ABSTRACT
Nucleus accumbens-associated protein-1 (NAC1) is a transcriptional repressor encoded by the NACC1 gene, which is amplified and overexpressed in various human cancers and plays critical roles in tumor development, progression, and drug resistance. NAC1 has therefore been explored as a potential therapeutic target for managing malignant tumors. However, effective approaches for effective targeting of this nuclear protein remain elusive. In this study, we identified a core unit consisting of Met7 and Leu90 in NAC1's N-terminal domain (amino acids 1-130), which is critical for its homodimerization and stability. Furthermore, using a combination of computational analysis of the NAC1 dimerization interface and high-throughput screening (HTS) for small molecules that inhibit NAC1 homodimerization, we identified a compound (NIC3) that selectively binds to the conserved Leu-90 of NAC1 and prevents its homodimerization, leading to proteasomal NAC1 degradation. Moreover, we demonstrate that NIC3-mediated down-regulation of NAC1 protein sensitizes drug-resistant tumor cells to conventional chemotherapy and enhances the antimetastatic effect of the antiangiogenic agent bevacizumab both in vitro and in vivo These results suggest that small-molecule inhibitors of NAC1 homodimerization may effectively sensitize cancer cells to some anticancer agents and that NAC1 homodimerization could be further explored as a potential therapeutic target in the development of antineoplastic agents.
Subject(s)
Acetamides/pharmacology , Antineoplastic Agents/pharmacology , Biphenyl Compounds/pharmacology , Breast Neoplasms/drug therapy , Drug Resistance, Neoplasm/drug effects , Neoplasm Proteins/chemistry , Protein Multimerization/drug effects , Repressor Proteins/chemistry , Small Molecule Libraries/pharmacology , Angiogenesis Inhibitors/pharmacology , Animals , Apoptosis , Bevacizumab/pharmacology , Bone Neoplasms/drug therapy , Bone Neoplasms/metabolism , Bone Neoplasms/secondary , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Proliferation , Female , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Lung Neoplasms/secondary , Mice , Mice, Inbred NOD , Mice, SCID , Neoplasm Proteins/metabolism , Repressor Proteins/metabolism , Tumor Cells, Cultured , Xenograft Model Antitumor AssaysABSTRACT
BACKGROUND: Non-syndromic cleft lip with or without cleft palate (NSCL/P) is among the most common congenital malformations. The etiology of NSCL/P remains poorly characterized owing to its complex genetic heterogeneity. The objective of this study was to identify genetic variants that increase susceptibility to NSCL/P. MATERIAL AND METHODS: Whole-exome sequencing (WES) was performed in 8 fetuses with NSCL/P in China. Bioinformatics analysis was performed using commercially available software. Variants detected by WES were validated by Sanger sequencing. RESULTS: By filtering out synonymous variants in exons, we identified average 8575 nonsynonymous single nucleotide variants (SNVs). We subsequently compared the SNVs against public databases including NCBI dbSNP build 135 and 1000 Genomes Project and obtained an average of 203 SNVs. Total 12 reported candidate genes were verified by Sanger sequencing. Sanger sequencing also confirmed 16 novel SNVs shared by two or more samples. CONCLUSIONS: We have found and confirmed 16 susceptibility genes responsible for NSCL/P, which may play important role in the etiology of NSCL/P. The susceptibility genes identified in this study will not only be useful in revealing the etiology of NSCL/P but also in diagnosis and treatment of the patients with NSCL/P
Subject(s)
Female , Humans , Male , Genetic Predisposition to Disease , Cleft Lip/diagnosis , Cleft Lip/etiology , Cleft Lip/genetics , Exome/genetics , Cleft Palate/genetics , Computational Biology/methods , Computational Biology/standards , Bioethics/trends , Genomics/methods , Analysis of VarianceABSTRACT
BACKGROUND: Non-syndromic cleft lip with or without cleft palate (NSCL/P) is among the most common congenital malformations. The etiology of NSCL/P remains poorly characterized owing to its complex genetic heterogeneity. The objective of this study was to identify genetic variants that increase susceptibility to NSCL/P. MATERIAL AND METHODS: Whole-exome sequencing (WES) was performed in 8 fetuses with NSCL/P in China. Bioinformatics analysis was performed using commercially available software. Variants detected by WES were validated by Sanger sequencing. RESULTS: By filtering out synonymous variants in exons, we identified average 8575 nonsynonymous single nucleotide variants (SNVs). We subsequently compared the SNVs against public databases including NCBI dbSNP build 135 and 1000 Genomes Project and obtained an average of 203 SNVs. Total 12 reported candidate genes were verified by Sanger sequencing. Sanger sequencing also confirmed 16 novel SNVs shared by two or more samples. CONCLUSIONS: We have found and confirmed 16 susceptibility genes responsible for NSCL/P, which may play important role in the etiology of NSCL/P. The susceptibility genes identified in this study will not only be useful in revealing the etiology of NSCL/P but also in diagnosis and treatment of the patients with NSCL/P.
Subject(s)
Cleft Lip/genetics , Cleft Palate/genetics , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Base Sequence , Exome , HumansABSTRACT
The objective of this study is to explore the diagnosis pattern of mid-trimester fetal chromosomal aneuploidy and its clinical applications. A large group of pregnant women (18-34 years) received dual serological screening. The elderly pregnant women, who were at high and critical risk and refused amniocentesis, underwent non-invasive detection of fetal DNA upon recommendation. Then, the pregnant women with positive non-invasive detection results received amniocentesis, amniotic cell culture, and karyotype analysis for confirmation. In total, 24,520 women and 629 elderly women (>35 years) received amniocentesis, amniotic cell culture, and karyotype analysis, and 1512 women received non-invasive detection of fetal DNA. A total of 275 women received invasive prenatal diagnosis. Seventeen cases of trisomy 21, 3 cases of trisomy 18, and 2 cases of sex chromosomal abnormality were diagnosed. The serological screening-gene detection-prenatal diagnosis for mid-trimester fetal chromosomal aneuploidy increased the detection rate, and decreased the frequency of invasive prenatal diagnosis.
Subject(s)
Chromosome Aberrations , Prenatal Diagnosis , Adolescent , Adult , Amniotic Fluid/cytology , Amniotic Fluid/metabolism , Aneuploidy , China , Chromosomes, Human, Pair 18 , Chromosomes, Human, Pair 21 , Female , Humans , Karyotyping , Pregnancy , Pregnancy Trimester, Second , Trisomy , Young AdultABSTRACT
Mutations in gap junction proteins encoding beta connexions are believed to be a major cause for congenital hearing loss. The purpose of this study was to do comparative analyses of frequencies of most prominent mutations responsible for congenital deafness. Using fluorescence PCR method, the entire coding region of GJB2 gene, GJB3 gene, and SLC26A4 was analyzed. Direct DNA sequencing was used to analyze mutations in these genes among unrelated 2,674 cases of newborns. Also, 12S rRNA mutation was also studied in these cases. In 2,674 cases of newborns from June 2013 to June 2014, found deafness mutation in 137 cases (5.12 % of carrier rate), carrying GJB2 mutations in 68 cases (2.54 % of carry rate), GJB3 mutations in 10 cases (0.37 % of carry rate), SLC26A4 mutations in 54 cases (2.02 % of carry rate), and mitochondrial 12S rRNA mutations in five cases (0.19 % of carry rate). The study concludes that GJB2 gene mutation is the most common and mitochondrial 12S rRNA mutations are the least common mutation for congenital hearing loss in Chinese newborns.
