ObjectiveTo observe the effect of
betulinic acid(BetA) on the
growth of
human cytokine induced killer(CIK)
cells and the
killing activity of
CIK cells on the
gastric cancer cells in vitro before and after induced by
betulinic acid,explore its mechanism.MethodsPeripheral
blood mononuclear
cell (PBMC) were
separated form the healthy and were induced with various of
cytokine to become
CIK cells in vitro.
CIK cells were collected on the tenth day and were induced with
betulinic acid in different concentrations,followed by 48 h,the colorimetric methyl thiazolyl tetrazolium(MTT)
method assay the proliferation rate of
human CIK cells.
Flow cytometry (FCM) was used to detect the expression changes of
perforin,
granzyme B and CD107a of
human CIK cells before and after
betulinic acid-induced.
Lactate dehydrogenase (LDH) release assay was used to
measure the influence on cytotoxic activity of
CIK cells induced by
betulinic acid against
gastric cancer cell line SGC-7901
in vitro.
Western blot assay was used to
measure the extracellular signal-regulated kinase1/2 (ERK1/2),and adapter
proteins SH2-domain containing
leukocyte protein of 76KD(SLP-76) and linker for activative of
T cells(LAT) expression changes of
human CIK cells before and after
drug-induced.ResultsBetulinic
acid can promote
CIK cells growth when the concentration were in 0.08-10 μg/ml,the expression of
perforin,
granzyme B and CD107a of
CIK cells were significantly higher than
control group(P<0.05) when the concentration of
betulinic acid were in 0.3 μg/ml.In the meanwhile,the cytotoxic activity of
CIK cells in vitro against
gastric cancer cell line SGC-7901 were also remarkably higher than the
control group (P<0.05).The expression of SLP-76,LAT and ERK1/2 were significantly increased to a certain extent than the
control group( P<0.05 ),when
CIK cells were treated with
betulinic acid.ConclusionThese results suggest that
betulinic acid can promote
CIK cells growth in some concentrations and increase the cytotoxic activity of
CIK cells against
gastric cancer cell line SGC-7901,its mechanism may related with two factors,on the one
hand,enhancing the activity of SLP-76,LAT and ERK1/2,on the other
hand,increasing the expression of
perforin,
granzyme B and CD107a on the surface of
CIK cells.