Effects of RNAi-mediated Smad4 silencing on growth and apoptosis of human rhabdomyosarcoma cells

Lv, Ye; Zhang, Hongying; Zhang, Li; Yang, Guanghua; Qin, Ke; Guo, Hua; Bu, Hong

doi:10.3892/ijo.29.5.1149

Cited by 9 publications

(11 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A simultaneous knockdown of Smad2, Smad3 and Smad4 proteins in human HaCaT keratinocyte cells, affected TGF-b-dependent responses in invasion, wound healing and apoptosis (Jazag et al, 2005). RNAi-mediated Smad4 silencing suppressed growth significantly and induced apoptosis of human rhabdomyosarcoma cells (Ye et al, 2006). A knockdown of Smad4 in MDA-MB-231 breast cancer cells, using shRNA-expressing vectors inhibited bone metastasis in nude mice and increased survival (Deckers et al, 2006).…”

Section: Discussionmentioning

confidence: 99%

Microglia-derived TGF-β as an important regulator of glioblastoma invasion—an inhibition of TGF-β-dependent effects by shRNA against human TGF-β type II receptor

et al. 2007

View full text Add to dashboard Cite

The invasion of tumor cells into brain tissue is a pathologic hallmark of malignant gliomas and contributes to treatment failures. Diffuse glioblastomas contain numerous microglial cells, which enhance the progression of gliomas; however, factors responsible for invasionpromoting role of microglia are unknown. Transforming growth factor-b (TGF-b) can enhance tumor growth, invasion, angiogenesis and immunosuppression. Antagonizing TGF-b activity has been shown to inhibit tumor invasion in vitro and tumorigenicity, but a systemic inhibition or lack of TGF-b signaling results in acute inflammation and disruption of immune system homeostasis. We developed plasmid-transcribed small hairpin RNAs (shRNAs) to downregulate the TGF-b type II receptor (TbIIR) expression, which effectively inhibited cytokine-induced signaling pathways and transcriptional responses in transiently transfected human glioblastoma cells. Silencing of TbIIR abolished TGF-b-induced glioblastoma invasiveness and migratory responses in vitro. Moreover, tumorigenicity of glioblastoma cells stably expressing TbIIR shRNAs in nude mice was reduced by 50%. Microglia strongly enhanced glioma invasiveness in the co-culture system, but this invasion-promoting activity was lost in glioma cells stably expressing shTbRII, indicating a crucial role of microglia-derived TGF-b in tumor-host interactions. Our results demonstrate a successful targeting of TGF-b-dependent invasiveness and tumorigenicity of glioblastoma cells by RNAi-mediated gene silencing.

show abstract

Section: Discussionmentioning

confidence: 99%

Microglia-derived TGF-β as an important regulator of glioblastoma invasion—an inhibition of TGF-β-dependent effects by shRNA against human TGF-β type II receptor

et al. 2007

View full text Add to dashboard Cite

show abstract

“…Smad4-siRNA Reverses EMT in Hepatocytes in Vitro-To demonstrate the central role of the TGF-␤1/Smad signal on EMT induction, siRNA technology was used for smad4 gene silencing in both primary and AML12 hepatocytes (24,25). The efficiency of siRNA transfection and resultant smad4 gene silencing in primary and AML12 hepatocytes was evaluated by IP, qRT-PCR, and IF.…”

Section: Tgf-␤1 Induces Snail-1 and Smad4 Activation In Hepatocytes-smentioning

confidence: 99%

Transforming Growth Factor-β1 Induces an Epithelial-to-Mesenchymal Transition State in Mouse Hepatocytes in Vitro

Kaimori

Potter

Kaimori

et al. 2007

Journal of Biological Chemistry

330

271

View full text Add to dashboard Cite

Liver fibrosis is a progressive pathologic process that involves deposition of excess extracellular matrix leading to distorted architecture and culminating in cirrhosis. The role of transforming growth factor-␤ (TGF-␤) as a key molecule in the development and progression of hepatic fibrosis via the activation of hepatic stellate cells, among other fibroblast populations, is without controversy. We hereby show that TGF-␤1 induces an epithelial-to-mesenchymal transition (EMT) state in mature hepatocytes in vitro. EMT state was marked by significant upregulation of ␣ 1 (I) collagen mRNA expression and type I collagen deposition. Similar changes were found in a "normal" mouse hepatocyte cell line (AML12), thus confirming that hepatocytes are capable of EMT changes and type I collagen synthesis. We also show that in hepatocytes in the EMT state, TGF-␤1 induces the snail-1 transcription factor and activates the Smad2/3 pathway. Evidence for a central role of the TGF-␤1/Smad pathway is further supported by the inhibition of EMT by Smad4 silencing using small interference RNA technology. In conclusion, TGF-␤1, a known pro-apoptotic cytokine in mature hepatocytes, is capable of mediating phenotypic changes and plasticity in the form of EMT, resulting in collagen deposition. Our findings support a potentially crucial role for EMT in the development and progression of hepatic fibrogenesis.Liver fibrosis results from increased deposition of type I collagen within the hepatic extracellular space and constitutes a common cardinal signature to all forms of liver injury, regardless of etiology (1). End-stage liver fibrosis is recognized clinically as cirrhosis. Since their initial description, hepatic stellate cells (HSC) 3 have dominated the field of liver fibrogenesis (2-4). Indeed, their role is central in hepatic fibrosis (5). Unfortunately, despite several discoveries pertaining to HSC activation and mechanisms of collagen deposition, no substantial anti-fibrotic therapies have been developed in order to halt the progression to cirrhosis and or reverse established fibrosis. Although resident tissue fibroblasts are traditionally considered as the principal source of fibrosis, there has been increasing interest in the ability of epithelial cells to assume not only a mesenchymal phenotype (known as epithelial-to-mesenchymal transition (EMT)) but also to undertake mesenchymal function(s), i.e. contribute to fibrosis formation. Indeed, EMT has been established as a major mechanism for the deposition of extracellular matrix in renal and pulmonary fibrosis injury models (6 -8).Several lines of evidence support an important role for TGF-␤1 signaling in the initiation and progression of liver fibrosis (9). In mature (i.e. adult) hepatocytes, TGF-␤1 is responsible for inhibition of cell proliferation and induction of apoptosis (10 -12). Interestingly, TGF-␤1 is the most established mediator and regulator of EMT (13). It has been shown that TGF-␤1 mediates EMT by inducing snail-1 transcription factor and tyrosine phosphorylation o...

show abstract

“…Moreover, TGF-β1 treatment can partially counteract the effect of Smad4 shRNA in growth inhibition and apoptosis induction [9] . All of these findings suggest that the TGF-β1/Smad4 signaling pathway plays very important roles in RMS tumorigenesis and progression, and as such, may be a good target for RMS therapy.…”

Section: Discussionmentioning

confidence: 99%

“…A previous study showed that cells of the human ERMS cell line RD exhibit autocrine TGF-β1 signaling and overexpress TβR-I, TβR-II and the downstream Smads 2, 3 and 4 [8] . Importantly, exogenous TGF-β1 can partially counteract the effect of Smad4 knockdown by RNA interference [9] . These results suggest that TGF-β1 may be a novel therapeutic target for RMS treatment.…”

mentioning

confidence: 99%

Inhibitory Effects of Resveratrol on the Human Alveolar Rhabdomyosarcoma Cell Line PLA-802 through Inhibition of the TGF-β1/Smad Signaling Pathway

Yang

Yuan²,

Luo

et al. 2016

Pharmacology

View full text Add to dashboard Cite

While anti-tumor activity of resveratrol has been demonstrated for many cancers, little is known about its effects on soft tissue sarcoma. Overexpression of TGF-β1, a protein inhibited by resveratrol, is a well-known feature of the rhabdomyosarcoma (RMS), a type of soft tissue sarcoma. In the present study, we examined the effects of resveratrol on the human alveolar RMS (ARMS) cell line PLA-802. Cultured PLA-802 cells were treated with different concentrations of resveratrol at distinct time points and changes in their growth, cell cycle progression and TGF-β1 signaling were assessed. MTT assay showed a decrease in the viability of PLA-802 cells treated with resveratrol (p < 0.05). Cell cycle analysis using flow cytometry revealed that resveratrol induced a significant decrease in the number of cells in S phase and an increase in the number of cells in G1 phase (p < 0.05). Furthermore, expression of TGF-β1 and its downstream factor Smad4 mRNA and protein, assessed by RT-PCR and Western blot, were inhibited by resveratrol in a concentration- and time-dependent manner. Immunofluorescent staining results confirmed these changes in expression and showed that co-localization of TGF-β1 with Smad4 was gradually decreased by resveratrol. Together, our results suggest that resveratrol may inhibit cell proliferation and cell cycle progression in PLA-802 cells through inhibiting activity of the TGF-β1 signaling pathway. Our findings highlight the therapeutic potential of resveratrol for suppressing the tumorigenicity of human ARMS.

show abstract

Effects of RNAi-mediated Smad4 silencing on growth and apoptosis of human rhabdomyosarcoma cells

Cited by 9 publications

References 38 publications

Microglia-derived TGF-β as an important regulator of glioblastoma invasion—an inhibition of TGF-β-dependent effects by shRNA against human TGF-β type II receptor

Microglia-derived TGF-β as an important regulator of glioblastoma invasion—an inhibition of TGF-β-dependent effects by shRNA against human TGF-β type II receptor

Transforming Growth Factor-β1 Induces an Epithelial-to-Mesenchymal Transition State in Mouse Hepatocytes in Vitro

Inhibitory Effects of Resveratrol on the Human Alveolar Rhabdomyosarcoma Cell Line PLA-802 through Inhibition of the TGF-β1/Smad Signaling Pathway

Contact Info

Product

Resources

About