ABSTRACT
Objective:
To explore the inhibitory mechanism of herb cake-partitioned
moxibustion on
tumor growth in
colitis-associated colorectal cancer(CAC)based on
histone lysine demethylase 4D(KDM4D).
Methods:
Inbred
male Sprague-Dawley rats were randomly divided into a normal group,a CAC group,a herb cake-partitioned
moxibustion group,and an inhibitor group.Except the normal group,
rats in the other three groups were treated with
azoxymethane(AOM)combined with
dextran sulfate sodium(DSS)to make CAC
rat models.
Rats in the normal group and the CAC group did not receive interventions;
rats in the herb cake-partitioned
moxibustion group received
moxibustion at Qihai(CV6)and bilateral Tianshu(ST25),2 cones for one point each
time,once a day for 30 d with 1-day
rest every week;
rats in the inhibitor group received
intraperitoneal injection of KDM4D inhibitor,5-chloro-
8-hydroxyquinoline(5-c-8HQ),once a day for 30 d.After intervention,the general condition,
colon length,
tumor number and volume,and histopathological
colon changes were observed.The expression of
adenomatous polyposis coli(APC),axis inhibitor(Axin),
cyclin D1,
matrix metalloproteinase(
MMP)-7 and
MMP-9 mRNAs were detected by real-
time quantitative
polymerase chain reaction.The
proliferating cell nuclear antigen(
PCNA),cleaved caspase3,KDM4D,APC,and
Axin proteins were detected by
immunohistochemistry.
Results:
Compared with the normal group,the general condition was poor,the
colon length was significantly shortened(P<0.01),the number and volume of colonic
tumors were increased(P<0.01),the structure of glandular duct was obviously disordered with"
back-to-
back"and cowall phenomenon,and also high-grade
adenocarcinoma formed;the
protein expression levels of
PCNA and KDM4D were significantly increased(P<0.01),while cleaved caspase3,APC,and Axin were significantly reduced(P<0.01);the
mRNA expression levels of
cyclin D1,
MMP-7,and
MMP-9 were significantly increased(P<0.01),while APC and Axin were significantly reduced(P<0.01)in the CAC group.Compared with the CAC group,the general condition was improved,the length of
colon was significantly increased(P<0.01),the number and volume of the colonic
tumors were reduced(P<0.05),and the
colon tissues showed
epithelial cell proliferation with enlarged and deep
staining nuclei,dysplasia and inflammatory
cell infiltration;the
protein expression levels of
PCNA and KDM4D were significantly reduced(P<0.01),while the cleaved caspase3,APC,and Axin were significantly increased(P<0.01);the
mRNA expression levels of
cyclin D1,
MMP-7,and
MMP-9 were reduced(P<0.05),while the APC and Axin were increased(P<0.05)in the
colon tissues of
rats in the herb cake-partitioned
moxibustion group and the inhibitor group.
Conclusion:
Herb cake-partitioned
moxibustion regulated abnormally expressed KDM4D in CAC
rats,activated APC and Axin,the
upstream molecules of Wnt/β-
catenin pathway,inhibited abnormally activated
downstream molecules of Wnt/β-
catenin pathway.This may be a key mechanism of herb cake-partitioned
moxibustion in inhibiting CAC
tumor growth.