title: Significance of oral cancer-associated fibroblasts in angiogenesis, lymphangiogenesis, and tumor invasion in oral squamous cell carcinoma.
abstract: BACKGROUND
  Cancer-associated fibroblasts (CAFs) are recognized as a pivotal promoter in cancer initiation and development. However, the role of CAFs in the progression and metastasis of oral squamous cell carcinoma (OSCC) has not been fully elucidated.
  
  
  METHODS
  Lymphatic vessel density (LVD) and microvessel density (MVD) and the expression of α-smooth muscle actin (α-SMA) and matrix metalloproteinase-9 (MMP-9) were evaluated by immunohistochemistry in 86 cases of OSCC. The correlations between α-SMA expression and MMP-9 expression, LVD, MVD, and other clinicopathological parameters were analyzed. In vitro invasion assay was performed to assess the effect of CAFs on the invasion of OSCC cells. We also investigated the effect of CAFs on the angiogenesis and lymphangiogenesis by inoculating CAFs with OSCC cells into nude mice subcutaneously.
  
  
  RESULTS
  Positive expression of α-SMA protein was detected in 69.8% of the tumors. Increased α-SMA expression was correlated strongly with enhanced tumor invasion, higher tumor grade, increased risk of recurrence, lymph node involvement, and higher peritumoral lymphatic vessel density and microvessel density (P < 0.05). CAFs induced more cancer cells to invade relative to normal fibroblasts (NFs) (P < 0.05). Compared with co-injection of OSCC cells and NFs or injection of tumor cells alone, co-injection of OSCC cells and CAFs resulted in earlier tumor formation and bigger tumor volume accompanied with increased angiogenesis and lymphangiogenesis (P < 0.05).
  
  
  CONCLUSIONS
  CAFs may play critical roles in OSCC progression as an inducer of tumor invasion, angiogenesis, and lymphangiogenesis. Therapeutic strategies targeting CAFs against OSCC is promising and need further exploration.
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Nan-Nan
authors.initials: NN
authors.lastname: Lin
authors.affiliation: Department of Stomatology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhao
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Fu-Jun
authors.initials: FJ
authors.lastname: Zhang
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Yang
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Chen
mesh_terms: D000199:Actins / Q000378:metabolism*; D000818:Animals; D000072645:Cancer-Associated Fibroblasts / Q000502:physiology*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000503:physiopathology; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D006801:Humans; D007150:Immunohistochemistry; D042583:Lymphangiogenesis; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D008819:Mice, Nude; D009062:Mouth Neoplasms / Q000378:metabolism* / Q000503:physiopathology; D009361:Neoplasm Invasiveness; D009389:Neovascularization, Pathologic
chemical_list: D000199:Actins; C544013:alpha-smooth muscle actin, mouse; D020780:Matrix Metalloproteinase 9; C501830:Mmp9 protein, mouse
keywords: angiogenesis; cancer-associated fibroblasts; lymphangiogenesis; matrix metalloproteinase-9; oral squamous cell carcinoma