Objective To explore the effect of calreticulin (CRT) on cell proliferation and invasion of human hepatocellular carcinoma cell line SMMC-7721 and HepG2.Methods SMMC-7721 and HepG2 cells were transfected with small interfering RNA (siRNA).The transfection rate was detected by immunoflurescence and western blot.The cell proliferation,invasion and apoptosis of SMMC-7721 and HepG2 cells were determined by using cell counting kit-8 (CCK-8) assays,transwell assays and flow cytometry,respectively.The p-Akt and Akt levels were detected by western blot.Results The growth inhibition rate in the siRNA experimental group of SMMC-7721 and HepG2 cells for 24,36 and 48 h were (41.0 ±2.2) ％,(46.5 ±1.6)％,(59.7 ±2.2)％ and (36.8 ±2.7)％,(47.3 ± 1.8)％,(61.5 ±3.2)％,respectively.The apoptosis rate after down-regulating the expression of CRT in SMMC-7721 and HepG2 cells for 36h were (45.2 ± 9.1) ％ and (48.9 ± 8.0) ％,respectively.Compared with the blank group and the negative control group,the growth inhibition rate in the siRNA experimental group was lower (P ＜0.05),but the apoptosis rate was significantly higher (P ＜ 0.05).Transwell experiments confirmed that the numbers of invaded SMMC-7721 and HepG2 cells in the blank group and the negative control group and siRNA experimental group were (96.8±7.3),(95.6±5.4),(34.0±4.2) and (124.0 ±9.9),(121.6 ±7.0),(70.4±9.5),respectively,indicating that cell invasion in the siRNA experimental group was significantly suppressed (P ＜ 0.05).The expression of p-Akt was decreased (P ＜ 0.05) after down-regulating the expression of CRT for 36h.Conclusion CRT gene silencing by siRNA can inhibit the SMMC-7721 and HepG2 cell proliferation and invasion,but increase the cell apoptosis by regulating PI3K/Akt signal pathway.

OBJECTIVES: To explore the development process of the postmortem interval (PMI) research in China from January 1990 to August 2020, research hotspots in different periods, authors and cooperation between institutions, and to provide a reference for the better development of PMI inference research through the visualization of the literature information of the PMI estimation research indexed in China National Knowledge Infrastructure (CNKI). METHODS: The information visualization analysis software CiteSpace 5.7.R1 was used to carry out big data analysis on hotspots, high-frequency keywords, authors, institutions and other information in the research literature on PMI inference from January 1990 to August 2020 indexed in CNKI. RESULTS: The peak time of publication of PMI was from 2006 to 2010 with 114 articles. In keyword co-occurrence network, the effective hot words were forensic entomology, DNA content analysis and some emerging words such as artificial intelligence and big data. In the cooperation network of institutions, the high-frequency institutions were mainly the scientific research institutions. The author cooperation network showed a trend of co-aggregation and multi-cooperation. CONCLUSIONS With the development of science and technology, the research on PMI estimation based on traditional methods is mature and novel strategies are emerging. Big data and artificial intelligence combined with forensic science provide new research directions on PMI estimation.
Artificial Intelligence ; Autopsy ; China ; Forensic Sciences ; Software