scholarly journals Identification of mitochondrial RNA polymerase as a potential therapeutic target of osteosarcoma

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Qi-cai Han ◽  
Xiang-yang Zhang ◽  
Peng-hui Yan ◽  
Song-feng Chen ◽  
Fei-fei Liu ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Therapeutic Target ◽  
Cell Activity ◽  
Chain Complex ◽  
Intratumoral Injection ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion ◽  
Mitochondrial Rna

AbstractPOLRMT (RNA polymerase mitochondrial) is essential for transcription of mitochondrial genome encoding components of oxidative phosphorylation process. The current study tested POLRMT expression and its potential function in osteosarcoma (OS). The Cancer Genome Atlas (TCGA) cohorts and Gene Expression Profiling Interactive Analysis (GEPIA) database both show that POLRMT transcripts are elevated in OS tissues. In addition, POLRMT mRNA and protein levels were upregulated in local OS tissues as well as in established and primary human OS cells. In different OS cells, shRNA-induced stable knockdown of POLRMT decreased cell viability, proliferation, migration, and invasion, whiling inducing apoptosis activation. CRISPR/Cas9-induced POLRMT knockout induced potent anti-OS cell activity as well. Conversely, in primary OS cells ectopic POLRMT overexpression accelerated cell proliferation and migration. In vivo, intratumoral injection of adeno-associated virus-packed POLRMT shRNA potently inhibited U2OS xenograft growth in nude mice. Importantly, levels of mitochondrial DNA, mitochondrial transcripts and expression of respiratory chain complex subunits were significantly decreased in U2OS xenografts with POLRMT shRNA virus injection. Together, POLRMT is overexpressed in human OS, promoting cell growth in vitro and in vivo. POLRMT could be a novel therapeutic target for OS.

scholarly journals HDAC4 promotes nasopharyngeal carcinoma progression and serves as a therapeutic target

2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Chun Cheng ◽  
Jun Yang ◽  
Si-Wei Li ◽  
Guofu Huang ◽  
Chenxi Li ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Tumor Growth ◽  
Therapeutic Target ◽  
Histone Deacetylases ◽  
Migration And Invasion ◽  
Poor Overall Survival ◽  
Mesenchymal Transition ◽  
E Cadherin

AbstractHistone deacetylases (HDACs) are involved in tumor progression, and some have been successfully targeted for cancer therapy. The expression of histone deacetylase 4 (HDAC4), a class IIa HDAC, was upregulated in our previous microarray screen. However, the role of HDAC4 dysregulation and mechanisms underlying tumor growth and metastasis in nasopharyngeal carcinoma (NPC) remain elusive. Here, we first confirmed that the HDAC4 levels in primary and metastatic NPC tissues were significantly increased compared with those in normal nasopharyngeal epithelial tissues and found that high HDAC4 expression predicted a poor overall survival (OS) and progression-free survival (PFS). Functionally, HDAC4 accelerated cell cycle G1/S transition and induced the epithelial-to-mesenchymal transition to promote NPC cell proliferation, migration, and invasion in vitro, as well as tumor growth and lung metastasis in vivo. Intriguingly, knockdown of N-CoR abolished the effects of HDAC4 on the invasion and migration abilities of NPC cells. Mechanistically, HDAC3/4 binds to the E-cadherin promoter to repress E-cadherin transcription. We also showed that the HDAC4 inhibitor tasquinimod suppresses tumor growth in NPC. Thus, HDAC4 may be a potential diagnostic marker and therapeutic target in patients with NPC.

scholarly journals Potential Role of microRNA-183 as a Tumor Suppressor in Hepatocellular Carcinoma

2018 ◽  
Vol 51 (5) ◽  
pp. 2065-2072 ◽  
Author(s):  
Wei Bian ◽  
Hongfei Zhang ◽  
Miao Tang ◽  
Shaojun Zhang ◽  
Lichao Wang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Hepg2 Cells ◽  
Molecular Mechanisms ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion ◽  
Metastatic Progression ◽  
Mesenchymal Transition ◽  
Reporter Assays

Background/Aims: Disseminated tumors, known as metastases, are responsible for ninety-percent of mortality due to cancer. Epithelial to mesenchymal transition, a phenomenon required for morphological conversion of non-motile discoid shaped epithelial cells to highly motile spindle-shaped mesenchymal cells, is thought to be a pre-requisite for metastatic progression. Metastasis-associated 1 (MTA1) protein is a prime inducer of EMT and metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the molecular mechanisms that regulate the expression and function of MTA1 in HCC have not been elucidated. Methods: In silico prediction algorithms were used to find microRNAs (miRNAs) that may target MTA1. We examined the relationship between the expression of MTA1 and miR-183 using quantitative real time PCR. We also determined the levels of the MTA1 protein using immunohistochemistry. Reporter assays, in the presence and absence of the miR-183 mimic, were used to confirm MTA1 as a bona fide target of miR183. The effect of miR-183 on HCC pathogenesis was determined using a combination of in vitro migration and invasion assay, together with in vivo xenograft experiments. The correlation between miR-183 and MTA1 expression was also studied in samples from HCC patients, and in The Cancer Genome Atlas dataset. Results: Analysis of the sequence database revealed that MTA1 is a putative target of miR-183. MTA1 protein and RNA expression showed opposite trends to miR-183 expression in breast, renal, prostate, and testicular tissue samples from cancer patients, and in the metastatic HCC cell line HepG2. An inverse correlation was also observed between MTA1 (high) and miR-183 (low) expression within samples from HHC patients and in the TCGA dataset. Reporter assays in HepG2 cells showed that miR-183 could inhibit translation of a reporter harboring the wild-type, but not the mutant miR-183 3’-untranslated region (UTR). In addition, miR-183 significantly inhibited in vitro migration and invasion in HepG2 cells, and in vivo hepatic metastasis. Conclusion: Our results reveal a novel post-transcriptional regulatory mechanism for MTA1 expression via miR-183, which is suppressed during HCC pathogenesis.

scholarly journals Primary Cilia Blockage Promotes the Malignant Behaviors of Hepatocellular Carcinoma via Induction of Autophagy

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Lian Liu ◽  
Jia-Qi Sheng ◽  
Mu-Ru Wang ◽  
Yun Gan ◽  
Xiao-Li Wu ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Primary Cilia ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion ◽  
Serum Starvation ◽  
Autophagic Flux ◽  
And Function ◽  
Hcc Cells

Primary cilia are organelles protruding from cell surface into environment that function in regulating cell cycle and modulating cilia-related signal. Primary ciliogenesis and autophagy play important roles in tumorigenesis. However, the functions and interactions between primary cilia and autophagy in hepatocellular carcinoma (HCC) have not been reported yet. Here, we aimed to investigate the relationship and function of primary cilia and autophagy in HCC. In vitro, we showed that serum starvation stimuli could trigger primary ciliogenesis in HCC cells. Blockage of primary ciliogenesis by IFT88 silencing enhanced the proliferation, migration, and invasion ability of HCC cells. In addition, inhibition of primary cilia could positively regulate autophagy. However, the proliferation, migration, and invasion ability which were promoted by IFT88 silencing could be partly reversed by inhibition of autophagy. In vivo, interference of primary cilia led to acceleration of tumor growth and increase of autophagic flux in xenograft HCC mouse models. Moreover, IFT88 high expression or ATG7 low expression in HCC tissues was correlated with longer survival time indicated by the Cancer Genome Atlas (TCGA) analysis. In conclusion, our study demonstrated that blockage of primary ciliogenesis by IFT88 silencing had protumor effects through induction of autophagy in HCC. These findings define a newly recognized role of primary cilia and autophagy in HCC.

scholarly journals TRIM33 Overexpression Inhibits the Progression of Clear Cell Renal Cell Carcinoma In Vivo and In Vitro

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Yingkun Xu ◽  
Guangzhen Wu ◽  
Jiayao Zhang ◽  
Jianyi Li ◽  
Ningke Ruan ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Mrna Expression ◽  
Wnt Signaling Pathway ◽  
Xenograft Model ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion ◽  
Cell Renal Cell Carcinoma ◽  
Expression Levels

Purpose. To evaluate the expression of tripartite motif-containing 33 (TRIM33) in ccRCC tissues and explore the biological effect of TRIM33 on the progress of ccRCC. Method. The Cancer Genome Atlas (TCGA) database was used to examine the mRNA expression levels of TRIM33 in ccRCC tissues and its clinical relevance. Immunohistochemistry (IHC) was performed to evaluate its expression in ccRCC tissues obtained from our hospital. The correlation between TRIM33 expression and clinicopathological features of the patients was also investigated. The effects of TRIM33 on the proliferation of ccRCC cells were examined using the CCK-8 and colony formation assays. The effects of TRIM33 on the migration and invasion of ccRCC cells were explored through wound healing and transwell assays, along with the use of Wnt signaling pathway agonists in rescue experiments. Western blotting was used to explore the potential mechanism of TRIM33 in renal cancer cells. A xenograft model was used to explore the effect of TRIM33 on tumor growth. Result. Bioinformatics analysis showed that TRIM33 mRNA expression in ccRCC tissues was downregulated, and low TRIM33 expression was related to poor prognosis in ccRCC patients. In agreement with this, low TRIM33 expression was detected in human ccRCC tissues. TRIM33 expression levels were correlated with clinical characteristics, including tumor size and Furman’s grade. Furthermore, TRIM33 overexpression inhibited proliferation, migration, and invasion of 786-O and ACHN cell lines. The rescue experiment showed that the originally inhibited migration and invasion capabilities were restored. TRIM33 overexpression reduced the expression levels of β-catenin, cyclin D1, and c-myc, and inhibited tumor growth in ccRCC cells in vivo. Conclusion. TRIM33 exhibits an abnormally low expression in human ccRCC tissues. TRIM33 may serve as a potential therapeutic target and prognostic marker for ccRCC.

scholarly journals Loss of COPZ1 induces NCOA4 mediated autophagy and ferroptosis in glioblastoma cell lines

Oncogene ◽  
2021 ◽  
Author(s):  
Yulin Zhang ◽  
Yang Kong ◽  
Yuan Ma ◽  
Shilei Ni ◽  
Tobias Wikerholmen ◽  
...  
Keyword(s):  
Iron Metabolism ◽  
Survival Data ◽  
Therapeutic Target ◽  
Tumor Grade ◽  
The Cancer Genome Atlas ◽  
Subsequent Increase ◽  
Tissue Samples ◽  
Protein Levels

AbstractDysregulated iron metabolism is a hallmark of many cancers, including glioblastoma (GBM). However, its role in tumor progression remains unclear. Herein, we identified coatomer protein complex subunit zeta 1 (COPZ1) as a therapeutic target candidate which significantly dysregulated iron metabolism in GBM cells. Overexpression of COPZ1 was associated with increasing tumor grade and poor prognosis in glioma patients based on analysis of expression data from the publicly available database The Cancer Genome Atlas (P < 0.001). Protein levels of COPZ1 were significantly increased in GBM compared to non-neoplastic brain tissue samples in immunohistochemistry and western blot analysis. SiRNA knockdown of COPZ1 suppressed proliferation of U87MG, U251 and P3#GBM in vitro. Stable expression of a COPZ1 shRNA construct in U87MG inhibited tumor growth in vivo by ~60% relative to controls at day 21 after implantation (P < 0.001). Kaplan–Meier analysis of the survival data demonstrated that the overall survival of tumor bearing animals increased from 20.8 days (control) to 27.8 days (knockdown, P < 0.05). COPZ1 knockdown also led to the increase in nuclear receptor coactivator 4 (NCOA4), resulting in the degradation of ferritin, and a subsequent increase in the intracellular levels of ferrous iron and ultimately ferroptosis. These data demonstrate that COPZ1 is a critical mediator in iron metabolism. The COPZ1/NCOA4/FTH1 axis is therefore a novel therapeutic target for the treatment of human GBM.

scholarly journals miR-186-5p Prevents Hepatocellular Carcinoma Progression Through Targeting METTL3 to Regulate m6A-Mediated Stabilization of FSTL5

2021 ◽  
Author(s):  
DengYong Zhang ◽  
FangFang Chen ◽  
ShuoShuo Ma ◽  
YongChun Zhou ◽  
Wanliang Sun ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Rna Stability ◽  
The Cancer Genome Atlas ◽  
Cell Counting ◽  
Migration And Invasion ◽  
Dependent Manner ◽  
Report Analysis ◽  
Hcc Cells

Abstract Background: Hepatocellular carcinoma (HCC) processes in multi-steps which involves the sophisticated interactions of genetics, epigenetics, and transcriptional changes. According to before investigations, methyltransferase-like 3 (METTL3)-mediated m6A modification regulates the development of various cancers by regulating gene stability. However, the studies focusing on miRNA’s regulatory effect of N6-methyladenosine (m6A) modification on HCC progression are still limited. Methods: Immunochemistry (IHC) staining detected the histopathological changes in the tumor tissues. Cell Counting Kit-8 (CCK-8), clone formation, and transwell assay investigated the changes in cancer cell proliferation, invasion, and migration. The RNA m6A level was confirmed by methylated RNA immunoprecipitation. The RNA stability assay indicated the half-life (t1/2) of RNA in HCC cells. The prognosis of the indicated patients’ cohort was analyzed using the cancer genome atlas (TCGA) datasets. Luciferase report analysis was used to study the potential binding between microRNA (miRNA) and mRNA. A mice tumor transplant model was further established to study the changes in tumor progression. Results: Follistatin-like 5 (FSTL5) was found to be significantly downregulated in HCC, and it inhibited the further progression of HCC. The RNA stability analysis indicated that the mRNA t1/2 gene of HCC cells was shortened. Besides, METTL3 reduced the stability of FSTL5 mRNA in a m6A-YTH domain family 2(YTHDF2)-dependent manner. Functional experiments revealed that the downregulated METTL3 inhibited the HCC progression by up-regulating FSTL5 in vitro and in vivo. Luciferase report analysis confirmed that miR-186-5p directly targeted the METTL3. Additionally, miR-186-5p inhibited the proliferation, migration, and invasion of HCC cells by downregulating METTL3. We identified that miR-186-5p prevented the HCC progression by targeting METTL3 to regulate m6A-mediated FSTL5 stabilization. Conclusions: The miR-186-5p/METTL3/YTHDF2/FSTL5 axis perhaps point out a new direction for the targeted therapy of HCC.

Accurate in vitro transcription of Xenopus laevis mitochondrial DNA from two bidirectional promoters

1986 ◽  
Vol 6 (7) ◽  
pp. 2543-2550
Author(s):  
D F Bogenhagen ◽  
B K Yoza
Keyword(s):  
Mitochondrial Dna ◽  
Xenopus Laevis ◽  
Rna Polymerase ◽  
Consensus Sequence ◽  
In Vitro Transcription ◽  
Xenopus Laevis Oocytes ◽  
Mitochondrial Rna ◽  
Bidirectional Promoters

The mitochondrial RNA polymerase from Xenopus laevis oocytes was partially purified by heparin-Sepharose chromatography and phosphocellulose chromatography. This RNA polymerase preparation specifically initiated the transcription of X. laevis mitochondrial DNA (mtDNA) from two bidirectional promoters contained within a 123-base-pair segment of the mtDNA between the heavy-strand replication origin and the rRNA cistrons. Transcription in vitro initiated from precisely the same start sites previously mapped as initiation sites for transcription in vivo. At each of the four sites, initiation occurred within a conserved nucleotide sequence, ACPuTTATA. This consensus sequence is not related to promoters for transcription of human mtDNA.

scholarly journals Characterization of novel neutralizing mouse monoclonal antibody JM1-24-3 developed against MUC18 in metastatic melanoma

2020 ◽  
Vol 39 (1) ◽  
Author(s):  
Runhua Feng ◽  
Yuling Wang ◽  
Vijaya Ramachandran ◽  
Qinhong Ma ◽  
Matthew M. May ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Metastatic Melanoma ◽  
Therapeutic Target ◽  
High Throughput Screening ◽  
Conformational Epitope ◽  
Migration And Invasion ◽  
Melanoma Tumor ◽  
Downstream Signaling

Abstract Background MUC18 is a glycoprotein highly expressed on the surface of melanoma and other cancers which promotes tumor progression and metastasis. However, its mechanism of action and suitability as a therapeutic target are unknown. Methods A monoclonal antibody (mAb) (JM1-24-3) was generated from metastatic melanoma tumor live cell immunization, and high-throughput screening identified MUC18 as the target. Results Analysis of molecular interactions between MUC18 and JM1-24-3 revealed that the downstream signaling events depended on binding of the mAb to a conformational epitope on the extracellular domain of MUC18. JM1-24-3 inhibited melanoma cell proliferation, migration and invasion in vitro and reduced tumor growth and metastasis in vivo. Conclusion These results confirm that MUC18 is mechanistically important in melanoma growth and metastasis, suggest that the MUC18 epitope identified is a promising therapeutic target, and that the JM1-24-3 mAb may serve as the basis for a potential therapeutic agent.

scholarly journals Upregulation of CENPM promotes hepatocarcinogenesis through mutiple mechanisms

2019 ◽  
Vol 38 (1) ◽  
Author(s):  
Yusha Xiao ◽  
Rahmathullah Mohamed Najeeb ◽  
Dong Ma ◽  
Kang Yang ◽  
Qiu Zhong ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle ◽  
Hepatoma Cell ◽  
Single Gene ◽  
Gene Set Enrichment Analysis ◽  
Negative Regulator ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion

Abstract Background Hepatocellular carcinoma (HCC) still remains a dominating medical challenge in early diagnosis and clinical therapy. Centromere protein M (CENPM) has been proved to be over-expressed in HCC tissues, but carcinogenic mechanism of CENPM contributing to liver cancer is poorly understood. Methods In this study, we first explored mRNA and protein levels of CENPM in HCC samples, matching adjacent non-tumor tissues and six hepatoma cell lines by polymerase chain reaction (PCR), western blotting and immunohistochemistry (IHC). Clinical data of HCC patients downloaded from The Cancer Genome Atlas (TCGA) were also analyzed. The character of CENPM concerned with HCC progression through several functional experimentations in vitro and in vivo was researched. Bioinformatics was carried out to further discover biological functions of CENPM. Results CENPM was positively up-regulated in HCC and connected with a poor prognosis. Silencing CENPM repressed cell proliferation in vivo and in vitro, and knock-down CENPM inhibited cell migration and invasion. Additionally, depletion of CENPM can promote cell apoptosis and arrested cell cycle. Furthermore, single-gene gene set enrichment analysis (GSEA) analysis indicated that CENPM was linked to the P53 signaling pathway and cell cycle pathway, and our research supported this prediction. Finally, we also found that miR-1270 was a negative regulator and participated in post-transcriptional regulation of CENPM, and hepatitis B virus X protein (HBx) can promote hepatocellular carcinoma by suppressing miR1270. Conclusion CENPM was closely associated with HCC progression and it could be considered as a new possible biomarker along with a therapeutic target for HCC.

scholarly journals Anti-viral nucleotide incorporation by recombinant human mitochondrial RNA polymerase is predictive for increased in vivo mitochondrial toxicity risk

2016 ◽  
pp. AAC.01253-16 ◽  
Author(s):  
Martijn Fenaux ◽  
Xiaodong Lin ◽  
Fumiaki Yokokawa ◽  
Zachary Sweeney ◽  
Oliver Saunders ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Mitochondrial Dysfunction ◽  
Elevated Serum ◽  
Nucleoside Analogs ◽  
Hepatic Function ◽  
Gene Signature ◽  
Mitochondrial Rna ◽  
Mitochondrial Rna Polymerase

Nucleoside or nucleotide inhibitors are a highly successful class of antivirals due to selectivity, potency, broad coverage, and high barrier to resistance. Nucleosides are the backbone of combination treatments for HIV, hepatitis B and - since the FDA approval of sofosbuvir in 2013 - also for hepatitis C (HCV). However, many promising nucleotides have advanced to clinical trials only to be terminated due to unexpected toxicity. Here we describe the in vitro pharmacology of1, a monophosphate prodrug of a 2’ -ethynyluridine developed for the treatment of HCV.1inhibits multiple HCV genotypes in vitro (EC50= 0.05-0.1 μM) with a selectivity index of >300 (CC50= 30 μM in MT-4 cells). The active triphosphate metabolite of1,2, does not inhibit human α, β or γ DNA polymerases, but was a substrate for incorporation by the human mitochondrial RNA polymerase (POLRMT). In dog, the oral administration of1resulted in elevated serum liver enzymes and microscopic changes in the liver. Transmission electron microscopy showed significant mitochondrial swelling and lipid accumulation in hepatocytes. Gene expression analysis revealed dose-proportional gene signature changes linked to loss of hepatic function and increased mitochondrial dysfunction. The potential of in vivo toxicity through mitochondrial polymerase incorporation by nucleoside analogs has been previously shown. This study shows that even moderate levels of nucleotide analog incorporation by POLRMT increase the risk of in vivo mitochondrial dysfunction. Based on these results, further development of1as an anti-HCV compound was terminated.

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