Arsenic trioxide (ATO) exhibits substantial clinical efficacy in the treatment of acute promyelocytic leukemia (APL). Here, we investigated whether ATO exerts its efficacy by affecting regulatory T (Treg) cells. We determined whether ATO treatment influenced the amount and function of purified Treg cells. We also examined the effect of ATO treatment on Treg cells from APL patients. ATO treatment induced apoptosis in purified Treg cells and dampened the inhibition of effector T (Teff) cells proliferation and the secretion of cytokine by Treg cells. Treg cell levels in the peripheral blood and serum IL-10 levels were dramatically decreased in APL patients after single ATO treatment. In summary, our results show that ATO decreases the amount and inhibits the function of Treg cells, thereby enhancing Teff cell function and overall anti-tumor immunity.

Purpose To analyze the spatial distribution characteristics and clustering of the disability-adjusted life years (DALY) rate of liver cancer in 1990 and 2017 in China based on provincial administrative divisions, and to explore its possible influencing factors, in order to provide a new scientific perspective for the prevention and control of liver cancer.Methods The DALY rate data of liver cancer at the provincial level in China were collected, the DALY rate of thematic map was segmented by natural discontinuity method, the global autocorrelation of the DALY rate was analyzed by Moran's I, the local autocorrelation of the DALY rate was analyzed by Getis-Ord-Gi*, and the influencing factors related to the DALY rate were analyzed by the least squares regression model.Results The DALY rate of liver cancer in China generally showed an increasing trend. The DALY rate of liver cancer in China increased from 649.16/100,000 in 1990 to 789.61/100,000 in 2017, increasing by 21.64%. The DALY rate increased in 22 provinces and decreased in 9 provinces. In 2017, the distribution of DALY rate in all provinces showed heterogeneity, with the highest DALY rate in Guangxi (1,363.37/100,000) and the lowest in Beijing (315.78/100,000). In 2017, the DALY rate of liver cancer in China was more extensive. The low and low clustering were mainly concentrated in Inner Mongolia and Hebei. The low and high clustering in Yunnan, Guizhou and Guangdong were surrounded by the high clustering in neighboring provinces, and the high clustering was mainly concentrated in Hunan and Jiangxi. The results of the least square regression model showed that the per capita years of education, hepatitis B incidence and the proportion of population over 65 years old had an impact on the DALY rate of liver cancer (P < 0.05). The incidence of hepatitis B and the proportion of population over 65 years old were positively correlated with the DALY rate of liver cancer, and the per capita years of education was negatively correlated with the DALY rate. GDP had no effect on the DALY rate of HCC (P > 0.05).Conclusion The DALY rate of liver cancer in China showed an overall increasing trend. In 2017, the DALY rate of liver cancer in China had a spatial aggregation in the whole country, and the per capita years of education, the incidence of hepatitis B and the proportion of population over 65 years old had an impact on the DALY rate of liver cancer in space.