PP2A Inhibits Cervical Cancer Cell Migration by Dephosphorylation of p-JNK, p-p38 and the p-ERK/MAPK Signaling Pathway.

ABSTRACT

Protein phosphatase 2A (PP2A) was reported to play an important role in cancer development; however, the relationship between PP2A and cervical cancer development has yet to be fully understood. The present study aimed to explore the role of PP2A in the development of cervical cancer. Serum levels of PP2A were detected by ELISA in 23 patients with cervical cancer and 30 patients with benign cervical lesions. Furthermore, the PP2A activities and the mRNA and protein levels of PP2A were measured in cervical cancer (n=8) and chronic cervicitis (n=10) tissues. The results showed that the serum levels of PP2A were significantly reduced in patients with cervical cancer. Further studies showed that not only the activities of PP2A but also the mRNA and protein levels of PP2A were significantly decreased in cervical cancer tissues. Wound healing and Transwell assays demonstrated that pharmacological and genetic upregulation of PP2A could inhibit the migration of HeLa cells, but the downregulation of PP2A promoted cellular migration. The activation of PP2A also inhibited the remodeling of actin and the activity of mitogen-activated protein kinases (MAPKs) including p-JNK, p-p38 and p-ERK. Meanwhile, the activation of PP2A was found to downregulate MMP-9 levels, which further inhibited the migration and invasion of HeLa cells. In conclusion, our data suggest that the activity and expression of PP2A are significantly reduced in cervical cancer tissues, and the activation of PP2A may inhibit the migration of cervical cancer cells by inhibiting the phosphorylation of p-JNK, p-p38 and the p-ERK/MAPK signaling pathway as well as by downregulating MMP-9, implying that PP2A plays an important role in cervical cancer development.