Active and passive smoking with breast cancer risk for Chinese females: a systematic review and meta-analysis

Previous studies suggested that smoking and passive smoking could increase the risk of breast cancer, but the results were inconsistent, especially for Chinese females. Thus, we systematically searched cohort and case-control studies investigating the associations of active and passive smoking with breast cancer risk among Chinese females in four English databases(PubMed, Embase, ScienceDirect, and Wiley) and three Chinese databases(CNKI, WanFang, and VIP). Fifty-one articles(3 cohort studies and 48 casecontrol studies) covering 17 provinces of China were finally included in this systematic review. Among Chinese females, there was significant association between passive smoking and this risk of breast cancer [odds ratio(OR): 1.62; 95% confidence interval(CI): 1.39–1.85; I2 = 75.8%, P < 0.001; n = 26] but no significant association between active smoking and the risk of breast cancer(OR: 1.04; 95% CI: 0.89–1.20; I2 = 13.9%, P = 0.248; n = 31). The OR of exposure to husband's smoking and to smoke in the workplace was 1.27(95% CI: 1.07–1.50) and 1.66(95% CI: 1.07–2.59), respectively. The OR of light and heavy passive smoking was 1.11 and 1.41, respectively, for women exposed to their husband's smoke(< 20 and ≥ 20 cigarettes per day), and 1.07 and 1.87, respectively, for those exposed to smoke in the workplace(< 300 and ≥ 300 min of exposure per day). These results imply that passive smoking is associated with an increased risk of breast cancer, and the risk seems to increase as the level of passive exposure to smoke increases among Chinese females. Women with passive exposure to smoke in the workplace have a higher risk of breast cancer than those exposed to their husband's smoking.

A bird's eye view of the air pollution-cancer link in China

Air pollution in China comes from multiple sources,including coal consumption,construction and industrial dust,and vehicle exhaust.Coal consumption in particular directly determines the emissions of three major air pollutants:dust,sulfur dioxide(SO2),and nitrogen oxide(NOx).The rapidly increasing number of civilian vehicles is expected to bring NOx emission to a very high level.Contrary to expectations,however,existing data show that the concentrations of major pollutants[particulate matter-10(PM10),SO2,and nitrogen dioxide(NO2)]in several large Chinese cities have declined during the past decades,though they still exceed the national standards of ambient air quality.Archived data from China does not fully support that the concentrations of pollutants directly depend on local emissions,but this is likely due to inaccurate measurement of pollutants.Analyses on the cancer registry data show that cancer burden related to air pollution is on the rise in China and will likely increase further,but there is a lack of data to accurately predict the cancer burden.Past experience from other countries has sounded alarm of the link between air pollution and cancer.The quantitative association requires dedicated research as well as establishment of needed monitoring infrastructures and cancer registries.The air pollution-cancer link is a serious public health issue that needs urgent investigation.

Advances in circulating microRNAs as diagnostic and prognostic markers for ovarian cancer

Ovarian cancer is one of the most lethal malignant gynecological tumors. More than 70% of patients with ovarian cancer are diagnosed at advanced stage. The 5-year survival in patients with advanced ovarian cancer is less than 30% because of the lack of effective biomarkers for diagnosis, prognosis, and personalized treatment. MicroRNA （miR） is a class of small noncoding RNAs that negatively regulate gene expression primarily through post-transcriptional repression. Many studies on tissue miR in ovarian cancer have been carried out and show great potential in clinical practice. However, tissue samples are not easily available because sampling causes injur）n Researchers have started to focus on plasma/serum miR, assuming that blood samples may replace tissue samples in miR research in the future. Plasma/serum miR research is still in its early stages. Studies on its function in the early diagnosis of ovarian cancer have achieved some progress, but plasma/serum miR profiling for prognosis and personalized treatment of ovarian cancer remains unknown. A thorough understanding of the function of plasma/serum miR in ovarian cancer will facilitate early diagnosis and improve treatment for ovarian cancer.

Pouch size influences clinical outcome of pouch construction after total gastrectomy:A meta-analysis

AIM: To assess the clinical significance of pouch size in total gastrectomy for gastric malignancies.