Can statins reduce risk of lung cancer,especially among elderly people? A meta-analysis

Objective： As the most common cause of cancer mortality throughout the world, lung cancer has drawn people＇s attention on how to reduce the risk with chemopreventive ways. Many epidemiological studies have shown inconsistent effects of statins on lung cancer, but some observational studies have showed that statins had protective effect on lung cancer among elderly people. So we preformed this meta-analysis to find whether statins were chemopreventive. Methods： We searched MEDLINE, EMBASE and Web of Science databases from inception to September, 2013. A total of 23 studies were selected, including 15 observational studies and 8 randomized controlled trials （RCTs）. Both fixed and random-effects models were used to calculate pooled estimates in primary and sensitivity analyses. We used Q and 12 statistics to assess statistical heterogeneity, and evaluated publication bias by Begg＇s test and Egger＇s test. Results： No association between statins and lung cancer risk was identified either in the meta-analysis among RCTs [relative risk （RR）： 0.95, 95% confidence interval （95% CI）： 0.85-1.06] or observational studies （RR： 0.89, 95% CI： 0.77-1.04）. We also selected 6 observational studies that all researched on elderly people. The result of meta-analysis showed that there was still no protective effect between statins and lung cancer among elderly people （RR： 1.03, 95% CI： 0.96-1.11）. Conclusions： Our results did not support a protective effect of statins on the overall lung cancer risk and the lung cancer risk among elderly people. More well-designed RCTs are needed to enhance our understanding of the chemopreventive effect of statins on lung cancer.

Nanosecond pulsed electric fields prime mesenchymal stem cells to peptide ghrelin and enhance chondrogenesis and osteochondral defect repair in vivo

Mesenchymal stem cells(MSCs) are important cell sources in cartilage tissue development and homeostasis,and multiple strategies have been developed to improve MSCs chondrogenic differentiation with an aim of promoting cartilage regeneration.Here we report the effects of combining nanosecond pulsed electric fields(ns PEFs) followed by treatment with ghrelin(a hormone that stimulates release of growth hormone) to regulate chondrogenesis of MSCs.ns PEFs and ghrelin were observed to separately enhance the chondrogenesis of MSCs,and the effects were significantly enhanced when the bioelectric stimulation and hormone were combined,which in turn improved osteochondral tissue repair of these cells within Sprague Dawley rats.We further found that ns PEFs can prime MSCs to be more receptive to subsequent stimuli of differentiation by upregulated Oct4/Nanog and activated JNK signaling pathway.Ghrelin initiated chondrogenic differentiation by activation of ERK1/2 signaling pathway,and RNA-seq results indicated 243 genes were regulated,and JAK-STAT signaling pathway was involved.Interestingly,the sequential order of applying these two stimuli is critical,with ns PEFs pretreatment followed by ghrelin enhanced chondrogenesis of MSCs in vitro and subsequent cartilage regeneration in vivo,but not vice versa.This synergistic prochondrogenic effects provide us new insights and strategies for future cell-based therapies.