ObjectiveTo analyze the epidemiological burden and trend of skin malignant melanoma in China based on the data from the global burden of disease 2019 (GBD 2019). MethodsThe data about quantity of incidences/illnesses/deaths, age-standardized incidence/prevalence rates/mortality, disability-adjusted life years (DALYs), and DALY rate of skin malignant melanoma in China from 1990 to 2019 were obtained from the GBD 2019 databases. The epidemiological trends, age-period-cohort trends, and the relationship between the incidence and sociodemographic index (SDI) were analyzed.ResultsIn 2019, both prevalence and incidence of skin malignant melanoma in China were at low levels in the world, the age-standardized mortality ranked the 35th in the 204 countries GBD researched, the number of prevalent cases and incident cases increased compared with 1990 (12.65% and 3.57%, respectively), the prevalence and incidence rates showed growth trends, while the DALY rate and mortality decreased slowly. The prevalence of skin malignant melanoma peaked age at 50 to 54 years old. The incidence peak age of males was older than that of females (55-59 years old for males vs. 50-54 years old for females), while the mortality peak age of males was younger than that of females (55-59 years old for males vs. 75-79 years old for females). With the increasing of SDI value, the incidence of skin malignant melanoma showed a linear growth trend. DALY rate was negatively correlated with SDI (P<0.05). ConclusionFrom 1990 to 2019, age-standardized incidence and prevalence of skin malignant melanoma in China are increasing, while DALY rate and mortality are decreasing, and these are correlated with social and medical development.
ObjectiveTo explore the effects and molecular mechanisms of histone methylase G9a inhibitor BIX-01294 on apoptosis in esophageal squamous cell carcinoma (ESCC).MethodsMTT assay and Colony-forming Units were adopted to determine the effects of BIX-01294 on the growth and proliferation of ESCC cell lines EC109 and KYSE150. Flow cytometry was used to analyze the apoptosis status of ESCC cells after the treatment of BIX-01294. The effects of BIX-01294 treatment on the expressions of G9a catalytic product H3K9me2, DNA double-strand break (DSB) markers, and apoptosis-related proteins were detected by Western blotting.ResultsBIX-01294 inhibited the growth of EC109 and KYSE150 cells in a dose-dependent manner (P<0.05), and BIX-01294 with the inhibitory concentration 50% (IC50) significantly inhibited the formation of colony (P<0.05). After 24 hours treatment of BIX-01294 (IC50), the apoptosis rate of EC109 cells increased from 11.5%±2.1% to 42.5%±5.4%, and KYSE150 cells from 7.5%±0.9% to 49.2%±5.2% (P<0.05). The expression level of the G9a catalytic product, H3K9me2, significantly decreased (P<0.05); while the expression of the DSB marker γH2AX was dramatically enhanced (P<0.05). We also found that the mitochondrial apoptosis pathway was activated and the expression levels of cleaved caspase3 and cleaved PARP were significantly elevated (P<0.05).ConclusionBIX-01294, the inhibitor of methyltransferase G9a, prompted apoptosis in ESCC cells by inducing DSB damage and activating mitochondrial apoptosis pathway.