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Accumulating data suggest that adipose tissue facilitates breast tumor initiation and progression through paracrine and endocrine pathways, and that adipose tissue-derived stem cell (ASC) is likely the major cell type responsible for tumorigenesis and tumor development. However, it remains unknown how ASCs exert their effects. In the present study, in cultured breast cancer cell lines, including estrogen receptor (ER)-positive MCF-7 cells and ER-negative MDA-MB-231 cells, the effects on tumor proliferation of isolated ASCs from human breasts were examined. The expression of 174 cytokines was additionally identified in this medium. With an anti-human C-X-C motif ligand 5 (CXCL5) monoclonal antibody, the effects of neutralization of CXCL5 on the actions of ASCs in a co-culture medium of ASCs and tumor cells were studied The results demonstrated that ASCs significantly increased the number of breast cancer cells compared with controls. Similarly, the co-culture medium of ASCs with breast cancer cells exhibited potent effects on tumor cell proliferation. In the co-culture medium of ASCs with breast cancer cells, CXCL5 levels were significantly increased. In addition, depletion of CXCL5 with its specific antibody in ASC-conditioned medium blocked the stimulatory effect of ASCs on the proliferation of breast cancer cells. To the best of our knowledge, these results indicate for the first time that ASC-secreted CXCL5 is a key factor promoting breast tumor cell proliferation.

This study examines the relationship between total renewable electricity generation, total hydroelectric generation, and carbon dioxide emissions (CO2e) for China. The autoregressive distributed lag (ARDL) model showed that renewable electricity generation, hydroelectric generation, and green innovation decreased CO2e in China from 1990 to 2018, whereas gross domestic product per capita and foreign direct investment increased CO2e. Moreover, the Granger-causality test results are as follows. First, a two-way causal flow from CO2e to foreign direct investment and CO2e to gross domestic product per capita confirmed the feedback hypothesis. Second, a one-way causal flow from hydroelectric and renewable electricity generation to gross domestic product per capita supported the energy-led growth hypothesis. Third, the causality test reflected a one-way causal flow from renewable electricity generation to foreign direct investment and hydroelectric generation to foreign direct investment and renewable electricity generation. This study asserts the need for government to introduce taxes and other incentives for solar, wind, and hydropower-related projects. The paper also calls for designing policies to improve the market attractiveness of hydroelectric generation projects through special investment programs.

Yupeng Liu,1,2Xiaosan Zhang,3 Hongru Sun,2 Shu Zhao,4 Yuxue Zhang,5 Dapeng Li,2 Qingyuan Zhang,4 Yashuang Zhao21Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou 325035, People’s Republic of China; 2Department of Epidemiology, Public Health School of Harbin Medical University, Harbin 150081, People’s Republic of China; 3Department of Internal Medicine, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou 450008, People’s Republic of China; 4Department of Medical Oncology, The Third Affiliated Hospital of Harbin Medical University, Heilongjiang Cancer Hospital, Harbin 150081, People’s Republic of China; 5Department of Preventive Medicine, Public Health School of Harbin Medical University, Harbin 150081, People’s Republic of ChinaImportance: Prevention of primary breast cancer (BCa) in women is of great public health importance. The existing results from observational epidemiologic studies focused on the association between bisphosphonates and primary BCa risk have been inconsistent.Objective: To update this systematic review and meta-analysis to assess the effect of bisphosphonates on primary BCa risk.Data sources: We comprehensively searched MEDLINE, EMBASE, Cochrane libraries, ProQuest, and Web of Science through June 25, 2018 for relevant studies.Study selection: Epidemiological studies that assessed the effect of bisphosphonates on the risk of primary BCa in women.Data extraction and synthesis: We reported this meta-analysis according to the PRISMA guidelines. Available multivariable-adjusted effect estimates and corresponding 95% CIs were pooled with a random-effects model.Main outcomes and measures: The prespecified main outcome was the risk of primary BCa.Results: In total, five cohort studies involving 657,558 women and 12,991 primary BCa patients, three population-based case-control studies involving 54,701 primary BCa cases and 237,962 healthy controls and two randomized controlled trials (RCTs) involving 13,774 women and 165 primary BCa patients were included in this meta-analysis. Bisphosphonates were associated with a 12% decreased risk of primary BCa (RR, 0.88; 95% CI, 0.83–0.94). However, when we analyzed study designs separately, the pooled results from observational studies were inconsistent with that from RCTs. The observed association of primary BCa risk with long-term use (≥1 year) of bisphosphonates seemed to be more robust and stronger than that of short-term use (