OBJECTIVE: To probe into the effects of chlorogenic acid（CGA） on proliferation and apoptosis of laryngeal cancer Hep-2 cells through Bcl-2-associated X protein（Bax）/B cell lymphoma-2（Bcl-2）/cysteinyl aspartate specific proteinase-3（Caspase-3）. METHODS: Laryngeal cancer Hep-2 cells were treated with CGA culture medium of 0

250

500

750 and 1 000 μmol/L for 24 and 48 h respectively to find out the most suitable concentration and treatment time of CGA. Laryngeal cancer Hep-2 cells were divided into the control group（normally cultured laryngeal cancer Hep-2 cells）

CGA low concentration group（750 μmol/L CGA medium）

CGA high concentration group（1 000 μmol/L CGA medium）

and CGA high concentration+pathway inhibitor group（1 000 μmol/L CGA medium+50 μmol/L Bax/Bcl-2/Caspase-3 pathway inhibitor Bax inhibitor peptide V5）. Cell counting kit-8（CCK-8） method was used to determine the proliferation inhibition rate of laryngeal cancer Hep-2 cells in each group

flow cytometry was used to detect the apoptosis rate of laryngeal cancer Hep-2 cells in each group

Western blotting was used to determine the expression of proliferation related protein（ki-67）

apoptosis related protein（p53） and Bax/Bcl-2/Caspase-3 signaling pathway related proteins in laryngeal cancer Hep-2 cells. RESULTS: Compared with the control group

the proliferation inhibition rate

apoptosis rate

p53

Bax and Caspase-3 protein expression levels of laryngeal cancer Hep-2 cells in CGA low and high concentration group were significantly higher

and the ki-67 and Bcl-2 protein expression levels were significantly lower

with statistically significant differences（P<0.05）; and the proliferation inhibition rate

apoptosis rate

p53

Bax and Caspase-3 protein expression levels of laryngeal cancer Hep-2 cells in CGA high concentration group were higher than those in CGA low concentration group

the of ki-67 and Bcl-2 protein expression levels were lower than those in CGA low concentration group

with statistically significant differences（P<0.05）. Compared with the CGA high concentration group

the proliferation inhibition rate

apoptosis rate

p53

Bax and Caspase-3 protein expression levels of laryngeal cancer Hep-2 cells in the CGA high concentration+pathway inhibitor group were significantly lower

and the ki-67 and Bcl-2 protein expression levels were significantly higher

with statistically significant differences（P<0.05）. CONCLUSIONS: CGA can significantly inhibit the proliferation of laryngeal cancer Hep-2 cells and promote the apoptosis

which may be related to the activation of Bax/Bcl-2/Caspase-3 signaling pathway.