Serum and tissue leptin in lung cancer: A meta-analysis.
Many studies have found that leptin is involved in tumorigenesis and the progression of lung cancer. However, these studies were inconsistent. Therefore, we performed a meta-analysis to investigate the role of leptin in the patients with lung cancer. A systematic literature search in the several databases and on commercial Internet search engines was carried out to identify studies published up to July 8, 2016. The standardized mean difference (SMD) and odds ratio (OR) with 95% confidence interval (CI) were used to investigate the effect sizes. Finally, 21 eligible articles were included in the current meta-analysis. Overall, there is no relationship between levels of serum leptin and lung cancer. However, a subgroup analysis in high-study quality group found a weak association between serum leptin concentrations and lung cancer in Chinese (SMD=0.77, P=0.035). Additionally, the meta-analysis indicates that the serum leptin levels were lower in the weight-losing group than in the sustained weight group (SMD=-0.80, P=0.001). Further, there was evidence of a significant association between expression levels of leptin protein in tissue and lung cancer (OR=7.35, P<0.001). The present meta-analysis suggests that the serum and tissue leptin may be involved in the pathogenesis of lung cancer and tumor metastasis, especially among Chinese. However, the leptin may not appear to play an important role in cancer cachexia development.
Department of Respiratory and Critical Care Medicine, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China.
Xiang
X
Tong
Department of Respiratory and Critical Care Medicine, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China.
Yao
Y
Ma
Innovative Drug Research Centre, Chongqing University, Chongqing, 404100, China.
Qilong
Q
Zhou
Department of Respiratory Medicine, The First Affiliated Hospital of Chengdu Medical College, Chengdu, 610500, China.
Jie
J
He
Department of Internal Medicine, Hospital of Tradition Medicine LS.SC, Leshan, 614000, China.
Bo
B
Peng
Department of Respiratory and Critical Care Medicine, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China.
Sitong
S
Liu
Department of Respiratory and Critical Care Medicine, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China.
Zhipeng
Z
Yan
Department of Respiratory and Critical Care Medicine, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China.
Xin
X
Yang
Department of Respiratory and Critical Care Medicine, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China.
Hong
H
Fan
D016022:Case-Control Studies; D006801:Humans; D020738:Leptin / Q000378:metabolism*; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D011379:Prognosis
D020738:Leptin
cachexia; leptin; lung cancer; meta-analysis; risk