Ursolic Acid Induced Apoptosis Involving Upregulation of Expression of PTEN Gene and Inactivation of PI3K/Akt Pathway in K562 Cells

Ursolic acid(UA), a pentacyclic triterpenoid derived from many kinds of medicinal plants, exhibits potent anticancer activity in many kinds of cancer cells. However, the anticancer mechanism of UA is not clearly understood.

The toxic action of UA in K562 cells was assessed using CCK-8. K562 cells trested by UA were incubated with FITC-conjugated Annexin V and counterstained with PI in order to allow exclusion of necrotic cells, then were subsequently analyzed using a flow cytometer. Pro-caspase-3, cleaved caspase-3, Procaspase-9, cleaved caspase-9, Akt and Akt phosphorylation were analyzed by Western Blotting. The expression of PTEN gene is analyzed by Quantitative real-time RT-PCR.

Here we showed that UA could cause growth inhibition, and induce apoptosis in human chronic myelogenous leukemia cell line K562 cells. The expression of PTEN gene is rejected in many kinds of cancers including leukemia, then the PI3K/Akt pathway is actived. So the PTEN gene and PI3K/Akt pathway become the central targer for cancer therapy. UA treatment can up-regulate the expression of PTEN gene, inhibite the activity of Akt kinase, change the mitochondrial transmembrane potential, then induce the reduce of cytochrome C and the active of caspase family.

These results suggest that UA might exhibit its strong antitumor effects via the up-regulation of PTEN gene and the inhibited the activity of PI3K/Akt pathway.

No relevant conflicts of interest to declare.