[Show abstract][Hide abstract] ABSTRACT: Klotho (KL) is a transmembrane protein that can be shed, and act as a circulating hormone and modulate several signaling pathways. There also exists a splice variant of Klotho mRNA, which encodes a putative secreted protein (Klotho-S, KL-S) in both human and mouse. The potential anti-senescence gene Klotho has been recently found to participate in the progression of several different human cancers. In the current study, we undertook to study the expression and activity of Klotho in lung cancer cell line A549. Klotho expression was studied by using RT-PCR and western blotting. Effects of Klotho on cell growth and motility were assessed using MTT and scratch motility assay, and the apoptosis was assessed by TUNEL. Wnt signaling pathway activity was measured by western blotting. We established that the Klotho was endogenous expressed in A549 cells, but the expression level is lower compared with normal lung tissues. The overexpression of KL or KL-S could inhibit the cell proliferation, motility, and induce apoptosis in a dose-dependent manner. Also, we report KL could inhibit activation of Wnt -TCF/β-catenin signaling pathway, and it is involved in KL-induced growth inhibition. These studies indicate Klotho works as a potential tumor suppressor in lung cancer, and suggest that the Klotho tumor suppressive activities could be mediated through its KL-S isoform. These results suggest the use of Klotho or KL-S as potential strategy for the development of novel therapeutic interventions for lung cancers.
[Show abstract][Hide abstract] ABSTRACT: MicroRNAs regulate gene expression at the post-transcriptional level and involved in diverse biological and pathological processes, including tumorigenesis. Rs11614913 in miR-196a2 and rs2910164 in miR-146a are shown to associate with increased/decreased cancer risk. We performed a meta-analysis to systematically summarize the possible association.
We assessed published studies of the association between these microRNA polymorphisms and cancer risk from eleven studies with 16,771 subjects for miR-196a2 and from ten studies with 15,126 subjects for miR-146a. As for rs11614913, the contrast of homozygote (TT vs CC: OR = 0.92, 95% CI = 0.85-0.99, P(heterogeneity) = 0.45), allele (T vs C: OR = 0.96, 95% CI = 0.92-0.99, P(heterogeneity) = 0.61) and recessive model (OR = 0.90, 95% CI = 0.84-0.97, P(heterogeneity) = 0.50) produced statistically association. Subgroup analysis by ethnicity, statistically significantly decreased cancer risks were found among Asians for allele contrast (OR = 0.95, 95% CI = 0.90-0.99, P(heterogeneity) = 0.74) and the recessive genetic model (OR = 0.90, 95% CI = 0.82-0.98, P(heterogeneity) = 0.85). According to subgroup analysis by tumor types, the protective effect of C/T polymorphism was only found in breast cancer under allele contrast (T vs C: OR = 0.94, 95% CI = 0.88-0.99, P(heterogeneity) = 0.26). For rs2910164, no significant associations were found among overall analysis model with relatively large heterogeneity. Through the stratified analysis, heterogeneity decreased significantly. In the subgroup analyses by cancer types, the C allele of rs2910164 was associated with protection from digestive cancer in allele contrast (C vs G: OR = 0.86, 95% CI = 0.77-0.96, P(heterogeneity) = 0.51).
Our meta-analysis suggests that the rs11614913 most likely contributes to decreased susceptibility to cancer, especially in Asians and breast cancer. Besides, the C allele of the rs2910164 might be associated with a protection from digestive cancer.
PLoS ONE 05/2011; 6(5):e20471. DOI:10.1371/journal.pone.0020471 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although the roles of soluble CD40 ligand (sCD40L) or the klotho gene in lung cancer cells have been studied, little is known about the functions of klotho combined with sCD40L in lung cancer. The present study was designed to investigate the biological effects of klotho combined with sCD40L on the A549 lung cancer cell line (CD40 positive) and their possible mechanisms. Lung cancer A549 cells were chosen as target cells and CD40 signals were stimulated by soluble CD40 ligand (sCD40L). In this study, we found that klotho, soluble CD40 ligand and their combination can increase cell proliferation inhibition and the apoptosis rate in A549 cells by inhibiting the cell cycle, up-regulating Bax gene expression and (or) down-regulating Bcl-2 gene expression; and their combination has a stronger effect on A549 cell apoptosis and proliferation inhibition compared to klotho or sCD40L alone. These data suggest that the combination of klotho and sCD40L may provide an efficient method to treat non-small cell lung cancer.
[Show abstract][Hide abstract] ABSTRACT: Fibroblast growth factor receptor 4 (FGFR4), belonging to the receptor tyrosine kinase family, is involved in cancer initiation and progression. The FGFR4 Gly388Arg polymorphism in the transmembrane domain of the receptor was shown to contribute to genetic susceptibility to cancer but the results were inconsistent. We performed a meta-analysis using 12 eligible case-control studies with a total of 4892 patients and 3663 controls to summarise the data on the association between the FGFR4 Gly388Arg polymorphism and cancer risks. The overall odds ratio (OR) with a 95% confidence interval (CI) showed statistical association between the FGFR4 Gly388Arg polymorphism and cancer risks under homozygote comparison, allele contrast and the recessive genetic model. In the subgroup analysis by ethnicity, statistically significantly increased cancer risks were found among Asians for homozygote comparison (OR = 1.43, 95% CI = 1.13-1.80, P(heterogeneity)=0.24), allele contrast (OR = 1.16, 95% CI = 1.04-1.29, P(heterogeneity) = 0.25) and the recessive genetic model (OR = 1.47, 95% CI = 1.19-1.81, P(heterogeneity) = 0.15). In the subgroup analysis for different tumour types, Arg(388) allele had an effect of increasing the risks of breast (homozygote comparison OR = 1.57, 95% CI = 1.04-2.37, P(heterogeneity) = 0.83 and the recessive model OR = 1.51, 95% CI = 1.02-2.24, P(heterogeneity) = 0.80) and prostate cancer (Gly/Arg versus Gly/Gly: OR = 1.16, 95% CI = 1.02-1.32, P(heterogeneity)=0.74; Arg versus Gly: OR = 1.17, 95% CI = 1.07-1.29, P(heterogeneity) = 0.18 and the dominant model: OR = 1.20, 95% CI = 1.06-1.35, P(heterogeneity) = 0.89). Our meta-analysis suggests that the FGFR4 Gly388Arg polymorphism most likely contributes to susceptibility to cancer, especially in Asians. Besides, the Arg(388) allele might be associated with increased risks of breast and prostate cancer.
European journal of cancer (Oxford, England: 1990) 12/2010; 46(18):3332-8. DOI:10.1016/j.ejca.2010.06.017 · 5.42 Impact Factor