EFEMP1 in Direct Inguinal Hernia: correlation with TIMP3 and Regulation Toward Elastin Homoeostasis as Well as Fibroblast Mobility.

AIM

This basic research aimed to detect the inner-correlation of EGF containing fibulin extracellular matrix protein 1 (EFEMP1), TIMP metallopeptidase inhibitor 3 (TIMP3), matrix metalloprotease 9 (MMP9), elastin (ELN) in direct inguinal hernia (IH), and their effect on fibroblasts motility.

METHODS

Transversalis fascia samples from 20 direct IH patients and 20 varicocele (served as controls) patients were collected for detecting EFEMP1, TIMP3, MMP9 and ELN expressions by immunohistochemistry assay. Fibroblasts L929 cells were transfected with EFEMP1 overexpression plasmid or knock-down plasmid to investigate the influence of EFEMP1 dysregulation on L929 cell migration, invasion, TIMP3, MMP9 and ELN expressions. Additionally, rescue experiments were performed by adding TIMP3 knockdown plasmid to the EFEMP1-overexpressed L929 cells.

RESULTS

Transversalis fascia EFEMP1, TIMP3 and ELN expressions were decreased, but MMP9 expression was increased in IH patients compared with controls. In IH patients, EFEMP1 was not correlated with TIMP3, but positively correlated with ELN and negatively correlated with MMP9; TIMP3 negatively correlated with MMP9, but positively correlated with ELN. Overexpression of EFEMP1 did not affect TIMP3 expression but increased ELN expression and decreased MMP9 expression in L929 cells. In addition, EFEMP1 suppressed L929 cell migration and invasion. The following rescue experiments indicated that silencing TIMP3 attenuated the effect of EFEMP1 overexpression on MMP9 and ELN expressions as well as the effect of EFEMP1 overexpression on cell migration and invasion in L929 cells.

CONCLUSIONS

EFEMP1 is downregulated in direct IH, and it regulates ELN homoeostasis as well as fibroblast mobility via interacting with TIMP3.