Exposure to TNF‑α combined with TGF‑β induces carcinogenesis in vitro via NF-κB/Twist axis

  • Authors:
    • Weilei Dong
    • Shuwen Sun
    • Xiaocheng Cao
    • Yinghong Cui
    • A. Chen
    • Xiang Li
    • Jiansong Zhang
    • Jianguo Cao
    • Yifeng Wang
  • View Affiliations

  • Published online on: January 16, 2017     https://doi.org/10.3892/or.2017.5369
  • Pages: 1873-1882
Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )
Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )


Abstract

Persistent human papilloma virus (HPV) infection induces chronic inflammation resulting in human cervical cancer. However, the mechanisms underlying carcinogenesis via chronic inflammation remain largely unclear. We investigated the role of pro-inflammatory factors in epithelial-mesenchymal transition (EMT) and cancer stem cell-like (CSCL) characteristics of HeLa cells exposed to TNF‑α with or without TGF‑β. We then determined the role of NF-κB/Twist signal axis in the pathogenesis of cervical cancer. We found that HeLa cells exposed to TNF‑α following chronic treatment with TGF‑β exhibited EMT, self-renewal and high mobility. Knockdown of NF-κBp65 inhibited NF-κB and Twist1 expression, and EMT and CSCL properties of HeLa cells following co-treatment with TNF‑α and TGF‑β. Conversely, overexpression of NF-κBp65 potentiated the above effects. However, knockdown or overexpression of Twist1 had no effect on NF-κBp65 expression, but inhibited or promoted EMT and CSCL features. Notably, overexpression of Twist1 rescued NF-κBp65 knockdown. Our results demonstrate the role of NF-κB/Twist signaling axis in which HeLa cells treated with TNF‑α following chronic exposure to TGF‑β induce EMT and CSCL properties. The NF-κB/Twist signal axis may represent an effective therapeutic target in cervical cancer.

Introduction

Cervical cancer is a key factor associated with morbidity and mortality in women worldwide (1). Infection with human papilloma viruses (HPV) triggers carcinogenesis. Most of the precancerous lesions do not progress to invasive carcinoma, suggesting that HPV is not the only factor contributing to the development of cervical cancer (2,3). However, persistent HPV infection alters the pro-inflammatory cytokine profile, resulting in chronic inflammation and recurrence of cervical cancer (4). Cancer stem cells (CSCs) play a vital role in cancer initiation and metastasis (5). Metastasis results in treatment failure and death (6). Epithelial-mesenchymal transition (EMT) has been implicated as the key factor in CSCs transformation (7,8). EMT has been shown to induce reversion to a CSC-like phenotype, linking CSCs and EMT (9,10).

NF-κB is a classic transcription factor activated by inflammatory stimuli, such as LPS (11), TNF-α (12) and IL-10 (13). Activated NF-κB induces extensive gene expression in immune response (TNF-α), angiogenesis (VEGF), invasion (MMP-9) and EMT (Twist) (1417). Furthermore, NF-κB, a pleiotropic transcription factor, has been implicated in EMT and metastasis (1417). In mammary epithelial cells, EMT is upregulated via overexpression of NF-κBp65 (17).

The transcriptional factor TWIST mediates EMT and cancer metastasis (18,19). In uterine cancers, Twist overexpression promotes invasion and metastasis (2023). However, the role of NF-κB/Twist axis in cervical cancer has not been investigated. In this study, we focused on the role of NF-κB/Twist axis in vitro, by co-treatment of human cervical cancer cell line HeLa with TNF-α and TGF-β.

Materials and methods

Reagents

DMEM was obtained from Gibco, FBS from PAA, trypsin and penicillin-streptomycin from Invitrogen, and TGF-β and TNF-α from Sino Biological (Beijing, China). Anti-E-cadherin and anti-N-cadherin antibodies were supplied by Cell Signaling Technology (Danvers, MA, USA). The following antibodies were purchased from Abcam (Burlingame, CA, USA): anti-Bmi1, anti-Sox2, anti-Oct4, anti-CD133, anti-CD44, anti-ALDH1, anti-NF-κBp65 and anti-Twist1.

Cell culture and EMT morphology

HeLa cells were supplied by the Cell Bank of Chinese Academy of Sciences (Shanghai, China), and cultured as described by López et al (5). Cells were incubated with TNF-α (10.0 ng/ml) for 24 h, TGF-β (5.0 ng/ml) for 6 days or TNF-α (10.0 ng/ml) for 24 h along with TGF-β (5.0 ng/ml) for 6 days. EMT morphology were visualized under a light microscope (Olympus, Japan). The regulation of gene expression was studied by transducing cells with either NF-κBp65 shRNA and Twist1 shRNA or NF-κBp65 and Twist1-carrying adenoviruses obtained from Hanbio Biothechnology Co. Ltd. (1.0 ml, 1×1011 pfu/ml; Shanghai, China).

Wound healing assay

Wound healing was tested by loading cells (5×105) in 6-well plates and grown until cells attained 90% confluence. A scratch was created using a 100-µl pipette tip and rinsed with PBS. Photographs were obtained and analyzed at 24 h, and the migrating cell number was standardized with mock.

Sphere formation

Cells (1,000 cells/ml) were loaded on ultra-low attachment 24-well culture plates (Corning, USA) in stem cell conditional medium. Five days later, the number of spheroids in each well was scored. The sphere formation rate was calculated as a percentage of the total number of spheres among the viable cells.

Western blot analysis

Whole cell lysates were prepared as previously described (24). The primary antibodies used for membrane incubation were as follows: anti-E-cadherin, anti-N-cadherin, anti-Bmi1, anti-Sox2, anti-Oct4, anti-CD133, anti-CD44, anti-ALDH1, anti-NF-κB and anti-Twist. The membranes were further incubated with anti-mouse or anti-rabbit secondary antibodies conjugated to horseradish peroxidase (HRP). After incubation, the specific protein bands were visualized by enhanced chemiluminescence, using β-actin as a loading control.

Statistical analysis

Experimental data were analyzed using SPSS 20.0 for Windows (SPSS Inc, Chicago, IL, USA). Data representing mean ± SD were subjected to one-way ANOVA. First, the homogeneity of variance was determined. We used LSD to analyze pairwise comparisons among the groups. In the event of incomplete variance, the control and the experimental groups were analyzed with Tukey's test. A probability of <0.05 suggested statistical significance.

Results

Treatment with TNF-α or TGF-β or both induces EMT and CSCL properties in HeLa cells and increases NF-κB and Twist levels

TNF-α induces proliferation of epithelial tumor cells following exposure to TGF-β and EMT (17,19). Morphological features ranging from cobblestone appearance to spindle phenotypes were observed in HeLa cells after exposure to pro-inflammatory cytokines TGF-β (5.0 ng/ml) or TNF-α (10.0 ng/ml) or both (Fig. 1A). Western blot analysis results were validated using antibodies targeting EMT-related markers. As shown in Fig. 1B, the pro-inflammatory cytokines downregulated E-cadherin and upregulated N-cadherin expression. Concurrently, we measured the cell migration and self-renewal after treatment with the inflammatory cytokines. The results showed that the combination of pro-inflammatory cytokines enhanced migration (Fig. 1C) and self-renewal (Fig. 1D) of HeLa cells. The multipotent stem cell factors Bmi1, Sox2 and Oct4 were overexpressed (Fig. 1E). Similarly, the stem cell markers CD133, CD44 and ALDH1 were upregulated (Fig. 1F). NF-κB is a key regulator of inflammation, and Twist plays an important role in EMT (17,25,26). As illustrated in Fig. 1G, Western blots revealed an overexpression of NF-κB and Twist1 in HeLa cells after treatment with the different cytokines, either alone or in combination.

In this preliminary experiment, the characteristic EMT phenotype was apparent in HeLa cells exposed to TNF-α alone for 24 h, and combined with TGF-β for 6 days (data not shown).

Silencing of NF-κBp65 downregulates Twist and reverses EMT and CSCL features in HeLa cells exposed to inflammatory cytokines

The expression of NF-κBp65 and Twist in shNF-κBp65-expressing HeLa cells exposed to TGF-β and TNF-α was significantly lower than in the control cells (Fig. 2A). EMT morphological changes and relevant protein expression were detected. As shown in Fig. 2B and C, NF-κBp65 shRNA-expressing HeLa cells exhibited cobble-stone-like morphology, while GFP control cells displayed spindle shape. Furthermore, NF-κBp65 shRNA-expressing HeLa cells expressed higher levels of E-cadherin in epithelial cells, and a lower level of N-cadherin. The wound healing and sphere formation assays revealed that silencing of NF-κBp65 expression in HeLa cells decreased migration and self-renewal following co-treatment with TNF-α and TGF-β (Fig. 2D and E). Furthermore, compared with control cells, knockdown of NF-κBp65 expression reduced the expression of multi-functional proteins Bmi1, Sox2 and Oct4 (Fig. 2F), while CSC surface markers CD133, CD44 and ALDH1 (Fig. 2G) were induced by co-treatment with TNF-α and chronic exposure to TGF-β.

Overexpression of NF-κBp65 upregulates Twist and promotes EMT and CSCL properties in HeLa cells exposed to inflammatory cytokines

We evaluated the effect of overexpression of NF-κBp65 on EMT and CSCL properties of HeLa cells exposed to TNF-α and TGF-β. NF-κBp65-expressing adenovirus-infected HeLa cells overexpressed NF-κBp65 and Twist1 (Fig. 3A). As illustrated in Fig. 3B and C, increased expression of mesenchymal marker N-cadherin and decreased expression of epithelial marker E-cadherin and spindle shape were found in NF-κBp65-expressing HeLa cells. These findings suggested that NF-κB mediated a significant switch from epithelial to mesenchymal phenotypes in HeLa cells following exposure to TNF-α and TGF-β. As shown in Fig. 3D and E, NF-κBp65 overexpression results in increased cell migration and self-renewal in HeLa cells. Furthermore, we found that NF-κBp65 expression modulated Bmi1, Sox2, Oct4 (Fig. 3F), and CD133, CD44 and ALDH1 (Fig. 3G) in HeLa cells exposed to proinflammatory cytokines.

Knockdown of Twist1 has no effect on NF-κB expression but reverses the EMT and CSCL properties in HeLa cells

To elucidate the relationship between NF-κB and Twist1 in HeLa cells, shTwist1-expressing adenovirus was used to infect HeLa cells following exposure to TNF-α and TGF-β. Compared with GFP-expressing HeLa cells, the knockdown of Twist1 downregulated the expression of Twist1 but not the expression of NF-κBp65 (Fig. 4A). Twist1 knockdown resulted in cobble-stone-like cells (Fig. 4B). The expression of E-cadherin was significantly upregulated while the mesenchymal marker N-cadherin was downregulated (Fig. 4C). Further, Twist1 silencing attenuated the migration and self-renewal of HeLa cells exposed to TNF-α and TGF-β (Fig. 4D and E). Furthermore, Twist1 knockdown downregulated cancer stem-related multi-functional proteins Bmi1, Sox2 and Oct4 (Fig. 4F) and surface markers CD133, CD44 and ALDH1 in HeLa cells following co-treatment with TNF-α and TGF-β (Fig. 4G).

Overexpression of Twist1 promoted EMT and CSCL properties of HeLa cells exposed to TNF-α and TGF-β

Overexpression of Twist1 was not accompanied by NF-κBp65 protein expression (Fig. 5A). As shown in Fig. 5B and C, Twist1-expressing adenovirus infected HeLa cells overexpressing mesenchymal marker N-cadherin and downregulated the epithelial marker E-cadherin. Furthermore, overexpression of Twist1 increased cell migration (Fig. 5D) and high sphere formation rate (Fig. 5E). Twist1 regulated the expression of Bmi1, Sox2, and Oct4 (Fig. 5F), and CD133, CD44 and ALDH1 (Fig. 5G) in HeLa cells following co-treatment with TNF-α and TGF-β.

Twist1 transduction rescues NF-κB knockdown-related inhibition of Twist1 expression, and EMT and CSCL properties in HeLa cells exposed to inflammatory cytokines

To elucidate the role of NF-κB/Twist axis in EMT and CSCL properties of HeLa cells exposed to inflammatory cytokines, we transducted Twist1 into NF-κBp65-silenced HeLa cells. As shown in Fig. 6A, NF-κBp65 shRNA downregulated NF-κBp65 and Twist protein expression. Transduction of Twist1 upregulated the levels of Twist without affecting the NF-κBp65 profile. Interestingly, Twist1 gene transduction restored NF-κBp65 shRNA-downregulated Twist expression. The shNF-κBp65-expressing HeLa cells overexpressed epithelial markers E-cadherin and downregulated mesenchymal marker N-cadherin. Under these conditions, Twist1 gene transduction did not inhibit NF-κBp65, but rescued shNF-κBp65 downregulation of Twist 1 expression (Fig. 6B and C). Similarly, Twist1 gene transduction rescued the inhibitory effects of shNF-κBp65 on migration (Fig. 6E) and self-renewal (Fig. 6F) and cancer stem cell-related protein expression (Fig. 6G) in HeLa cells following exposure to TNF-α and TGF-β.

Discussion

Chronic inflammation-induced carcinogenesis and metastasis is a major challenge to cancer therapy, and is a key factor contributing to mortality in many malignancies (1117). Understanding the mechanisms regulating the metastasis and carcinogenesis induced by pro-inflammatory cytokines may lead to novel therapeutic interventions (17). In this study, we demonstrated that pro-inflammatory TNF-α and TGF-β synergistically induced EMT and CSCL properties in HeLa cells via NF-κB/Twist axis. We characterized the biological role of NF-κB and Twist1 in EMT and cell migration, self-renewal and stem cell marker expression. We demonstrated the role of NF-κB/Twist1 signal axis in HeLa cells induced by exposure to TNF-α and TGF-β. Various studies suggest that TNF-α induces a variety of epithelial cells and epithelial tumor cell EMT morphology following chronic exposure to TGF-β (17). In this study, we constructed a chronic inflammation model, by co-treatment with TNF-α and TGF-β to induce EMT phenotype in HeLa cells. Further, the exposure to pro-inflammatory cytokines also leads to cell migration and self-renewal, and CSC-related protein expression. NF-κBp65 knockdown or overexpression therefore, alters Twist1 protein expression. However, Twist1 knockdown or overexpression has no effects on NF-κBp65 expression. The results provide convinced evidence supporting NF-κB location upstream of Twist1. Finally, we demonstrated the role of NF-κB/Twist axis, using Twist and shNF-κBp65 co-transduction rescue assay. The results show that Twist1 overexpression almost reversed all the biological effects of shNF-κBp65.

An increasing number of studies have shown that EMT plays a decisive role in tumorigenesis, including local infiltration and metastasis and spread through the circulatory system (26). We monitored the cell morphology and the expression of EMT-related proteins E-cadherin and N-cadherin to determine the phenotype variation. E-cadherin triggers epithelial intercellular adhesion. Cells devoid of E-cadherin show increased N-cadherin expression (27). In this study, the role of NF-κB/Twist signal axis in EMT phenotype acquisition by HeLa cells was examined, and their overexpression promoted EMT.

Migration and CSL properties increase the risk of malignant tumor metastasis (2830). Therefore, we investigated these phenomena along the NF-κB/Twist axis, using scratch assay and sphere formation to detect migration and self-renewal. NF-κB/Twist overexpression promotes HeLa cell migration and self renewal. Similarly, NF-κB/Twist overexpression upregulates the levels of CSC proteins Bmi1, Sox2 and Oct4 and CSC surface proteins CD133, CD44, and ALDH1.

In conclusion, our results provide insight into the mechanism of TNF-α-induced EMT and CSCL properties of HeLa cells chronically exposed to TGF-β, and demonstrate that these effects are mediated via NF-κB/Twist axis. Targeting NF-κB/Twist axis is a potential treatment strategy to improve prognosis in patients with cervical cancer.

Acknowledgements

This study was supported by the Projects of NSFC (nos. 30760248, 81172375 and 31400311), the Project of Scientific Research Fund of Hunan Provincial Education Department (no. 14C0707), the Project of Hunan Provincial Natural Science Foundation (no. 13JJ3061) and the Scientific Research Fund of Hunan Normal University (nos. 140668 and 140666).

Glossary

Abbreviations

Abbreviations:

CSCL

cancer stem cell-like

CSCs

cancer stem cells

EMT

epithelial-mesenchymal transition

HPV

persistent human papilloma virus

HRP

horseradish peroxidase

References

1 

Diaz-Padilla I, Monk BJ, Mackay HJ and Oaknin A: Treatment of metastatic cervical cancer: Future directions involving targeted agents. Crit Rev Oncol Hematol. 85:303–314. 2013. View Article : Google Scholar : PubMed/NCBI

2 

Erickson BK, Landers EE and Huh WK: Update on vaccination clinical trials for HPV-related disease. Clin Ther. 36:8–16. 2014. View Article : Google Scholar : PubMed/NCBI

3 

Murata T, Mizushima H, Chinen I, Moribe H, Yagi S, Hoffman RM, Kimura T, Yoshino K, Ueda Y, Enomoto T, et al: HB-EGF and PDGF mediate reciprocal interactions of carcinoma cells with cancer-associated fibroblasts to support progression of uterine cervical cancers. Cancer Res. 71:6633–6642. 2011. View Article : Google Scholar : PubMed/NCBI

4 

Egawa N, Egawa K, Griffin H and Doorbar J: Human papillomaviruses; epithelial tropisms, and the development of neoplasia. Viruses. 7:3863–3890. 2015. View Article : Google Scholar : PubMed/NCBI

5 

López J, Poitevin A, Mendoza-Martínez V, Pérez-Plasencia C and García-Carrancá A: Cancer-initiating cells derived from established cervical cell lines exhibit stem-cell markers and increased radioresistance. BMC Cancer. 12:482012. View Article : Google Scholar : PubMed/NCBI

6 

Iglesias M, Plowman GD and Woodworth CD: Interleukin-6 and interleukin-6 soluble receptor regulate proliferation of normal, human papillomavirus-immortalized, and carcinoma-derived cervical cells in vitro. Am J Pathol. 146:944–952. 1995.PubMed/NCBI

7 

Lin J, Liu X and Ding D: Evidence for epithelial-mesenchymal transition in cancer stem-like cells derived from carcinoma cell lines of the cervix uteri. Int J Clin Exp Pathol. 8:847–855. 2015.PubMed/NCBI

8 

Liu X, Wang D, Liu H, Feng Y, Zhu T, Zhang L, Zhu B and Zhang Y: Knockdown of astrocyte elevated gene-1 (AEG-1) in cervical cancer cells decreases their invasiveness, epithelial to mesenchymal transition, and chemoresistance. Cell Cycle. 13:1702–1707. 2014. View Article : Google Scholar : PubMed/NCBI

9 

Mani SA, Guo W, Liao MJ, Eaton EN, Ayyanan A, Zhou AY, Brooks M, Reinhard F, Zhang CC, Shipitsin M, et al: The epithelial-mesenchymal transition generates cells with properties of stem cells. Cell. 133:704–715. 2008. View Article : Google Scholar : PubMed/NCBI

10 

Polyak K and Weinberg RA: Transitions between epithelial and mesenchymal states: Acquisition of malignant and stem cell traits. Nat Rev Cancer. 9:265–273. 2009. View Article : Google Scholar : PubMed/NCBI

11 

Zhang X, Li N, Shao H, Meng Y, Wang L, Wu Q, Ioa Y, Li J, Bian J, Zhang Y, et al: Methane limit LPS-induced NF-κB/MAPKs signal in macrophages and suppress immune response in mice by enhancing PI3K/AKT/GSK-3β-mediated IL-10 expression. Sci Rep. 6:293592016. View Article : Google Scholar : PubMed/NCBI

12 

Chen PJ, Wang YL, Kuo LM, Lin CF, Chen CY, Tsai YF, Shen JJ and Hwang TL: Honokiol suppresses TNF-α-induced neutrophil adhesion on cerebral endothelial cells by disrupting polyubiquitination and degradation of IκBα. Sci Rep. 6:265542016. View Article : Google Scholar : PubMed/NCBI

13 

Hu X, Han C, Jin J, Qin K, Zhang H, Li T, Li N and Cao X: Integrin CD11b attenuates colitis by strengthening Src-Akt pathway to polarize anti-inflammatory IL-10 expression. Sci Rep. 6:262522016. View Article : Google Scholar : PubMed/NCBI

14 

Ramasamy S, Saez B, Mukhopadhyay S, Ding D, Ahmed AM, Chen X, Pucci F, Yamin R, Wang J, Pittet MJ, et al: Tle1 tumor suppressor negatively regulates inflammation in vivo and modulates NF-κB inflammatory pathway. Proc Natl Acad Sci USA. 113:1871–1876. 2016. View Article : Google Scholar : PubMed/NCBI

15 

Mariani F, Sena P and Roncucci L: Inflammatory pathways in the early steps of colorectal cancer development. World J Gastroenterol. 20:9716–9731. 2014. View Article : Google Scholar : PubMed/NCBI

16 

Korkaya H, Liu S and Wicha MS: Regulation of cancer stem cells by cytokine networks: Attacking cancer's inflammatory roots. Clin Cancer Res. 17:6125–6129. 2011. View Article : Google Scholar : PubMed/NCBI

17 

Li CW, Xia W, Huo L, Lim SO, Wu Y, Hsu JL, Chao CH, Yamaguchi H, Yang NK, Ding Q, et al: Epithelial-mesenchymal transition induced by TNF-α requires NF-κB-mediated transcriptional upregulation of Twist1. Cancer Res. 72:1290–1300. 2012. View Article : Google Scholar : PubMed/NCBI

18 

Yang J, Mani SA, Donaher JL, Ramaswamy S, Itzykson RA, Come C, Savagner P, Gitelman I, Richardson A and Weinberg RA: Twist, a master regulator of morphogenesis, plays an essential role in tumor metastasis. Cell. 117:927–939. 2004. View Article : Google Scholar : PubMed/NCBI

19 

Wang Y, Liu J, Ying X, Lin PC and Zhou BP: Twist-mediated epithelial-mesenchymal transition promotes breast tumor cell invasion via inhibition of hippo pathway. Sci Rep. 6:246062016. View Article : Google Scholar : PubMed/NCBI

20 

Fan Q, Qiu MT, Zhu Z, Zhou JH, Chen L, Zhou Y, Gu W, Wang LH, Li ZN, Xu Y, et al: Twist induces epithelial-mesenchymal transition in cervical carcinogenesis by regulating the TGF-β/Smad3 signaling pathway. Oncol Rep. 34:1787–1794. 2015.PubMed/NCBI

21 

Wushou A, Hou J, Zhao YJ and Shao ZM: Twist-1 up-regulation in carcinoma correlates to poor survival. Int J Mol Sci. 15:21621–21630. 2014. View Article : Google Scholar : PubMed/NCBI

22 

Wang T, Li Y, Tuerhanjiang A, Wang W, Wu Z, Yuan M and Wang S: Correlation of Twist upregulation and senescence bypass during the progression and metastasis of cervical cancer. Front Med. 8:106–112. 2014. View Article : Google Scholar : PubMed/NCBI

23 

Zhu K, Chen L, Han X and Wang J and Wang J: Short hairpin RNA targeting Twist1 suppresses cell proliferation and improves chemosensitivity to cisplatin in HeLa human cervical cancer cells. Oncol Rep. 27:1027–1034. 2012.PubMed/NCBI

24 

Li J and Zhou BP: Activation of β-catenin and Akt pathways by Twist are critical for the maintenance of EMT associated cancer stem cell-like characters. BMC Cancer. 11:492011. View Article : Google Scholar : PubMed/NCBI

25 

Li XW, Tuergan M and Abulizi G: Expression of MAPK1 in cervical cancer and effect of MAPK1 gene silencing on epithelial-mesenchymal transition, invasion and metastasis. Asian Pac J Trop Med. 8:937–943. 2015. View Article : Google Scholar : PubMed/NCBI

26 

Lim W, Kim HE, Kim Y, Na R, Li X, Jeon S, Choi H and Kim O: Association between cancer stem cell-like properties and epithelial-to-mesenchymal transition in primary and secondary cancer cells. Int J Oncol. 49:991–1000. 2016.PubMed/NCBI

27 

Cao X, Ren K, Song Z, Li D, Quan M, Zheng Y, Cao J, Zeng W and Zou H: 7-Difluoromethoxyl-5,4′-di-n-octyl genistein inhibits the stem-like characteristics of gastric cancer stem-like cells and reverses the phenotype of epithelial-mesenchymal transition in gastric cancer cells. Oncol Rep. 36:1157–1165. 2016.PubMed/NCBI

28 

Choudhary KS, Rohatgi N, Halldorsson S, Briem E, Gudjonsson T, Gudmundsson S and Rolfsson O: EGFR signal-network reconstruction demonstrates metabolic crosstalk in EMT. PLOS Comput Biol. 12:e10049242016. View Article : Google Scholar : PubMed/NCBI

29 

Moirangthem A, Bondhopadhyay B, Mukherjee M, Bandyopadhyay A, Mukherjee N, Konar K, Bhattacharya S and Basu A: Simultaneous knockdown of uPA and MMP9 can reduce breast cancer progression by increasing cell-cell adhesion and modulating EMT genes. Sci Rep. 6:219032016. View Article : Google Scholar : PubMed/NCBI

30 

Kong L, Guo S, Liu C, Zhao Y, Feng C, Liu Y, Wang T and Li C: Overexpression of SDF-1 activates the NF-κB pathway to induce epithelial to mesenchymal transition and cancer stem cell-like phenotypes of breast cancer cells. Int J Oncol. 48:1085–1094. 2016.PubMed/NCBI

Related Articles

Journal Cover

March-2017
Volume 37 Issue 3

Print ISSN: 1021-335X
Online ISSN:1791-2431

Sign up for eToc alerts

Recommend to Library

Copy and paste a formatted citation
x
Spandidos Publications style
Dong W, Sun S, Cao X, Cui Y, Chen A, Li X, Zhang J, Cao J and Wang Y: Exposure to TNF‑α combined with TGF‑β induces carcinogenesis in vitro via NF-κB/Twist axis. Oncol Rep 37: 1873-1882, 2017
APA
Dong, W., Sun, S., Cao, X., Cui, Y., Chen, A., Li, X. ... Wang, Y. (2017). Exposure to TNF‑α combined with TGF‑β induces carcinogenesis in vitro via NF-κB/Twist axis. Oncology Reports, 37, 1873-1882. https://doi.org/10.3892/or.2017.5369
MLA
Dong, W., Sun, S., Cao, X., Cui, Y., Chen, A., Li, X., Zhang, J., Cao, J., Wang, Y."Exposure to TNF‑α combined with TGF‑β induces carcinogenesis in vitro via NF-κB/Twist axis". Oncology Reports 37.3 (2017): 1873-1882.
Chicago
Dong, W., Sun, S., Cao, X., Cui, Y., Chen, A., Li, X., Zhang, J., Cao, J., Wang, Y."Exposure to TNF‑α combined with TGF‑β induces carcinogenesis in vitro via NF-κB/Twist axis". Oncology Reports 37, no. 3 (2017): 1873-1882. https://doi.org/10.3892/or.2017.5369