Skip to main content

Advertisement

SpringerLink
Log in

mTOR regulates TGF-β2-induced epithelial–mesenchymal transition in cultured human lens epithelial cells

  • Basic Science
  • Published:
Graefe's Archive for Clinical and Experimental Ophthalmology Aims and scope Submit manuscript

Abstract

Background

Post-cataract surgery fibrosis in the lens capsule is caused by epithelial to mesenchymal transition (EMT) of the lens epithelium. Mammalian target of rapamycin (mTOR) has been demonstrated to be a key regulator of EMT. The aim of this study was to investigate the role of mTOR in transforming growth factor β2 (TGF-β2)-induced EMT in human lens epithelial cells (HLECs).

Methods

Human lens epithelial B-3 (HLEB-3) cells were cultured with 10 ng/ml TGF-β2 for different periods of time. The expression of E-cadherin, connexin 43, fibronectin and α-smooth muscle actin (α-SMA), and activation of mTOR were determined by Western blots. Cell migration was assessed by wound healing assay. An inhibition test was performed using two kinds of mTOR inhibitors.

Results

E-cadherin and connexin 43 expressions were suppressed, whereas fibronectin and α-SMA expressions were increased in HLEB-3 cells after treatment with TGF-β2. mTOR was activated during the TGF-β2-induced EMT in a time-dependent manner. Rapamycin or Ku-0063794 with 100 nM was able to inhibit the phosphorylation of mTOR and impaired EMT induced by TGF-β2. Cell motility enhanced by TGF-β2 for 24 h was attenuated by both rapamycin and Ku-0063794.

Conclusions

mTOR is activated during TGF-β2-induced EMT in HLECs, suggesting that it is involved in the regulation of TGF-β2-induced EMT and may contribute to the development of posterior capsule opacification.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  1. Pandey SK, Apple DJ, Werner L, Maloof AJ, Milverton EJ (2004) Posterior capsule opacification: a review of the aetiopathogenesis, experimental and clinical studies and factors for prevention. Indian J Ophthalmol 52:99–112

    PubMed  Google Scholar 

  2. Awasthi N, Guo S, Wagner BJ (2009) Posterior capsular opacification: a problem reduced but not yet eradicated. Arch Ophthalmol 127:555–562

    Article  PubMed  Google Scholar 

  3. Kalluri R, Weinberg RA (2009) The basics of epithelial–mesenchymal transition. J Clin Invest 119:1420–1428

    Article  PubMed  CAS  Google Scholar 

  4. Xu J, Lamouille S, Derynck R (2009) TGF-beta-induced epithelial to mesenchymal transition. Cell Res 19:156–172

    Article  PubMed  CAS  Google Scholar 

  5. Dawes LJ, Elliott RM, Reddan JR, Wormstone YM, Wormstone IM (2007) Oligonucleotide microarray analysis of human lens epithelial cells: TGFbeta regulated gene expression. Mol Vis 13:1181–1197

    PubMed  CAS  Google Scholar 

  6. Yao K, Ye PP, Tan J, Tang XJ, Shen Tu XC (2008) Involvement of PI3K/Akt pathway in TGF-beta2-mediated epithelial mesenchymal transition in human lens epithelial cells. Ophthalmic Res 40:69–76

    Article  PubMed  CAS  Google Scholar 

  7. de Iongh RU, Wederell E, Lovicu FJ, McAvoy JW (2005) Transforming growth factor-beta-induced epithelial–mesenchymal transition in the lens: a model for cataract formation. Cells Tissues Organs 179:43–55

    Article  PubMed  Google Scholar 

  8. Laplante M, Sabatini DM (2009) mTOR signaling at a glance. J Cell Sci 122:3589–3594

    Article  PubMed  CAS  Google Scholar 

  9. Jacinto E, Loewith R, Schmidt A, Lin S, Rüegg MA, Hall A, Hall MN (2004) Mammalian TOR complex 2 controls the actin cytoskeleton and is rapamycin insensitive. Nat Cell Biol 6:1122–1128

    Article  PubMed  CAS  Google Scholar 

  10. Shorning BY, Griffiths D, Clarke AR (2011) Lkb1 and Pten synergise to suppress mTOR-mediated tumorigenesis and epithelial–mesenchymal transition in the mouse bladder. PLoS One 6:e16209

    Article  PubMed  CAS  Google Scholar 

  11. Gulhati P, Bowen KA, Liu J, Stevens PD, Rychahou PG, Chen M, Lee EY, Weiss HL, O’Connor KL, Gao T, Evers BM (2011) mTORC1 and mTORC2 regulate EMT, motility, and metastasis of colorectal cancer via RhoA and Rac1 signaling pathways. Cancer Res 71:3246–3256

    Article  PubMed  CAS  Google Scholar 

  12. Liu H, Feng G, Wu L, Fu S, Liu P, Yang W, Zhang X (2010) The effects of rapamycin on lens epithelial cell proliferation, migration, and matrix formation: an in vitro study. Mol Vis 16:1646–1653

    PubMed  CAS  Google Scholar 

  13. Liu H, Wu L, Fu S, Hou Y, Liu P, Cui H, Liu J, Xing L, Zhang X (2009) Polylactide-glycoli acid and rapamycin coating intraocular lens prevent posterior capsular opacification in rabbit eyes. Graefes Arch Clin Exp Ophthalmol 247:801–807

    Article  PubMed  CAS  Google Scholar 

  14. Saika S, Yamanaka O, Flanders KC, Okada Y, Miyamoto T, Sumioka T, Shirai K, Kitano A, Miyazaki K, Tanaka S, Ikeda K (2008) Epithelial–mesenchymal transition as a therapeutic target for prevention of ocular tissue fibrosis. Endocr Metab Immune Disord Drug Targets 8:69–76

    Article  PubMed  CAS  Google Scholar 

  15. Lovicu FJ, Ang S, Chorazyczewska M, McAvoy JW (2004) Deregulation of lens epithelial cell proliferation and differentiation during the development of TGFbeta-induced anterior subcapsular cataract. Dev Neurosci 26:446–455

    Article  PubMed  CAS  Google Scholar 

  16. Dwivedi DJ, Pino G, Banh A, Nathu Z, Howchin D, Margetts P, Sivak JG, West-Mays JA (2006) Matrix metalloproteinase inhibitors suppress transforming growth factor-beta-induced subcapsular cataract formation. Am J Pathol 168:69–79

    Article  PubMed  CAS  Google Scholar 

  17. Harris TJ, Tepass U (2010) Adherens junctions: from molecules to morphogenesis. Nat Rev Mol Cell Biol 11:502–514

    Article  PubMed  CAS  Google Scholar 

  18. Peinado H, Olmeda D, Cano A (2007) Snail, Zeb and bHLH factors in tumour progression: an alliance against the epithelial phenotype? Nat Rev Cancer 7:415–428

    Article  PubMed  CAS  Google Scholar 

  19. Wong RC, Dottori M, Koh KL, Nguyen LT, Pera MF, Pébay A (2006) Gap junctions modulate apoptosis and colony growth of human embryonic stem cells maintained in a serum-free system. Biochem Biophys Res Commun 344:181–188

    Article  PubMed  CAS  Google Scholar 

  20. Lovicu FJ, Steven P, Saika S, McAvoy JW (2004) Aberrant lens fiber differentiation in anterior subcapsular cataract formation: a process dependent on reduced levels of Pax6. Invest Ophthalmol Vis Sci 45:1946–1953

    Article  PubMed  Google Scholar 

  21. Hay N, Sonenberg N (2004) Upstream and downstream of mTOR. Genes Dev 18:1926–1945

    Article  PubMed  CAS  Google Scholar 

  22. Derynck R, Zhang YE (2003) Smad-dependent and Smad-independent pathways in TGF-beta family signaling. Nature 425:577–584

    Article  PubMed  CAS  Google Scholar 

  23. Bakin AV, Tomlinson AK, Bhowmick NA, Moses HL, Arteaga CL (2000) Phosphatidylinositol 3-kinase function is required for transforming growth factor beta-mediated epithelial to mesenchymal transition and cell migration. J Biol Chem 275:36803–36810

    Article  PubMed  CAS  Google Scholar 

  24. Lamouille S, Derynck R (2007) Cell size and invasion in TGF-beta-induced epithelial to mesenchymal transition is regulated by activation of the mTOR pathway. J Cell Biol 178:437–451

    Article  PubMed  CAS  Google Scholar 

  25. García-Martínez JM, Moran J, Clarke RG, Gray A, Cosulich SC, Chresta CM, Alessi DR (2009) Ku-0063794 is a specific inhibitor of the mammalian target of rapamycin (mTOR). Biochem J 421:29–42

    Article  PubMed  Google Scholar 

Download references

Grant

This study is supported by the Fund for Guangzhou Pearl River Nova of Science and Technology (2011J2200050) and Guangdong Natural Science (S2011010000462).

Financial disclosure(s)

We declare no financial support or financial conflict of interest.

Author information

Authors and Affiliations

  1. Guangdong Eye Institute, Department of Ophthalmology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou, 510080, Guangdong, People’s Republic of China

    Qianli Meng, Haike Guo, Lijia Xiao, Ying Cui, Rui Guo & Yu Huang

  2. Research Center of Medicine, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou, 510080, Guangdong, People’s Republic of China

    Dingzhang Xiao

Authors
  1. Qianli Meng
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Haike Guo
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Lijia Xiao
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Ying Cui
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Rui Guo
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Dingzhang Xiao
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Yu Huang
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Haike Guo.

Additional information

The authors have full control of all primary data, and we agree to allow Graefe’s Archive for Clinical and Experimental Ophthalmology to review our data upon request.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Meng, Q., Guo, H., Xiao, L. et al. mTOR regulates TGF-β2-induced epithelial–mesenchymal transition in cultured human lens epithelial cells. Graefes Arch Clin Exp Ophthalmol 251, 2363–2370 (2013). https://doi.org/10.1007/s00417-013-2435-z

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00417-013-2435-z

Keywords

Search

Navigation