TUSC3 inhibits cell proliferation and invasion in cervical squamous cell carcinoma via suppression of the AKT signaling pathway
Abstract Background The expression of tumor suppressor candidate 3 (TUSC3) is associated with proliferation in several types of cancer, leading to an unfavorable prognosis. The present study aimed to assess the cellular and molecular function of TUSC3 in patients with cervical squamous cell carcinoma (CSCC). Methods Levels of mRNA expressions of TUSC3 were analyzed in CSCC tissues and six cell lines using qRT-PCR. Immunohistochemistry(IHC) was used to evaluate the protein expression level of TUSC3 in four paired specimens, 220 paraffin-embedded CSCC specimens and 60 cases of normal cervical tissues(NCTs), respectively. Short hairpin RNA interference was employed for TUSC3 knockdown. Cell proliferation, migration and invasion was evaluated using growth curve, MTT assay, wound healing and transwell assay respectively. Results The results demonstrated that TUSC3 mRNA and protein expression levels were down-regulated in CSCC samples. Multivariate and univariate analyses indicated that TUSC3 was an independent prognostic factor for patients with CSCC. Decreased TUSC3 expression levels were significantly associated with proliferation and an aggressive phenotype of cervical cancer cells. Moreover, the knockdown of TUSC3 promoted migration and invasion of cancer cells, while the increased expression of TUSC3 exhibited the opposite effects. The down-regulation of TUSC3 facilitated proliferation and invasion of CSCC cells through the activation of the AKT signaling pathway. Conclusions Our data demonstrated that the down-regulation of TUSC3 promoted CSCC cell metastasis via the AKT signaling pathway. Therefore, TUSC3 may serve as a novel prognostic marker and potential target for CSCC.