ABSTRACT
Objective To study the effect of radiofrequency ablation (RFA) with sublethal temperature on the production of liver cancer stem cells (LCSCs) and on the expression of LCSCs-related transcriptional factors.Methods Mouse hepl-6 hepatoma cell line and clinical samples of patients with hepatocellular carcinoma (HCC) were used to test the expressions of LCSCs-related markers and transcriptional factors.Results Different temperatures were used to stimulate Hep1-6 cells,and it was proved that the temperature of 45℃ was a sublethal temperature that could not induce cell death.Flow cytometry testing showed that treatment with 45℃ could obviously increase CD13+,CD44+,CD90 and CD133+ Hep1-6 cells,suggesting that treatment with 45℃ could increase the production of above mentioned types of LCSCs in hep1-6 cells.Real-time quantitative polymerase chain reaction (RT-qPCR) assay indicated that the temperature of 45℃could cause significant increase in CD13,CD90 and CD133 mRNA.In all 5 HCC patients,CD13 mRNA in the recurrent HCC lesions was remarkably increased,CD133 mRNA was increased in 4 patients with recurrent HCC,and CD90 mRNA was increased in only one patient with recurrent HCC.Flow cytometry testing revealed that CD13+ LCSCs were strikingly increased in 4 recurrent HCC patients,while CD133+LCSC was increased in only one patient,suggesting that more close correlation existed between the increase of CD13+ LCSCs and the temperature of 45℃.RT-qPCR assay showed that in 4 recurrent HCC patients with increased CD13+ LCSC,the Sox2 and Stat2 among 13 LCSCs-related transcriptional factors were obviously increased.Flow cytometry testing showed that 45℃ treatment also increased the expression of Sox2 and Stat1 mRNA in Hep1-6 cells.Finally,Sox2 and Stat1 could be knockdown by siRNAs,indicating that both Sox2 and Stat1 transcriptional factors were involved in 45℃-induced production of CD13+ LCSCs in Hep1-6 cells.Conclusion In RFA therapy,the use of sublethal temperature of 45℃ can increase CD13+LCSCs,which is related to the promotion of Sox2 and Stat1 expression.The results of this study can be used for reference in the research of liver cancer recurrence.
ABSTRACT
In order to find microRNA associated with HBV infection and to explore the mechanism of the infection, first of all, we found in our preliminary study that in HepG2 cells transfected with HBV expression plasmid, miR-122 expression was up-regulated, suggesting that miR-122 was related to the HBV infection. On this basis, in the present study, miR-122 and pCH9-HBV1.1 plasmid were cotransfected into HepG2 cells. Southern blot detection result showed that miR-122 can inhibit HBV replication. Using MiRanda computer software, HBx was predicted to be the target sequence of miR-122; Luciferase reporter gene system and Western blot detection of HBx protein expression changes were further used to verify the HBx expression regulated by miR-122. And finally, it can be speculated that miR-122 may affected HBV replication by regulating the expression of HBx.