Suppression of DPYD expression in RKO Cells via DNA methylation in the regulatory region of the DPYD promoter: a potentially important epigenetic mechanism regulating DPYD expression

2007 ◽  
Vol 85 (3) ◽  
pp. 337-346 ◽  
Author(s):  
Xue Zhang ◽  
Richie Soong ◽  
Kangsheng Wang ◽  
Lin Li ◽  
James R. Davie ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Trichostatin A ◽  
Dihydropyrimidine Dehydrogenase ◽  
Mrna Level ◽  
Regulatory Region ◽  
Cancer Cell Line ◽  
Epigenetic Mechanism ◽  
Colorectal Cancer Cell Line ◽  
Transcriptional Level

Dihydropyrimidine dehydrogenase (DPD) is one of the factors that determine the efficacy and toxicity of 5-fluorouracil. Variations in DPD activity may result from alterations at the transcriptional level of the DPYD gene. Heterogeneity in DPYD expression has been reported, but the molecular mechanisms responsible for this remain unclear. We investigated methylation of the DPYD promoter as a mechanism for transcriptional regulation of DPYD in the RKO colorectal cancer cell line. We demonstrate that the active transcription machinery for DPYD is present in RKO cells, but promoter binding of Sp1, a transactivator of DPYD, was inhibited, which on subsequent examination was shown to be associated with dense promoter methylation. Treatment with 5-aza-2′-deoxycytidine alone or the combination of 5-aza-2′-deoxycytidine and trichostatin A induced demethylation of the promoter and markedly increased the DPYD mRNA level in RKO cells but not in unmethylated WiDr cells. Furthermore, in vitro methylation of the DPYD promoter decreased promoter activity. These data suggest an important role for methylation in DPYD suppression. The transcriptional suppression of DPYD by methylation may be responsible for the increased 5-fluorouracil sensitivity observed in some patients. This may also provide insight into the mechanism underlying the downregulation of DPYD in some colorectal cancers.

Synthesis, Cytotoxicity and Antioxidant Activity of New Analogs of RC-121 Synthetic Derivatives of Somatostatin

2019 ◽  
Vol 18 (10) ◽  
pp. 1417-1424 ◽  
Author(s):  
Emilia Naydenova ◽  
Diana Wesselinova ◽  
Svetlana Staykova ◽  
Ivan Goshev ◽  
Ljubomir Vezenkov
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Cell Line ◽  
Cancer Cell ◽  
Cancer Cell Line ◽  
Colorectal Cancer Cell Line ◽  
Cervical Cancer Cell Line ◽  
Synthetic Derivatives ◽  
Derivatives Of

Background: Based on the structure of RC-121 (D-Phe-c (Cys-Tyr-D-Trp-Lys-Val-Cys)-Thr-NH2, - synthetic derivatives of somatostatin), some analogs were synthesized and tested for in vitro cytotoxic and antioxidant activity. Objectives: The new analogs were modifyed at position 5 with Dap (diaminopropanoic acid), Dab (diaminobutanoic acid) and Orn and at position 6 with the unnatural amino acids Tle (t-leucine). Methods: The in vitro cytotoxic effects of the substances were investigated against a panel of human tumor cell lines HT-29 (Human Colorectal Cancer Cell Line), MDA-MB-23 (Human Breast Cancer Cell Line), Hep G-2 (Human Hepatocellular Carcinoma Cell Line) and HeLa (cervical cancer cell line). The antioxidant capacities were tested by ORAC (Oxygen Radical Antioxidant Capacity) and HORAC (Hydroxyl Radical Averting Capacity) methods. Results: All substances expressed significantly higher antioxidant capacity by comparison with galic acid and Trolox. All substances showed considerable antioxidant capacity as well. Compound 2T (D-Phe-c(Cys-Tyr-DTrp- Dap-Tle-Cys)-Thr-NH2)had the highest antioxidant effect. The compound 4T (D-Phe-c(Cys-Tyr-D-Trp- Orn-Tle-Cys)-Thr-NH2) displayed antiproliferative effect on HeLa cells with IC50 30 µM. The peptide analog 3T (D-Phe-c(Cys-Tyr-D-Trp-Lys-Tle-Cys)-Thr-NH2) exerted the most pronounced inhibition on the cell vitality up to 53%, 56% and 65% resp. against MDA-MB-23, Hep G-2, HeLa in the higher tested concentration. Conclusion: The somatostatin analogs showed moderate influence on the vitality of different tumor cells and could be used in changing their pathology.

scholarly journals Analysis of a Preliminary microRNA Expression Signature in a Human Telangiectatic Osteogenic Sarcoma Cancer Cell Line

2021 ◽  
Vol 22 (3) ◽  
pp. 1163
Author(s):  
Gaia Palmini ◽  
Cecilia Romagnoli ◽  
Simone Donati ◽  
Roberto Zonefrati ◽  
Gianna Galli ◽  
...  
Keyword(s):  
Cell Line ◽  
Molecular Mechanisms ◽  
Osteogenic Sarcoma ◽  
Cancer Cell Line ◽  
Microscopic Features ◽  
In Vitro Establishment ◽  
Profile Characteristic ◽  
First Time

Telangiectatic osteosarcoma (TOS) is an aggressive variant of osteosarcoma (OS) with distinctive radiographic, gross, microscopic features, and prognostic implications. Despite several studies on OS, we are still far from understanding the molecular mechanisms of TOS. In recent years, many studies have demonstrated not only that microRNAs (miRNAs) are involved in OS tumorigenesis, development, and metastasis, but also that the presence in high-grade types of OS of cancer stem cells (CSCs) plays an important role in tumor progression. Despite these findings, nothing has been described previously about the expression of miRNAs and the presence of CSCs in human TOS. Therefore, we have isolated/characterized a putative CSC cell line from human TOS (TOS-CSCs) and evaluated the expression levels of several miRNAs in TOS-CSCs using real-time quantitative assays. We show, for the first time, the existence of CSCs in human TOS, highlighting the in vitro establishment of this unique stabilized cell line and an identification of a preliminary expression of the miRNA profile, characteristic of TOS-CSCs. These findings represent an important step in the study of the biology of one of the most aggressive variants of OS and the role of miRNAs in TOS-CSC behavior.

Circ-GALNT16 Restrains Colorectal Cancer Progression by Enhancing the SUMOylation of hnRNPK

2021 ◽  
Author(s):  
Chaofan Peng ◽  
Yuqian Tan ◽  
Peng Yang ◽  
Kangpeng Jin ◽  
Chuan Zhang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Dna Binding ◽  
Rna Sequencing ◽  
Cancer Progression ◽  
Molecular Mechanisms ◽  
Transcriptional Level ◽  
Multiple Cancer ◽  
Binding Ability ◽  
Colorectal Cancer Progression

Abstract BackgroundEmerging studies have investigated circRNAs as significant regulation factors in multiple cancer progression. Nevertheless, the biological functions and underlying mechanisms of circRNAs in colorectal cancer progression remain unclear.MethodsA novel circRNA (circ-GALNT16) was identified by microarray and qRT-PCR. A series of phenotype experiments in vitro and vivo were performed to investigate the role of circ-GALNT16 in CRC. FISH, RNA pulldown assay, RIP assay, RNA sequencing, coimmunoprecipitation, and ChIP were constructed to explore the molecular mechanisms of circ-GALNT16 in colorectal cancer.ResultsCirc-GALNT16 was downregulated in colorectal cancer and negatively correlated with poor prognosis. Circ-GALNT16 suppressed the proliferation and metastasis ability of colorectal cancer in vitro and vivo. Mechanistically, circ-GALNT16 could bind to the KH3 domain of heterogeneous nuclear ribonucleoprotein K (hnRNPK), which resulted in the SUMOylation of hnRNPK. Additionally, circ-GALNT16 could enhance the hnRNPK-p53 complex by facilitating the SUMOylation of hnRNPK. Furthermore, RNA sequencing assay identified serpin family E member 1 as the target gene of circ-GALNT16 at the transcriptional level. Rescue assays revealed that circ-GALNT16 regulated the expression of Serpine1 by inhibiting the deSUMOylation of hnRNPK mediated by SUMO specific peptidase 2 and then regulating the sequence-specific DNA binding ability of the hnRNPK-p53 transcriptional complex.ConclusionsCirc-GALNT16 suppressed CRC progression via inhibiting Serpine1 expression through adjusting the sequence-specific DNA binding ability of the SENP2-mediated hnRNPK-p53 transcriptional complex and might work as a biomarker and therapeutic target for CRC.

scholarly journals Functional analysis of synovial fluid from osteoarthritic knee and carpometacarpal joints unravels different molecular profiles

Rheumatology ◽  
2018 ◽  
Vol 58 (5) ◽  
pp. 897-907 ◽  
Author(s):  
Goncalo Barreto ◽  
Rabah Soliymani ◽  
Marc Baumann ◽  
Eero Waris ◽  
Kari K Eklund ◽  
...  
Keyword(s):  
Protein Expression ◽  
Molecular Mechanisms ◽  
Mrna Level ◽  
Digital Pcr ◽  
Label Free ◽  
Primary Chondrocytes ◽  
Functional Studies ◽  
Knee Oa ◽  
Carpometacarpal Joints

Abstract Objective In this work, we aimed to elucidate the molecular mechanisms driving primary OA. By studying the dynamics of protein expression in two different types of OA joints we searched for similarities and disparities to identify key molecular mechanisms driving OA. Methods For this purpose, human SF samples were obtained from CMC-I OA and knee joint of OA patients. SF samples were analysed by label-free quantitative liquid chromatography mass spectrometry. Disease-relevant proteins identified in proteomics studies, such as clusterin, paraoxonase/arylesterase 1 (PON1) and transthyretin were validated by enzyme-linked immunosorbent assays, and on the mRNA level by droplet digital PCR. Functional studies were performed in vitro using primary chondrocytes. Results Differential proteomic changes were observed in the concentration of 40 proteins including clusterin, PON1 and transthyretin. Immunoassay analyses of clusterin, PON1, transthyretin and other inflammatory cytokines confirmed significant differences in protein concentration in SF of CMC-I and knee OA patients, with primarily lower protein expression levels in CMC-I. Functional studies on chondrocytes unequivocally demonstrated that stimulation with SF obtained from knee OA, in contrast to CMC-I OA joint, caused a significant upregulation in pro-inflammatory response, cell death and hypertrophy. Conclusion This study demonstrates that differential expression of molecular players in SF from different OA joints evokes diverse effects on primary chondrocytes. The pathomolecular mechanisms of OA may significantly differ in various joints, a finding that brings a new dimension into the pathogenesis of primary OA.

scholarly journals Curcumin Regulates ERCC1 Expression and Enhances Oxaliplatin Sensitivity in Resistant Colorectal Cancer Cells through Its Effects on miR-409-3p

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Wei Han ◽  
Hongli Yin ◽  
Hao Ma ◽  
Yi Wang ◽  
Desong Kong ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Drug Resistance ◽  
Cancer Cells ◽  
Resistance Mechanism ◽  
Cancer Cell Line ◽  
Colorectal Cancer Cell Line ◽  
Pcr Analysis ◽  
Colorectal Cancer Cells ◽  
Ercc1 Expression

Background. Oxaliplatin (L-OHP) resistance is a major obstacle to the effective treatment of colorectal cancer. The resistance mechanism(s) of colorectal tumors to L-OHP may be related to the regulation of ERCC1 by cancer-expressed miRNAs, but no in-depth studies on the miRNAs that affect drug resistance have been performed. Curcumin (Cur) can reverse the drug resistance of cancer cells, but its effects on ERCC1 expression and miRNA profiles in colorectal cancer have not been studied. Methods. To study the regulation effect of curcumin on ERCC1 expression and its effects on miRNAs, the L-OHP-resistant colorectal cancer cell line HCT116/L-OHP was established. MTT assays were used to evaluate cell proliferation. Flow cytometry was used to investigate apoptotic induction. Western blot and RT-PCR analysis were used to evaluate the expression of drug-associated ERCC1, Bcl-2, GST-π, MRP, P-gp, and survivin. Results. HCT116//L-OHP cell lines were successfully established. The combination of L-OHP and curcumin could reduce L-OHP resistance in vitro. In addition, combination therapy inhibited the expression of ERCC1, Bcl-2, GST-π, MRP, P-gp, and survivin at the mRNA and protein level. Curcumin was found to inhibit ERCC1 through its ability to modulate miR-409-3p. Conclusion. Curcumin can overcome L-OHP resistance in colorectal cancer cells through its effects on miR-409-3p mediated ERCC1 expression.

Regulation of c-ret expression by retinoic acid in rat metanephros: implication in nephron mass control

1998 ◽  
Vol 275 (6) ◽  
pp. F938-F945 ◽  
Author(s):  
Evelyne Moreau ◽  
José Vilar ◽  
Martine Lelièvre-Pégorier ◽  
Claudie Merlet-Bénichou ◽  
Thierry Gilbert
Keyword(s):  
Retinoic Acid ◽  
Molecular Mechanisms ◽  
Kidney Development ◽  
Mrna Level ◽  
Cell Surface Receptor ◽  
Dependent Manner ◽  
All Trans Retinoic Acid ◽  
Surface Receptor ◽  
Dose Dependent

Vitamin A and its derivatives have been shown to promote kidney development in vitro in a dose-dependent fashion. To address the molecular mechanisms by which all- trans-retinoic acid (RA) may regulate the nephron mass, rat kidneys were removed on embryonic day 14( E14) and grown in organ culture under standard or RA-stimulated conditions. By using RT-PCR, we studied the expression of the glial cell line-derived neurotrophic factor (GDNF), its cell surface receptor-α (GDNFR-α), and the receptor tyrosine kinase c-ret, known to play a major role in renal organogenesis. Expression of GDNF and GDNFR-α transcripts was high at the time of explantation and remained unaffected in culture with or without RA. In contrast, c-ret mRNA level, which was low in E14 metanephros and dropped rapidly in vitro, was increased by RA in a dose-dependent manner. The same is true at the protein level. Exogenous GDNF barely promotes additional nephron formation in vitro. Thus the present data establish c-ret as a key target of retinoids during kidney organogenesis.

scholarly journals Antiproliferative activity and caspase enhancement properties of Annona muricata leaves extract against colorectal cancer cells

2016 ◽  
Vol 25 (3) ◽  
pp. 136-42
Author(s):  
Lili Indrawati ◽  
Purwantyastuti Ascobat ◽  
Budiman Bela ◽  
Murdani Abdullah ◽  
Ingrid S. Surono ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Line ◽  
Cancer Cell ◽  
Water Extract ◽  
Cancer Cell Line ◽  
Colorectal Cancer Cell ◽  
Colorectal Cancer Cell Line ◽  
Annona Muricata ◽  
Caspase 9

Background: The prevalence of colorectal cancer is rising in Asia including Indonesia. Annona muricata tea leaves, that is traditionally used for maintaining health, and lately being used by cancer patients. The objectives of this study is to investigate its effects in human colorectal cancer cell in vitro and ex vivo.Methods: Thirty patients with colorectal cancer (CRC) were enrolled in a randomized double-blind placebo-controlled trial. They were equally divided into two groups: those treated with 300 mg A. muricata leaf extract and placebo daily for 8 weeks. Serum from supplemented CRC patients of both groups was compared for caspase 9 and caspase 8 enhancement activity. Antiproliferative effect of water extract of A. muricata leaves and its fractions were evaluated against colorectal cancer cell line (DLD-1 and COLO 205) compared with 5-fluorouracil and placebo, the dose range was 62.5-2,000 µg/mL. Method used was 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Data were analyzed by Mann-Whitney U test. The p value was set at 0.05.Results: Ethanol-soluble fraction of A. muricata leaves extract water extract (ESFAM) leaves extract had cytotoxicity effects on DLD-1 as well as COLO 205 cell line, as shown by the lower IC50 compared to 5-fluorouracil and placebo, 20.59 μg/mL and 654.9μg/mL, respectively. Serum of subjects supplemented with extract significantly induced caspase 9 (p=0.001) activity of DLD-1 colorectal cancer cell line, but not for caspase 8 activity (p=0.372).Conclusion: The study's results suggest the cytotoxicity potential of  A. muricata  leaves extract  in in vitro and ex vivo studies.

A novel Sp1-relatedciselement involved in intestinal alkaline phosphatase gene transcription

1999 ◽  
Vol 276 (4) ◽  
pp. G800-G807 ◽  
Author(s):  
Jeong H. Kim ◽  
Shufen Meng ◽  
Amy Shei ◽  
Richard A. Hodin
Keyword(s):  
Alkaline Phosphatase ◽  
Transcriptional Activation ◽  
Molecular Mechanisms ◽  
Regulatory Element ◽  
Gene Activation ◽  
Regulatory Region ◽  
Intestinal Alkaline Phosphatase ◽  
Mobility Shift ◽  
Sv40 Promoter

We have used sodium butyrate-treated HT-29 cells as an in vitro model system to study the molecular mechanisms underlying intestinal alkaline phosphatase (IAP) gene activation. Transient transfection assays using human IAP-CAT reporter genes along with DNase I footprinting were used to localize a critical cis element (IF-III) corresponding to the sequence 5′-GACTGGGCGGGGTCAAGATGGA-3′. Deletion of the IF-III element resulted in a dramatic reduction in reporter gene activity, and IF-III was shown to function in the context of a heterologous (SV40) promoter in a cell type-specific manner, further supporting its functional role in IAP transactivation. Electrophoretic mobility shift assays revealed that IF-III binds Sp1 and Sp3, but these factors comprise only a portion of the total nuclear binding and appear to mediate only a small portion of its transcriptional activity. IF-III does not correspond to any previously characterized regulatory region from other intestine-specific genes. We have thus identified a novel, Sp1-related cis-regulatory element in the human IAP gene that appears to play a role in its transcriptional activation during differentiation in vitro.

Synthesis, Characterization and Biological Studies of a Organoselenium trans-Palladium(II) Complexes

2020 ◽  
Vol 16 ◽  
Author(s):  
Ivana Raković ◽  
Jovana Bogojeski ◽  
Katarina Mladenović ◽  
Angelina Petrović ◽  
Vera Divac ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Cancer Cell Line ◽  
Colorectal Cancer Cell Line ◽  
Spectral Studies ◽  
Cytotoxic Effects ◽  
Hct 116

Background: Over the years, transition metal complexes have exhibited significant antimicrobial and antitumor activity. It all started with cisplatin discovery, but due to the large number of side effects it shows, there is a growing need to find a new metal-based compound with higher selectivity and activity on more tumors. Objectives: Two novel trans-palladium(II) complexes with organoselenium compounds as ligands, [Pd(L1)2Cl2] (L1 = 5- (phenylselanylmethyl)-dihydrofuran-2(3H)-one) and [Pd(L2)2Cl2] (L2 = 2-methyl-5-(phenylselanylmethyl)- tetrahydrofuran) were synthesized, in the text referred to as Pd-Se1 and Pd-Se2. Also, a structurally similar trans-palladium(II) complex, [Pd(L3)2Cl2] (L3= 2,2-dimethyl-3-(phenylselanylmethyl)-tetrahydro-2H-pyran ) was synthesized according to an already published work and is referred to as Pd-Se3. The interaction of synthesized complexes with DNA and bovine serum albumin were done. Also, antimicrobial activity and in vitro testing, cell viability, and cytotoxic effects of synthesized ligands and complexes on human epithelial colorectal cancer cell line HCT-116 were studied. Molecular docking simulations were performed to understand better the binding modes of the complexes reported in this paper with DNA and BSA, as well as to comprehend their antimicrobial activity. Methods: The interactions of the synthesized complexes with DNA and bovine serum albumin were done using UV-Vis and emission spectral studies as well as docking studies. Antimicrobial activity was tested by determining the minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) using the resazurin microdilution plate method. Cytotoxic activity on cancer cells was studied by MTT test. Results: The Pd(II) complexes showed a significant binding affinity for calf thymus DNA and bovine serum albumin by UV-Vis and emission spectral studies. The intensity of antimicrobial activity varied with the complexes Pd-Se1 and Pd-Se3, showing significantly higher activity than the corresponding ligand. The most significant activity was shown on Pseudomo-nas aeruginosa. Under standardized laboratory conditions for in vitro testing, cell viability and cytotoxic effects of synthesized ligands and complexes were studied on human epithelial colorectal cancer cell line HCT-116, where Pd-Se2 showed some significant cytotoxic effects. Conclusion: The newly synthesized complexes have the potential to be further investigated as metallodrugs.

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