CEMIP induces TGF-β/Smad signaling to promote keloid development by binding to SPARC.

BACKGROUND

Cell Migration Inducing Hyaluronidase 1 (CEMIP) is a protein that plays regulatory functions in a variety of cellular processes in many diseases. Nevertheless, its role and molecular mechanism in keloid hyperplasia are still elusive.

METHODS

Expressions of CEMIP and Secreted Protein acidic and Rich in Cysteine (SPARC) were detected by qRT-PCR and western blot. CCK-8 assay, along with immunofluorescence staining, was applied for the assessment of cell proliferation. The capabilities of cells to migrate and invade were evaluated utilizing wound healing and Transwell, while Extracellular Matrix (ECM) deposition was measured by immunofluorescence and western blot. The interaction of CEMIP and SPARC was predicted by the Coexpedia and PPA-red databases and verified by co-IP. Western blot was adopted for the estimation of TGF-β/Smad pathway-related proteins.

RESULTS

The data demonstrated that CEMIP expression was elevated in Keloid Fibroblasts (KF). CEMIP interference suppressed cell proliferative, migrative and invasive capabilities and ECM deposition in KF. Mechanistically, bioinformatics analysis revealed that CEMIP was co-expressed with SPARC and CEMIP protein could bind to SPARC. SPARC expression was reduced in CEMIP-silenced cells. SPARC overexpression counteracted the impacts of CEMIP silencing on cell proliferative, migrative and invasive capabilities and ECM deposition in KF. In addition, the expressions of TGF-β/Smad signaling-related proteins were decreased by CEMIP silencing via the inhibition of SPARC.

CONCLUSION

In summary, this study revealed that CEMIP modulated KF proliferation, migration, invasion and ECM deposition by TGF-β/Smad signaling through binding to SPARC.