Loss of claudin-7 is a negative prognostic factor for invasion and metastasis in oral squamous cell carcinoma

Oncol Rep. 2013 Feb;29(2):445-50. doi: 10.3892/or.2012.2161. Epub 2012 Nov 30.


Claudin-7 belongs to the claudin family, which consists of 24 subtypes of essential tight junction (TJ) integral membrane proteins with molecular weights of 20-27 kDa. We investigated the interrelationship between clinicopathological findings and claudin-7 expression in oral squamous cell carcinoma (OSCC). Using immunohistochemical techniques to examine the expression levels of claudin-7 in 67 cases of OSCC, claudin-7 expression was detected in 35 (52.2%) of the 67 cases. We also compared the clinicopathological features of the OSCC cases with claudin-7 expression levels. Moreover, six cell lines with various invasive properties were investigated in vitro to compare mRNA and protein levels of claudin-7 using reverse transcription-polymerase chain reaction (RT-PCR) and the western blotting method. Decreased claudin-7 expression correlated significantly with T-category (p<0.05), lymph node metastasis (p<0.01), and mode of invasion (p<0.001). Patients with positive claudin-7 expression had a significantly better prognosis (p<0.05). Claudin-7 protein and mRNA levels were lower in the HOC313 and TSU cells, which have higher invasive potentials compared with other cell lines. These results suggest that loss of claudin-7 expression is associated closely with invasion and lymph metastasis and is an unfavorable prognostic factor in patients with OSCC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / metabolism*
  • Cadherins / metabolism
  • Carcinoma, Squamous Cell / metabolism*
  • Carcinoma, Squamous Cell / secondary*
  • Cell Line, Tumor
  • Claudins / genetics
  • Claudins / metabolism*
  • Female
  • Humans
  • Immunohistochemistry
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Mouth Neoplasms / metabolism*
  • Mouth Neoplasms / pathology*
  • Neoplasm Invasiveness
  • Neoplasm Staging
  • Prognosis
  • RNA, Messenger / metabolism
  • Snail Family Transcription Factors
  • Survival Rate
  • Transcription Factors / metabolism


  • Biomarkers, Tumor
  • CLDN7 protein, human
  • Cadherins
  • Claudins
  • RNA, Messenger
  • Snail Family Transcription Factors
  • Transcription Factors