Objective: To observe the inhibitory effect of astragalus
polysaccharides (APS) on
growth of
human breast cancer MDA-MB-231
xenograft tumor in
nude mice and its effect on the
apoptosis of
tumor cells , in order to study the effect of APS on
growth and induction of
apoptosis of
triple negative breast cancer MDA-MB-231 and its possible molecular mechanism.
Method: Human breast cancer cell MDA-MB-231 was inoculated into the right axillary subcutaneous of BALB/c-nu
female nude mice to establish the transplanted
tumor model of
breast cancer . Eighteen
nude mice were randomly divided into 3 groupsmodel group (saline per day), low-
dose APS group (200 mg·kg-1 APS per day), and high-
dose APS group (400 mg·kg-1 APS per day), with 6
rats in each group. The
drug was administered by gavage (200 μL) daily for 21 days. In the experiment, the length and diameter of
breast cancer transplanted
tumor were measured every two days, and the
tumor volume was recorded and calculated. At the end of the experiment, the changes of
tumor mass and
tumor volume of the low and high-
dose APS groups and the model group were observed and compared, and the
tumor inhibition rate was calculated. The
cell morphology in
tumor tissue was observed by
hematoxylin -
eosin (HE)
staining , and Terminal-deoxynucleoitidyl
transferase mediated nick end labeling (
TUNEL ) was used to verify the
apoptosis of
breast cancer tissues . The expressions of
apoptosis -related
proteins , such as
B-cell lymphoma /
leukemia -2
protein (Bcl-2), Bcl-2 associated X
protein (Bax),
Caspase in
tumor tissues was detected by
Western blot .
Result: The
tumor volume of
breast cancer decreased in the low and high-
dose APS groups, and the
tumor inhibition rates were 37.9%and 57.57%, respectively, with statistically significant differences from the model group (PP0.01). HE of
tumor tissue cells showed that APS led to obvious morphological changes, with
apoptosis in the
tissue cells .
TUNEL staining showed that the
apoptosis rate of
tumor cells in APS intervention groups was higher than that in
control group .
Western blot showed that expression of Bcl-2
protein decreased(PPPP
Conclusion: APS can effectively inhibit the
growth of MDA-MB-231
breast cancer xenografts in
nude mice and induce
apoptosis in
human breast cancer MDA-MB-231 cells . The mechanism may be related to the effect of APS on expressions of
apoptosis -related
proteins Bcl-2, Bax,
Caspase-9 and
Caspase-7 in
breast cancer cells .