Screening small molecules and drugs for activity to modulate alternative splicing, we found that amiloride, distinct from four other intracellular pH-affecting analogues, could normalize the splicing of BCL-X, HIPK3 and RON/MISTR1 transcripts in human hepatocellular carcinoma Huh-7 cells. To elucidate the underlying mechanisms, our proteomic analyses of amiloride-treated cells detected hypo-phosphorylation of splicing factor SF2/ASF and also decreased levels of SRp20 and two un-identified SR proteins. We further observed decreased phosphorylation of AKT, ERK1/2 and PP1, while increased phosphorylation of p38 and JNK, suggesting that amiloride treatment down-regulated kinases and up-regulated phosphatases in the signal pathways known to affect the splicing factor protein phosphorylation. The amiloride effects of splicing factor protein hypo-phosphorylation andnormalizedoncogenic RNA splicing were both abrogated by pre-treatment with a PP1 inhibitor. We then performed global exon array analysis of Huh-7 cells treated with amiloride for 24 hours. Using gene array chips (Affymetrix GeneChip Human Exon 1.0 ST Array of >518000 exons of 42974 genes) for exon array analysis (set parameters of correlation coefficient 0.7, splicing index -1.585 , and log2 ratio -1.585), we found that amiloride influenced the splicing patterns of 551 genes involving at least 584 exons, which included 495 known protein-coding genes involving 526 exons, many of which play key roles in functional networks of ion transport, extracellular matrix, cytoskeletons and genome maintenance. Cellular functional analyses revealed subsequent invasion and migration defects, cell cycle disruption, cytokinesis impairment, and lethal DNA degradation in amiloride-treated Huh-7 cells. This study thus provides mechanistic underpinnings for exploiting small molecule modulation of abnormal RNA splicing for cancer therapeutics.
Small molecule amiloride modulates oncogenic RNA alternative splicing to devitalize human cancer cells.
Cell lineView Samples
Unr (upstream of N-ras) is a cytoplasmic RNA-binding protein with cold shock domains, involved in regulation of messenger RNA stability and translation. To address the biological role of Unr, we inactivated the unr gene by homologous recombination in mice and embryonic stem (ES) cells. Embryos deficient for Unr die at mid-gestation, and the main phenotypic defects observed, growth deficiency and absence of neural tube closure, suggest a role of Unr in the balance proliferation/differentiation during early development. Here, we report that in Unr-null ES cell cultures, we observed a greater proportion of partially differentiated colonies, together with dispersed, refractile cells with stellate morphology, reminiscent of primitive endoderm (PrE) cells. DNA microarray, immunostaining, and RNA analyses revealed that Unr-null ES cells express a set of PrE markers, including the GATA6 transcription factor, a key inducer of PrE. Although Unr-deficient cells did not downregulate the pluripotency regulators Oct4, Nanog and Sox2, they grew more slowly than the wild-type lines, and their clonogenicity was lower. Silencing of Unr by RNA interference in ES E14 (129 genetic background) resulted in similar phenotypic and molecular changes as those observed in unr-/- ES cells (C57Bl/6 background). Finally, we show that ectopic expression of Unr in unr-/- ES cells partially reverses the endoderm-specific gene expression and the differentiation phenotype.
The RNA-binding protein Unr prevents mouse embryonic stem cells differentiation toward the primitive endoderm lineage.
Specimen part, TreatmentView Samples
Muscle injury was elicited by cardiotoxin injection into the tibialis anterior muscle. Macrophages were isolated 2 days post-injury from the regenerating muscle.
Tissue LyC6- macrophages are generated in the absence of circulating LyC6- monocytes and Nur77 in a model of muscle regeneration.
Specimen partView Samples
Alternative splicing is a mechanism for increasing the protein variety of a limited number of genes. Studies have shown that aberrant regulations of the alternative splicing of apoptotic gene transcripts may contribute to the development of cancer. In this study, we isolated 4ß-Hydroxywithanolide E (4bHWE) from the traditional herb Physalis peruviana, and analyzed its biological effects in cancer cells. The results demonstrated that 4bHWE modulates the alternative splicing of apoptotic genes (e.g., HIPK3, SMAC/DIABLO, and SURVIVIN), changes the expression level of splicing factors (e.g., hnRNP C1/C2, ASF/SF2, SRp20, and SRp55), and induces histone tail posttranslational modifications (e.g., H3K27me1, H3K27me2, H3K36me3, and H3K79me1). Pretreatment with okadaic acid to inhibit protein phosphatase-1 could partly relieve the effects of 4bHWE on the alternative splicing of HIPK3 and SMAC/DIABLO transcripts, as well as on the dephosphorylation of ASF/SF2. Genome-wide detection of alternative splicing further indicated that several other apoptosis-related genes are also regulated by 4bHWE, including APAF1, CARP-1, and RIPK1. Moreover, we extended our study to apoptosis-associated molecules, detecting an increasing level of CASPASE-3 activity and cleavage of poly ADP-ribose polymerase in 4bHWE-induced apoptosis. Furthermore, in vivo experiments showed that the treatment of tumor-bearing mice with 4bHWE resulted in a marked decrease of tumor size and weight. Taken together, this study is the first to show that 4bHWE affects alternative splicing through the modulations of splicing factors, providing a novel view of the antitumor mechanism of 4bHWE. Overall design: Examination of the global genes with altered alternative splicing in 4bHWE-treated Huh-7 cells.
4β-Hydroxywithanolide E Modulates Alternative Splicing of Apoptotic Genes in Human Hepatocellular Carcinoma Huh-7 Cells.
Specimen part, Treatment, SubjectView Samples
The study demontrates differences in the transcriptome ( both of protein coding transcripts and long non-coding RNAs) in the unilateral ureteric obstruction model of renal fibrosis. Overall design: Renal tissue was studied from animals undergoing sham operation (as controls) or right ureteric ligation. Animals were sacrificed 2 and 8 days following ligation and the right kidney tissue was examined.
Whole-transcriptome analysis of UUO mouse model of renal fibrosis reveals new molecular players in kidney diseases.
Sex, Age, Specimen part, Cell line, SubjectView Samples
We demonstrate that GLUT4 up-regulation significantly increased cell migration and invasion in lower magligance head and neck cancer cell lines in vitro.
Glucose transporter 4 promotes head and neck squamous cell carcinoma metastasis through the TRIM24-DDX58 axis.
Specimen part, Cell lineView Samples
We report the expression profiles of MCF10A cells encapsulated in hydrogels of varying stiffness and composition. Cells were encapsulated for 7 days in either 1.) soft alginate and reconstituted basement membrane (rBM), 2.) stiff alginate and rBM, 3,) soft col-1 and rBM, or 4.) stiff col-1. We find global gene expression changes in response to enhanced ECM stiffness, independent of expression changes in response to col-1 exposure. These results provide a comprehensive study of the gene expression changes associated with increased ECM stiffness in addition to the gene expression changes associated with increased col-1 concentration in combination with, and independent of, ECM stiffness. Overall design: Expression profiling of MCF10A cells in four hydrogel conditions were sequenced in duplicate via Illumina HiSeq.
YAP-independent mechanotransduction drives breast cancer progression.
Specimen part, Cell line, SubjectView Samples
Tibialis anterior muscle was damaged by cardiotoxin injection and macrophage subsets were isolated and analyzed by gene expression analysis.
Highly Dynamic Transcriptional Signature of Distinct Macrophage Subsets during Sterile Inflammation, Resolution, and Tissue Repair.
The orthotopic transplantation of human OEC-M1 cells in immune-compromised mice was established to feasibly study tumorigenesis and lymph node metastasis of OSCC.
Insulin-like growth factor-independent insulin-like growth factor binding protein 3 promotes cell migration and lymph node metastasis of oral squamous cell carcinoma cells by requirement of integrin β1.
Specimen part, Cell lineView Samples
To exmaine the PTHLH stimulated genes in Ca9-22 cells, we preformed the Affymetrix Human Genome U133 Plus 2.0 Array with empty vector or PTHLH expression vector. The raw data were normalized by GeneSpring GX software and up-load with raw values.
Parathyroid Hormone-Like Hormone is a Poor Prognosis Marker of Head and Neck Cancer and Promotes Cell Growth via RUNX2 Regulation.
Cell lineView Samples