title: Adenovirus expressing IFN-λ (Ad/hIFN-λ) produced anti-tumor effects through inducing apoptosis in human tongue squamous cell carcinoma cell.
abstract: OBJECTIVE
  To investigate the potential therapeutic effects of adenovirus expressing IFN-λ1 and IFN-λ2 (Ad/hIFN-λ) in treating squamous cell carcinoma of the oral tongue (SCCOT) and to explore the underlying mechanisms.
  
  
  METHODS
  Two SCCOT cell lines HSC-3 and Tca8113 were adopted as study objects. Cell Counting Kit-8 (CCK-8) cell proliferation and viability assay was performed to evaluate the antiproliferative effects of Ad/hIFN-λ and IFN-λ treatments at different dosages. Flow cytometry (FCM) was performed to investigate the apoptosis rate induced by Ad/hIFN-λ. In vivo study was performed through evaluating tumorigenicity and tumor volume on BALB/c nu/nu mice inoculated with HSC-3 cells with or without infection of Ad/hIFN-λ. qPCR was used to screen important apoptosis related genes expression and western blot (WB) was performed to verify the results. WB was also used to test the phosphorylation of STATs protein in the JAK/STAT signaling pathways.
  
  
  RESULTS
  Our results indicated an obvious antiproliferative effect of Ad/hIFN-λ in vitro on infected HSC-3 and Tca8113 cells. The antiproliferative effects started to appear at 48 h (day 2) after infection. IFN-λs alone treating HSC-3 and Tca8113 cells also showed a dose-dependent inhibitory manner. Though the antiproliferative effects did not show on 24 h (day 1), early apoptosis rate already increased significantly in cells infected with Ad/hIFN-λ (P<0.05) detected by FCM. The underlying mechanisms of antiproliferative activity rely on the IFN-λ signaling by phosphorylation of STATs protein. Expression of Bax, Bcl-2 and Caspase-3 were promoted by Ad/hIFN-λ leading to higher apoptosis rate. Upper stream of p21 and Rb dephosphorylation explained the Caspase-3 activation. Animal study showed that HSC-3 cells infected with Ad/hIFN-λ significantly promoted the survival rate and decreased mean tumor volume comparing to HSC-3 cells group.
  
  
  CONCLUSIONS
  Ad/hIFN-λ injection had obvious antiproliferative effects on HSC-3 and Tca8113 cells. Ad/hIFN-λ induced apoptosis in SCCOT cells through increasing Bcl-2, Bax and Caspase-3 expression. Ad/hIFN-λ is a potential therapeutic strategy in treating oral tongue carcinoma.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Binzhou Medical University Hospital Binzhou 256603, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Song
authors.affiliation: Department of Oral and Maxillofacial Surgery, Binzhou Medical University Hospital Binzhou 256603, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Stomatology, Binzhou People's Hospital Binzhou 256600, China.
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Wang
authors.affiliation: Department of Stomatology, Binzhou People's Hospital Binzhou 256600, China.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Fan
authors.affiliation: Department of Oral and Maxillofacial Surgery, Binzhou Medical University Hospital Binzhou 256603, China.
authors.forename: Yu-Mei
authors.initials: YM
authors.lastname: Huang
authors.affiliation: Department of Oral and Maxillofacial Surgery, Binzhou Medical University Hospital Binzhou 256603, China.
authors.forename: Hao-Su
authors.initials: HS
authors.lastname: Ci
authors.affiliation: Department of Oral and Maxillofacial Surgery, Binzhou Medical University Hospital Binzhou 256603, China.
authors.forename: Jin-Hua
authors.initials: JH
authors.lastname: Zuo
keywords: Adenovirus; IFN-λ; JAK/STAT; apoptosis; oral tongue carcinoma