Methylation Status of Transcriptional Modulatory Genes Associated with Colorectal Cancer in Northeast China

BACKGROUND/AIMS: Methylation status plays a causal role in carcinogenesis in targeted tissues. However, the relationship between the DNA methylation status of multiple genes in blood leukocytes and colorectal cancer (CRC) susceptibility as well as interactions between dietary factors and CRC risks are unclear. METHODS: We performed a case-control study with 466 CRC patients and 507 cancer-free controls to investigate the association among the methylation status of individual genes, multiple CpG site methylation (MCSM), multiple CpG site heterogeneous methylation and CRC susceptibility. Peripheral blood DNA methylation levels were detected by performing methylation-sensitive high-resolution melting. RESULTS: Total heterogeneous methylation of CA10 and WT1 conferred a significantly higher risk of CRC (adjusted odds ratio [OR(adjusted)], 5.445; 95% confidence interval [CI], 3.075 to 9.643; OR(adjusted), 1.831; 95% CI, 1.100 to 3.047; respectively). Subjects with high-level MCSM (MCSM-H) status demonstrated a higher risk of CRC (OR(adjusted), 4.318; 95% CI, 1.529 to 12.197). Additionally, interactions between the high-level intake of fruit and CRH, WT1, and MCSM on CRC were statistically significant. CONCLUSIONS: The gene methylation status of blood leukocytes may be associated with CRC risk. MCSM-H of blood leukocytes was associated with CRC, especially in younger people. Some dietary factors may affect hypermethylation status and influence susceptibility to CRC.

Association of catalase genotype with oxidative stress in the predication of colorectal cancer: modification by epidemiological factors / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>This paper aims to assess the interaction between common variations in catalase (CAT) polymorphic gene and environmental factors for antioxidant defense enzyme in modulating individual susceptibility to colorectal cancer (CRC).</p><p><b>METHODS</b>A case-control study with 880 colorectal cancer cases and 848 controls was conducted to investigate whether variations in the catalase (CAT) gene, one of the genes involved in scavenging oxidative stress, influenced susceptibility to CRC.</p><p><b>RESULTS</b>The interaction between life style and genotypes as well as with their effects on colorectal cancer was deduced from the present study. Significant difference (P = 0.01) was identified in the distribution of CAT genotype between the colorectal cancer cases and the controls. The CRC cases had significantly lower mean activity than the controls (P < 0.01). Correlation analyses revealed statistically significant correlations between CAT activity and CAT genotype (P < 0.01).</p><p><b>CONCLUSION</b>The risk of CRC was associated with smoking, low vegetable consumption, high pork and poultry consumptions, and low or high BMI. This is the first study reporting an association of polymorphism CAT-21A > T with colorectal cancer. Low CAT activity was associated with an increased risk of CRC; however, no evidence was found to support an association between CAT-21A > T polymorphism and CRC risk.</p>

A comparative study on the prevalence of osteoarthritis in middle and old-aged people from the urban and the rural area in Heilongjiang province / 中华流行病学杂志

Objective To investigate the prevalence of osteoarthritis in inhabitants aged 40 years old and above from urban and rural areas in Heilongjiang province. Methods Through multistage stratified cluster random sampling methods, residents aged 40 years and above were selected. All subjects were given a standardized questionnaire and were conducted a radiographic examination on hands, knees, neck spine and lumbar spine after informed consent. All statistics were performed by SPSS13.0. Results A total of 1196 residents were surveyed, which including 573 males and 623 female subjects. The prevalence of osteoarthritis in cervical spine, lumbar spine, knee and hand for men were 26.00%, 31.20%, 11.87%, 15.53%, respectively and that were 34.80%, 30.20%, 20.06%, 27.93% for women respectively. The prevalence of osteoarthritis increased with aging both in men and women. Prevalence in 60-70 age group achieved the peak. The prevalence rates became relatively low among those over the 70 years old than expected. The most common sites of osteoarthritis were knees and hands (16.10%), followed by cervical and lumbar spine (12.40%).Conclusion The prevalence of osteoarthritis was generally high in middle and old-aged people in Heilongjiang province.

Evaluation of oxidative stress in colorectal cancer patients / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To evaluate the oxidative stress in patients with colorectal cancer and to investigate the relationship between oxidative stress and colorectal cancer.</p><p><b>METHODS</b>Seventy-six subjects were divided into two groups (36 colorectal cancer patients as the study group and 40 normal healthy individuals as the control group). Their protein oxidation, DNA damage, lipid peroxidation and antioxidants, vitamin C, vitamin E, glutathione (GSH), and antioxidative enzymes in serum were detected.</p><p><b>RESULTS</b>The levels of protein carbonyl and advanced oxidation protein products (AOPP) were significantly higher in the study group than in the control group (P<0.01). Serum 8-OHdG was significantly increased in the study group compared to the control group (P<0.01). However, the mean serum level of MDA and conjugated diene was lower in the study group than in the control group (P<0.01). The activity of antioxidative enzymes was significantly decreased in the study group compared to the control group (P<0.01). Serum vitamins C and E concentrations were significantly reduced in the study group compared to the control group (P<0.01).</p><p><b>CONCLUSION</b>Colorectal cancer is associated with oxidative stress, and assessment of oxidative stress and given antioxidants is important for the treatment and prevention of colorectal cancer.</p>

Awareness on SARS and public health emergencies among general publics / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the awareness on sever acute respiratory syndrome (SARS) and public health emergencies among general publics.</p><p><b>METHODS</b>A cluster sampling method was implemented in Harbin and Jiagedaqi district of Daxinanling of Heilongjiang province. Research subjects were divided into three groups as city, township and rural areas and were given questionnaires to fill in. Data was analyzed with Epi-data and SPSS.</p><p><b>RESULTS</b>2003 available questionnaires were collected. The general publics well understood the knowledge on public health emergencies and the SARS with the whole recognition rate more than 60 percent. During the epidemics, people in city, town and countryside were calm (71.7%). The rates of attitude towards the government were significantly different among the subjects living with the city, town or rural areas. The city group expressed the highest favor to the government and media, 71.8% of them gave the credit on the control of SARS to the effective method taken by the government and 65.0% of them showed that they had enough confidence on the governmental ability of dealing with crises while the countryside group trusted the hospitals and relative specialists the most.</p><p><b>CONCLUSION</b>It is essential for the government to interact and communicate with the publics through media, medical and related institutions when confronting with the public health emergencies. Publicity on health knowledge and coping system on emergency should play key roles in the development of an effective public health system while the government should lead the battle.</p>