Weiren Huang

shRNA targeting long non-coding RNA CCAT2 controlled by tetracycline-inducible system inhibits progression of bladder cancer cells

Recent reports show that long non-coding RNAs (lncRNAs) are emerging as significant functional regulators in the development of tumors, including bladder cancer. Here, we found that CCAT2 was upregulated in bladder cancer tissues and cell lines. Through the statistical analyses, we also found that the high expression level of CCAT2 was positively correlated with histological grade and TNM stage of bladder cancer. Further experimental results revealed that knockdown of CCAT2 could decrease cell proliferation and migration as well as induce apoptosis in bladder cancer cells. Besides, using the post-transcriptional device of synthetic biology, we create the tetracycline-inducible double small hairpin RNAs (shRNAs) vector to control the expression level of CCAT2 which was induced by doxycycline in a dosage-dependent manner. In summary, our data indicated that CCAT2 may be an oncogene and a therapeutic target in bladder cancer. The expression of CCAT2 can be quantitatively controlled by the synthetic “tetracycline-on” switch system in bladder cancer in response to different concentrations of doxycycline to inhibit the development of bladder cancer cells.

Synthetic tetracycline-controllable shRNA targeting long non-coding RNA HOXD-AS1 inhibits the progression of bladder cancer

BackgroundLong non-coding RNAs (lncRNAs) have been proved to act as key molecules in cancer development and progression. Dysregulation of lncRNAs is discovered in various tumor tissues and cancer cells where they can serve as oncogenes or tumor suppressors. Long non-coding RNA HOXD-AS (HOXD cluster antisense RNA 1) has recently been identified to be involved in the development of several cancers including neuroblastoma, adenocarcinomas and breast cancer. However, the role of HOXD-AS1 in bladder cancer remains unknown.MethodsThe synthetic tetracycline-controllable shRNA was used to modulate the level of HOXD-AS1 by adding different concentrations of doxycycline (dox). RT-qPCR was used to detect the expression level of HOXD-AS1. Cell proliferation was determined by CCK-8 assay and EdU incorporation experiment when HOXD-AS1 was knocked down. We used wound-healing assay for detecting the effect of HOXD-AS1 on cell migration. Eventually, cell apoptosis was determined by caspase 3 ELISA assay and flow cytometry assay.ResultsIn this study, we found that the expression level of HOXD-AS1 was significantly increased in bladder cancer tissues and cells. Furthermore, high expression of HOXD-AS1 was significantly related to tumor size, histological grade and TNM stage. In vitro assays confirmed that knockdown of HOXD-AS1 suppressed cell proliferation/migration and increased the rate of apoptotic cell in bladder cancer cells. At last, we used the important element of synthetic biology, tetracycline(tet)-controllable switch, to construct tet-controllable shRNA vectors which can modulate the expression of HOXD-AS1 in a dosage-dependent manner.ConclusionsOur research suggested that high expression of HOXD-AS1 may be involved in the bladder cancer carcinogenesis through inhibiting the phenotypes and activating endogenous cancer-related molecular pathways. Therefore, HOXD-AS1 may act as an oncogene and provide a potential attractive therapeutic target for bladder cancer. In addition, the synthetic tetracycline-controllable shRNA may provide a novel method for cancer research in vitro assays.

A dominant-negative mutation of HSF2 associated with idiopathic azoospermia

Idiopathic azoospermia (IA) is a severe form of male infertility due to unknown causes. The HSF2 gene, encoding the heat shock transcription factor 2, had been suggested to play a significant role in the spermatogenesis process since the Hsf2-knockout male mice showed spermatogenesis defects. To examine whether HSF2 is involved in the pathogenesis of IA in human, we sequenced all the exons of HSF2 in 766 patients diagnosed with IA and 521 proven fertile men. A number of coding mutations private to the patient group, which include three synonymous mutations and five missense mutations, were identified. Of the missense mutations, our functional assay demonstrated that one heterozygous mutation, R502H, caused a complete loss of HSF2 function and that the mutant suppressed the normal function of the wild-type (WT) allele through a dominant-negative effect, thus leading to the dominant penetrance of the mutant allele. These results support a role for HSF2 in the pathogenesis of IA and further implicate this transcription factor as a potential therapeutic target.

Long noncoding RNA HOTAIR promotes metastasis of renal cell carcinoma by up-regulating histone H3K27 demethylase JMJD3

Long Noncoding RNAs (lncRNAs) are a kind of non-protein coding transcripts longer than 200 nucleotides, and play important roles in diverse biological processes, such as embryonic development and apoptosis. Homeobox (HOX) transcript antisense intergenic RNA (HOTAIR) is a negative prognostic factor in a variety of human cancers, such as breast, liver and lung cancers. HOTAIR can promote cancer cell metastasis by reprogramming chromatin organization. In the present study, HOTAIR expression was elevated in tissues of renal cell carcinoma compared to adjacent normal tissues, and positively correlated with metastasis (P<0.05). The cell migration was inhibited in scratch test and transwell assay after HOTAIR knockdown (P<0.05). Further researches revealed that histone demethylase JMJD3 was reduced and its target gene Snai1 expression was down-regulated after HOTAIR suppression (P<0.05). Meanwhile, the level of histone methytransferase EZH2 target gene PCDHB5 was increased (P<0.05). Collectively, these data suggest that HOTAIR is an important promoter in metastasis of renal cell carcinoma and also plays a dual regulatory role in chromatin state by effecting both histone metylation and demethylation at different gene loci.

Up-regulation of long non-coding RNA PANDAR is associated with poor prognosis and promotes tumorigenesis in bladder cancer.

BackgroundLong non-coding RNAs (lncRNAs) have emerged as biomarkers and important regulators of tumor development and progression. PANDAR (promoter of CDKN1A antisense DNA damage activated RNA) is a novel long non-coding RNA that acts as a potential biomarker and involves in development of multiple cancers. However, the clinical significance and molecular mechanism of PANDAR in bladder cancer is still unknown. In this study, we aimed to figure out the role of PANDAR in bladder cancer.MethodsThe relative expression level of lncRNA PANDAR was determined by Real-Time qPCR in a total of 55 patients with urothelial bladder cancer and in different bladder cancer cell lines. We inhibited PANDAR expression by transfecting PANDAR specific siRNA and enhanced PANDAR expression by transfecting a PANDAR expression vector (pcDNA3.1-PANDAR). Cell proliferation was determined by using both CCK-8 assay and Edu assay. Cell apoptosis was determined by using ELISA assay, Hoechst 33342 staining and Flow cytometry. Cell migration was determined by using transwell assay. All experimental data from three independent experiments were analyzed by χ2 test or Student’s t-test and results were expressed as mean ± standard deviation.ResultsWe found that PANDAR was significantly up-regulated in bladder cancer tissues compared with paired-adjacent nontumorous tissues in a cohort of 55 bladder cancer patients. Moreover, increased PANDAR expression was positively correlated with higher histological grade (P < 0.05) and advanced TNM stage (P < 0.05). Further experiments demonstrated that inhibited cell proliferation/migration and induced apoptosis by silencing PANDAR were also observed in bladder cancer cells. Furthermore, over expression of PANDAR in bladder cancer cells promoted the proliferation/migration and suppressed apoptosis.ConclusionsThese findings demonstrate that PANDAR plays oncogenic roles in bladder cancer and PANDAR may serve as a potential prognostic biomarker and therapeutic target of bladder cancer.

Over-expression of long noncoding RNA BANCR inhibits malignant phenotypes of human bladder cancer

BackgroundAccumulating evidences indicated that lncRNAs play crucial regulatory roles in oncogenesis and progression of cancers. BRAF activated non-coding RNA (BANCR) has been identified to contribute to the progression of some human cancers. However, the relationship between BANCR and bladder cancer (BC) is largely unclear.MethodsBANCR expression levels in BC, paired non-cancer tissues and BC cell lines were detected by real-time quantitative RT-PCR (qRT-PCR). The relationships between BANCR expression levels and the clinical characteristics were evaluated. BANCR expression was enhanced by transfecting a pcDNA-BANCR vector. We used both CCK-8 assay and Edu assay to detect cell proliferation. We also detect cell apoptosis and migration by using ELISA assay, Flow cytometry and transwell assay, respectively. All statistical analyses were executed by using the SPSS 20.0 software.ResultsBANCR expression levels were remarkably decreased in BC tissues compared with adjacent noncancerous tissues. BANCR expression levels in two BC cell lines were also significantly down-regulated. Clinicopathologic analysis revealed that low BANCR expression was positively correlated with TNM stage, but not associated with other clinicopathological characteristics. BANCR has been successfully overexpressed in BC cell lines (T24 and SW780) by transfecting a pcDNA-BANCR vector. Cell proliferation inhibition, apoptosis induction and migration suppression were also observed in pCDNA-BANCR-transfected T24 and SW780 cells.ConclusionsThese data suggested that BANCR represents a tumor suppressor player in bladder cancer, contributes to tumor proliferation, apoptosis and migration, and may serve as a new candidate biomarker and a potential therapeutic target for patients with BC.

Inducing cell growth arrest and apoptosis by silencing long non-coding RNA PCAT-1 in human bladder cancer.

Long non-coding RNAs (lncRNAs) are a class of non-coding RNAs that play important roles in cancer development and progression. Prostate cancer-associated transcript 1 (PCAT-1) is a novel lncRNA that promotes cell proliferation in prostate cancer. We hypothesized that PCAT-1 also have roles in bladder cancer. In this study, we found that PCAT-1 was up-regulated in bladder cancer compared to paired normal urothelium. Cell proliferation inhibition and apoptosis induction were also observed in PCAT-1 small hairpin RNA (shRNA)-transfected bladder cancer T24 and 5637 cells. Our data suggest that PCAT-1 plays oncogenic roles and can be used as a therapeutic target for treating human bladder cancer.

Identification of Ube2b as a Novel Target of Androgen Receptor in Mouse Sertoli Cells

ABSTRACT Many genes are regulated by androgen and its receptor (AR), but the direct target genes of AR, especially those involved in spermatogenesis and male infertility, remain unclear. Here, we identified ubiquitin-conjugating enzyme E2B (Ube2b) as a critical target gene of AR. The expression of UBE2B was decreased in the testes of Sertoli cell AR knockout (S-AR−/y) mice analyzed by quantitative RT-PCR (qRT-PCR) and immunofluorescence. The upregulation of Ube2b gene by testosterone was further demonstrated by Western blot and qRT-PCR in TM4 cells, a mouse Sertoli cell line. Moreover, luciferase assay, electrophoretic mobility shift assay, and chromatin immunoprecipitation assay validated that the ligand-bound AR activated Ube2b transcription via direct binding to the androgen-responsive element of the Ube2b promoter. In vitro analyses showed that testosterone increased UBE2B expression and activated H2A ubiquitylation, while downregulation of UBE2B blocked the testosterone-induced H2A ubiquitylation. The ubiquitylation of H2A was markedly decreased in the testes of S-AR−/y mice by immunohistochemistry. Digital gene expression analysis showed that 113 genes were significantly downregulated and 71 were upregulated by UBE2B in TM4 cells. These results suggest that Ube2b, as a direct AR transcriptional target in Sertoli cells, mediates the function of AR in spermatogenesis by promoting H2A ubiquitylation.

LncRNA MALAT1 Inhibits Apoptosis and Promotes Invasion by Antagonizing miR-125b in Bladder Cancer Cells

Accumulating evidences suggest that longnon-coding RNAs (lncRNAs) play functional roles in development of different cancers, including cancer initiation and progression. Metastasis associated lung adenocarcinoma transcript 1(MALAT1) is a well-known lncRNA which was previously shown to be a direct target of miR-125b in bladder cancer (BCa) and to promote cancer progression and invasion. However, little is known whether MALAT1 can also target miR-125b. In the present study, using CRISPR-based technologies and qRT-PCR, we show that MALAT1 is capable of suppressing mature miR-125b and increasing the expression of its target genes (Bcl-2 and MMP-13), but has no effect on pri-miR-125b and pre-miR-125b. We observe that the biotin-labeled MALAT1-RNA probe is able to pull down Ago2 and miR-125b and that the negative regulation of miR-125b by MALAT1 is dependent on Ago2. Importantly, the results of flow cytometry assay and transwell assay reveal that the MALAT1-mediated cancer progression is in part due to specific suppression of miR-125b and activation of its two target genes. All together, these data suggest that the “MALAT1-miR-125b-Bcl-2 / MMP-13” axis plays an important role in the progression of BCa, thereby may provide a potential therapeutic strategy for the treatment of human BCa.

Whole-Genome Synthesis and Characterization of Viable S13-Like Bacteriophages

Background Unprecedented progresses in high-throughput DNA sequencing and de novo gene synthesis technologies have allowed us to create living organisms in the absence of natural template. Methodology/Principal Findings The sequence of wild-type S13 phage genome was downloaded from GenBank. Two synonymous mutations were introduced into wt-S13 genome to generate m1-S13 genome. Another mutant, m2-S13 genome, was obtained by engineering two nonsynonymous mutations in the capsid protein coding region of wt-S13 genome. A chimeric phage genome was designed by replacing the F capsid protein open reading frame (ORF) from phage S13 with the F capsid protein ORF from phage G4. The whole genomes of all four phages were assembled from a series of chemically synthesized short overlapping oligonucleotides. The linear synthesized genomes were circularized and electroporated into E.coli C, the standard laboratory host of S13 phage. All four phages were recovered and plaques were visualized. The results of sequencing showed the accuracy of these synthetic genomes. The synthetic phages were capable of lysing their bacterial host and tolerating general environmental conditions. While no phenotypic differences among the variant strains were observed when grown in LB medium with CaCl2, the S13/G4 chimera was found to be much more sensitive to the absence of calcium and to have a lower adsorption rate under calcium free condition. Conclusions/Significance The bacteriophage S13 and its variants can be chemically synthesized. The major capsid gene of phage G4 is functional in the phage S13 life cycle. These results support an evolutional hypothesis which has been proposed that a homologous recombination event involving gene F of quite divergent ancestral lineages should be included in the history of the microvirid family.