[Deepening the Action on Salt Reduction in China-suggestions on strategy and implementation plan].

Excessive sodium/salt intake is the leading dietary risk factor for the loss of healthy life in the Chinese population. The "Healthy China 2030" Action Plan set the goal of reducing salt intake by 20% by 2030. However, salt intake in China is still at a very high level in the world, with adults reaching 11 g/d, more than twice the recommended limit of 5 g/d. The current policies and action plans of China have targeted catering workers, children, adolescents, and home chefs in salt, oil, and sugar reduction actions. However, there are still obvious deficiencies in the coordinated promotion and implementation. This study, therefore, proposed a set of comprehensive strategies (named CHRPS that is composed of communication and education, salt reduction in home cooking, salt reduction in restaurants, reducing salt content in pre-packaged food, and surveillance and evaluation) and key implementation points for further deepening the salt reduction action in China. These strategies were developed based on the main sources of dietary sodium for Chinese residents, the status of "knowledge, attitude and practice" in salt reduction, evidence of effective intervention measures, existing policies and requirements, and the salt reduction strategies of the World Health Organization and experience from some other countries. As a scientific reference, the CHRPS strategies will help the government and relevant organizations quickly implement salt reduction work and facilitate the earlier realization of China's salt reduction goal.

[Burden of hemorrhagic stroke and hypertensive heart disease attributed to alcohol consumption in China].

Objective: To describe the prevalence of alcohol consumption and the burden of hemorrhagic stroke and hypertensive heart disease attributed to alcohol consumption in adults aged ≥20 years in 31 provinces in China from 2005 to 2018. Methods: Data from several national representative surveys was used to estimate provincial alcohol exposure level of adults aged ≥20 years from 2005 to 2018 by using kriging interpolation and locally weighted regression methods. Global disease burden research method and data, and China's death cause surveillance data were used to calculate the population attributable fraction (PAF) of hemorrhagic stroke and hypertensive heart disease and the deaths due to alcohol consumption in men and women aged ≥20 years in 31 provinces in China. China census data of 2010 were used to calculate the attributable standardized mortality rate. Results: In 2005 and 2018, the prevalence of alcohol consumption was 58.7% (95%CI: 57.8%-59.5%) and 58.4% (95%CI: 57.6%-59.3%), respectively, in men and 17.0% (95%CI: 16.6%-17.4%) and 18.7% (95%CI:18.1%-19.3%), respectively, in women. The daily alcohol intake was 24.6 (95%CI: 23.8-25.3) g and 27.7 (95%CI: 26.8-28.7) g, respectively, in men and 6.3 (95%CI: 6.0-6.5) g and 5.3 (95%CI: 5.0-5.6) g, respectively, in women. Alcohol exposure level was higher in the provinces in central and eastern China than in western provinces. The lowest exposure level was found in northwestern provinces. From 2005 to 2018, the PAF of hemorrhagic stroke death due to alcohol consumption increased from 5.5% to 6.8%, the attributable deaths increased from 50 200 to 59 100, while the PAF of hypertensive heart disease death due to alcohol consumption increased from 7.0% to 7.7%, the attributable deaths increased from 15 200 to 29 300. The PAF of hypertensive heart disease and hemorrhagic stroke was higher in men than in women, and in central and eastern provinces than in western provinces. In 2018, the standardized mortality rates of hemorrhagic stroke and hypertensive heart disease attributed to alcohol consumption were 4.58/100 000 and 2.11/100 000, respectively. Conclusions: The prevalence of alcohol consumption in men and daily alcohol intake of drinkers were relatively high in China, especially in eastern provinces. Alcohol exposure level was lower in women than in men. Regional measures should be taken to reduce the alcohol intakes in men and current drinkers in order to reduce the health problems caused by alcohol consumption.

[Association between obesity and the prevalence of type 2 diabetes mellitus among Chinese adults aged 18-65 years in 15 provinces in 2018].

Objective: To analyze the association between different types of obesity, BMI, and waist circumference (WC) and the risk of type 2 diabetes mellitus (T2DM) in Chinese adults. Methods: Based on the China Health and Nutrition Survey data in 2018, different types of obesity were defined across different BMI and WC combinations based on Criteria of weight for adults (WS/T 428-2013), including non-obesity, simple general obesity, simple central obesity, and complex obesity. The associations of different types of obesity, BMI, and WC with T2DM risk were explored using two-level mixed-effects logistic regression and restricted cubic spline models. Results: A total of 7 030 subjects aged 18-65 were included in this study. The prevalence of general obesity and central obesity were 16.29% (502/3 082), 42.28% (1 303/3 082) in males, and 14.41% (569/3 948), 37.87% (1 495/3 948) in females. The prevalence of complex obesity was 14.70% and 12.97% in males and females, respectively. The prevalence of T2DM was 11.28% in participants, and the prevalence in complex obesity (18.98%, 22.07%) was higher than in simple central obesity (16.24%, 15.26%) and non-obesity (9.65%, 5.18%) in males and females, respectively. Multilevel regressions showed that males with simple central obesity and complex obesity had 1.61 (95%CI: 1.24-2.08) and 2.11 (95%CI: 1.56-2.86) times the odds of T2DM, respectively, as compared with the non-obesity; and the odds of T2DM in females were 2.70 (95%CI: 1.16-6.28) times for simple general obesity, 2.62 (95%CI: 2.01-3.40) times for simple central obesity, and 4.47 (95%CI: 3.35-5.98) times for complex obesity. A nearly linear positive association was observed between BMI and T2DM risk. WC was also positively associated with T2DM risk and a non-linearly increased risk in females (P for non-linear=0.024). The risk of T2DM increased when BMI ≥22.5 kg/m2 and 23.0 kg/m2, WC ≥85.0 cm and 80.0 cm in males and females, respectively. Conclusions: Complex obesity adults are more likely to suffer from T2DM. The risk of T2DM increases significantly when BMI is at the normal high values and waist circumference at the stage of pre-central obesity.

[Epidemiological characteristics and trends of cardiometabolic risk factors in residents aged 18-64 years in 15 provinces of China].

Objective: To investigate the epidemiological characteristics and trends of cardiometabolic risk factors in residents aged 18-64 years in 15 provinces (autonomous regions,municipalities) of China, and to analyze the impact of demographic characteristics on cardiometabolic risk factors. Methods: 19 827 adults aged 18-64 from the "China Health and Nutrition Survey" in 2009, 2015 and 2018 were selected as subjects. Using the data of demographic and economic factors, blood biochemical measurements and physical measurements, the trend of detection rates of metabolic risk factors in different years was analyzed by Joinpoint regression model. The association between risk factors and demographic characteristics was analyzed by multinomial logit model. Results: Among all the risk factors, overweight and central obesity had the highest detection rates (36.41% and 39.93%, respectively). In addition, among the three years, the clustering of risk factors was highest in 2015 and decreased slightly in 2018. Joinpoint regression model analysis showed that the detection rates of most metabolic risk factors expressing an overall upward trend from 2009 to 2018 but there was no significantly statistical difference in annual percentage change (APC). Among the risk factors under APC>0, the APC of obesity and diabetes was the largest (APC=5.37%, t=3.26, P=0.190; APC=5.52%, t=7.70, P=0.082), while among the risk factors with APC<0, high hs-CRP appeared as the largest (APC=-6.95%, t=-4.17, P=0.150). Multinomial logit model showed that male had higher risk of developing all metabolic risk factors than female except LDL-C, TC and hs-CRP. The risk of other risk factors except HDL-C in adults aged 45-64 years was higher than that in the younger age group aged 18-44 years, and was more significant in hypertension and elevated HbA1c, which were 4.67 (95%CI:4.07-5.37) times and 3.73 (95%CI:2.91-4.77) times of the younger age group, respectively. Residents living in the eastern areas had the highest risk of obesity, borderline high LDL-C, hypertension, elevated blood glucose and diabetes, and the lowest risk of elevated TG and high hs-CRP. People from the western region had the lowest risk of central obesity, elevated blood pressure and hypertension. Conclusions: In the three years, the detection rate and clustering of most risk factors were the highest in 2015, and there was little change in 2018. Gender, age and geographical distribution were the main influencing factors of cadiometabolic risk factors. It is suggested to adopt targeted prevention strategies and intervention measures to reduce the risk of cardiovascular disease.

[Novel vector preS1-tp fusion protein effectively inhibits hepatitis B virus replication and cccDNA synthesis by mediating hepatitis B virus targeting sequence small interfering RNA].

Objective: To study the use of preS1-tp fusion protein as a novel vector to mediate the entry of small interfering RNA (siRNA) targeting the carboxy-terminal nuclear localization signal (NLS) region of hepatitis B virus (HBV) core protein into HBV-infected hepatocytes, and to further explore the HBV replication inhibition and covalently closed circular DNA synthesis. Methods: HepG2.2.15 cells expressing the human sodium taurocholate co-transporting polypeptide were established on the basis of lentivirus infection system. siRNA against HBV NLS region was designed and synthesized. PreS1-tp fusion protein expression and purification was observed to test its ability to cell entry and DNA binding. NLS siRNA were delivered into HepG2.2.15- sodium taurocholate co-transporting polypeptide cells by preS1-tp fusion protein as a vector to observe the effects of NLS siRNA on HBV replication and covalently closed circular DNA levels. Analysis of variance was used for comparison between multiple groups, and the measurement data differences between groups were analyzed by t-test. Results: HepG2.2.15-sodium taurocholate co-transporting polypeptide cell line was successfully constructed. Screened synthetic HBV NLS siRNA had significantly inhibited HBV replication. The preS1-tp fusion protein was expressed and purified on a large-scale. The fusion protein as a vector for HBV NLS siRNA had targeted delivery. The result showed that the fusion protein had effectively targeted siRNA to Hepg2.2.15-sodium taurocholate co-transporting polypeptide cell, which not only had effectively inhibited the expression of HBV mRNA, HBsAg and HBeAg, but also had significantly reduced the levels of HBV DNA and covalently closed circular DNA. Conclusion: The preS1-tp fusion protein constructed in this study uses the dual functional characteristics of preS1 binding to hepatocyte HBV receptor, and tp binding to nucleic acids, and targets HBV NLS siRNA against HBV-infected cells and block rcDNA from being transported to nucleus. siRNA plays a role in inhibiting HBV replication and covalently close circular DNA synthesis, providing a new strategy for the treatment of chronic hepatitis B caused by HBV infection, and a new research perspective for the complete elimination of HBV from the body.

[Analysis of clinical characteristics of 49 cases of COVID-19].

Objective: To analyze the epidemiological and clinical characteristics, and imaging features of patients with COVID-19 in Henan Province People's Hospital. Methods: The epidemiology, clinical symptoms, laboratory and radiologic data of 49 patients with COVID-19 infection admitted to the department of infectious disease in our hospital from January 23, 2020 to February 22, 2020 were retrospectively analyzed. All analyses were performed with SPSS software, version 22.0. Results: A total of 49 patients with COVID-19 were enrolled, of which 28 were ordinary, 16 were severe, and 5 were critical in disease severity. The average ages of the 3 groups were (46±19) , (60±16) and (68±20) years, with statistical differences (P=0.015). Common symptoms at the onset were fever (41 patients), dry cough (35 patients), and fatigue (21 patients). Epidemiological investigations found that 31 (63%) patients had direct or indirect contact with confirmed cases, and 14 cases were family clustered. Laboratory test results showed that the lymphocyte counts progressively decreased [0.85 (0.5-1.6) ×10(9)/L,0.51 (0.4-0.9) ×10(9)/L and 0.43 (0.47-0.61) ×10(9)/L, respectively], while LDH [162 (145.1-203.5) U/L,265 (195.3-288.4) U/L and 387 (312.3-415.5) U/L, respectively] and D-dimer [0.15 (0.09-0.40) mg/L,0.4 (0.2-0.6) mg/L and 0.9 (0.5-1.4) mg/L, respectively] were significantly increased (P<0.05), in all the 3 groups. The levels of IL-6 [(43.2±15.4) µg/L, (78.5±31.2) µg/L and (132.4±47.9) µg/L, respectively] and IL-10 [(3.5±3.2) µg/L, (7.6±6.4) µg/L and (9.4±7.2) µg/L respectively] increased significantly with disease severity. Pulmonary imaging of ordinary patients mainly showed unilateral or bilateral multiple infiltrates, while severe and critically ill patients showed diffuse exudation and consolidation of both lungs, and a few patients showed signs of "white lungs". Conclusions: Patients with COVID-19 has a definite history of contact with diagnosed patients, and has family aggregation. The clinical symptoms were mainly fever and dry cough. Laboratory results showed that lymphocyte count, LDH, D-dimer, interleukin-6 and interleukin-10 levels had a significant correlation with the severity of the disease, which could be used as markers for disease progression and prognosis. Pulmonary imaging showed unilateral or bilateral ground glass infiltration. In severe and critically ill patients, diffuse infiltration and consolidation or even "white lung" were present.

[Introduction to Guidelines for Salt Reduction in Chinese Food Industry].

Excessive salt intake is an important risk factor of diseases such as hypertension, stroke, and stomach cancer. China is one of countries with high salt intake in the world. Recently, the intake of sodium from pre-packaged foods in China has been increasing, and the situation of salt control is rigorous. Based on the summary of the domestic and international experience of salt reduction, the "Guidelines for Salt Reduction in Chinese Food Industry" presents the basic principles, targets at different stages within various categories, technical routes, steps and measures, and social environment co-construction of salt reduction in Chinese food industry. This article focuses on the background, basis, process, key content and promotion of the guideline. The implementation of this guideline will contribute to the vigorous advancement of salt reduction action in Chinese food industry.

[Enhancing nutrition and health survey and implementing effective interventions to reduce the incidence of nutritional diseases].

Public nutrition is related to the improvement of population health and the development of social economy. Nutrition and health survey can provide indispensable information for public health and disease prevention and control to improve people's nutritional and health status and support the policy making of food production and chronic diseases prevention and control. In recent years, China's nutritional supply capacity has increased significantly. Our people's nutritional and health status has improved significantly. The articles published in "Nutrition and Health Survey" column come from nutrition surveys both at the national and provincial level. They are making full use of data to give information on not only nutritional and health status of residents throughout the country, but also regional features. These results will provide a detailed and reliable reference for both national and regional nutrition and health policy and strategy making. At present, China's nutrition work faces many challenges. China's Party Central Committee and the State Council always places great emphasis on people's nutritional and health status. In order to promote the health of the whole population in our country, our government has implemented a number of nutrition promotion policies or strategies. Chinese nutrition and health survey will further evaluate the effect of these movements.

[Relationship between meat consumption and metabolic syndrome in adults in China].

Objective: To explore the relationship between meat consumption and metabolic syndrome (MS) in Chinese adults aged ≥18 years. Methods: The data were obtained from 2010- 2012 National Nutrition and Health Survey. A total of 34 923 subjects who completed the dietary survey, the physical examination and had the testing results of blood sugar and blood lipid levels were enrolled in this study. MS was defined according to the diagnostic criteria of China Diabetes Society 2013. The prevalence ratios of MS and each form of MS and related 95%CI were calculated after post stratification weight according to the population data (2009) released by the national bureau of statistics. Results: The average meat intake among subjects was 94.8 g/d. People who had meat consumption between 100 g/d and 199 g/d had the lowest prevalence of MS, abdominal obesity and hyperglycemia. As the meat consumption increased, the prevalence of MS in men increased. Men who had meat consumption of ≥300 g/d had a higher risk of MS than those who had low level of meat consumption, with prevalence ratio equaled to 1.46 (95%CI: 1.14~1.87). Similar trend was not observed in women. Conclusion: Moderate intake of meat is associated with reduced risk of MS in Chinese adults.

[The drinking status and associated factors in adults in China].

Objective: To investigate the drinking status and associated factors in adults in China. Methods: Based on the 2010-2012 China National Nutrition and Health Survey (CNNHS), a total of 135 824 participants aged ≥18 were included in this cross-sectional analysis. Multivariable logistic regression model was used to investigate the associated factors for drinking status. Results: The overall drinking rate was 30.5% in Chinese adults, 53.8% in men, and 12.2% in women. The excessive drinking rate was 14.0% in men and 1.1% in women. The daily drinking rate was 25.7% in men and 10.9% in women. Men mainly consumed multi-type wines, but women preferred beer. The overall harmful drinking rate was 7.1%. The excessive drinking rate, daily drinking rate, and harmful drinking rate increased first but then declined with age. All the four rates were positively related with physical activity. Conclusions: The drinking rate, excessive drinking rate, daily drinking rate and harmful drinking rate were high in adults in China. Drinking status was associated with age, sex, marital status, education level, smoking status and physical activity.

[Prevalence of cardio metabolic risk factors and related socio-demographic factors in adults aged 18-59 years in 15 provinces of China].

Objective: To analyze the prevalence and co-prevalence of cardio metabolic (CM) risk factors in adults in China. Methods: The project data of 2015 Nutritional Status and Health Transition of Chinese Residents were used, and 5 456 adults aged 18-59 years with complete socio-demographic, anthropometric, and blood biochemical data were selected as the study subjects. The definition released by the International Diabetes Federation in 2005 were used to define each CM risk factors, including central obesity, elevated TG, reduced HDL-C, elevated blood pressure and elevated FPG. The co-prevalence of the risk factors was defined as adults having ≥2 risk factors. Multivariable logistic regression analysis was performed to evaluate the relationship between CM risk and socio-demographic factors. Results: About 80.8% of adults had at least 1 risk factor, and 54.0% had co-prevalence of risk factors. Gender, age, education level and living area were significantly associated with the prevalence of major metabolic risk factors. After adjusting for other factors, compared with men, women were more likely to have central obesity and reduced HDL-C, but not more likely to have elevated blood pressure, elevated FPG and elevated TG (P<0.01). Compared with adults aged 18-44 years, adults aged 45-59 years were more likely to have central obesity, elevated blood pressure, elevated FPG and elevated TG (P<0.01). The odds of having central obesity, elevated blood pressure and elevated fasting plasma glucose in the adults in eastern China were significantly higher than those in the central and western China. Conclusions: In 2015, less than 20% of the adults aged 18-59 years in China had no cardio metabolic risk factors, and more than half of them had two or more risk factors. Gender, age and living areas were the major influencing factors. It is necessary to take effective intervention measures targeting adults at high-risk for the early prevention of cardiovascular disease.

[The epidemic status of metabolic syndrome among Chinese adolescents aged 10-17 years in 2010-2012].

Objective: To invesigate the epidemic status of the metabolic syndrome (MS) among mainland Chinese adolescents aged 10-17 in 2010-2012. Methods: Data were collected from Chinese Nutrition and Health Surveillance in 2010-2012. Multi-stage stratified proportion to the population cluster random sampling method was conducted to determine 16 872 adolescents in 150 counties from 31 provinces in mainland China. The epidemic status of metabolic syndrome was analyzed by China criterion (defined by Chinese Pediatric Society, Chinese Medical Association) and Cook criterion, respectively. The prevalence of MS and 95%CI were calculated through weighted complex sampling processing by population data released by the National Bureau of Statistics in 2009. Results: Based on China criterion, the weighted prevalence of MS was 2.4% (95% CI: 2.1%-2.6%) among Chinese adolescents aged 10-17. Prevalence in urban was higher than in rural (2.8%, 95%CI: 2.4%-3.2% and 1.9%, 95%CI:1.6%-2.3%, respectively). Prevalence in boys and girls were 2.7% (95% CI: 2.3%-3.0%), and 2.0% (95% CI: 1.7%-2.4%), respectively. Based on Cook criterion, the weighted prevalence was 4.3% (95% CI: 4.0%-4.7%) . The highest weighted prevalence of the components of the metabolic syndrome was low high-density lipoprotein cholesterol (26.8%, 95% CI: 26.0%-27.5%), followed by high fasting glucose (11.5%, 95% CI: 11.0%-12.0%), abdominal obesity (11.1%, 95%CI: 10.6%-11.7%) , hypertriglyceridemia (8.8%, 95%CI: 8.4%-9.3%) , and high blood pressure (6.4%, 95% CI: 6.0%-6.8%). Conclusion: Among the five indicators of metabolic syndrome, the prevalence of central obesity and hypertriglyceridemia were relative high in Chinese adolescents aged 10-17 years, though the prevalence of metabolic syndrome was not high.

[Value of thromboelastography in evaluating coagulation function and prognosis in patients with acute-on-chronic liver failure].

Objective: To investigate the coagulation function in patients with acute-on-chronic liver failure (ACLF) patients using thromboelastography (TEG), and to comprehensively and dynamically evaluate patients' bleeding and coagulation status. Methods: The clinical data of ACLF patients were collected, and TEG was used to evaluate whole blood clotting kinetics in these patients. Routine biochemical parameters were measured, and complications were evaluated. The t-test was used for comparison of continuous data, the chi-square test was used for comparison of categorical data, and the Pearson correlation coefficient was used for correlation analysis. P < 0.05 was considered statistically significant. Results: A total of 60 patients (39 male and 21 female patients) were enrolled, with a mean age of 47.20±16.20 years. The TEG results showed that all patients had normal thrombokinetics, but TEG parameters were correlated with coagulation function, markers of systemic inflammatory response syndrome, laboratory markers, and prognosis. The patients with a higher R value had higher risks of infection (6.23±2.91 vs 4.74±1.12, P = 0.009), hepatorenal syndrome (5.64±2.54 vs 3.21±1.43 P < 0.01), and bleeding (6.71±3.51 vs 4.80±1.63, P = 0.01), and the patients with a lower K value (0.72±1.36 vs 1.64±1.43, P = 0.02), an increased α-angle (63.33°±10.02° vs 56.62°±12.13°, P = 0.03), and an increased MA (56.83±11.07 vs 50.40±10.81, P = 0.03) had increased risks of hepatic encephalopathy. Conclusion: ACLF patients have low coagulation function, and TEG truly reflects the "rebalance" status of this low level. Abnormal TEG parameters suggest increased risk of complications in these patients, indicating a poor prognosis.

[Prevalence of metabolic syndrome in Chinese adults in 2010-2012].

Objective: To estimate the prevalence and distribution of metabolic syndrome (MS) in Chinese adults. Methods: Cross-sectional data on 104 098 men and women aged 18 years or above was gathered from 150 monitoring sites from 31 provinces, autonomous regions, and municipalities from the China National Health and Nutrition Surveillance (2010-2012) Project. Data was randomly selected by multi-stage stratified and Probability Proportionate to Size (PPS) cluster random sampling method. Prevalence of MS was defined under the diagnostic criteria of China Diabetes Society (CDS). Complex sampling weighing method was used with demographic data released by the National Bureau of Statistics of China in 2009, when calculating the prevalence and its 95%CI of MS. Results: The overall prevalence rate of the MS among adults was 11.0%, more seen in urban than in rural areas, and in men than in women. The prevalence showed a parallel increasing trend with age. As was observed in the comparison between the prevalence of four components of MS, the prevalence rates of dyslipidemia (33.7%) and overweight or obesity (32.3%) showed more serious than in hypertension (22.4%) or hyperglycemia (16.2%). Conclusion: The prevalence of MS among adults in China showed an increasing trend which had already become a significant public health problem, in the country.

[Influence of diet and behavior related factors on the peripheral blood triglyceride levels in adults: a cross-sectional study].

Objective: To study the influence of diet and behavior related factors on the peripheral blood triglyceride levels in adults, through a cross-sectional survey. Methods: The current study included 13 434 subjects without histories of major chronic diseases from a population-based cross-sectional survey: the 2010 Metabolic Syndrome Survey in Zhejiang Province. A generalized linear model was used to investigate the influence of diet/behavior-related factors on the peripheral blood triglyceride levels. Results: Mean TG of the sample population appeared as (1.36±1.18) mmol/L. The proportions of elevated TG and marginally elevated TG were 10.3% and 11.0% respectively, with statistically significant difference seen between males and females (χ(2)=44.135, P<0.001). In this sampled population, the daily intake of cooking oil was exceeding the recommendation levels by over 50% while the intake of fruit, milk, nuts and physical exercise were much below the recommendation. There were statistically significant differences between smoking, alcohol-intake, meat, fruit and water intake in male population from this study. However, in females, the intake of aquatic product and physical exercise showed statistically significant differences. After controlling for other variables, factors as age, drinking, staple food and aquatic products showed positive influence on TG, while milk presented negative influence on TG. Through interaction analysis, fruit and meat intake in males and staple food in females showed positive influence on TG, when compared to the reference group. Conclusion: Hyperglyceridemia appeared as one of the major metabolic abnormities in Zhejiang province. Programs on monitoring the alcohol, staple food and meat intake should be priority on intervention, in the communities.

[Hepatitis B core antigen promotes invasion of hepatocellular carcinoma cell line HepG2.2.15 via Toll-like receptor 4].

Objective: To investigate the effect of hepatitis B core antigen (HBcAg) in promoting the invasion of hepatitis B virus (HBV)-related hepatocellular carcinoma cell line HepG2.2.15 and the role of Toll-like receptor 4 (TLR4) in the mechanism. Methods: TLR4 mRNA and protein expression in HepG2 cells and HepG2.2.15 cells was measured by reverse transcription real-time PCR and Western blot analysis, respectively. HepG2.2.15 cells were transfected with TLR4 specific small interfering RNA (siRNA) to silence TLR4 expression, and stimulated by recombinant HBcAg in culture. The invasion of cells was measured by Transwell invasion assay. The expression of TLR4 signaling pathway-related proteins in the cultured cells and proinflammatory cytokines in the supernatant was also determined. The student's t-test, one-way ANOVA, and SNK-q test were used for statistical analysis. Results: TLR4 mRNA and protein expression in HepG2.2.15 cells was significantly higher than that in HepG2 cells. TLR4 siRNA transfection remarkably down-regulated TLR4 expression in HepG2.2.15 cells. Inhibiting TLR4 expression and/or HBcAg stimulation did not affect the proliferation of HepG2.2.15 cells. However, HBcAg stimulation significantly increased the invasion ability of HepG2.2.15 cells and the secretion of proinflammatory cytokines [including interferon (IFN)-γ, interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α]. Inhibiting TLR4 expression significantly reduced HBcAg-induced cellular invasion. Meanwhile, HBcAg stimulation elevated the expression of MyD88 and TRIF in HepG2.2.15 cells. TLR4 silencing inhibited HBcAg-induced increase in the expression of MyD88, while it showed no significant impact on TRIF expression. Conclusion: HBcAg can promote the invasion of HepG2.2.15 cells. The TLR4/MyD88 signaling pathway may be involved in this process by inducing the expression of proinflammatory cytokines.