Ovarian cancer is one of the most common causes of female mortalities from gynecological
tumors. An ent‑kaurane
diterpenoid compound CRT1 (ent‑18‑acetoxy‑7β‑hydroxy kaur‑15‑oxo‑16‑ene), mainly isolated from the Vietnamese herb Croton tonkinesis has been used in
folk medicine in Vietnam for
cancer treatment. However, the effect of this compound on human
ovarian cancer cells has not yet been reported. The objective of the present study was to determine the effect of CRT1 on the cell viability, apoptosis and
metastasis of SKOV3 human
ovarian cancer cells using a Cell Counting Kit‑8 assay, flow cytometric analysis of
Annexin V‑fluorescein
isothiocyanate/
propidium iodide staining, western blot analysis, soft
agar colony forming assay, wound healing assay and
Matrigel invasion assay. The results revealed that CRT1 possessed significant anti‑proliferative effects on SKOV3 cells. CRT1 treatment at 25 and 50 µM induced apoptosis, enhanced the percentage of
Annexin V‑positive cells, increased the expression of pro‑apoptotic
protein B‑cell
lymphoma 2 (Bcl‑2)‑associated X
protein,
cytochrome c release from the mitochondria to the cytosol, cleaved caspase‑3, caspase‑7, caspase‑9, and poly (
adenosine diphosphate‑ribose) polymerase. However, it decreased the expression of Bcl‑2 in a dose‑dependent manner. The percentage of necrotic cells increased following CRT1 treatment at <10 µM. CRT1 at 50 µM significantly induced the phosphorylation of extracellular signal‑regulated
kinase (ERK). Growth inhibition and the apoptotic effects of CRT1 could be reversed by
PD98059, an ERK inhibitor. Additionally, CRT1 inhibited cell migration and invasion via ERK1/2 activation in SKOV3 cells. These results indicated that CRT1, an ent‑kaurane
diterpenoid, may be a potential inhibitor of
ovarian cancer by the activating ERK1/2/
p90 ribosomal S6 kinase signaling pathway.