety of diverse mechanisms. Nonetheless, the underlying mechanisms of STAT3-induced 5-Fu resistance in CRC are still poorly understood. Here, we aimed to investigate the potential mechanism(s) of STAT3-induced 5-Fu resistance in CRC. Quantitative RT-PCR and Western blot were used to test the expression of STAT3 and Mcl-1 in chemosensitive and chemoresistant CRC tissues and cell lines. After overexpression or knockdown of STAT3 or Mcl-1, and/or treatment with or without 5-Fu or chloroquine (CQ), we tested cell viability, inhibitory concentration 50% (IC50 ) value of 5-FU, cell apoptosis, proliferation, migration, and autophagy. STAT3 and Mcl-1 were significantly upregulated in the chemoresistant CRC tissues and cell lines, and STAT3 positively regulated Mcl-1. Functional studies demonstrated that STAT3 promoted 5-Fu resistance in CRC. Mechanistically, STAT3 triggered autophagy via Mcl-1 to induce cancer chemoresistance. Our results show that STAT3 regulates 5-Fu resistance in CRC by promoting Mcl-1-dependent cytoprotective autophagy. Our results provide a novel role of STAT3 and may offer a new approach for managing CRC 5-Fu resistance.

Clusterin as a serum biomarker candidate contributes to the lung fibroblasts activation in chronic obstructive pulmonary disease.

BACKGROUND: Fibrosis in the peripheral airways contributes to airflow limitation in patients with chronic obstructive pulmonary disease (COPD). However, the key proteins involved in its development are still poorly understood. Thus, we aimed to identify the differentially expressed proteins (DEPs) between smoker patients with and without COPD and elucidate the molecular mechanisms involved by investigating the effects of the identified biomarker candidate on lung fibroblasts. METHODS: The potential DEPs were identified by isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis. The messenger RNA and protein levels of clusterin (CLU) in COPD patients and 12% cigarette smoke extract (CSE)-treated human bronchial epithelial cells were determined at the indicated time points. Furthermore, an in vitro COPD model was established via the administration of 8% CSE to normal human lung fibroblasts (NHLFs) at indicated time points. The effects of CSE treatment and CLU silencing on proliferation and activation of lung fibroblasts were analyzed. RESULTS: A total of 144 DEPs were identified between COPD patients and normal smokers. The iTRAQ-based proteomics and bioinformatics analyses identified CLU as a serum biomarker candidate. We also discovered that CLU levels were significantly increased ( P   <  0.0001) in Global Initiative for Obstructive Lung Disease II, III, and IV patients and correlated ( P   <  0.0001) with forced expiratory volume in 1 s ( R  = -0.7705), residual volume (RV) ( R  = 0.6281), RV/total lung capacity ( R  = 0.5454), and computerized tomography emphysema ( R  = 0.7878). Similarly, CLU levels were significantly increased in CSE-treated cells at indicated time points ( P  < 0.0001). The CSE treatment significantly inhibited the proliferation, promoted the inflammatory response, differentiation of NHLFs, and collagen matrix deposition, and induced the apoptosis of NHLFs; however, these effects were partially reversed by CLU silencing. CONCLUSION: Our findings suggest that CLU may play significant roles during airway fibrosis in COPD by regulating lung fibroblast activation.

IP3 R attenuates oxidative stress and inflammation damage in smoking-induced COPD by promoting autophagy.

Tobacco smoking is one of the most important risk factors for chronic obstructive pulmonary disease (COPD). However, the most critical genes and proteins remain poorly understood. Therefore, we aimed to investigate these hub genes and proteins in tobacco smoke-induced COPD, together with the potential mechanism(s). Differentially expressed genes (DEGs) were analysed between smokers and patients with COPD. mRNA expression and protein expression of IP3 R were confirmed in patients with COPD and extracted smoke solution (ESS)-treated human bronchial epithelial (HBE) cells. Moreover, expression of oxidative stress, inflammatory cytokines and/or autophagy-related protein was tested when IP3 R was silenced or overexpressed in ESS-treated and/or 3-MA-treated cells. A total of 30 DEGs were obtained between patients with COPD and smoker samples. IP3 R was identified as one of the key targets in tobacco smoke-induced COPD. In addition, IP3 R was significantly decreased in patients with COPD and ESS-treated cells. Loss of IP3 R statistically increased expression of oxidative stress and inflammatory cytokines in ESS-treated HBE cells, and overexpression of IP3 R reversed the above functions. Furthermore, the autophagy-related proteins (Atg5, LC3 and Beclin1) were statistically decreased, and p62 was increased by silencing of IP3 R cells, while overexpression of IP3 R showed contrary results. Additionally, we detected that administration of 3-MA significantly reversed the protective effects of IP3 R overexpression on ESS-induced oxidative stress and inflammatory injury. Our results suggest that IP3 R might exert a protective role against ESS-induced oxidative stress and inflammation damage in HBE cells. These protective effects might be associated with promoting autophagy.

Neurotrophic factor levels in the serum and cerebrospinal fluid of neonates infected with human cytomegalovirus.

Human cytomegalovirus (HCMV) is most likely to damage the central nervous system (CNS) during early embryonic development; however, the early neurodevelopmental abnormalities caused by HCMV infection and the regulation of cytokines remain unclear. Therefore, we investigated neuronal factors in the serum and cerebrospinal fluid (CSF) of newborns infected with HCMV using protein microarray technology with a view to elucidating the changes in specific neuronal factors for use in the development of a reliable index for predicting CNS injury caused by HCMV infection. Serum and CSF were collected from four newborns with HCMV infection and CNS injury (HCMV-infected group) and from four newborns without CNS infection (control group). A protein microarray containing 29 kinds of CNS-related cytokines was used to identify differentially expressed neuronal factors in the serum and CSF of the HCMV-infected and control groups. The levels of the differentially expressed proteins were verified further in 30 CSF samples from an HCMV-infected group using enzyme-linkedimmunosorbent assay (ELISA). Between newborns in the HCMV-infected and control groups, the protein microarray analysis identified three differentially expressed neurotrophic factors in the CSF samples: Acrp30, MMP-3, and interleukin-1 alpha (IL-1α). No differential cytokine expression was seen in the serum. ELISA showed significantly higher expression levels of Acrp30 and MMP-3 in the CSF of the 30 newborns with HCMV infection and CNS injury than in those in the control group, whereas the expression of IL-1α was significantly lower. Our results demonstrate that changes in the expression levels of Acrp30, MMP-3, and IL-1α in the CSF of newborns infected with HCMV may be related to the pathogenesis of CNS infection.

CX3CR1 Acts as a Protective Biomarker in the Tumor Microenvironment of Colorectal Cancer.

The tumor microenvironment (TME) plays an important role in the pathogenesis of many cancers. We aimed to screen the TME-related hub genes of colorectal adenoma (CRAD) and identify possible prognostic biomarkers. The gene expression profiles and clinical data of 464 CRAD patients in The Cancer Genome Atlas (TCGA) database were downloaded. The Estimation of STromal and Immune cells in MAlignant Tumours using Expression data (ESTIMATE) algorithm was performed to calculate the ImmuneScore, StromalScore, and EstimateScore. Thereafter, differentially expressed genes (DEGs) were screened. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and protein-protein interaction (PPI) analysis were performed to explore the roles of DEGs. Furthermore, univariate and multivariate Cox analyses were accomplished to identify independent prognostic factors of CRAD. CX3CR1 was selected as a hub gene, and the expression was confirmed in colorectal cancer (CRC) patients and cell lines. The correlations between CX3CR1 and tumor-infiltrating immune cells were estimated by Tumor IMmune Estimation Resource database (TIMER) and CIBERSORT analysis. Besides, we investigated the effects of coculture with THP-1-derived macrophages with HCT8 cells with low CX3CR1 expression on immune marker expression, cell viability, and migration. There were significant differences in the ImmuneScore and EstimateScore among different stages. Patients with low scores presented significantly lower lifetimes than those in the high-score group. Moreover, we recognized 1,578 intersection genes in ImmuneScore and StromalScore, and these genes were mainly enriched in numerous immune-related biological processes. CX3CR1 was found to be associated with immune cell infiltration levels, immune marker expression, and macrophage polarization. Simultaneous silencing of CX3CR1 and coculture with THP-1 cells further regulated macrophage polarization and promoted the cell proliferation and migration of CRC cells. CX3CR1 was decreased in CRAD tissues and cell lines and was related to T and N stages, tumor differentiation, and prognosis. Our results suggest that CX3CR1 contributes to the recruitment and regulation of immune-infiltrating cells and macrophage polarization in CRC and TAM-induced CRC progression. CX3CR1 may act as a prognostic biomarker in CRC.

Identification of key genes involved in JAK/STAT pathway in colorectal cancer.

JAK/STAT pathway has been well confirmed in the development of colorectal cancer (CRC), however, the exact mechanism is unclear. Therefore, we aimed to identify key genes involved in JAK/STAT pathway in CRC, as well as the potential mechanism. RT² profiler PCR arrays were performed to identify key genes of the JAK/STAT pathway. GO, KEGG pathway and PPI analyses were performed to screen the main functions of differentially expressed genes (DEGs). Moreover, the expression of DEGs was detected by GEPIA based on TCGA database and verified by qPCR and/or Western blot. Subsequently, the association between the two DEGs (CXCL9 and IL6ST) and clinicopathological features were determined by immunohistochemistry, and survival analysis was also conducted. Finally, the effects of IL6ST overexpression on STAT3 activation and HT29 cell functions were analyzed. A total of 14 DEGs were identified. Among the DEGs, GHR, NR3C1, IL6ST and A2M were confirmed to be statistically decreased, while CXCL9 was significantly increased in the CRC tissues. Furthermore, CXCL9 was significantly associated with differentiation, lymph node metastasis, distant metastasis and invasion, while IL6ST was related with tumor size, differentiation, stage and invasion. Patients with high expression of IL6ST presented significantly lower lifetime, however, CXCL9 showed the opposite results without significance. Additionally, we found that overexpression of IL6ST statistically elevated p-STAT3 level, cell viability, adhesion rate and migration, and decreased apoptosis, but had no effects on cell cycle. Our results suggest that IL6ST is a critical key gene involved in JAK/STAT signaling pathway in CRC.

Gene Expression Along with Genomic Copy Number Variation and Mutational Analysis Were Used to Develop a 9-Gene Signature for Estimating Prognosis of COAD.

PURPOSE: This study aims to systematically analyze multi-omics data to explore new prognosis biomarkers in colon adenocarcinoma (COAD). MATERIALS AND METHODS: Multi-omics data of COAD and clinical information were obtained from The Cancer Genome Atlas (TCGA). Univariate Cox analysis was used to select genes which significantly related to the overall survival. GISTIC 2.0 software was used to identify significant amplification or deletion. Mutsig 2.0 software was used to identify significant mutation genes. The 9-gene signature was screened by random forest algorithm and Cox regression analysis. GSE17538 dataset was used as an external dataset to verify the predictive ability of 9-gene signature. qPCR was used to detect the expression of 9 genes in clinical specimens. RESULTS: A total of 71 candidate genes are obtained by integrating genomic variation, mutation and prognostic data. Then, 9-gene signature was established, which includes HOXD12, RNF25, CBLN3, DOCK3, DNAJB13, PYGO2, CTNNA1, PTPRK, and NAT1. The 9-gene signature is an independent prognostic risk factor for COAD patients. In addition, the signature shows good predicting performance and clinical practicality in training set, testing set and external verification set. The results of qPCR based on clinical samples showed that the expression of HOXD12, RNF25, CBLN3, DOCK3, DNAJB13, and PYGO2 was increased in colon cancer tissues and the expression of CTNNA1, PTPRK, NAT1 was decreased in colon cancer tissues. CONCLUSION: In this study, 9-gene signature is constructed as a new prognostic marker to predict the survival of COAD patients.

Prediction of COVID-19 Severity Using Chest Computed Tomography and Laboratory Measurements: Evaluation Using a Machine Learning Approach.

BACKGROUND: Most of the mortality resulting from COVID-19 has been associated with severe disease. Effective treatment of severe cases remains a challenge due to the lack of early detection of the infection. OBJECTIVE: This study aimed to develop an effective prediction model for COVID-19 severity by combining radiological outcome with clinical biochemical indexes. METHODS: A total of 46 patients with COVID-19 (10 severe, 36 nonsevere) were examined. To build the prediction model, a set of 27 severe and 151 nonsevere clinical laboratory records and computerized tomography (CT) records were collected from these patients. We managed to extract specific features from the patients' CT images by using a recently published convolutional neural network. We also trained a machine learning model combining these features with clinical laboratory results. RESULTS: We present a prediction model combining patients' radiological outcomes with their clinical biochemical indexes to identify severe COVID-19 cases. The prediction model yielded a cross-validated area under the receiver operating characteristic (AUROC) score of 0.93 and an F1 score of 0.89, which showed a 6% and 15% improvement, respectively, compared to the models based on laboratory test features only. In addition, we developed a statistical model for forecasting COVID-19 severity based on the results of patients' laboratory tests performed before they were classified as severe cases; this model yielded an AUROC score of 0.81. CONCLUSIONS: To our knowledge, this is the first report predicting the clinical progression of COVID-19, as well as forecasting severity, based on a combined analysis using laboratory tests and CT images.

Single Cell RNA-seq Data Analysis Reveals the Potential Risk of SARS-CoV-2 Infection Among Different Respiratory System Conditions.

COVID-19 (Coronavirus Disease 2019) has been an ongoing pandemic, resulting in an increase in people being infected globally. Understanding the potential risk of infection for people under different respiratory system conditions is important and will help prevent disease spreading. We explored and collected five published and one unpublished single-cell respiratory system tissue transcriptome datasets, including idiopathic pulmonary fibrosis (IPF), aging lungs (mouse origin data), lung cancers, and smoked branchial epithelium, for specifically reanalyzing the ACE2 and TMPRSS2 expression profiles. Compared to normal people, we found that smoking and lung cancer increase the risk for COVID-19 infection due to a higher expression of ACE2 and TMPRSS2 in lung cells. Aged lung does not show increased risk for infection. IPF patients may have a lower risk for original COVID-19 infection due to lower expression in AT2 cells but may have a higher risk for severity due to a broader expression spectrum of TMPRSS2. Further investigation and validation on these cell types are required. Nonetheless, this is the first report to predict the risk and potential severity for COVID-19 infection for people with different respiratory system conditions. Our analysis is the first systematic description and analysis to illustrate how the underlying respiratory system conditions contribute to a higher infection risk.

STAT1 expression and HPV16 viral load predict cervical lesion progression.

Cervical cancer is the fourth leading cause of cancer-associated mortality worldwide. However, its underlying molecular mechanisms are unclear. It is important to explore these mechanisms in order to identify novel diagnostic and prognostic biomarkers. The present study determined the association between STAT1 and human papillomavirus (HPV)16 in cervical lesions. STAT1 expression was detected by immunohistochemistry. Quantitative PCR was used to detect HPV16 viral load and STAT1 expression in cervical lesions. The potential associations among STAT1 expression, HPV16 viral load and the severity of cervical lesions in patients were analyzed using receiver operating characteristic (ROC) curves. The Cancer Genome Atlas database was used to analyze STAT1 expression and survival. High STAT1 expression was observed in 10.71 (3/28), 41.18 (14/34), 53.06 (26/49) and 90.00% (27/30) of normal tissue, low-grade squamous intraepithelial lesion (LSIL), high-grade squamous intraepithelial lesion (HSIL) and cervical squamous cell carcinoma samples, respectively. The HPV16 copy number gradually increased with the progression of cervical lesions, with the highest copy number observed in cervical cancer samples. In addition, STAT1 expression was positively correlated with HPV16 viral load. Furthermore, ROC curve analysis demonstrated that the combination of STAT1 expression and HPV16 viral load was able to differentiate between LSIL/HSIL and cervical cancer samples. Bioinformatics analysis revealed that STAT1 expression was associated with improved survival in cervical cancer. Additionally, STAT1 expression was positively associated with the progression of cervical lesions, and HPV16 viral load may affect STAT1 expression. Overall, these findings indicate that STAT1 may be an indicator of the status of cervical lesions.

Bibliometric analysis of subject trends and knowledge structures of gut microbiota.

BACKGROUND: Gut microbiota is an emerging field of research, with related research having breakthrough development in the past 15 years. Bibliometric analysis can be applied to analyze the evolutionary trends and emerging hotspots in this field. AIM: To study the subject trends and knowledge structures of gut microbiota related research fields from 2004 to 2018. METHODS: The literature data on gut microbiota were identified and downloaded from the PubMed database. Through biclustering analysis, strategic diagrams, and social network analysis diagrams, the main trend and knowledge structure of research fields concerning gut microbiota were analyzed to obtain and compare the research hotspots in each period. RESULTS: According to the strategic coordinates and social relationship network map, Clostridium Infections/microbiology, Clostridium Infections/therapy, RNA, Ribosomal, 16S/genetics, Microbiota/genetics, Microbiota/immunology, Dysbiosis/immunology, Infla-mmation/immunology, Fecal Microbiota Transplantation/methods, Fecal Microbiota Transplantation can be used as an emerging research hotspot in the past 5 years (2014-2018). CONCLUSION: Some subjects were not yet fully studied according to the strategic coordinates; and the emerging hotspots in the social network map can be considered as directions of future research.

Electronic cigarettes: Emerging trends and research hotspots.

INTRODUCTION: Research on electronic cigarettes is an emerging field, with the number of articles in this field noted to have grown exponentially over recent years. We used a bibliometric analysis method (co-word analysis) to analyze the emerging trends and research hotspots in this field. METHODS: Publication data on electronic cigarettes from 2010 to 2018 were retrieved and downloaded from the PubMed database. Theme trends and knowledge structures were analyzed on the relevant research fields of electronic cigarettes by using a biclustering analysis, strategic diagram analysis, and social network analysis methods. Research hotspots were extracted and compared from three periods. RESULTS: Core topics that have continuously develop between the years 2010 and 2018 include: tobacco use cessation devices; tobacco products; tobacco use cessation devices/adverse effects; smoking prevention and adverse effects; electronic nicotine delivery systems/economics; and public health. Some currently undeveloped topics that could be considered as new future research directions include: tobacco use disorder/therapy; tobacco use disorder/epidemiology; students/psychology; students/statistics and numerical data; adolescent behavior/psychology; nicotine/toxicity; nicotinic agonists/administration and dosage; and electronic nicotine delivery systems/legislation and jurisprudence. CONCLUSIONS: Results suggest that some currently immature topics in strategic coordinates and emerging hotspots in social network graphs can be used as future research directions.

A Bibliometric Analysis of Cleft Lip and Palate-Related Publication Trends From 2000 to 2017.

OBJECTIVE: Cleft lip and palate (CLP) is the most common human cranial and maxillofacial birth defect. The aim of this bibliometric analysis was to provide an overview of the development of CLP-related research. METHOD: Cleft lip and palate-related studies published from 2000 to 2017 were retrieved from the Science Citation Index Expanded core database. Publication date, journal, authors, first authors, keywords, and citations were extracted and quantitatively analyzed using Bibliographic Item Co-Occurrence Matrix Builder software. The word matrix and co-occurrence matrix were established, and the co-citation analysis, keyword clustering, and social network analysis (SNA) of highly cited papers were completed. RESULTS: A total of 9040 articles were retrieved from the 18 years of publications that were searched. The number of documents steadily increased over the period of interest, with a slight decrease in 2016 and 2017. This article separately examined the top most cited papers and high-frequency keywords from 3 time periods: 2000 to 2005, 2006 to 2011, and 2011 to 2017. The strategy coordinates of citation reflect TGF-ß3, MSX1 gene, technique for cleft lip repair, TTF2, P63, IRF6 gene, FGF signaling, PVRL1, TGFBR2, and BMP4 gene as areas of research interest in the field. Moreover, the SNA of keywords highlighted new research topics: meta-analysis, cone beam computed tomography, tooth agenesis, case-control study, association study, micrognathia, DiGeorge syndrome, NSCL/P, UCLP, GWAS, MTHFR, and CLPTM1L. CONCLUSION: We conducted bibliometric research of CLP across an 18-year span. The results help to define an overall command of the latest topics in CLP and provide insight for launching new projects.