Effects of SAHA on proliferation and apoptosis of hepatocellular carcinoma cells and hepatitis B virus replication.

AIM

To investigate the effects of suberoylanilide hydroxamic acid (SAHA) on proliferation and apoptosis of a human hepatocellular carcinoma cell line (HepG2.2.15) and hepatitis B virus (HBV) replication.

METHODS

HepG2.2.15 cells were treated with different concentrations of SAHA. Cell morphology was examined by confocal laser scanning microscopy, and cell proliferation was determined using a MTT colorimetric assay. Flow cytometry was used to detect apoptosis and determine cell cycle phase, while hepatitis B surface antigen and hepatitis B e antigen content were measured using chemiluminescence. Reverse transcription polymerase chain reaction was performed to measure HBV DNA in cell lysate.

RESULTS

Cell proliferation rates were significantly reduced by the addition of SAHA. The inhibitory effect of SAHA on cell proliferation was both time- and dose-dependent. After 24 h of treatment with SAHA, the early cell apoptotic rate increased from 3.25% to 21.02% (P = 0.041). The proportion of G₀/G₁ phase cells increased from 50.3% to 65.3% (P = 0.039), while that of S phase cells decreased from 34.9% to 20.6% (P = 0.049). After 48 h of treatment, hepatitis B surface antigen and hepatitis B e antigen content increased from 12.33 ± 0.62 to 25.42 ± 2.67 (P = 0.020) and 28.92 ± 1.24 to 50.48 ± 1.85 (P = 0.026), respectively. Furthermore, HBV DNA content increased from 4.54 ± 0.46 to 8.34 ± 0.59 (P = 0.029).

CONCLUSION

SAHA inhibits HepG2.2.15 cell proliferation, promotes apoptosis, and stimulates HBV replication. In combination with anti-HBV drugs, SAHA may potentially be used cautiously for treatment of hepatocellular carcinoma.