Impact of environmental factors on gastric cancer: A review of the scientific evidence, human prevention and adaptation

Globally, gastric cancer (GC) ranks fifth in prevalence and third in fatalities, and shows a distinct geographical distribution in morbidity and mortality. Such a spatial pattern indicates that environmental factors could be an important contributor to GC. We reviewed a total of 135 relevant peer-reviewed articles and other literature published 1936–2019 to investigate the scientific evidence concerning the effects of environmental factors on GC worldwide. Environmental factors affect GC from the aspects of water, soil, air, radiation, and geology. Risk factors identified include water type, water pollution, water hardness, soil type, soil pollution, soil element content, climate change, air pollution, radiation, altitude, latitude, topography, and lithology; and most of them have an adverse impact on GC. Furthermore, we found that their effects followed five common rules: (1) the leading environmental factors that affect GC incidence and mortality vary by region, (2) the same environmental factors may have different effects on GC in different regions, (3) some different environmental factors have similar effects on GC in essence, (4) different environmental factors often interact to have combined or synergistic effects on GC, and (5) environmental factors can affect human factors to have an impact on GC. Environmental factors have a great impact on GC. Human beings may prevent GC by controlling carcinogenic factors, screening high-risk populations and providing symptomatic and rehabilitative treatments. Furthermore, adaptation measures are recommended to reduce GC risk on private and public levels. Future studies should transcend existing empirical studies to develop causal relationship models and focus on vulnerable population analysis.     

Air pollution and liver cancer: A systematic review

Air pollution has previously been linked to several adverse health outcomes, but the potential association between air pollution and liver cancer remains unclear. We searched PubMed, EMBASE, and Web of Science from inception to 10 October 2021, and manually reviewed the references of relevant papers to further identify any related literature investigating possible associations between air pollution and liver cancer. Risk estimates values were represented by statistical associations based on quantitative analyses. A total of 13 cohort studies obtained from 11 articles were included, with 10,961,717 participants. PM_2.5 was the most frequently examined pollutant (included in 11 studies), followed by NO₂ and NO_x (included in 6 studies), and fewer studies focused on other pollutants (PM_{2.5 absorbance}, PM₁₀, PM_2.5–10, O₃, and BC). In all the 16 associations for liver cancer mortality, 14 associations reported the effect of PM_2.5 on liver cancer mortality. Eight associations on PM_2.5 were significant, showing a suggestive association between PM_2.5 and liver cancer mortality. Among 24 associations shown by risk estimates for liver cancer incidence, most associations were not statistically significant. For other air pollutants, no positive associations were presented in these studies. PM_2.5 was the most frequently examined pollutant, followed by NO₂ and NO_x, and fewer studies focused on other pollutants. PM_2.5 was associated with liver cancer mortality, but there was no association for other air pollutants. Future research should use advanced statistical methods to further assess the impact of multiple air pollutants on liver cancer in the changing socio-environmental context.     

双酚A诱导人乳腺癌MCF-7细胞上皮间质化的研究

双酚A(BPA)是一类典型的环境雌激素,能干扰机体正常内分泌系统.作为一种激素相关疾病,乳腺癌的发生发展与BPA暴露的关系已引起人们的关注.本研究旨在探讨BPA对人乳腺癌MCF-7细胞上皮细胞间质化(EMT)的诱导作用.经BPA处理的MCF-7细胞,采用MTT试验检测BPA对细胞活力的影响,Transwell试验检测BPA对细胞迁移能力的影响,Real-time RT-PCR、Western Blot检测BPA对上皮型蛋白标志物E-cadherin、间质型蛋白标志物Vimentin及EMT相关转录因子Snail表达的影响.结果发现,低浓度BPA能够促进MCF-7细胞的增殖,显著增强细胞的迁移能力.BPA处理能抑制E-cadherin的表达,促进Vimentin及Snail的表达.研究结果提示,BPA处理可能通过促进Snail的表达而调控EMT相关蛋白标志物的表达,进而增强乳腺癌MCF-7细胞的迁移能力.     

Arsenic, Cadmium, Lead, and Mercury in surface soils, Pueblo, Colorado: implications for population health risk

Decades of intensive industrial and agricultural practices as well as rapid urbanization have left communities like Pueblo, Colorado facing potential health threats from pollution of its soils, air, water and food supply. To address such concerns about environmental contamination, we conducted an urban geochemical study of the city of Pueblo to offer insights into the potential chemical hazards in soil and inform priorities for future health studies and population interventions aimed at reducing exposures to inorganic substances. The current study characterizes the environmental landscape of Pueblo in terms of heavy metals, and relates this to population distributions. Soil was sampled within the city along transects and analyzed for arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb). We also profiled Pueblo’s communities in terms of their socioeconomic status and demographics. ArcGIS 9.0 was used to perform exploratory spatial data analysis and generate community profiles and prediction maps. The topsoil in Pueblo contains more As, Cd, Hg and Pb than national soil averages, although average Hg content in Pueblo was within reported baseline ranges. The highest levels of As concentrations ranged between 56.6 and 66.5 ppm. Lead concentrations exceeded 300 ppm in several of Pueblo’s residential communities. Elevated levels of lead are concentrated in low-income Hispanic and African-American communities. Areas of excessively high Cd concentration exist around Pueblo, including low income and minority communities, raising additional health and environmental justice concerns. Although the distribution patterns vary by element and may reflect both industrial and non-industrial sources, the study confirms that there is environmental contamination around Pueblo and underscores the need for a comprehensive public health approach to address environmental threats in urban communities.     

论大气环境污染与人体肺癌发生率

大气环境污染和人体肺癌发生率密切相关。工业和交通排放大气污染物、厨房污染、吸烟、复印机和居室装饰等造成的大气环境污染过程均能造成居民肺癌发病率的上升。应通过控制工业污染、改变能源结构、戒烟及绿化造林等措施加以解决。     

Nitrogen decontamination by molybdenum in high incidence area of esophageal cancer

Molybdenum (Mo) deficiency and nitrogen contamination have been proved to be relevant to the higher incidence of esophageal cancer. In order to reduce the amount of nitrate and nitrite in grains and vegetables, ammonium molybdate has been used as a trace-element fertilizer in Linxian County, a high risk area of esophageal cancer. This supplementation has significantly raised the yield and the Mo content of the crops. The nitrate and nitrite levels in crops and vegetables were reduced by 12-53 and 20-32% respectively. The amount of ascorbic acid in vegetables which can block the in vivo synthesis of nitroso compounds is increased by 10-70%.Taking the inhibitory effect of Mo on cancer into account, Mo supplement by using Mo fertilizer probably can serve as an effective chemoprevention measure against this disease in high risk areas.     

Environment and cancer in Shanghai

Shanghai is the biggest industrial city in China, and the problem of environmental pollution is rather serious. This article, taking Shanghai as an example, is to discuss: a general view of Shanghai's environment; the present situation and characteristics of cancer in Shanghai; analyses of the environmental factors of some kinds of cancers. The paper emphasizes the relationship between the environment and cancer in Shanghai, especially the environmental pollution and cancer. The aim of the article is not only to call people's concern to the pollution , but also to study the causes of some cancers.     

香烟中的钋-210与肺癌

本文根据文献报道,综述国内外香烟中~(210)Po放射性水平及其对人体健康的危害;介绍吸人烟雾中~(210)Po-导致肺癌发生的动物试验结果及对低剂量。辐射致癌的危险度估算,指出吸烟作为诱发呼吸系统癌变的污染源,应予控制。