JIANG Rui-yang,XU Chang-liang,CHENG Hai-bo,et al.Effect and Mechanism of Xianlian Jiedu Prescription Against Proliferation of Colorectal Cancer Cells in Hypoxic Microenvironment[J].Chinese Journal of Experimental Traditional Medical Formulae,2022,28(08):79-85.
JIANG Rui-yang,XU Chang-liang,CHENG Hai-bo,et al.Effect and Mechanism of Xianlian Jiedu Prescription Against Proliferation of Colorectal Cancer Cells in Hypoxic Microenvironment[J].Chinese Journal of Experimental Traditional Medical Formulae,2022,28(08):79-85. DOI: 10.13422/j.cnki.syfjx.20220422.
Effect and Mechanism of Xianlian Jiedu Prescription Against Proliferation of Colorectal Cancer Cells in Hypoxic Microenvironment
To study the effect of Xianlian Jiedu prescription (XLJDP) on the activation of nuclear transcription factor-
κ
B (NF-
κ
B) signaling pathway induced by bromodomain-containing protein 4 (Brd4) in hypoxic microenvironment and to explore its mechanism in inhibiting the proliferation of colorectal cancer HT-29 cells.
Method
2
The human colorectal cancer HT-29 cells were cultured in a hypoxic incubator or normoxia incubator and treated with XLJDP at 0.8,1,1.2,1.6,3.2,6.4,and 12.8 g·L
-1
for 48 h, respectively. Following the detection of cell vitality using methyl thiazolyl tetrazolium (MTT) colorimetry, the effects of XLJDP (1.25,2.5,and 5 g·L
-1
) on the cell mitochondrial membrane potential were determined using a fluorescent probe (JC-1), and the apoptosis of colorectal cancer HT-29 cells was detected by flow cytometry. The cell colony formation assay and 5-ethynyl-2'-deoxyuridine (EDU) staining were conducted to test the proliferation of colorectal cancer HT-29 cells. The Western blot was carried out to measure the expression levels of Brd4 and its downstream relevant proteins such as c-Myc and hexamethylene bisacetamide-inducible protein 1 (HEXIM1), as well as the effects of XLJDP on related proteins in the NF-
κ
B signaling pathway.
Result
2
Compared with the blank control group, XLJDP at 0.8,1,1.2,1.6,3.2,6.4,and 12.8 g·L
-1
inhibited the vitality of colorectal cancer HT-29 cells (
P<
0.05 ,
P<
0.01), with the median inhibitory concentration (IC
50
) under the hypoxic condition higher than that under the normoxia condition. Compared with the blank control group, XLJDP at 1.25,2.5,and 5 g·L
-1
significantly decreased the mitochondria membrane potential, enhanced the apoptosis (
P<
0.05,
P<
0.01), and lowered the number of cell colonies and also the EDU-positive cells (
P<
0.05,
P<
0.01). The results of Western blot showed that compared with the blank control group, XLJDP at 1.25,2.5,and 5 g·L
-1
down-regulated Brd4, c-Myc, p-NF-
κ
B p65, and p-I
κ
B
α
protein expression to varying degrees and up-regulated the expression of HEXIM1 (
P<
0.05,
P<
0.01).
Conclusion
2
In the hypoxic microenvironment, XLJDP inhibits the proliferation of colorectal cancer HT-29 cells regulated by Brd4, which may be related to its inhibition of the activation of NF-
κ
B signaling pathway.
关键词
Keywords
references
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