Clinicopathological significance and potential drug targeting of CDH1 in lung cancer: a meta-analysis and literature review.
BACKGROUND
CDH1 is a protein encoded by the CDH1 gene in humans. Mutations in this gene are linked with several types of cancer. Loss of CDH1 function contributes to the progression of cancer by increasing proliferation, invasion, and/or metastasis. However, the association between and clinicopathological significance of CDH1 promoter methylation and lung cancer remains unclear. In this study, we systematically reviewed the studies of CDH1 promoter methylation and lung cancer, and evaluated the association between CDH1 promoter methylation and lung cancer using meta-analysis methods.


METHODS
A comprehensive search of the PubMed and Embase databases was performed up to July 2014. The methodological quality of the studies was also evaluated. The data were extracted and assessed by two reviewers independently. Analyses of pooled data were performed. Odds ratios (ORs) were calculated and summarized.


RESULTS
Finally, an analysis of 866 patients with non-small cell lung cancer from 13 eligible studies was performed. The CDH1 methylation level in the cancer group was significantly higher than in the controls (OR 3.89, 95% confidence interval [CI] 2.87-5.27, P<0.00001). However, there were no correlations between CDH1 promoter methylation and clinicopathological characteristics (sex status, OR 0.78, 95% CI 0.41-1.50, P=0.46; smoking history, OR 0.97, 95% CI 0.53-1.79, P=0.93; pathological type, OR 0.97, 95% CI 0.59-1.60, P=0.91; clinical staging, OR 1.48, 95% CI 0.81-2.68, P=0.2; lymph node metastasis, OR 0.68, 95% CI 0.13-3.63, P=0.65; or differentiation degree, OR 1.01, 95% CI 0.34-3.02, P=0.99).


CONCLUSIONS
The results of this meta-analysis suggest that CDH1 methylation is associated with an increased risk of lung cancer. CDH1 hypermethylation, which induces inactivation of the CDH1 gene, plays an important role in carcinogenesis and may serve as a potential drug target in lung cancer. However, CDH1 methylation does not correlate with other factors, such as smoking history, clinical stage, pathological type, sex status, lymph node metastasis, or degree of differentiation.
Shandong Provincial Key Laboratory of Mental Disorders, Research Center for Sectional and Imaging Anatomy, Shandong University School of Medicine, Beijing, People's Republic of China.
Qiaowen
Q
Yu
Respiratory Medicine, Shandong Cancer Hospital, Jinan, Beijing, People's Republic of China.
Qisen
Q
Guo
Department of Respiratory Diseases, People's Liberation Army General Hospital, Beijing, People's Republic of China.
Liangan
L
Chen
Shandong Provincial Key Laboratory of Mental Disorders, Research Center for Sectional and Imaging Anatomy, Shandong University School of Medicine, Beijing, People's Republic of China.
Shuwei
S
Liu
D015703:Antigens, CD; D015820:Cadherins / Q000235:genetics* / Q000378:metabolism*; D016503:Drug Delivery Systems; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology
D015703:Antigens, CD; C513384:CDH1 protein, human; D015820:Cadherins
CDH1; lung cancer; meta-analysis; methylation; odds ratio; tumor suppressor gene