[Effect of Echinococcus granulosus cyst fluid on the proliferation of HepG2 cells].

Objective: To investigate whether Echinococcus granulosus cyst fluid-infected host liver cells had differential expression of mitogen-activated protein kinases (MAPKs) or differential cell cycle activity.

Methods: Human liver cells cultured with different concentrations of hydatid cyst fluid (HCF) were tested by the MTT method to determine effects on proliferation. The cell cycle was assessed by flow cytometry. Western blotting was used to detect changes in protein expressions of p-ERK, PCNA, cyclin-A, cyclin-B1, cyclin-D1, and cyclin-E.

Results: Forty-eight, 72 and 96 h of HCF at 15%, 30% and 60% concentrations in the cell media significantly promoted cell proliferation (F=67.845, P less than 0.01) and compared to controls (P less than 0.05). Cells exposed to 15% HCF for 48 h showed significantly induced expression of p-ERK (F=1.916, P less than 0.01), higher than controls (P less than 0.01). Cells exposed to 15% HCF for 24 h showed significantly induced expression of cyclin-Dl (F=3.901, P less than 0.01), higher than controls (P less than 0.01). Cells exposed to 15% HCF for 48 h or 30% HCF for 72 h showed significantly induced expression of PCNA (F=91.140, P less than 0.01), higher than controls (P less than 0.01). Cells exposed to 15% HCF for 48 h or 30% HCF for 72 h shed significantly induced expression of cyclin-A (F=18.587, P=0.002), higher than controls (P less than 0.01). Cells exposed to 15% HCF for either 48 h or 72 h showed significantly induced expression of cyclin-B1 (F=2.064, P less than 0.01), higher than controls (P less than 0.01). Cells exposed to 30% HCF for 96 h showed significantly induced expression of cyclin-E (F=1.068, P less than 0.01), higher than controls (P less than 0.01).

Conclusion: Hydatid cyst fluid exerts no inhibitory effect on primary cultured host liver cells, but may promote cellular proliferation.