scholarly journals Autophagy Overactivity Regulate Terf1 and Terf2 in Positive and Negative-Telomerase Cancer Cell Lines

Author(s):  
mohammad panahi ◽  
Saeed Samani ◽  
Nasrin Mohajeri ◽  
Akram Sadat Tabatabee Bafroee ◽  
Kazem Baesi ◽  
...  

Abstract A recent suggestion for cancer therapy is targeting intracellular homeostatic signaling pathways like autophagy providing the balance between metabolism and cell cycling. Our study focused on investigating the relationship between autophagy activation by Beclin1 transfection and assessing Terf1 and Terf2 expression as shelterin proteins. The beclin1-containing plasmid was introduced to the U-2OS and Huh7 cell lines using Lipofectamine. The LC3-II as an intracellular autophagosomal marker was detected in transfected cells by flow cytometry. Also, the cells were treated with 3-methyladenine and metformin as autophagy inhibitors and inducers, respectively. Finally, the expression levels of Terf1 and Terf2 were analyzed by real-time PCR. Fluorescent images and flow cytometry results proved excellent GFP expression in the transfected cells. The results of real-time PCR demonstrated that autophagy induction by Beclin1 was increased Terf1 expression level in U-2OS cells up to 451%, while Huh7 cells suffered from the decreased expression of Terf1. Altogether, Terf2 expression was enhanced significantly in both cell lines after 48h treatment in comparison with 24h treatment. The obtained data provided that Beclin1-based activation of autophagy leads to overexpression of some protective shelterin proteins.

2020 ◽  
Vol 9 ◽  
pp. 1896
Author(s):  
Maedeh Olya ◽  
Hamid Zaferani Arani ◽  
Amirhossein Shekarriz ◽  
Amirhossein Zabolian ◽  
Hadi Zare Marzouni ◽  
...  

Background: Hepatocellular carcinoma is the most common type of liver cancer which arises from the main cells in the liver. We address many studies investigating anti-cancer role of hypericin, however the proposing corresponding molecular pathway seems to be still a debate. Therefore, the present study aimed to evaluate the apoptotic effect of hypericin on the Huh7 as the liver cancer cell line and its relation with the gate keeper gene P53. Materials and Methods: In this study, the Huh7 cell line and fibroblast cells (as control group) were treated with different concentrations of hypericin for 24 and 48 hours. Detection of cell death was performed by MTT assay and flow cytometry. The expression of bax, bcl2 and p53 mRNAs was evaluated by Real-time PCR. Also, Immunocytochemistry (ICC) analysis was used for further evaluation of P53expression. Results: The results showed that hypericin has a dose-dependent cytotoxic effect on the Huh7 cell line, with no or marginal effect on fibroblastic cells. According to flow cytometry results, about 53%cells underwent apoptosis after exposure to LD50 of hypericin for 24 hours. Real-time PCR data demonstrated that the pro-apoptotic genes Bax and P53 expression level increased. Expectedly ICC results confirmed the up-regulation of P53 proteins in treated samples. Conclusion: Our results indicate the cytotoxicity of hypericin on Huh7 cells by affecting the expression of the gate keeper gene P53; furthermore it is suggested that this herb can be utilized simultaneously with modalities targeting P53 up-regulation or related molecular pathways. [GMJ.2020;9:e1896]


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4547-4547
Author(s):  
Huanling Zhu ◽  
Ting Liu ◽  
Yongqian Jia

Abstract Objective To establish an imatinib resistance cell line and to study its resistant principia. Methods K562 cells were cultured in imatinib at gradually increased concentrations to generate their resistance cell line. Clone imatinib resistance cell lines by limited dilution culture. MTT assay, real time PCR and Semi-quantity PCR, flow cytometry and HPLC were used to clarify the possible mechanisms of the resistance. Results Imatinib resistance cell line K562R was successfully induced by continuous culture in the presence of gradually increasing doses of imatinib up to 5μmol/L. K562R cells were maintained in the media containing 5μmol/L imatinib. Proliferation data showed that cell growth of K562R was not inhibited in 5 μmol/L imatinib, whereas the parental sensitive cell was significantly inhibited by up to 2μM imatinib. The IC50 of K562R was about 7.5μmol/L which was ten times higher than that of the parental cell. HPLC revealed that the intracellular imatinib concentration of K562R was strikingly lower than that of the parental cells (up to 27.8-fold). MDR1 were not detected in mRNA (by RT-PCR)and protein(by flow cytometry) levels on K562R cell, whereas hOCT1 level measured by semi-quantity PCR showed lower expression in K562R cell lines than that of parental sensitive cell, indicating that low intracellular imatinib concentration may be due to lower affluence of imatinib by low level of hOCT1. (5) Real time PCR analysis showed no BCR-ABL/G6PD gene amplification and sequence analysis of the 374bp ABL kinase domain showed no mutation in K562R cell lines. Conclusion An imatinib resistance cell line K562R has been successfully established. Low expression of hOCT1 may be a key point mediating low intracellular imaitnib accumulation in K562R cell lines.


Cancers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2341
Author(s):  
Normann Steiner ◽  
Karin Jöhrer ◽  
Selina Plewan ◽  
Andrea Brunner-Véber ◽  
Georg Göbel ◽  
...  

Therapy resistance remains a major challenge in the management of multiple myeloma (MM). We evaluated the expression of FLT3 tyrosine kinase receptor (FLT3, CD135) in myeloma cells as a possible clonal driver. FLT3 expression was analyzed in bone marrow biopsies of patients with monoclonal gammopathy of undetermined significance or smoldering myeloma (MGUS, SMM), newly diagnosed MM (NDMM), and relapsed/refractory MM (RRMM) by immunohistochemistry (IHC). FLT3 gene expression was analyzed by RNA sequencing (RNAseq) and real-time PCR (rt-PCR). Anti-myeloma activity of FLT3 inhibitors (midostaurin, gilteritinib) was tested in vitro on MM cell lines and primary MM cells by 3H-tymidine incorporation assays or flow cytometry. Semi-quantitative expression analysis applying a staining score (FLT3 expression IHC-score, FES, range 1–6) revealed that a high FES (>3) was associated with a significantly shorter progression-free survival (PFS) in NDMM and RRMM patients (p = 0.04). RNAseq and real-time PCR confirmed the expression of FLT3 in CD138-purified MM samples. The functional relevance of FLT3 expression was corroborated by demonstrating the in vitro anti-myeloma activity of FLT3 inhibitors on FLT3-positive MM cell lines and primary MM cells. FLT3 inhibitors might offer a new targeted therapy approach in a subgroup of MM patients displaying aberrant FLT3 signaling.


2007 ◽  
Vol 29 (4) ◽  
pp. 289-299
Author(s):  
Robert E. Page ◽  
Andrés J. P. Klein-Szanto ◽  
Samuel Litwin ◽  
Emmanuelle Nicolas ◽  
Raid Al-Jumaily ◽  
...  

Background: Proprotein convertases (PCs) are serine proteases that after restricted proteolysis activate many proteins that play a crucial role in cancer such as metalloproteinases, growth factors and growth factor receptors, adhesion molecules, and angiogenic factors. Although the expression of several PCs is increased in many tumors, their expression in primary ovarian tumors has not been studied in detail. We sought to determine if there was an association between the expression of the ubiquitously expressed PCs, furin, PACE-4, PC-5 and PC-7, and ovarian tumor progression. Methods: We assessed their expression by RT-PCR, Real-time PCR, Western blot, and immunohistochemistry using cells derived from normal human ovarian surface epithelium (HOSE) and cancer cell lines as well as ovarian epithelial cancer specimens (45 RT-PCR/Real-time PCR, and 120 archival specimens for Immunohistochemistry). Results: We found that furin expression was restricted to the cancer cell lines. In contrast, PACE-4 and PC-7 showed expression only in normal HOSE cells lines. Furthermore, furin was predominantly expressed in primary tumors from patients who survived for less than five years. The other PCs are either expressed in the group of survivors (PC-7 and PACE4) or expressed in low amounts (PC-5). Conclusions: Our studies point to a clear relationship between furin and ovarian cancer. In addition, these results show that furin exhibits the closest association with ovarian cancer among the ubiquitously expressed PCs, arguing against the redundancy of these proteases. In summary, furin may constitute a marker for ovarian tumor progression and could contribute to predict the outcome of this disease.


Author(s):  
Linh Thi Nhut Tran ◽  
My Thi Huynh Nguyen ◽  
Linh Nguy Hoang Le ◽  
Khoa Dang Le ◽  
Minh Hoang Nhat Nguyen ◽  
...  

rs1801133 is a single nucleotide polymorphism (SNP) located in the sequence of MTHFR on human chromosome 1. The alleles of this SNP affect the activity of the MTHFR enzyme. People bearing C/T genotype have 66% activity of MTHFR while people with T/T genotype have only 25% activity. These reduced activities of MTHFR cause homocysteinemia. There are several publications on the relationship between homocysteinemia and human diseases such as cardiovascular disease, neurological diseases, abnormal fetus, infertility and cancer. In this study, we built a molecular protocol for genotyping rs1801133 using real-time PCR HRM technique. This protocol could be used for diagnosis of molecular mechanism of homocysteinemia causing the mentoned above diseases as well as for the study of the relationship between rs1801133 and other human diseases. We successfully designed the primer pairs for genotyping and nucleotide sequencing rs1801133 by real-time PCR HRM and Sanger sequencing method. We also examined the optimal MgCl2 concentration for clear differentiation of three rs1801133 genotypes. Performance characteristics of the real-time PCR HRM protocol included of specificity, repeatability, reproducibility was evaluated and it showed good results. Comparison of genotyping results of rs1801133 between the realtime PCR HRM method and the Sanger nucleotide sequencing method showed good concordances. Finally, this real-time PCR HRM protocol for rs1801133 genotyping was applied on 100 human DNA samples to evaluate the clinical utility of the protocol.


2006 ◽  
Vol 72 (6) ◽  
pp. 4323-4328 ◽  
Author(s):  
R. Temmerman ◽  
H. Vervaeren ◽  
B. Noseda ◽  
N. Boon ◽  
W. Verstraete

ABSTRACT This study examined whether Legionella pneumophila is able to thrive on heat-killed microbial cells (necrotrophy) present in biofilms or heat-treated water systems. Quantification by means of plate counting, real-time PCR, and flow cytometry demonstrated necrotrophic growth of L. pneumophila in water after 96 h, when at least 100 dead cells are available to one L. pneumophila cell. Compared to the starting concentration of L. pneumophila, the maximum observed necrotrophic growth was 1.89 log units for real-time PCR and 1.49 log units for plate counting. The average growth was 1.57 � 0.32 log units (n = 5) for real-time PCR and 1.14 � 0.35 log units (n = 5) for plate counting. Viability staining and flow cytometry showed that the fraction of living cells in the L. pneumophila population rose from the initial 54% to 82% after 96 h. Growth was measured on heat-killed Pseudomonas putida, Escherichia coli, Acanthamoeba castellanii, Saccharomyces boulardii, and a biofilm sample. Gram-positive organisms did not result in significant growth of L. pneumophila, probably due to their robust cell wall structure. Although necrotrophy showed lower growth yields compared to replication within protozoan hosts, these findings indicate that it may be of major importance in the environmental persistence of L. pneumophila. Techniques aimed at the elimination of protozoa or biofilm from water systems will not necessarily result in a subsequent removal of L. pneumophila unless the formation of dead microbial cells is minimized.


2021 ◽  
Vol 34 (Supplement_1) ◽  
Author(s):  
Manuel Pera ◽  
Marta Garrido ◽  
Gabriel Gil ◽  
Matteo Fassan ◽  
Marta Climent ◽  
...  

Abstract   Cardiac-type epithelium has been proposed as an intermediate stage between normal squamous epithelium and intestinal metaplasia in the development of Barrett’s esophagus. Deregulation of certain miRNAs and their effects on CDX2 expression might contribute to the intestinalization process of cardiac-type epithelium. The aim of this study was to identify miRNAs differentially expressed between CDX2 positive and negative glands of Barrett’s esophagus and to examine the function of specific miRNAs on the regulation of CDX2. Methods miRNA expression profiling using OpenArrayTM analysis in microdissected cardiac-type glands with and without fully CDX2 expression was performed in biopsies from patients who developed cardiac-type epithelium in the remnant esophagus after esophagectomy. Data were validated using real-time PCR in esophageal adenocarcinoma cell lines and in situ and real-time PCR miRNA/CDX2/MUC2 co-expression analysis in cardiac-type mucosa samples. The effect of miR-24-3p precursor transfection on CDX2 expression was assessed in the esophageal adenocarcinoma cell lines FLO-1 and KYAE-1. Results CDX2 positive glands were characterized by an unique miRNA profile with a significant downregulation of miR-24-3p, miR-520e-3p, miR-548a-1, miR-597-5p, miR-133a-3p, miR-30a-5p, miR-638, miR-625-3p, miR-1255b-1, miR-1260a and upregulation of miR-590 (Figure 1A). miRNA-24-3p was identified as potential regulator of CDX2 gene expression in three bioinformatics algorithms, and this was confirmed in esophageal adenocarcinoma cell lines (Figure 1C). Furthermore, miR-24-3p expression negatively correlates with CDX2 in cardiac-type mucosa samples with different stages of mucosal intestinalization (Figure 1B). Conclusion These results imply that miRNA-24-3p directly targets CDX2, and downregulation of miRNA-24-3p is associated with the acquisition of an intestinal phenotype in cardiac-type epithelium.


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