SEGH Articles

Chronic cadmium exposure promotes nasopharyngeal carcinoma progression and radioresistance

24 January 2019
Dr Lin Peng and her team investigate how environmental pollutant exposure influences the risk of cancer development and therapeutic resistance at the Clinical Laboratory, Cancer Hospital of Shantou University Medical College, China.

Dr Lin Peng, Associate Chief Physician, works in Clinical Laboratory, Cancer Hospital of Shantou University Medical College in China. The research team she leads focuses on environmental pollutant exposure and the risk of cancer development and therapeutic resistance. Her team has recently published research results highlighting the association between cadmium and breast cancer, connecting gastrointestinal cancer risk to cadmium and lead exposure and the association of polychlorinated biphenyls/polybrominated diphenyl ethers with breast cancer risk.

Lin Peng analysing blood samples

Lin Peng analysing blood samples

Nasopharyngeal carcinoma (NPC) is a unique malignancy with a high prevalence in East and Southeast Asia, especially in southern China. The unique ethnic and geographical distribution of NPC indicates hereditary factor and environmental factors may contribute to its unusual etiology. But to date, only nitrosamine, polycyclic aromatic hydrocarbons and nickel are regarded as environmental risk factors in the development and progression of NPC. Cadmium is a ubiquitous carcinogenic pollutant related with some human cancers. The aim of the present study was to evaluate the association between chronic low-concentration cadmium exposure and NPC progression and radiosensitivity.

Hospital-based 134 NPC cases and 132 cancer-free controls were recruited, the blood cadmium levels of whom were detected by graphite furnace atomizer absorption spectrophotometer and the basic clinical data and demographic characteristics were collected. To further confirm the effect of cadmium on NPC progression and radiosensitivity in vitro and in vivo, NPC cell lines CNE-1 and CNE-2 were continuously exposed with 1 μM cadmium chloride for 10 weeks. MTT assay, colony formation assay and xenograft tumor growth were used to assess cell viability and radiosensitivity. Transwell assays were performed to detect cell invasion and migration. The median concentration of blood cadmium in cases (3.84, IQR 2.21–6.10) was found significantly higher than that of controls (2.28, IQR 1.79–3.45) (P<0.001). Meanwhile, blood cadmium levels were positively associated with clinical stages and N classification (r=0.193, 0.187, respectively, P<0.05). MTT assay and colony formation assays showed that the cell proliferation in cadmium exposed NPC cells was significantly increased compared to the parental cells (P<0.05). Also, the invasive and migrative capacity of cadmium-treated NPC cells was markedly increased over 1.40-(P<0.01) and 1.30-(P<0.01) fold of the controls, respectively. In particular, xenograft tumours with cadmium-treated NPC cells exhibited increased tumour growth and radioresistance compared to transplanted controls(P<0.05). These results reveal the stimulative effect of chronic low-dose cadmium exposure on malignant progression and radioresistance of NPC for the first time.

 Lin Peng at the 34th International Conference of SEGH in Livingstone, Zambia

Lin Peng at the 34th SEGH International Conference in Livingstone, Zambia


 Lin Peng1,2,, Yi-Teng Huang3, Jiong-Yu Chen4*, Xia Huo5*

1 Clinical Laboratory, Cancer Hospital of Shantou University Medical College, No. 7 Raoping Road, Shantou 515041, PR China.

2 Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, No. 22 Xinling Road, Shantou 515041, PR China.

3 Health Care Center, The First Affiliated Hospital of Shantou University Medical College, Shantou 515041, PR China.

4 Oncological Research Lab, Cancer Hospital of Shantou University Medical College, No. 7 Raoping Road, Shantou 515031, PR China.

5 Laboratory of Environmental Medicine and Developmental Toxicology, Guangzhou and Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, PR, China

Keep up to date

Submit Content

Members can keep in touch with their colleagues through short news and events articles of interest to the SEGH community.

Science in the News

Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health

  • Membrane fouling control by Ca 2+ during coagulation–ultrafiltration process for algal-rich water treatment 2019-04-16

    Abstract

    Seasonal algal bloom, a water supply issue worldwide, can be efficiently solved by membrane technology. However, membranes typically suffer from serious fouling, which hinders the wide application of this technology. In this study, the feasibility of adding Ca2+ to control membrane fouling in coagulation–membrane treatment of algal-rich water was investigated. According to the results obtained, the normalized membrane flux decreased by a lower extent upon increasing the concentration of Ca2+ from 0 to 10 mmol/L. Simultaneously, the floc particle size increased significantly with the concentration of Ca2+, which leads to a lower hydraulic resistance. The coagulation performance is also enhanced with the concentration of Ca2+, inducing a slight osmotic pressure-induced resistance. The formation of Ca2+ coagulation flocs resulted in a looser, thin, and permeable cake layer on the membrane surface. This cake layer rejected organic pollutants and could be easily removed by physical and chemical cleaning treatments, as revealed by scanning electron microscopy images. The hydraulic irreversible membrane resistance was significantly reduced upon addition of Ca2+. All these findings suggest that the addition of Ca2+ may provide a simple-operation, cost-effective, and environmentally friendly technology for controlling membrane fouling during coagulation–membrane process for algal-rich water treatment.

  • Evaluation of the raw water quality: physicochemical and toxicological approaches 2019-04-13

    Abstract

    Environmental degradation has increased, mainly as a result of anthropogenic effects arising from population, industrial and agricultural growth. Water pollution is a problem that affects health, safety and welfare of the whole biota which shares the same environment. In Goiânia and metropolitan region, the main water body is the Meia Ponte River that is used for the abstraction of water, disposal of treated wastewater and effluents. In addition, this river receives wastewater from urban and rural areas. The aim in this present study was to evaluate the quality of raw water by some physical, chemical and toxicological tests. The physicochemical results found high levels of turbidity, conductivity, aluminum, phosphorus and metal iron, manganese, copper and lithium when compared to the standards of the Brazilian legislation. The values found of toxicity demonstrated a high degree of cytotoxicity and genotoxicity. Therefore, it was concluded that the Meia Ponte River has been undergoing constant environmental degradation, causing the poor quality of its waters. Thus, measures for the prevention and recovery should be adopted for the maintenance of the Meia Ponte River.

  • Review of the nature of some geophagic materials and their potential health effects on pregnant women: some examples from Africa 2019-04-11

    Abstract

    The voluntary human consumption of soil known as geophagy is a global practice and deep-rooted in many African cultures. The nature of geophagic material varies widely from the types to the composition. Generally, clay and termite mound soils are the main materials consumed by geophagists. Several studies revealed that gestating women across the world consume more soil than other groups for numerous motives. These motivations are related to medicinal, cultural and nutrients supplementation. Although geophagy in pregnancy (GiP) is a universal dynamic habit, the highest prevalence has been reported in African countries such as Kenya, Ghana, Rwanda, Nigeria, Tanzania, and South Africa. Geophagy can be both beneficial and detrimental. Its health effects depend on the amount and composition of the ingested soils, which is subjective to the geology and soil formation processes. In most cases, the negative health effects concomitant with the practice of geophagy eclipse the positive effects. Therefore, knowledge about the nature of geophagic material and the health effects that might arise from their consumption is important.