title: Decrease of autophagy activity promotes malignant progression of tongue squamous cell carcinoma.
abstract: BACKGROUND
  Autophagy is a catabolic process involving the degradation of cells' own unnecessary, injured, or aged proteins and recycling of degraded products to maintain hemostasis. Recently, studies indicated that autophagy plays a crucial role in cancer development. However, the role of autophagy in tongue squamous cell carcinoma (TSCC) has not been well documented. This study aims to assess the expression of autophagy-related protein and investigate its effect on TSCC.
  
  
  METHODS
  Archival 50 TSCC samples were enrolled. Immunohistochemistry were performed to examine the expression of Beclin1 and LC3. Statistical analyses were carried out to assess the associations among clinicopathologic parameters. In vitro, cells were treated with rapamycin or 3-MA. Then, qPCR, western blot and immunofluorescence were performed to detect the expression of Beclin1 and LC3. Transmission electron microscopy was utilized to identify autophagsomes. For functional analysis, cell proliferation and cell cycle were evaluated with MTT assay and flow cytometer, respectively. At last, cell migration and invasion potentials were assessed by wound healing assay and transwell assay.
  
  
  RESULTS
  We confirmed that down-regulation of Beclin1 and LC3 is a frequent event in TSCC. Then, we demonstrated that decreased expression of Beclin1 was associated with T stage, clinical stage and differentiation. Furthermore, we showed that activation of autophagy by rapamycin suppressed proliferation, migration and invasion while inhibition of autophagy by 3-MA promoted proliferation, migration and invasion in TSCC cells.
  
  
  CONCLUSIONS
  Taken together, these data suggest that autophagy plays a pivotal role in the progression of TSCC.
authors: Department of Oral and Maxillofacial Surgery, Guanghua School and Research Institute of Stomatology, Sun Yat-sen University, Guangzhou, China.
authors: Yawen
authors: Y
authors: Wang
authors: Cheng
authors: C
authors: Wang
authors: Haikuo
authors: H
authors: Tang
authors: Miao
authors: M
authors: Wang
authors: Junquan
authors: J
authors: Weng
authors: Xiqiang
authors: X
authors: Liu
authors: Rong
authors: R
authors: Zhang
authors: Hongzhang
authors: H
authors: Huang
authors: Jinsong
authors: J
authors: Hou
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000494:pharmacology; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D051017:Apoptosis Regulatory Proteins / Q000032:analysis; D001343:Autophagy / Q000187:drug effects / Q000502:physiology*; D000071186:Beclin-1; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D002453:Cell Cycle / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D008869:Microtubule-Associated Proteins / Q000032:analysis; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010588:Phagosomes / Q000473:pathology; D020123:Sirolimus / Q000494:pharmacology; D014062:Tongue Neoplasms / Q000473:pathology*
chemical_list: D000903:Antibiotics, Antineoplastic; D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; C477012:MAP1LC3A protein, human; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; C025946:3-methyladenine; D000225:Adenine; D020123:Sirolimus
keywords: Beclin1; LC3; autophagy; tongue squamous cell carcinoma