title: Abnormal expression of PI3K isoforms in patients with tobacco-related oral squamous cell carcinoma.
abstract: BACKGROUND
  The phosphatidylinositol 3-kinase (PI3K) signaling regulates several cellular functions such as motility, proliferation, angiogenesis and survival.
  
  
  METHODS
  Since there is no information on expression of PI3K isoforms in oral cancer, we studied the expression of different isoforms of PI3K (p110α, p110γ, PI3K-C2, Vps34p and p85α) in tumor samples and PBMC by RT and q-RTPCR and serum levels of PI3K p110α by SPR and ELISA techniques in 108 patients with tobacco-related oral squamous cell carcinoma (OSCC) and 46 normal subjects.
  
  
  RESULTS
  We observed significantly higher PI3K p110α (p<0.0001) and lower (p<0.0001) vesicular sorting protein 34p (Vps34p) mRNA both in PBMC and tissue samples of oral cancer patients as compared to the normal controls. Other PI3K isoforms did not show such change. Circulating PI3K p110α levels were higher in patients (p<0.0001) as compared to healthy subjects, the SPR data showed direct correlation with advancing stage of the disease. PI3K p110α was overexpressed in tumor samples but not in the normal buccal mucosa.
  
  
  CONCLUSIONS
  Upregulation of circulating PI3K p110α isoform and its direct correlation with increasing tumor load in OSCC patients indicates that it may be a significant prognostic indicator and a suitable target for therapeutic/chemo-preventive strategies for tobacco-related OSCC.
authors.affiliation: Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi-110029, India.
authors.forename: Richa
authors.initials: R
authors.lastname: Garg
authors.forename: Vaishali
authors.initials: V
authors.lastname: Kapoor
authors.forename: Manasi
authors.initials: M
authors.lastname: Mittal
authors.forename: Manoj K
authors.initials: MK
authors.lastname: Singh
authors.forename: Nootan K
authors.initials: NK
authors.lastname: Shukla
authors.forename: Satya N
authors.initials: SN
authors.lastname: Das
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000503:physiopathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000235:genetics* / Q000503:physiopathology; D058539:Phosphatidylinositol 3-Kinase / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism; D059467:Transcriptome
chemical_list: D020033:Protein Isoforms; D012333:RNA, Messenger; D058539:Phosphatidylinositol 3-Kinase