Myosin 1b promotes cell proliferation, migration, and invasion in cervical cancer

Recent evidence suggests an important role of Myosin 1b (Myo1b) in the progression of several cancers, including prostate cancer and head and neck squamous cell carcinoma (HNSCC). However, the contribution of Myo1b to cervical cancer (CC) remains elusive.

Quantitative reverse transcription polymerase chain reaction (qRT-PCR), immunohistochemistry and western blotting assays were used to confirm the expression of Myo1b in CC tissues compared with matched non-tumor tissues and CC cells, and analyze its clinical significance. In vitro, RNA interference (siRNA or shRNA) was used to investigate the biological function and underlying mechanism of Myo1b in cervical carcinogenesis. Furthermore, tumor growth was evaluated in vivo using a xenogenous subcutaneously implant model.

Here, for the first time we reported that Myo1b expression was significantly increased in human CC, compared to cervical intraepithelial neoplasia (CIN) and normal cervical tissues and that the upregulation of Myo1b was significantly correlated with FIGO Stage, HPV infection, lymph node metastasis and pathological grade. In vitro, knockdown of Myo1b significantly suppressed proliferation, migration, and invasion of CaSki and SiHa cells, and markedly decreased the MMP1/MMP9 activities. Also, silencing the expression of Myo1b dramatically repressed tumor growth in a mouse xenograft model. Further investigations showed that HPV16 E6 or E7 could enhance the expression of Myo1b via upregulating c-MYC.

Taken together, our data suggested a potential role of Myo1b in cervical carcinogenesis and tumor progression and provided novel insights into the mechanism of how this factor promotes cell proliferation, migration, and invasion in CC cells.