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1.
Int J Biol Sci ; 19(6): 1764-1777, 2023.
Article in English | MEDLINE | ID: mdl-37063417

ABSTRACT

Sleeping Beauty (SB) insertional mutagenesis has been widely used for genome-wide functional screening in mouse models of human cancers, however, intertumor heterogeneity can be a major obstacle in identifying common insertion sites (CISs). Although previous algorithms have been successful in defining some CISs, they also miss CISs in certain situations. A major common characteristic of these previous methods is that they do not take tumor heterogeneity into account. However, intertumoral heterogeneity directly influences the sequence read number for different tumor samples and then affects CIS identification. To precisely detect and define cancer driver genes, we developed SB Digestor, a computational algorithm that overcomes biological heterogeneity to identify more potential driver genes. Specifically, we define the relationship between the sequenced read number and putative gene number to deduce the depth cutoff for each tumor, which can reduce tumor complexity and precisely reflect intertumoral heterogeneity. Using this new tool, we re-analyzed our previously published SB-based screening dataset and identified many additional potent drivers involved in Brca1-related tumorigenesis, including Arhgap42, Tcf12, and Fgfr2. SB Digestor not only greatly enhances our ability to identify and prioritize cancer drivers from SB tumors but also substantially deepens our understanding of the intrinsic genetic basis of cancer.


Subject(s)
DNA Transposable Elements , Neoplasms , Animals , Mice , Humans , DNA Transposable Elements/genetics , Neoplasms/genetics , Neoplasms/pathology , Mutagenesis, Insertional/genetics , Oncogenes , Disease Models, Animal , Transposases/genetics
2.
Brief Bioinform ; 24(2)2023 03 19.
Article in English | MEDLINE | ID: mdl-36806894

ABSTRACT

Bioinformatics analysis and visualization of high-throughput gene expression data require extensive computer programming skills, posing a bottleneck for many wet-lab scientists. In this work, we present an intuitive user-friendly platform for gene expression data analysis and visualization called FungiExpresZ. FungiExpresZ aims to help wet-lab scientists with little to no knowledge of computer programming to become self-reliant in bioinformatics analysis and generating publication-ready figures. The platform contains many commonly used data analysis tools and an extensive collection of pre-processed public ribonucleic acid sequencing (RNA-seq) datasets of many fungal species, including important human, plant and insect pathogens. Users may analyse their data alone or in combination with public RNA-seq data for an integrated analysis. The FungiExpresZ platform helps wet-lab scientists to overcome their limitations in genomics data analysis and can be applied to analyse data of any organism. FungiExpresZ is available as an online web-based tool (https://cparsania.shinyapps.io/FungiExpresZ/) and an offline R-Shiny package (https://github.com/cparsania/FungiExpresZ).


Subject(s)
Genomics , Software , Humans , Gene Expression Profiling , Data Analysis , RNA/genetics , Gene Expression
3.
PLoS Genet ; 18(1): e1010001, 2022 01.
Article in English | MEDLINE | ID: mdl-35007279

ABSTRACT

Invasive Pulmonary Aspergillosis, which is caused by the filamentous fungus Aspergillus fumigatus, is a life-threatening infection for immunosuppressed patients. Chromatin structure regulation is important for genome stability maintenance and has the potential to drive genome rearrangements and affect virulence and pathogenesis of pathogens. Here, we performed the first A. fumigatus global chromatin profiling of two histone modifications, H3K4me3 and H3K9me3, focusing on the two most investigated A. fumigatus clinical isolates, Af293 and CEA17. In eukaryotes, H3K4me3 is associated with active transcription, while H3K9me3 often marks silent genes, DNA repeats, and transposons. We found that H3K4me3 deposition is similar between the two isolates, while H3K9me3 is more variable and does not always represent transcriptional silencing. Our work uncovered striking differences in the number, locations, and expression of transposable elements between Af293 and CEA17, and the differences are correlated with H3K9me3 modifications and higher genomic variations among strains of Af293 background. Moreover, we further showed that the Af293 strains from different laboratories actually differ in their genome contents and found a frequently lost region in chromosome VIII. For one such Af293 variant, we identified the chromosomal changes and demonstrated their impacts on its secondary metabolites production, growth and virulence. Overall, our findings not only emphasize the influence of genome heterogeneity on A. fumigatus fitness, but also caution about unnoticed chromosomal variations among common laboratory strains.


Subject(s)
Aspergillus fumigatus/classification , Chromosomes, Fungal/genetics , Genetic Heterogeneity , Histones/metabolism , Pulmonary Aspergillosis/microbiology , Aspergillus fumigatus/genetics , Aspergillus fumigatus/isolation & purification , Chromatin , DNA Transposable Elements , Fungal Proteins/metabolism , Gene Expression Regulation, Plant , Genetic Fitness , Histone Code , Humans , Promoter Regions, Genetic , Secondary Metabolism , Virulence
4.
Theranostics ; 11(20): 9967-9987, 2021.
Article in English | MEDLINE | ID: mdl-34815798

ABSTRACT

Background: BRCA1 plays critical roles in mammary gland development and mammary tumorigenesis. And loss of BRCA1 induces mammary tumors in a stochastic manner. These tumors present great heterogeneity at both intertumor and intratumor levels. Methods: To comprehensively elucidate the heterogeneity of BRCA1 deficient mammary tumors and the underlying mechanisms for tumor initiation and progression, we conducted bulk and single cell RNA sequencing (scRNA-seq) on both mammary gland cells and mammary tumor cells isolated from Brca1 knockout mice. Results: We found the BRCA1 deficient tumors could be classified into four subtypes with distinct molecular features and different sensitivities to anti-cancer drugs at the intertumor level. Whereas within the tumors, heterogeneous subgroups were classified mainly due to the different activities of cell proliferation, DNA damage response/repair and epithelial-to-mesenchymal transition (EMT). Besides, we reconstructed the BRCA1 related mammary tumorigenesis to uncover the transcriptomes alterations during this process via pseudo-temporal analysis of the scRNA-seq data. Furthermore, from candidate markers for BRCA1 mutant tumors, we discovered and validated one oncogene Mrc2, whose loss could reduce mammary tumor growth in vitro and in vivo. Conclusion: Our study provides a useful resource for better understanding of mammary tumorigenesis induced by BRCA1 deficiency.


Subject(s)
BRCA1 Protein/genetics , Breast Neoplasms/genetics , Carcinogenesis/genetics , Animals , BRCA1 Protein/metabolism , Breast/pathology , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Cell Transformation, Neoplastic/genetics , DNA Repair/genetics , Epithelial-Mesenchymal Transition/genetics , Female , Gene Expression/genetics , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic/genetics , Genes, BRCA1/physiology , Genetic Heterogeneity , Humans , Mammary Neoplasms, Animal/genetics , Mammary Neoplasms, Animal/pathology , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Sequence Analysis, RNA/methods , Single-Cell Analysis/methods , Transcriptome/genetics
5.
Biomaterials ; 272: 120756, 2021 05.
Article in English | MEDLINE | ID: mdl-33798959

ABSTRACT

Mesenchymal stem cells (MSCs) derived from somatic tissues have been used to promote lipotransfer, a common practice in cosmetic surgery. However, the effect of lipotransfer varies, and the mechanism of action remains vague. To address these questions, we differentiated human embryonic stem cells, a stable and unlimited source, into MSCs (EMSCs). Then we subcutaneously transplanted human fat aspirates together with EMSCs or PBS as a control into the back of nude mice. Within 24 h of transplantation, EMSCs promoted aggregation and encapsulation of injected fat tissues. Afterward, all grafts gradually shrank. However, EMSC-containing grafts were larger, heavier and had fewer dark areas on the surface than the control grafts. Histologically, more live adipocytes, vascular cells, and macrophages and less fibrosis were observed in EMSC-containing grafts than in the controls. Some EMSCs differentiated into vascular cells and adipocytes in the EMSC-containing grafts. RNA sequencing revealed that human RNA was shown to decline rapidly, while mouse RNA increased in the grafts; further, human genes related to extracellular matrix remodeling, adipogenesis, and chemokine (including CCL2) signaling were expressed at higher levels in the EMSC-containing grafts than they were in the controls. CCL2 knockout reduced macrophage migration towards EMSCs in vitro and early macrophage recruitment to the grafts and the pro-engraftment effect of EMSCs in vivo. Treating mice with a macrophage inhibitor abolished the EMSC effects and converted the grafts to heavy masses of cell debris. Together, these data demonstrate that EMSCs promote fat engraftment via enhanced tissue reconstitution and encapsulation of implanted tissues, which was followed by increased angiogenesis and adipocyte survival and reduced fibrosis, in which stimulated CCL2 signaling and mobilized macrophages play pivotal roles.


Subject(s)
Mesenchymal Stem Cells , Adipocytes , Animals , Cell Differentiation , Chemokine CCL2/genetics , Humans , Macrophages , Mice , Mice, Nude
6.
Theranostics ; 11(5): 2442-2459, 2021.
Article in English | MEDLINE | ID: mdl-33500735

ABSTRACT

Cancer growth is usually accompanied by metastasis which kills most cancer patients. Here we aim to study the effect of cisplatin at different doses on breast cancer growth and metastasis. Methods: We used cisplatin to treat breast cancer cells, then detected the migration of cells and the changes of epithelial-mesenchymal transition (EMT) markers by migration assay, Western blot, and immunofluorescent staining. Next, we analyzed the changes of RNA expression of genes by RNA-seq and confirmed the binding of activating transcription factor 3 (ATF3) to cytoskeleton related genes by ChIP-seq. Thereafter, we combined cisplatin and paclitaxel in a neoadjuvant setting to treat xenograft mouse models. Furthermore, we analyzed the association of disease prognosis with cytoskeletal genes and ATF3 by clinical data analysis. Results: When administered at a higher dose (6 mg/kg), cisplatin inhibits both cancer growth and metastasis, yet with strong side effects, whereas a lower dose (2 mg/kg) cisplatin blocks cancer metastasis without obvious killing effects. Cisplatin inhibits cancer metastasis through blocking early steps of EMT. It antagonizes transforming growth factor beta (TGFß) signaling through suppressing transcription of many genes involved in cytoskeleton reorganization and filopodia formation which occur early in EMT and are responsible for cancer metastasis. Mechanistically, TGFß and fibronectin-1 (FN1) constitute a positive reciprocal regulation loop that is critical for activating TGFß/SMAD3 signaling, which is repressed by cisplatin induced expression of ATF3. Furthermore, neoadjuvant administration of cisplatin at 2 mg/kg in conjunction with paclitaxel inhibits cancer growth and blocks metastasis without causing obvious side effects by inhibiting colonization of cancer cells in the target organs. Conclusion: Thus, cisplatin prevents breast cancer metastasis through blocking early EMT, and the combination of cisplatin and paclitaxel represents a promising therapy for killing breast cancer and blocking tumor metastasis.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Breast Neoplasms/drug therapy , Cell Movement , Epithelial-Mesenchymal Transition , Lung Neoplasms/drug therapy , Animals , Apoptosis , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Proliferation , Cisplatin/administration & dosage , Female , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/secondary , Mice , Mice, Nude , Paclitaxel/administration & dosage , Signal Transduction , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
7.
mBio ; 13(1): e0373421, 2021 02 22.
Article in English | MEDLINE | ID: mdl-35164551

ABSTRACT

Carbon catabolite repression (CCR) is a common phenomenon of microorganisms that enable efficient utilization of carbon nutrients, critical for the fitness of microorganisms in the wild and for pathogenic species to cause infection. In most filamentous fungal species, the conserved transcription factor CreA/Cre1 mediates CCR. Previous studies demonstrated a primary function for CreA/Cre1 in carbon metabolism; however, the phenotype of creA/cre1 mutants indicated broader roles. The global function and regulatory mechanism of this wide-domain transcription factor has remained elusive. Here, we applied two powerful genomics methods (transcriptome sequencing and chromatin immunoprecipitation sequencing) to delineate the direct and indirect roles of Aspergillus nidulans CreA across diverse physiological processes, including secondary metabolism, iron homeostasis, oxidative stress response, development, N-glycan biosynthesis, unfolded protein response, and nutrient and ion transport. The results indicate intricate connections between the regulation of carbon metabolism and diverse cellular functions. Moreover, our work also provides key mechanistic insights into CreA regulation and identifies CreA as a master regulator controlling many transcription factors of different regulatory networks. The discoveries for this highly conserved transcriptional regulator in a model fungus have important implications for CCR in related pathogenic and industrial species. IMPORTANCE The ability to scavenge and use a wide range of nutrients for growth is crucial for microorganisms' survival in the wild. Carbon catabolite repression (CCR) is a transcriptional regulatory phenomenon of both bacteria and fungi to coordinate the expression of genes required for preferential utilization of carbon sources. Since carbon metabolism is essential for growth, CCR is central to the fitness of microorganisms. In filamentous fungi, CCR is mediated by the conserved transcription factor CreA/Cre1, whose function in carbon metabolism has been well established. However, the global roles and regulatory mechanism of CreA/Cre1 are poorly defined. This study uncovers the direct and indirect functions of CreA in the model organism Aspergillus nidulans over diverse physiological processes and development and provides mechanistic insights into how CreA controls different regulatory networks. The work also reveals an interesting functional divergence between filamentous fungal and yeast CreA/Cre1 orthologues.


Subject(s)
Aspergillus nidulans , Catabolite Repression , Fungal Proteins/genetics , Aspergillus nidulans/genetics , Repressor Proteins/genetics , Transcription Factors/metabolism , Homeostasis , Carbon/metabolism , Gene Expression Regulation, Fungal
8.
Comput Struct Biotechnol J ; 18: 2610-2620, 2020.
Article in English | MEDLINE | ID: mdl-33033581

ABSTRACT

Gastric neuroendocrine carcinoma (GNEC) is rare cancer detected in the stomach. Previously, we demonstrated that the poorer prognosis of GNEC patients compared with gastric adenocarcinoma (GAC) patients was probably due to the lack of response to chemotherapy. Thus, it is crucial to study the specific GNEC gene expression pattern and investigate chemoresistance mechanism of GNEC. The transcriptome of GNEC patients was compared with that of GAC patients using RNA-seq. The KEGG analysis was employed to explore the specific differential expression gene function enrichment pattern. In addition, the transcriptomes of two GNEC cell lines, ECC10 and ECC12, were also compared with those of two GAC cell lines, MGC-803 and AGS, using RNA-seq. Comparing patient samples and cell lines transcriptome data, we try to uncover the potential targets and pathways which may affect the chemoresistance of GNEC. By combing all transcriptome data, we identified 22 key genes that were specifically up-regulated in GNEC. This panel of genes probably involves in the chemoresistance of GNEC. From our current experimental data, NeuroD1, one of the 22 genes, is associated with the prognosis of GNEC patients. Knockdown of NeuroD1 enhanced the sensitivity to irinotecan of GNEC cell lines. Our research sheds light in identifying a panel of novel therapeutic target specifically for GNEC clinical treatment which has not been reported before.

9.
Nat Commun ; 11(1): 3256, 2020 06 26.
Article in English | MEDLINE | ID: mdl-32591500

ABSTRACT

BRCA1 mutation carriers have a higher risk of developing triple-negative breast cancer (TNBC), which is a refractory disease due to its non-responsiveness to current clinical targeted therapies. Using the Sleeping Beauty transposon system in Brca1-deficient mice, we identified 169 putative cancer drivers, among which Notch1 is a top candidate for accelerating TNBC by promoting the epithelial-mesenchymal transition (EMT) and regulating the cell cycle. Activation of NOTCH1 suppresses mitotic catastrophe caused by BRCA1 deficiency by restoring S/G2 and G2/M cell cycle checkpoints, which may through activation of ATR-CHK1 signalling pathway. Consistently, analysis of human breast cancer tissue demonstrates NOTCH1 is highly expressed in TNBCs, and the activated form of NOTCH1 correlates positively with increased phosphorylation of ATR. Additionally, we demonstrate that inhibition of the NOTCH1-ATR-CHK1 cascade together with cisplatin synergistically kills TNBC by targeting the cell cycle checkpoint, DNA damage and EMT, providing a potent clinical option for this fatal disease.


Subject(s)
BRCA1 Protein/deficiency , Carcinogenesis/pathology , Receptor, Notch1/metabolism , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Alleles , Animals , Ataxia Telangiectasia Mutated Proteins/metabolism , BRCA1 Protein/metabolism , Cell Death , Cell Line, Tumor , Checkpoint Kinase 1/metabolism , DNA Transposable Elements/genetics , Disease Progression , Epithelial-Mesenchymal Transition , Female , Gene Expression Regulation, Neoplastic , Humans , Mice, Knockout , Mitosis , Mutation/genetics , Signal Transduction , Triple Negative Breast Neoplasms/genetics
10.
Cancer Lett ; 436: 28-37, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30118842

ABSTRACT

PTEN is a tumor suppressor found mutated in many cancers. From a synthetic lethality drug screen with PTEN-isogenic colorectal cancer cells, we found that mutant-PTEN cells were resistant to dual inhibitors of FLT3 and aurora kinase-A, including KW2449 and ENMD-2076. KW2449 significantly reduced the viability of wildtype-PTEN cells causing apoptosis, while little effect was observed in mutant-PTEN counterparts. Transcriptome profiling showed that members of PI3K-AKT signaling pathway were strongly changed in cells after KW2449 treatment, indicating a potential role of the pathway in drug resistance. We found that KW2449 caused a dose-dependent, biphasic induction of AKT phosphorylation at Ser473 in mutant-PTEN cells. Co-treatment with the inhibitors of its upstream signaling completely abolished the reactivation of AKT phosphorylation by KW2449 and reversed the drug resistant phenotype. These data suggest that reactivation of AKT phosphorylation at Ser473 is a key factor to confer drug resistant phenotype of mutant-PTEN cells to the dual inhibitors and that proper drug combinations that shut down AKT reactivation is necessary for the effective treatment of mutant-PTEN cancer with the dual inhibitors in clinical settings.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Colorectal Neoplasms/drug therapy , Drug Resistance, Neoplasm/drug effects , Indazoles/pharmacology , PTEN Phosphohydrolase/deficiency , Piperazines/pharmacology , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Animals , Aurora Kinase A/antagonists & inhibitors , Aurora Kinase A/genetics , Aurora Kinase A/metabolism , Cell Line, Tumor , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Drug Resistance, Neoplasm/genetics , Female , HCT116 Cells , Humans , Indazoles/administration & dosage , Mice, Nude , Mutation , PTEN Phosphohydrolase/genetics , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Piperazines/administration & dosage , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Pyrazoles/administration & dosage , Pyrimidines/administration & dosage , Signal Transduction/drug effects , Signal Transduction/genetics , Xenograft Model Antitumor Assays/methods , fms-Like Tyrosine Kinase 3/antagonists & inhibitors , fms-Like Tyrosine Kinase 3/genetics , fms-Like Tyrosine Kinase 3/metabolism
11.
Database (Oxford) ; 20182018 01 01.
Article in English | MEDLINE | ID: mdl-29992322

ABSTRACT

The identification and functional characterization of novel biomarkers in cancer requires survival analysis and gene expression analysis of both patient samples and cell line models. To help facilitate this process, we have developed KM-Express. KM-Express holds an extensive manually curated transcriptomic profile of 45 different datasets for prostate and breast cancer with phenotype and pathoclinical information, spanning from clinical samples to cell lines. KM-Express also contains The Cancer Genome Atlas datasets for 30 other cancer types with matching cell line expression data for 23 of them. We present KM-Express as a hypothesis generation tool for researchers to identify potential new prognostic RNA biomarkers as well as targets for further downstream functional cell-based studies. Specifically, KM-Express allows users to compare the expression level of genes in different groups of patients based on molecular, genetic, clinical and pathological status. Moreover, KM-Express aids the design of biological experiments based on the expression profile of the genes in different cell lines. Thus, KM-Express provides a one-stop analysis from bench work to clinical prospects. We have used this tool to successfully evaluate the prognostic potential of previously published biomarkers for prostate cancer and breast cancer. We believe KM-Express will accelerate the translation of biomedical research from bench to bed.Database URL: http://ec2-52-201-246-161.compute-1.amazonaws.com/kmexpress/index.php.


Subject(s)
Biomarkers, Tumor/genetics , Breast Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Internet , Prostatic Neoplasms/genetics , Software , Cell Line, Tumor , Databases, Genetic , Female , Humans , Male , Reproducibility of Results , Survival Analysis
12.
J Biol Chem ; 293(22): 8315-8329, 2018 06 01.
Article in English | MEDLINE | ID: mdl-29666189

ABSTRACT

The mammary gland is very intricately and well organized into distinct tissues, including epithelia, endothelia, adipocytes, and stromal and immune cells. Many mammary gland diseases, such as breast cancer, arise from abnormalities in the mammary epithelium, which is mainly composed of two distinct lineages, the basal and luminal cells. Because of the limitation of traditional transcriptome analysis of bulk mammary cells, the hierarchy and heterogeneity of mammary cells within these two lineages remain unclear. To this end, using single-cell RNA-Seq coupled with FACS analysis and principal component analysis, we determined gene expression profiles of mammary epithelial cells of virgin and pregnant mice. These analyses revealed a much higher heterogeneity among the mammary cells than has been previously reported and enabled cell classification into distinct subgroups according to signature gene markers present in each group. We also identified and verified a rare CDH5+ cell subpopulation within a basal cell lineage as quiescent mammary stem cells (MaSCs). Moreover, using pseudo-temporal analysis, we reconstructed the developmental trajectory of mammary epithelia and uncovered distinct changes in gene expression and in biological functions of mammary cells along the developmental process. In conclusion, our work greatly refines the resolution of the cellular hierarchy in developing mammary tissues. The discovery of CDH5+ cells as MaSCs in these tissues may have implications for our understanding of the initiation, development, and pathogenesis of mammary tumors.


Subject(s)
Cell Lineage , Epithelial Cells/cytology , Epithelial Cells/metabolism , High-Throughput Nucleotide Sequencing/methods , Mammary Glands, Animal/cytology , Mammary Glands, Animal/metabolism , Single-Cell Analysis/methods , Animals , Biomarkers/metabolism , Cell Differentiation , Cells, Cultured , Female , Gene Expression Profiling , Mice , Stem Cells/cytology , Stem Cells/metabolism , Transcriptome
13.
PLoS Genet ; 14(3): e1007270, 2018 03.
Article in English | MEDLINE | ID: mdl-29590106

ABSTRACT

The capacity to respond to temperature fluctuations is critical for microorganisms to survive within mammalian hosts, and temperature modulates virulence traits of diverse pathogens. One key temperature-dependent virulence trait of the fungal pathogen Candida albicans is its ability to transition from yeast to filamentous growth, which is induced by environmental cues at host physiological temperature. A key regulator of temperature-dependent morphogenesis is the molecular chaperone Hsp90, which has complex functional relationships with the transcription factor Hsf1. Although Hsf1 controls global transcriptional remodeling in response to heat shock, its impact on morphogenesis remains unknown. Here, we establish an intriguing paradigm whereby overexpression or depletion of C. albicans HSF1 induces morphogenesis in the absence of external cues. HSF1 depletion compromises Hsp90 function, thereby driving filamentation. HSF1 overexpression does not impact Hsp90 function, but rather induces a dose-dependent expansion of Hsf1 direct targets that drives overexpression of positive regulators of filamentation, including Brg1 and Ume6, thereby bypassing the requirement for elevated temperature during morphogenesis. This work provides new insight into Hsf1-mediated environmentally contingent transcriptional control, implicates Hsf1 in regulation of a key virulence trait, and highlights fascinating biology whereby either overexpression or depletion of a single cellular regulator induces a profound developmental transition.


Subject(s)
Candida albicans/growth & development , Candida albicans/pathogenicity , Genes, Fungal , HSP90 Heat-Shock Proteins/physiology , Heat Shock Transcription Factors/metabolism , Blotting, Western , Candida albicans/genetics , Chromatin Immunoprecipitation , Heat Shock Transcription Factors/genetics , Morphogenesis , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, RNA , Temperature , Virulence
14.
Nat Commun ; 8(1): 499, 2017 09 11.
Article in English | MEDLINE | ID: mdl-28894103

ABSTRACT

The capacity to coordinate environmental sensing with initiation of cellular responses underpins microbial survival and is crucial for virulence and stress responses in microbial pathogens. Here we define circuitry that enables the fungal pathogen Candida albicans to couple cell cycle dynamics with responses to cell wall stress induced by echinocandins, a front-line class of antifungal drugs. We discover that the C. albicans transcription factor Cas5 is crucial for proper cell cycle dynamics and responses to echinocandins, which inhibit ß-1,3-glucan synthesis. Cas5 has distinct transcriptional targets under basal and stress conditions, is activated by the phosphatase Glc7, and can regulate the expression of target genes in concert with the transcriptional regulators Swi4 and Swi6. Thus, we illuminate a mechanism of transcriptional control that couples cell wall integrity with cell cycle regulation, and uncover circuitry governing antifungal drug resistance.Cas5 is a transcriptional regulator of responses to cell wall stress in the fungal pathogen Candida albicans. Here, Xie et al. show that Cas5 also modulates cell cycle dynamics and responses to antifungal drugs.


Subject(s)
Candida albicans/genetics , Cell Cycle Checkpoints/genetics , Drug Resistance, Fungal/genetics , Gene Expression Regulation, Fungal/genetics , Transcription Factors/genetics , Antifungal Agents/pharmacology , Blotting, Western , Candida albicans/drug effects , Candida albicans/metabolism , Cell Wall/genetics , Cell Wall/metabolism , Echinocandins/pharmacology , Gene Expression Regulation, Fungal/drug effects , Microbial Sensitivity Tests , Mutation , Phosphorylation , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/metabolism , beta-Glucans/metabolism
15.
Biomaterials ; 133: 275-286, 2017 07.
Article in English | MEDLINE | ID: mdl-28460350

ABSTRACT

Human stem cells are vulnerable to unfavorable conditions, and their transportation relies on costly and inconvenient cryopreservation. We report here that human mesenchymal stem cells (MSC) in spheroids survived ambient conditions (AC) many days longer than in monolayer. Under AC, the viability of MSC in spheroids remained >90% even after seven days, whereas MSC in monolayer mostly died fast. AC-exposed MSC spheroids, after recovery under normal monolayer culture conditions with controlled carbon dioxide and humidity contents, resumed typical morphology and proliferation, and retained differentiating and immunosuppressive capabilities. RNA-sequencing and other assays demonstrate that reduced cell metabolism and proliferation correlates to the enhanced survival of AC-exposed MSC in spheroids versus monolayer. Moreover, AC-exposed MSC, when injected as either single cells or spheroids, retained therapeutic effects in vivo in mouse colitis models. Spheroidal formation also prolonged survival and sustained pluripotency of human embryonic stem cells kept under AC. Therefore, this work offers an alternative and relatively simple method termed spheropreservation versus the conventional method cryopreservation. It shall remarkably simplify long-distance transportation of stem cells of these and probably also other types within temperature-mild areas, and facilitate therapeutic application of MSC as spheroids without further processing.


Subject(s)
Cell Culture Techniques/methods , Spheroids, Cellular/cytology , Stem Cells/cytology , Cell Proliferation/physiology , Cell Survival/physiology , Cells, Cultured , Humans , Mesenchymal Stem Cells/cytology
16.
Nat Commun ; 7: 11704, 2016 05 26.
Article in English | MEDLINE | ID: mdl-27226156

ABSTRACT

Fever is a universal response to infection, and opportunistic pathogens such as Candida albicans have evolved complex circuitry to sense and respond to heat. Here we harness RNA-seq and ChIP-seq to discover that the heat shock transcription factor, Hsf1, binds distinct motifs in nucleosome-depleted promoter regions to regulate heat shock genes and genes involved in virulence in C. albicans. Consequently, heat shock increases C. albicans host cell adhesion, damage and virulence. Hsf1 activation depends upon the molecular chaperone Hsp90 under basal and heat shock conditions, but the effects are opposite and in part controlled at the level of Hsf1 expression and DNA binding. Finally, we demonstrate that Hsp90 regulates global transcription programs by modulating nucleosome levels at promoters of stress-responsive genes. Thus, we describe a mechanism by which C. albicans responds to temperature via Hsf1 and Hsp90 to orchestrate gene expression and chromatin architecture, thereby enabling thermal adaptation and virulence.


Subject(s)
Candida albicans/genetics , Chromatin/genetics , Fungal Proteins/genetics , Gene Expression Regulation, Fungal , HSP90 Heat-Shock Proteins/genetics , Heat Shock Transcription Factors/genetics , Animals , Binding Sites/genetics , Candida albicans/metabolism , Candida albicans/pathogenicity , Chromatin/metabolism , Fungal Proteins/metabolism , HSP90 Heat-Shock Proteins/metabolism , Heat Shock Transcription Factors/metabolism , Hot Temperature , Moths/microbiology , Nucleosomes/genetics , Nucleosomes/metabolism , Promoter Regions, Genetic/genetics , Temperature , Virulence/genetics , Zebrafish/microbiology
17.
Sci Rep ; 5: 11566, 2015 Jun 23.
Article in English | MEDLINE | ID: mdl-26099452

ABSTRACT

Ovarian cancer remains a dismal disease with diagnosing in the late, metastatic stages, therefore, there is a growing realization of the critical need to develop effective biomarkers for understanding underlying mechanisms. Although existing evidences demonstrate the important role of the single genetic abnormality in pathogenesis, the perturbations of interactors in the complex network are often ignored. Moreover, ovarian cancer diagnosis and treatment still exist a large gap that need to be bridged. In this work, we adopted a network-based survival-associated approach to capture a 12-gene network module based on differential co-expression PPI network in the advanced-stage, high-grade ovarian serous cystadenocarcinoma. Then, regulatory genes (protein-coding genes and non-coding genes) direct interacting with the module were found to be significantly overlapped with cell death genes. More importantly, these overlapping genes tightly clustered together pointing to the module, deciphering the crosstalk between network-based survival-associated module and cell death in ovarian cancer.


Subject(s)
Biomarkers, Tumor/genetics , Gene Regulatory Networks , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Cell Death/genetics , Databases, Genetic , Female , Gene Expression Regulation, Neoplastic , Humans , Kaplan-Meier Estimate , Multivariate Analysis , Neoplasm Grading , Proportional Hazards Models , Reproducibility of Results , Risk Factors , Treatment Outcome
18.
Nucleic Acids Res ; 43(Database issue): D578-82, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25274736

ABSTRACT

Increasing evidence reveals that diverse non-coding RNAs (ncRNAs) play critically important roles in viral infection. Viruses can use diverse ncRNAs to manipulate both cellular and viral gene expression to establish a host environment conducive to the completion of the viral life cycle. Many host cellular ncRNAs can also directly or indirectly influence viral replication and even target virus genomes. ViRBase (http://www.rna-society.org/virbase) aims to provide the scientific community with a resource for efficient browsing and visualization of virus-host ncRNA-associated interactions and interaction networks in viral infection. The current version of ViRBase documents more than 12,000 viral and cellular ncRNA-associated virus-virus, virus-host, host-virus and host-host interactions involving more than 460 non-redundant ncRNAs and 4400 protein-coding genes from between more than 60 viruses and 20 hosts. Users can query, browse and manipulate these virus-host ncRNA-associated interactions. ViRBase will be of help in uncovering the generic organizing principles of cellular virus-host ncRNA-associated interaction networks in viral infection.


Subject(s)
Databases, Genetic , RNA, Untranslated/metabolism , Virus Diseases/genetics , Virus Diseases/virology , Binding Sites , Internet , Proteins/metabolism , Virus Diseases/metabolism , Viruses/metabolism
19.
Biomed Res Int ; 2014: 475379, 2014.
Article in English | MEDLINE | ID: mdl-25133163

ABSTRACT

The formation and death of macrophages and foam cells are one of the major factors that cause coronary heart disease (CHD). In our study, based on the Edinburgh Human Metabolic Network (EHMN) metabolic network, we built an enzyme network which was constructed by enzymes (nodes) and reactions (edges) called the Edinburgh Human Enzyme Network (EHEN). By integrating the subcellular location information for the reactions and refining the protein-reaction relationships based on the location information, we proposed a computational approach to select modules related to programmed cell death. The identified module was in the EHEN-mitochondria (EHEN-M) and was confirmed to be related to programmed cell death, CHD pathogenesis, and lipid metabolism in the literature. We expected this method could analyze CHD better and more comprehensively from the point of programmed cell death in subnetworks.


Subject(s)
Apoptosis , Coronary Disease/metabolism , Coronary Disease/pathology , Metabolic Networks and Pathways , Coronary Disease/enzymology , Genes, Reporter , Humans , Molecular Sequence Annotation , Scotland
20.
Biomed Res Int ; 2014: 690103, 2014.
Article in English | MEDLINE | ID: mdl-24949464

ABSTRACT

Cell death is a critical biological process, serving many important functions within multicellular organisms. Aberrations in cell death can contribute to the pathology of human diseases. Significant progress made in the research area enormously speeds up our understanding of the biochemical and molecular mechanisms of cell death. According to the distinct morphological and biochemical characteristics, cell death can be triggered by extrinsic or intrinsic apoptosis, regulated necrosis, autophagic cell death, and mitotic catastrophe. Nevertheless, the realization that all of these efforts seek to pursue an effective treatment and cure for the disease has spurred a significant interest in the development of promising biomarkers of cell death to early diagnose disease and accurately predict disease progression and outcome. In this review, we summarize recent knowledge about cell death, survey current and emerging biomarkers of cell death, and discuss the relationship with human diseases.


Subject(s)
Apoptosis/genetics , Autophagy/genetics , Biomarkers , Humans , Mitosis , Necrosis/genetics
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