Tra2? Silencing Suppresses Cell Proliferation In Laryngeal Squamous Cell Carcinoma Via Inhibiting PI3K/AKT Signaling

ObjectiveTransformer-2 protein homolog beta(Tra2?)generally plays an important role in various human cancers,but its role and the underlying mechanisms in laryngeal squamous cell carcinoma(LSCC)remained unknown.This study aimed to assess the clinical significance and regulatory mechanisms of Tra2? in LSCC.Methods and Materials Part one1.We used immunohistochemistry analyses to analyze the expression of Tra2?in laryngeal cell carcinoma tissues.And SPSS19.0 software was used to analyze the correlation between Tra2? and clinic pathological characteristic in LSCC patients,which includes patients' age,gender,clinical stage,histological grade,metastasis and so on.And we analyzed the expression of Tra2? in LSCC tissues and paired adjacent healthy tissues using q RT-PCR methods.2.The survival time of LSCC patients were analyzed,and Kaplan-Meier method was used to draw the survival curve.The prognosis factor affecting the survival time of LSCC patients was analyzed using multivariate Cox proportional hazards regression analysis.Part Two1.In laryngeal squamous cell carcinoma cell line Hep-2 cells,q RT-PCR and Western blotting assays were performed to verify the expression of Tra2? after transfected with Tra2? si RNA and overexpressed plasmids(Tra2? vector).2.The in vitro effects of Tra2? expression in Hep-2 cells on their proliferation,invasion,and migration were assessed by CCK-8 assays,Matrigel invasion,and transwell migration assays.3.The effects of downregulation of Tra2? on the levels of apoptosis associated proteins(Bcl-2,BAX,Caspase-3)were measured using Western blot analysis and q RT-PCR analysis.In addition,the effects of downregulation of Tra2? on the activation of PI3K/AKT signaling pathway were measured using Western blot analysis.4.Constructed the Tra2? sh RNA virus,the Hep-2 induced LSCC nude mice was injected with Tra2? sh RNA virus,negative control virus or saline buffer.The tumor volumes and tumor growth inhibition ratio were dected once every 5 days.Results1.The results suggested the expression of Tra2? in tumor tissues with metastasis were significantly increased than that without metastasis through immunohistochemistry analysis,and Tra2? m RNA levels in LSCC tissues was increased than that in adjacent healthy tissues.Moreover,higher levels of tra2? expression was correlated with histological grade,lymph nodes metastasis.In addition,high levels of tra2? expression was related to a poor survival according to the Kaplan-Meier survival curves.Univariate analysis demonstrated that Tra2? expression was associated with poor prognosis of LSCC,and multivariate Cox proportional hazards regression analysis indicated that Tra2? expression was an independent prognostic marker for LSCC.2.In vitro Tra2? suppression caused a significant decrease in the proliferation.And Tra2? suppression additionally inhibited the invasive and migrative capacity of Hep-2 cells.3.Tra2? silencing decreased the expression of Bcl-2 but increased Bax and Caspase-3 both in m RNA and protein levels.4.Furthermore,knockdown of Tra2? eliminated the suppressive effects of activation of PI3K/AKT signaling.5.Injected with Tra2? silencing virus could inhibit the tumor volumes compared with negative control group.Conclusions1.The expression of Tra2? was significantly increased in LSCC tissues than that in adjacent healthy tissues,and Tra2? was an independent prognostic indicator of overall survival for LSCC patients,which all revealed that Tra2? may play a vital role in the oncogenesis and development of LSCC,and moreover Tra2? could be a new prognostic marker for LSCC.2.High expression of Tra2? promotes LSCC cell migration,invasion and proliferation.3.High expression of Tra2? promoted the expression of apoptosis associated proteins(Bcl-2)but facilitates the decreased expression of Bax and Caspase-3.Furthermore,Tra2? eliminated the suppressive effects of activation of PI3K/AKT signaling.4.In Hep-2 induced LSCC nude mice,Tra2? sh RNA virus could inhibit the growth of tumor.5.Tra2? promotes cell proliferation,invasion and migration of LSCC partly through activation of PI3K/AKT signaling pathway.