| 1. |
- Al-Haidari, Amr, et al.
(author)
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MiR-155-5p controls colon cancer cell migration via post-transcriptional regulation of Human Antigen R (HuR)
- 2018
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In: Cancer Letters. - : Elsevier BV. - 0304-3835. ; 421, s. 145-151
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Journal article (peer-reviewed)abstract
- Colorectal cancer (CRC) is the third most common cancer and a significant cause of cancer-related deaths worldwide. Metastasis is the worst prognostic factor for patients with CRC. HuR (ELAVL1) is overexpressed in CRC and has been reported to promote colon cancer growth by targeting RNA in the cell cytoplasm. Herein, the role of miR-155-5p in regulating HuR expression and cell migration was examined in colon cancer cells. MiR-155-5p knockdown in serum-starved colon cancer cells decreased both colon cancer cell chemotaxis and cytoplasmic expression of HuR. Bioinformatics analysis predicted two putative binding sites in the AU-rich elements (AREs) at the 3′-UTR of HuR mRNA. MiR-155-5p binding to HuR was verified using specific target site blockers and functionally validated by use of RNA immunoprecipitation assays, showing that miR-155-5p-dependent regulation of HuR expression is mediated by AREs. Targeting AREs with a specific blocker inhibited colon cancer cell migration. Taken together, these novel findings demonstrate that AREs mediate miR-155-5p positive regulation of HuR mRNA levels and translation as well as migration in colon cancer cells, suggesting that targeting miR-155-5p and/or Hur might be useful therapeutic strategies against colon cancer metastasis.
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| 2. |
- Algaber, Anwar, et al.
(author)
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MicroRNA-340-5p inhibits colon cancer cell migration via targeting of RhoA
- 2020
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In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1, s. 16934-16934
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Journal article (peer-reviewed)abstract
- Colon cancer is the third most common cancer and a significant cause of cancer-related deaths worldwide. Metastasis is the most insidious aspect of cancer progression. Convincing data suggest that microRNAs (miRs) play a key function in colon cancer biology. We examined the role of miR-340-5p in regulating RhoA expression as well as cell migration and invasion in colon cancer cells. Levels of miR-340-5p and RhoA mRNA varied inversely in serum-free and serum-grown HT-29 and AZ-97 colon cancer cells. It was found transfection with miR-340-5p not only decreased expression of RhoA mRNA and protein levels in HT-29 cells but also reduced colon cancer cell migration and invasion. Bioinformatics analysis predicted one putative binding sites at the 3'-UTR of RhoA mRNA. Targeting this binding site with a specific blocker reversed mimic miR-340-5p-induced inhibition of RhoA activation and colon cancer cell migration and invasion. These novel results suggest that miR-340-5p is an important regulator of colon cancer cell motility via targeting of RhoA and further experiments are warranted to evaluate the role of miR-340-5p in colon cancer metastasis.
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| 3. |
- Algaber, Anwar
(author)
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MicroRNA-Mediated Migration of Colon Cancer Cells
- 2021
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Doctoral thesis (other academic/artistic)abstract
- Colorectal cancer (CRC) is the second most common cancer in women and third most common cancer in men worldwide. The cause of the majority of death related to CRC is believed to be the migration of cancer cells to distant organs which is known as cancer metastasis. The mechanism behind cancer cell metastasis is not fully understood but accumulating studies suggest that it could be due to enhanced tumor cell motility due to overexpression of metastasis related proteins. It is believed that microRNAs (miRNAs) play a significant role in the tumorigenesis and metastasis of cancer by regulating oncogenes. The aim of this thesis is to investigate the mechanism of miRNA-mediated colon cancer cell invasion and migration as well as possible targets genes of miRNAs. We found that knockdown of miR-155-5p by antagomiR reduces the expression of HuR mRNA and migration of colon cancer cells. Our data also showed that miR-155-5p is involved in positive regulation of HuR protein under stress conditions. Notably, this positive regulation is regulated by direct binding of miR-155-5p at AU rich element region in 3ʹ-UTR of HuR mRNA. In addition, it was found that miR-340-5p is also involved in colon cancer cell invasion and migration by regulating RhoA and FHL2 mRNA expression. Bioinformatics analysis revealed that both RhoA and FHL2 mature mRNA have conserved binding sites from 2 to 8 base positions for miR-340-5p. The seed region of miR-340-5p directly binds with the target sites of RhoA and FHL2 mRNA and negatively regulate their expression under stress conditions. We found that the inhibition of RhoA and FHL2 expression by the use of mimic miR-340-5p reduced colon cancer cells invasion and migration. In addition, it was found that inhibition of FHL2 reduces cancer cells proliferation and increases E-cadherin expression in colon cancer cells, suggesting that targeting FHL2 and RhoA by miR-340-5p might be a useful approach to antagonize colon cancer cells metastasis. The results of our studies not only show diverse mechanisms of colon cancer cells migration, but also provided valuable information that miRNAs can be an important target to develop new and effective therapeutics against colon cancer cells metastasis. Taken together, our data uncovered several new mechanisms for better understanding the mechanism of colon cancer cells metastasis and suggest that targeting miRNAs function could be a useful strategy to prevent colon cancer metastasis.
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| 4. |
- Algaber, Anwar, et al.
(author)
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Targeting FHL2-E-cadherin axis by miR-340-5p attenuates colon cancer cell migration and invasion
- 2021
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In: Oncology Letters. - : Spandidos Publications. - 1792-1074 .- 1792-1082. ; 22:2
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Journal article (peer-reviewed)abstract
- Convincing data has suggested that four and a half LIM domain 2 protein (FHL2) serves a key function in cancer cell metastasis and that microRNA (miR)-340-5p can regulate cancer cell migration. The current study hypothesized that targeting FHL2 expression by miR-340-5p in colon cancer may attenuate colon cancer cell migration and invasion. FHL2 expression was therefore assessed in colon cancer microarray datasets using Qlucore omics explorer as well as in HT-29 and AZ-97 colon cancer cell lines via reverse transcription-quantitative PCR (RT-qPCR). Colon cancer cell migration and invasion were evaluated in the presence of miR-340-5p mimic, mimic control or mimic with a target site blocker. Confocal microscopy and RT-qPCR were subsequently performed to assess FHL2, E-cadherin (E-cad) protein and mRNA expression in colon cancer cells. Microarray dataset analysis revealed that FHL2 expression was lower in primary colon cancer cells compared with normal colonic mucosa. It was revealed that the expression of miR-340-5p and FHL2 were inversely related in serum-grown and low-serum conditions in HT-29 and AZ-97 cells. Short-time serum exposure to low-serum grown cells induced FHL2 expression. Transfection of HT-29 cells with miR-340-5p mimic not only decreased serum-induced expression of FHL2 but also decreased cancer cell migration and invasion. Bioinformatics analysis revealed that FHL2 mRNA had one putative binding site for miR-340-5p at the 3-untranslated region. Blocking of the target site using a specific blocker reverted miR-340-5p mimic-induced inhibition of FHL2 expression and cancer cell migration and invasion. Confocal microscopy confirmed that the reduction of FHL2 expression by miR-340-5p mimic also reversed serum-induced E-cad disruption and that the target site blocker abrogated the effect of miR-340-5p. The current results suggested that miR-340-5p could be used to antagonize colon cancer cell metastasis by targeting the FHL2-E-cad axis.
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| 5. |
- Hawez, Avin, et al.
(author)
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MiR-155 regulates neutrophil extracellular trap formation and lung injury in abdominal sepsis
- 2022
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In: Journal of Leukocyte Biology. - 1938-3673. ; 111:2, s. 391-400
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Journal article (peer-reviewed)abstract
- Neutrophil extracellular traps (NETs)-mediated tissue damage is a hallmark in abdominal sepsis. Under certain conditions, microRNAs (miRs) can regulate protein expression and cellular functions. The aim of this study was to investigate the role of miR-155 in sepsis-induced NET formation, lung inflammation, and tissue damage. Abdominal sepsis was induced in wild-type (WT) C57BL/6 and miR-155 gene-deficient mice by cecal ligation and puncture (CLP). The amount of DNA-histone complex formation as well as myeloperoxidase (MPO) and citrullinated histone 3 in neutrophils isolated from bone marrow were examined by ELISA and flow cytometry. NETs were detected by electron microscopy in the septic lung. Levels of PAD4 and citrullinated histone 3 were determined by Western blot in the blood neutrophils. Lung levels of MPO, CXC chemokines, and plasma levels of DNA-histone complexes and CXC chemokines were quantified. In vitro studies revealed that neutrophils from miR-155 gene-deficient mice had less NETs forming ability than WT neutrophils. In the miR-155 gene-deficient mice, CLP yielded much less NETs in the lung tissue compared with WT control. CLP-induced PAD4 levels, histone 3 citrullination, edema, MPO activity, and neutrophil recruitment in the lung were markedly reduced in the mice lacking miR-155. Furthermore, tissue and plasma levels of CXCL1 and CXCL2 were significantly lower in the miR-155 gene-deficient mice compared with WT after induction of abdominal sepsis. Taken together, our findings suggest that miR-155 regulates pulmonary formation of NETs in abdominal sepsis via PAD4 up-regulation and histone 3 citrullination. Thus, targeting miR-155 could be a useful target to reduce pulmonary damage in abdominal sepsis.
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| 6. |
- Lepsenyi, Mattias, et al.
(author)
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CXCL2-CXCR2 axis mediates αV integrin-dependent peritoneal metastasis of colon cancer cells
- 2021
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In: Clinical and Experimental Metastasis. - : Springer Science and Business Media LLC. - 1573-7276 .- 0262-0898. ; 38:4, s. 401-410
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Journal article (peer-reviewed)abstract
- Peritoneal metastasis is an insidious aspect of colorectal cancer. The aim of the present study was to define mechanisms regulating colon cancer cell adhesion and spread to peritoneal wounds after abdominal surgery. Mice was laparotomized and injected intraperitoneally with CT-26 colon carcinoma cells and metastatic noduli in the peritoneal cavity was quantified after treatment with a CXCR2 antagonist or integrin-αV-antibody. CT-26 cells expressed cell surface chemokine receptors CXCR2, CXCR3, CXCR4 and CXCR5. Stimulation with the CXCR2 ligand, CXCL2, dose-dependently increased proliferation and migration of CT-26 cells in vitro. The CXCR2 antagonist, SB225002, dose-dependently decreased CXCL2-induced proliferation and migration of colon cancer cells in vitro. Intraperitoneal administration of CT-26 colon cancer cells resulted in wide-spread growth of metastatic nodules at the peritoneal surface of laparotomized animals. Laparotomy increased gene expression of CXCL2 at the incisional line. Pretreatment with CXCR2 antagonist reduced metastatic nodules by 70%. Moreover, stimulation with CXCL2 increased CT-26 cell adhesion to extracellular matrix (ECM) proteins in a CXCR2-dependent manner. CT-26 cells expressed the αV, β1 and β3 integrin subunits and immunoneutralization of αV abolished CXCL2-triggered adhesion of CT-26 to vitronectin, fibronectin and fibrinogen. Finally, inhibition of the αV integrin significantly attenuated the number of carcinomatosis nodules by 69% in laparotomized mice. These results were validated by use of the human colon cancer cell line HT-29 in vitro. Our data show that colon cancer cell adhesion and growth on peritoneal wound sites is mediated by a CXCL2-CXCR2 signaling axis and αV integrin-dependent adhesion to ECM proteins.
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