Invasion of uterine cervical squamous cell carcinoma cells is facilitated by locoregional interaction with cancer-associated fibroblasts via activating transforming growth factor-beta

Gynecol Oncol. 2015 Jan;136(1):104-11. doi: 10.1016/j.ygyno.2014.11.075. Epub 2014 Nov 28.

Abstract

Objective: Local invasion is a common pattern of spread in uterine cervical squamous cell carcinoma (CSCC). Although transforming growth factor-beta (TGF-β) facilitates invasion of various types of cancer cells, the role of the TGF-β pathway in CSCC is unclear. In this study, we analyzed the role of TGF-β signaling in the progression of CSCC.

Methods: Immunohistochemistry was used to examine the expression of TGF-β pathway molecules in 67 CSCC samples with clinicopathological data. Activation of the TGF-β pathway was investigated following co-culture of CSCC cells and cervical cancer-associated fibroblasts (CCAFs).

Results: Clinicopathological analysis of CSCC samples revealed that prominent expression of TGF-β receptor-2 was more frequent in CSCC with lymphovascular space invasion (LVSI) than without LVSI (p < 0.01). Lymph node metastasis was more frequent in cases in which phosphorylated SMAD3 (pSMAD3) was localized exclusively at the boundary of tumor clusters (n = 9, p < 0.05). Recombinant TGF-β1 increased pSMAD3 expression and enhanced cellular invasion (p < 0.005) in CSCC cells, which was attenuated by an inhibitor of the TGF-β receptor (p < 0.005). Enhanced pSMAD3 expression and invasion was also observed when conditioned media from CSCC cells co-cultured with CCAFs were administered. Luciferase assays showed that this medium contained a large amount of active TGF-β. Along with TGF-β activation, thrombospondin-1 was upregulated in both CSCC cells and CCAFs, while thrombospondin-1 silencing in either CSCC cells or CCAFs repressed the activity of TGF-β. Thrombospondin-1 was prominently expressed in cases with pSMAD3 boundary staining (p < 0.05).

Conclusions: These results suggest that interaction between CSCC cells and surrounding CCAFs activates TGF-β via thrombospondin-1 secretion to facilitate CSCC invasion.

Keywords: Cancer associated fibroblasts; Cervical cancer; Invasion; TGF-beta.

MeSH terms

  • Carcinoma, Squamous Cell / metabolism
  • Carcinoma, Squamous Cell / pathology*
  • Cell Communication / physiology*
  • Female
  • Fibroblasts / metabolism
  • Fibroblasts / pathology*
  • Humans
  • Middle Aged
  • Neoplasm Invasiveness
  • Neoplasm Staging
  • Signal Transduction
  • Transforming Growth Factor beta / metabolism*
  • Uterine Cervical Neoplasms / metabolism
  • Uterine Cervical Neoplasms / pathology*

Substances

  • Transforming Growth Factor beta