Chen W

Prospective study of serum 25(OH)-vitamin D concentration and risk of oesophageal and gastric cancers.

We prospectively examined the relation between pretrial serum vitamin D status and risk of oesophageal and gastric cancers among subjects who developed cancer over 5.25 years of follow-up, including 545 oesophageal squamous cell carcinomas (ESCC), 353 gastric cardia adenocarcinomas, 81 gastric noncardia adenocarcinomas, and an age- and sex-stratified random sample of 1105 subjects. The distribution of serum 25(OH)D was calculated using the known sampling weights. For the cohort as a whole, the 25th, 50th, and 75th percentile concentrations of 25(OH)-vitamin D were 19.6, 31.9, and 48.7u2009nmolu2009l−1, respectively, and we found that higher serum 25(OH)D concentrations were associated with monotonically increasing risk of ESCC in men, but not in women. Comparing men in the fourth quartile of serum 25(OH)D concentrations to those in the first, we found a hazard ratio (HR) (95% confidence interval (CI)) of 1.77 (1.16–2.70), P trend=0.0033. The same comparison in women had a HR (95% CI) of 1.06 (0.71–1.59), P trend=0.70. We found no associations for gastric cardia or noncardia adenocarcinoma. Among subjects with low vitamin D status, higher serum 25(OH)D concentrations were associated with significantly increased risk of ESCC in men, but not in women. Further refinements of the analysis did not suggest any factors, which could explain this unexpected result.

Relationship between cancer mortality/incidence and ambient ultraviolet B irradiance in China

BackgroundStudies finding an inverse correlation of ambient solar irradiance with cancer mortality were the first to suggest that sun exposure and probably, therefore, vitamin D might protect against some cancers. Such correlation has been shown in Asian populations in some studies. We analyzed the correlation between mortality and incidence from a number of cancers and ambient solar ultraviolet (UV) B irradiance in China.MethodsCancer mortality data were obtained from the Second National Death Survey conducted in a sample of 263 counties in China from 1990 to 1992. National cancer registration data 1998–2002 in China were used for estimation of cancer incidence. Satellite measurements of cloud-adjusted ambient UVB intensity at 305xa0nm were obtained from a NASA database and GIS methods used to estimate the average daily irradiance for the 263 counties in 1990. We estimated cancer mortality rate ratios per 10 mW/(nmxa0m2) change in UVB by fitting a negative binomial regression model with mortality as the response variable and UVB as the independent variable, adjusted for sex, age, and urban or rural area.ResultsMortality rates for all cancers and cancers of the esophagus, stomach, colon and rectum, liver, lung, breast, and bladder were inversely correlated with ambient UVB. This correlation was present in men and women and rural residents for all these cancers but not urban residents for cancers of the esophagus, colon and rectum and liver. Lung cancer mortality showed the strongest inverse correlation with an estimated 12% fall per 10 mW/(nmxa0m2) increase in UVB irradiance even if adjusted for smoking. Only incidence rates for cancers of the esophagus, stomach, colon and rectum and cervix were inversely correlated with ambient UVB. Mortality and incidence from nasopharyngeal cancer increased with increasing UVB [respectively 27 and 12% per mW/(nmxa0m2)]. Mortality from cancer of the cervix also increased, but to a lesser extent and mortality from leukemia was not consistently correlated with UVB irradiance.ConclusionMortality from all cancers together and most major cancers in China was inversely associated with solar UVB. These associations were similar to those observed in a number of populations of European origin. Incidence of some cancer types had the same correlation with UVB. They suggest the possibility that vitamin D may reduce the incidence or improve the outcome of cancer in Chinese people.

Evaluation on the incidence, mortality and tendency of lung cancer in China

Objective:u2002 To analyze lung cancer epidemiological trends and estimate the lung cancer burden in China.

Attributable causes of cancer in China

BACKGROUNDnMost cancers are due to modifiable lifestyle and environmental risk factors, and are potentially preventable. No studies have provided a systematic quantitative assessment of the burden of cancer mortality and incidence attributable to known risk factors in China.nnnMETHODSnWe calculated the proportions of cancer deaths and new cases attributable to known risk factors in China, based on the prevalence of exposure around 1990 and national data on cancer mortality and incidence for the year 2005.nnnRESULTSnChronic infection is the main risk factor for cancer in China, accounting for 29.4% of cancer deaths (31.7% in men and 25.3% in women), followed by tobacco smoking (22.6% with 32.7% in men and 5.0% in women), low fruit intake (13.0%), alcohol drinking (4.4%), low vegetable intake (3.6%) and occupational exposures (2.7%). The remaining factors, including environmental agents, physical inactivity, the use of exogenous hormones and reproductive factors are each responsible for <1.0%.nnnCONCLUSIONSnModifiable risk factors explain nearly 60% of cancer deaths in China, with a predominant role of chronic infection and tobacco smoking. Our findings could provide a basis for cancer prevention and control programs aimed at reducing cancer risk in other developing countries.BACKGROUNDnMost cancers are due to modifiable lifestyle and environmental risk factors, and are potentially preventable. No studies have provided a systematic quantitative assessment of the burden of cancer mortality and incidence attributable to known risk factors in China.nnnMETHODSnWe calculated the proportions of cancer deaths and new cases attributable to known risk factors in China, based on the prevalence of exposure around 1990 and national data on cancer mortality and incidence for the year 2005.nnnRESULTSnChronic infection is the main risk factor for cancer in China, accounting for 29.4% of cancer deaths (31.7% in men and 25.3% in women), followed by tobacco smoking (22.6% with 32.7% in men and 5.0% in women), low fruit intake (13.0%), alcohol drinking (4.4%), low vegetable intake (3.6%) and occupational exposures (2.7%). The remaining factors, including environmental agents, physical inactivity, the use of exogenous hormones and reproductive factors are each responsible for <1.0%.nnnCONCLUSIONSnModifiable risk factors explain nearly 60% of cancer deaths in China, with a predominant role of chronic infection and tobacco smoking. Our findings could provide a basis for cancer prevention and control programs aimed at reducing cancer risk in other developing countries.

Akt/Ezrin Tyr353/NF-κB pathway regulates EGF-induced EMT and metastasis in tongue squamous cell carcinoma.

Background:Epithelial–mesenchymal transition (EMT) is a crucial programme in cancer metastasis. Epidermal growth factor (EGF) is a key inducer of EMT, and Ezrin has an important role in this process. However, how Ezrin is activated and whether it mediates EGF-induced EMT in tongue squamous cell carcinomas (TSCCs) through activating NF-κB remains obscure.Methods:We used two TSCC cell lines as a cell model to study invasion and EMT in vitro, and used nude mice xenografts model to evaluate metastasis of TSCC cells. Finally, we evaluated the level of pEzrin Tyr353, nuclear p65 and EMT markers in TSCC clinical samples.Results:Ezrin Tyr353 was phosphorylated through Akt (but not ERK1/2, ROCK1) pathway, and lead to the activation of NF-κB in EGF-treated TSCC cells. Akt and NF-κB inhibitors blocked EGF-induced EMT, and suppressed invasion and migration of TSCC cells. In vivo, silencing Ezrin significantly suppressed EGF-enhanced metastasis of TSCC xenografts. Finally, high levels of expression of pEzrin Tyr353, nuclear p65, vimentin and low level of expression of E-cadherin were correlated with cancer metastasis and poor patient prognosis.Conclusion:Our data suggest that Akt/Ezrin Tyr353/NF-κB pathway regulates EGF-induced EMT and metastasis inTSCC, and Ezrin may serve as a therapeutic target to reverse EMT in tongue cancers and prevent TSCC progression.

Time Trends of Ovarian Cancer Incidence in China

The aim of this study was to examine the trend of ovary cancer incidence from 1999 to 2010 in China and predict the burden up to 2020. Crude incidence, age specific incidence and age-adjusted incidence rates were calculated. Joinpoint regression was performed to obtain estimated annual percentages and Bayesian age-period- cohort modeling was used to predict the incidence rate until the year 2020. In China, the crude rate of ovary cancer was 7.91/100,000 and the age-adjusted rate was 5.35/100,000 overall during period 1999-2010. The rates in urban regions were higher than in rural regions. A significant rising trend during 1999-2006 was followed by a drop during 2006-2010 in age-adjusted rates for urban females. In contrast, constant rise was observed in rural women. The decrease in ovary cancer of urban areas tended to be restricted to women aged 50 years and younger. In contrast, increases of ovary cancer in rural areas appeared in virtually all age groups. Although the age-adjusted incidence rate for ovary cancer was predicted to be reduced after year 2011, the crude rate was likely to be relative stable up to 2020. The burden of ovary cancer in China will continue to be relative stable due to the aging population.

Association between serum 25(OH) vitamin D, incident liver cancer and chronic liver disease mortality in the Linxian Nutrition Intervention Trials: a nested case-control study.

Background:Although vitamin D deficiency has been noted in cross-sectional studies of chronic liver disease and laboratory studies suggest possible benefits of vitamin D in preventing liver cancer, little epidemiologic data are available.Methods:We performed a nested case–control study in the Linxian Nutrition Intervention Trials on participants developing incident liver cancer or dying from chronic liver disease over 22 years of follow-up. Baseline serum 25(OH) vitamin D was measured for 226 incident liver cancer cases, 282 chronic liver disease deaths and 1063 age-, sex- and trial-matched controls. Unconditional logistical regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).Results:The median serum vitamin D level in controls was low (20u2009nmolu2009l–1). Compared with the lowest quartile, subjects in the fourth quartile had lower risk of chronic liver disease death (OR=0.34, 95% CI=0.21–0.55). For liver cancer incidence, risk estimates were below one, but were not statistically significant. Associations, however, were significant among participants with higher serum calcium levels (Q4 vs Q1, OR=0.43, 95% CI=0.21–0.89). Results for chronic liver disease did not vary by serum calcium level.Conclusion:In a low vitamin D population, higher serum 25(OH) vitamin D concentrations were associated with significantly lower risk of chronic liver disease deaths, and among those with higher serum calcium, incident liver cancer. Our results suggest a possible protective role for vitamin D in these diseases.

Colorectal Cancer Incidence and Mortality in China, 2010

BACKGROUNDnThe National Central Cancer Registry of China (NCCR) affiliated to the Bureau of Disease Control, National Health and Family Planning Commission of China is responsible for cancer surveillance in the entire country. Cancer registration data from each local registry located in each province are collected by NCCR annually to be analyzed and published to provide useful information for policy makers and cancer researchers.nnnMATERIALS AND METHODSnUntil 1st June, 2013, 219 population-based cancer registries submitted data of 2010 to the National Central Cancer Registry of China covering about 207,229,403 population, and 145 cancer registries were selected after quality evaluation for this study. Colorectal cancer cases were selected from the database according to ICD-10 coded as C18-C20. We calculated the crude incidence and mortality rates by sex, age groups and location (urban/rural). The China population in 2000 and Segis population were used as standardized populations for the calculation of age-standardized rates. The 6th National Population Census data of China was used to combined with the cancer registries data to estimate the colorectal cancer burden in China in 2010.nnnRESULTSnColorectal cancer was the sixth most common cancer in China. It was estimated that there were 274,841 new cases diagnosed in 2010 (157,355 in males and 117,486 in females), with the crude incidence rate of 20.1/100,000, highest in males in urban areas. Age-standardized rates by China standard population of 2000 (ASRcn) and World standard population (Segis population, ASRwld) for incidence were 16.1/100,000 and 15.9/100,000 respectively. There were 132,110 cases estimated to have died from colorectal cancer in China in 2010 (76,646 men and 55,464 women) with the crude mortality rate of 10.1/100,000. The ASRcn and ASRwld for mortality were 7.55/100,000 and 7.44/100,000 respectively, higher in males and urban areas than in females and rural areas. The incidence and mortality rates increased with age, reaching peaksin the 80-84 year old, and oldest age groups, respectively.nnnCONCLUSIONSnColorectal cancer is one of the most common incident cancers and cause of cancer death in China. Primary and secondary prevention, with attention to a health lifestyle, physical activity and screening should be enhanced in the general population.

Dietary factors and smoking as risk factors for PD in a rural population in China: a nested case–control study

Backgroundu2002–u2002 Dietary factors and history of smoking remain elusive in the pathogenesis of Parkinsons disease (PD).

Lung cancer incidence and mortality in China, 2009: Lung cancer statistics, China 2009

The National Central Cancer Registry (NCCR) is a governmental organization for cancer surveillance affiliated to the Bureau of Disease Control, Ministry of Health, in China. It annually collects cancer registration data from local registries and then analyzes and publishes the results to provide useful information for making anti‐cancer policy, program evaluation, and etiology research. At the end of 2012, the NCCR reported cancer statistics for 2009.