pPeOp from Omphalia lapidescens Schroet suppresses the proliferation of cervical cancer HeLa cells via JAK/STAT3 signaling pathway

pPeOp is a protein extracted from the sclerotium of Omphalia lapidescens. Several studies have shown its anti-carcinogenic effects. However, its functions in cervical cancer and the underlying cellular mechanisms are relatively unknown. Here, we examined the effect and molecular mechanism of pPeOp on HeLa cells. The MTS assay and EdU assay showed that pPeOp decreased Hela cell viability and proliferation in a dose-dependent manner. Besides, the quantitative real-time PCR (qRT-PCR) and western blot analysis showed that the mRNA levels of JAK1, JAK2, GP130, and STAT3 and protein levels of STAT3 and p-STAT3 were significantly decreased, whereas the mRNA expression levels of SOCS1 and SOCS3 were significantly elevated in HeLa cells. Furthermore, Interleukin-6 (IL-6) and NSC74859 were used as the agonist and inhibitor of the JAK/STAT3 signaling pathway, respectively. The flow cytometry and MTS assay showed that the antitumor effect was increased when pPeOp was co-treated with IL-6, while decreased with inhibitor treatment. These results demonstrate that pPeOp could effectively inhibit the proliferation and viability of cervical cancer cells by regulating JAK/STAT3 signaling pathway, suggesting that pPeOp may serve as a novel therapeutic agent for cervical cancer.