scholarly journals The adenoviral E1B-55k protein present in HEK293 cells mediates abnormal accumulation of key WNT signaling proteins in large cytoplasmic aggregates

2021 ◽  
Author(s):  
Petter Angell Olsen ◽  
Stefan Krauss
Keyword(s):  
Wnt Signaling ◽  
Cell Line ◽  
Signaling Pathway ◽  
Transcriptional Activation ◽  
Cellular Localization ◽  
Hek293 Cell ◽  
Wnt Signaling Pathway ◽  
Hek293 Cells ◽  
Protein Levels ◽  
Hek293 Cell Line

Abstract HEK293 cells are one of the most widely used cell lines in research and HEK293 cells are frequently used as an in vitro model for studying the WNT signaling pathway. The HEK293 cell line was originally established by transfection of human embryonic kidney cells with sheared adenovirus 5 DNA and it is known that that HEK293 cells stably express the adenoviral E1A and E1B-55k proteins. Here we show that HEK293 cells display an unexpected distribution of key components of the WNT/β-catenin signaling pathway where AXIN1, APC, DVL2 and tankyrase are all co-localized in large spherical cytoplasmic aggregates. The cytoplasmic aggregates are enclosed by a narrow layer of the adenoviral E1B-55k protein. Reduction of E1B-55k protein levels leads to disappearance of the cytoplasmic aggregates thus corroborating an essential role of the E1B-55k protein in mediating the formation of the aggregates. Furthermore, HEK293 cells with reduced E1B-55k protein levels display reduced levels of transcriptional activation of WNT/β-catenin signaling upon stimulation by the Wnt3A agonist. The demonstrated influence of the E1B-55k protein on the cellular localization of WNT/β-catenin signaling components and on transcriptional regulation of WNT/β-catenin signaling asks for caution in the interpretation of data derived from the HEK293 cell line.

Evaluation of MACF1-regulatory non-coding RNA as a potential therapeutic target in Colorectal Cancer

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Rowaida Mohammed Reda M. M Aboushahba ◽  
Fayda Ibrahim Abdel Motaleb ◽  
Ahmed Abdel Aziz Abou-Zeid ◽  
Enas Samir Nabil ◽  
Dalia Abdel-Wahab Mohamed ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Proliferation ◽  
Wnt Signaling ◽  
Cell Line ◽  
Signaling Pathway ◽  
Therapeutic Target ◽  
Molecular Mechanisms ◽  
Wnt Signaling Pathway ◽  
Control Group ◽  
Potential Therapeutic Target

ABSTRACT Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths world-wide. There is an increasing need for the identification of novel biomarkers/targets for early diagnosis and for the development of novel chemopreventive and therapeutic agents for CRC. Recently, MACF1 gene has emerged as a potential therapeutic target in cancer as it involved in processes critical for tumor cell proliferation, invasion and metastasis. It is suggested that MACF1 may function in cancers through Wnt signaling. MiR-34a is a well-known tumor suppressor miRNA.miR-34a targets MACF1 gene as a part of the wnt signaling pathway. In this study, 40 colonic tissues were collected from CRC patients (20) and control subjects (20). miR-34a-5p was assessed by real time PCR in all study groups. The results showed highly significant decrease (P < 0.01) in miR-34a relative expression in the CRC group (median RQ 0.13) when compared to the benign group (median RQ 5.3) and the healthy control group (median RQ 19.63). miR-34a mimic and inhibitor were transfected in CaCo-2 cell line and proliferation was assessed. The transfection of the cell line with miR-34a mimic decreased cell proliferation. Our study suggests that miR-34a-5p targets MACF1 gene as a part of the wnt signaling pathway leading to the involvement in the molecular mechanisms of CRC development and progression.

scholarly journals The microRNA miR-8 is a conserved negative regulator of Wnt signaling

2008 ◽  
Vol 105 (40) ◽  
pp. 15417-15422 ◽  
Author(s):  
Jennifer A. Kennell ◽  
Isabelle Gerin ◽  
Ormond A. MacDougald ◽  
Ken M. Cadigan
Keyword(s):  
Wnt Signaling ◽  
Signaling Pathway ◽  
Target Genes ◽  
Wnt Signaling Pathway ◽  
Negative Regulator ◽  
Animal Development ◽  
Protein Levels ◽  
Evolutionarily Conserved ◽  
Multiple Levels

Wnt signaling plays many important roles in animal development. This evolutionarily conserved signaling pathway is highly regulated at all levels. To identify regulators of the Wnt/Wingless (Wg) pathway, we performed a genetic screen in Drosophila. We identified the microRNA miR-8 as an inhibitor of Wg signaling. Expression of miR-8 potently antagonizes Wg signaling in vivo, in part by directly targeting wntless, a gene required for Wg secretion. In addition, miR-8 inhibits the pathway downstream of the Wg signal by repressing TCF protein levels. Another positive regulator of the pathway, CG32767, is also targeted by miR-8. Our data suggest that miR-8 potently antagonizes the Wg pathway at multiple levels, from secretion of the ligand to transcription of target genes. In addition, mammalian homologues of miR-8 promote adipogenesis of marrow stromal cells by inhibiting Wnt signaling. These findings indicate that miR-8 family members play an evolutionarily conserved role in regulating the Wnt signaling pathway.

scholarly journals Comparative Genomics, Infectivity and Cytopathogenicity of American Isolates of Zika Virus that Developed Persistent Infections in Human Embryonic Kidney (HEK293) Cells

2019 ◽  
Vol 20 (12) ◽  
pp. 3035 ◽  
Author(s):  
Hebing Liu ◽  
Hsiao-Mei Liao ◽  
Bingjie Li ◽  
Shien Tsai ◽  
Guo-Chiuan Hung ◽  
...  
Keyword(s):  
Cell Line ◽  
Zika Virus ◽  
Hek293 Cell ◽  
Clonal Selection ◽  
Gene Mutations ◽  
Host Cells ◽  
Hek293 Cells ◽  
Specific Gene ◽  
Human Embryonic Kidney ◽  
Hek293 Cell Line

Zika virus (ZIKV) transmission can cause serious fetal neurological abnormalities. ZIKV persistence in various human cells and tissues can serve as infectious reservoirs and post serious threats to public health. The human embryonic kidney (HEK293) cell line with known neuronal developmental properties was readily infected by ZIKV in a strain-dependent fashion. Significant cytopathic effect in HEK293 cells infected by the prototype MR 766 strain of ZIKV resulted in complete loss of cells, while small numbers of HEK293 cells infected by contemporary ZIKV isolates (PRV or FLR strain) continued to survive and regrow to confluency in the culture around two months after initial infection. Most, if not all, of the cells in the two resulting persistently ZIKV-infected HEK293 cell lines tested positive for ZIKV antigen. Compared to HEK293 control cells, the persistently ZIKV-infected HEK293 cells had slower growth rates with some cells undergoing apoptosis in culture. The “persistent ZIKVs” produced constitutively by both PRV and FLR strains ZIKV-infected HEK293 cells had significantly attenuated cell infectivity and/or cytopathogenicity. Comparative genome sequence analyses between the persistent ZIKVs and the original inoculum ZIKVs showed no clonal selection with specific gene mutations in the prolonged process of establishing persistently PRV strain ZIKV-infected HEK293 cells; while selection of ZIKV subclones with mutations in the envelope, protein pr and multiple NS genes was evident in developing persistently FLR strain ZIKV-infected HEK293 cell line. Our study provides molecular insights into the complex interplays of ZIKV and human host cells in establishing ZIKV persistence.

scholarly journals MTA3 regulates malignant progression of colorectal cancer through Wnt signaling pathway

Tumor Biology ◽  
2017 ◽  
Vol 39 (3) ◽  
pp. 101042831769502 ◽  
Author(s):  
Taiwei Jiao ◽  
Yue Li ◽  
Tong Gao ◽  
Yining Zhang ◽  
Mingliang Feng ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Cycle ◽  
Wnt Signaling ◽  
Cell Line ◽  
Signaling Pathway ◽  
Cell Cycle Progression ◽  
Wnt Signaling Pathway ◽  
Lovo Cell ◽  
Induced Apoptosis ◽  
Cancer Tissues

MTA3 overexpression has been implicated in carcinogenesis. The aim of the present study was to explore the clinical significance and biological roles of MTA3 in human colorectal cancer and colorectal cancer cells. A total of 80 cases of colorectal cancer tissues were examined by immunohistochemistry for MTA3 protein expression. We analyzed the relationship between MTA3 and clinical factors and the results showed that MTA3 was overexpressed in 51.25% (41/80) cancer cases. There was significant associations between MTA3 overexpression and advanced TNM stage (p = 0.0086) and Ki67 index (p = 0.001). We overexpressed MTA3 in LoVo cells and depleted its expression in HCT15 cells. The results showed that MTA3 promoted cancer cell proliferation, invasion, migration, and cell cycle progression, and inhibited 5-fluorouracil-induced apoptosis in LoVo cell line. MTA3 depletion in HCT15 cell line showed the opposite effects. In addition, we found that MTA3 positively regulated cell cycle proteins including cyclin D1 and cyclin E. It also upregulated Bcl2 and downregulated Bax expression. Furthermore, we found that MTA3 could activate Wnt signaling pathway by upregulating Wnt target proteins. Our results demonstrated that MTA3 overexpression contributes to colorectal cancer carcinogenesis, progression, and chemoresistance. MTA3 could serve as a potential therapeutic target in colorectal cancer.

scholarly journals A divergent canonical WNT-signaling pathway regulates microtubule dynamics

2004 ◽  
Vol 164 (2) ◽  
pp. 243-253 ◽  
Author(s):  
Lorenza Ciani ◽  
Olga Krylova ◽  
Matthew J. Smalley ◽  
Trevor C. Dale ◽  
Patricia C. Salinas
Keyword(s):  
Wnt Signaling ◽  
Signaling Pathway ◽  
Transcriptional Activation ◽  
Glycogen Synthase ◽  
Wnt Signaling Pathway ◽  
Negative Regulator ◽  
Canonical Wnt Signaling ◽  
Microtubule Stability ◽  
Gsk 3Β ◽  
Canonical Wnt

Dishevelled (DVL) is associated with axonal microtubules and regulates microtubule stability through the inhibition of the serine/threonine kinase, glycogen synthase kinase 3β (GSK-3β). In the canonical WNT pathway, the negative regulator Axin forms a complex with β-catenin and GSK-3β, resulting in β-catenin degradation. Inhibition of GSK-3β by DVL increases β-catenin stability and TCF transcriptional activation. Here, we show that Axin associates with microtubules and unexpectedly stabilizes microtubules through DVL. In turn, DVL stabilizes microtubules by inhibiting GSK-3β through a transcription- and β-catenin–independent pathway. More importantly, axonal microtubules are stabilized after DVL localizes to axons. Increased microtubule stability is correlated with a decrease in GSK-3β–mediated phosphorylation of MAP-1B. We propose a model in which Axin, through DVL, stabilizes microtubules by inhibiting a pool of GSK-3β, resulting in local changes in the phosphorylation of cellular targets. Our data indicate a bifurcation in the so-called canonical WNT-signaling pathway to regulate microtubule stability.

scholarly journals HIV’s Nef Interacts with β-Catenin of the Wnt Signaling Pathway in HEK293 Cells

PLoS ONE ◽  
2013 ◽  
Vol 8 (10) ◽  
pp. e77865 ◽  
Author(s):  
Keren Weiser ◽  
Meredith Barton ◽  
Dafna Gershoony ◽  
Ramanuj DasGupta ◽  
Timothy Cardozo
Keyword(s):  
Wnt Signaling ◽  
Signaling Pathway ◽  
Wnt Signaling Pathway ◽  
Hek293 Cells

The effect of lentivirus-mediated SIRT1 gene knockdown in the ATDC5 cell line via inhibition of the Wnt signaling pathway

2019 ◽  
Vol 53 ◽  
pp. 80-89 ◽  
Author(s):  
Fei Yu ◽  
Yusong Yuan ◽  
Dongdong Li ◽  
Yuhui Kou ◽  
Baoguo Jiang ◽  
...  
Keyword(s):  
Wnt Signaling ◽  
Cell Line ◽  
Signaling Pathway ◽  
Wnt Signaling Pathway ◽  
Gene Knockdown ◽  
Atdc5 Cell ◽  
Sirt1 Gene

scholarly journals Activation of the Hedgehog and Wnt/β-Catenin Signaling Pathways in Basal Cell Carcinoma

2021 ◽  
pp. 506-512
Author(s):  
Tomoaki Takada
Keyword(s):  
Basal Cell Carcinoma ◽  
Wnt Signaling ◽  
Cell Carcinoma ◽  
Signaling Pathways ◽  
Signaling Pathway ◽  
Basal Cell ◽  
Transcriptional Activation ◽  
Wnt Signaling Pathway ◽  
Downstream Effectors ◽  
Mrna Binding

In basal cell carcinoma (BCC) tumorigenesis, interaction between Hedgehog (Hh) and Wnt/β-catenin (Wnt) signaling pathways has been investigated, but not completely elucidated. Here, a case of sporadic BCC in an 80-year-old man is presented, and the effectiveness of SMO inhibitors in case of relapse is predicted. The aim of this study was to determine whether the SMO inhibitors can be effective in treating this individual should the tumor recur in the future. Immunohistochemistry (IHC) was performed in a tumor and the adjacent skin tissue from the patient. IHC within the same BCC tissue specimen revealed that Glioma-associated oncogene 1 (GLI1) and Smoothened (SMO) in the Hh signaling pathway and insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) in the Wnt signaling pathway were overexpressed. Hh and Wnt signaling pathways were activated. These findings suggest that the patient might be resistant to treatment with SMO inhibitors because of the interaction between Hh and Wnt signaling pathways. Overexpression of GLI1 leads to transcriptional activation, making it an attractive molecular target for anticancer therapy owing to the downstream effectors of the cascade.

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