scholarly journals DNA Methylation of TGFβ Target Genes: Epigenetic Control of TGFβ Functional Duality in Liver Cancer

Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2207
Author(s):  
Kevin Bévant ◽  
Matthis Desoteux ◽  
Abdel Hady A. Abdel Wahab ◽  
Sabrin A. Abdel Wahab ◽  
Ayman Mohamed Metwally ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Tumor Progression ◽  
Transforming Growth Factor Beta ◽  
Epithelial To Mesenchymal Transition ◽  
Target Genes ◽  
Transforming Growth Factor ◽  
Early Stage ◽  
Potent Inducer ◽  
Mesenchymal Transition ◽  
Epigenetic Control

Transforming growth factor beta (TGFβ) plays a key role in liver carcinogenesis. However, its action is complex, since TGFβ exhibits tumor-suppressive or oncogenic properties, depending on the tumor stage. At an early stage TGFβ exhibits cytostatic features, but at a later stage it promotes cell growth and metastasis, as a potent inducer of epithelial to mesenchymal transition (EMT). Here, we evaluated DNA methylation as a possible molecular mechanism switching TGFβ activity toward tumor progression in hepatocellular carcinoma (HCC). We report that decitabine, a demethylating agent already used in the clinic for the treatment of several cancers, greatly impairs the transcriptional response of SNU449 HCC cells to TGFβ. Importantly, decitabine was shown to induce the expression of EMT-related transcription factors (e.g., SNAI1/2, ZEB1/2). We also report that the promoter of SNAI1 was hypomethylated in poor-prognosis human HCC, i.e., associated with high grade, high AFP level, metastasis and recurrence. Altogether, the data highlight an epigenetic control of several effectors of the TGFβ pathway in human HCC possibly involved in switching its action toward EMT and tumor progression. Thus, we conclude that epidrugs should be carefully evaluated for the treatment of HCC, as they may activate tumor promoting pathways.

scholarly journals Distinct functions of transforming growth factor-β signaling in c-MYC driven hepatocellular carcinoma initiation and progression

2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Haichuan Wang ◽  
Pan Wang ◽  
Meng Xu ◽  
Xinhua Song ◽  
Hong Wu ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Epithelial To Mesenchymal Transition ◽  
Target Genes ◽  
Transforming Growth Factor ◽  
Tgfβ Signaling ◽  
Genetic Event ◽  
Mesenchymal Transition

AbstractDysregulation of transforming growth factor-beta (TGFβ) signaling has been implicated in liver carcinogenesis with both tumor promoting and inhibiting activities. Activation of the c-MYC protooncogene is another critical genetic event in hepatocellular carcinoma (HCC). However, the precise functional crosstalk between c-MYC and TGFβ signaling pathways remains unclear. In the present investigation, we investigated the expression of TGFβ signaling in c-MYC amplified human HCC samples as well as the mechanisms whereby TGFβ modulates c-Myc driven hepatocarcinogenesis during initiation and progression. We found that several TGFβ target genes are overexpressed in human HCCs with c-MYC amplification. In vivo, activation of TGFβ1 impaired c-Myc murine HCC initiation, whereas inhibition of TGFβ pathway accelerated this process. In contrast, overexpression of TGFβ1 enhanced c-Myc HCC progression by promoting tumor cell metastasis. Mechanistically, activation of TGFβ promoted tumor microenvironment reprogramming rather than inducing epithelial-to-mesenchymal transition during HCC progression. Moreover, we identified PMEPA1 as a potential TGFβ1 target. Altogether, our data underline the divergent roles of TGFβ signaling during c-MYC induced HCC initiation and progression.

scholarly journals The TGFβ-induced phosphorylation and activation of p38 mitogen-activated protein kinase is mediated by MAP3K4 and MAP3K10 but not TAK1

Open Biology ◽  
2013 ◽  
Vol 3 (6) ◽  
pp. 130067 ◽  
Author(s):  
Gopal P. Sapkota
Keyword(s):  
Protein Kinase ◽  
P38 Mapk ◽  
Transforming Growth Factor Beta ◽  
Molecular Mechanisms ◽  
Epithelial To Mesenchymal Transition ◽  
Transforming Growth Factor ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Phosphorylation ◽  
Mesenchymal Transition ◽  
Mitogen Activated Protein

The signalling pathways downstream of the transforming growth factor beta (TGFβ) family of cytokines play critical roles in all aspects of cellular homeostasis. The phosphorylation and activation of p38 mitogen-activated protein kinase (MAPK) has been implicated in TGFβ-induced epithelial-to-mesenchymal transition and apoptosis. The precise molecular mechanisms by which TGFβ cytokines induce the phosphorylation and activation of p38 MAPK are unclear. In this study, I demonstrate that TGFβ-activated kinase 1 (TAK1/MAP3K7) does not play a role in the TGFβ-induced phosphorylation and activation of p38 MAPK in MEFs and HaCaT keratinocytes. Instead, RNAi -mediated depletion of MAP3K4 and MAP3K10 results in the inhibition of the TGFβ-induced p38 MAPK phosphorylation. Furthermore, the depletion of MAP3K10 from cells homozygously knocked-in with a catalytically inactive mutant of MAP3K4 completely abolishes the TGFβ-induced phosphorylation of p38 MAPK, implying that among MAP3Ks, MAP3K4 and MAP3K10 are sufficient for mediating the TGFβ-induced activation of p38 MAPK.

scholarly journals Assessing methods to quantitatively validate TGFβ-dependent autophagy

Biology Open ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. bio055103
Author(s):  
Charles B. Trelford ◽  
Gianni M. Di Guglielmo
Keyword(s):  
Cell Lines ◽  
Transforming Growth Factor Beta ◽  
Epithelial To Mesenchymal Transition ◽  
Transforming Growth Factor ◽  
Nsclc Cell ◽  
Serum Starvation ◽  
Autophagic Flux ◽  
Mesenchymal Transition ◽  
Protein Levels ◽  
Lc3 Puncta

ABSTRACTTransforming growth factor beta (TGFβ) promotes tumorigenesis by suppressing immune surveillance and inducing epithelial to mesenchymal transition (EMT). TGFβ may augment tumorigenesis by activating autophagy, which protects cancer cells from chemotherapy and promotes invasive and anti-apoptotic properties. Here, we assess how TGFβ1 modulates autophagy related (ATG) gene expression and ATG protein levels. We also assessed microtubule-associated protein light chain 3 (LC3) lipidation, LC3 puncta formation and autophagosome-lysosome co-localization in non-small cell lung cancer (NSCLC) cell lines. These experimental approaches were validated using pharmacological autophagy inhibitors (chloroquine and spautin-1) and an autophagy activator (MG132). We found that TGFβ1, chloroquine and MG132 had little effect on ATG protein levels but increased LC3 lipidation, LC3 puncta formation and autophagosome-lysosome co-localization. Since similar outcomes were observed using chloroquine and MG132, we concluded that several techniques employed to assess TGFβ-dependent autophagy may not differentiate between the activation of autophagy versus lysosomal inhibition. Thus, NSCLC cell lines stably expressing a GFP-LC3-RFP-LC3ΔG autophagic flux probe were used to assess TGFβ-mediated autophagy. Using this approach, we observed that TGFβ, MG132 and serum starvation increased autophagic flux, whereas chloroquine and spautin-1 decreased autophagic flux. Finally, we demonstrated that ATG5 and ATG7 are critical for TGFβ-dependent autophagy in NSCLC cells. The application of this model will fuel future experiments to characterize TGFβ-dependent autophagy, which is necessary to understand the molecular processes that link, TGFβ, autophagy and tumorigenesis.

scholarly journals Loss of BRMS1 Promotes a Mesenchymal Phenotype through NF-κB-Dependent Regulation ofTwist1

2014 ◽  
Vol 35 (1) ◽  
pp. 303-317 ◽  
Author(s):  
Yuan Liu ◽  
Marty W. Mayo ◽  
Aizhen Xiao ◽  
Emily H. Hall ◽  
Elianna B. Amin ◽  
...  
Keyword(s):  
Transforming Growth Factor Beta ◽  
Cancer Metastasis ◽  
Epithelial To Mesenchymal Transition ◽  
Transforming Growth Factor ◽  
Breast Cancer Metastasis ◽  
Metastasis Suppressor ◽  
Mesenchymal Phenotype ◽  
Mesenchymal Transition ◽  
Metastasis Suppressor 1 ◽  
Promoter Occupancy

Breast cancer metastasis suppressor 1 (BRMS1) is downregulated in non-small cell lung cancer (NSCLC), and its reduction correlates with disease progression. Herein, we investigate the mechanisms through which loss of theBRMS1gene contributes to epithelial-to-mesenchymal transition (EMT). Using a short hairpin RNA (shRNA) system, we show that loss of BRMS1 promotes basal and transforming growth factor beta-induced EMT in NSCLC cells. NSCLC cells expressingBRMS1shRNAs (BRMS1knockdown [BRMS1KD]) display mesenchymal characteristics, including enhanced cell migration and differential regulation of the EMT markers. Mesenchymal phenotypes observed inBRMS1KDcells are dependent on RelA/p65, the transcriptionally active subunit of nuclear factor kappa B (NF-κB). In addition, chromatin immunoprecipitation analysis demonstrates that loss ofBRMS1increasesTwist1promoter occupancy of RelA/p65 K310—a key histone modification associated with increased transcription. Knockdown ofTwist1results in reversal ofBRMS1KD-mediated EMT phenotypic changes. Moreover, in our animal model,BRMS1KD/Twist1KDdouble knockdown cells were less efficient in establishing lung tumors thanBRMS1KDcells. Collectively, this study demonstrates that loss of BRMS1 promotes malignant phenotypes that are dependent on NF-κB-dependent regulation ofTwist1. These observations offer fresh insight into the mechanisms through which BRMS1 regulates the development of metastases in NSCLC.

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