Study on the mechanism of circMTO1 regulating Wnt/β-catenin to inhibit proliferation and metastasis of breast cancer cell

doi:10.11958/20220183

Abstract

Abstract:

Objective To study the effect of a circRNA derived from MTO1 gene (circMTO1) on the proliferation and metastasis of breast cancer and its possible mechanism. Methods A total of 102 patients with invasive breast cancer were included in this study. Breast cancer cell lines MDA-MB-231, HCC-70, MCF-7 and human normal breast cell line MCF-10A were selected, and fluorescence quantitative PCR (qPCR) was used to detect the expression level of circMTO1 in breast cancer tissues and cell lines. The circMTO1 overexpression and circMTO1 knockdown plasmids were respectively constructed to transfect breast cancer cell lines, and which were divided into the NC group, the oe-circMTO1 group and the sh-circMTO1 group. The transfection effect was tested by qPCR. The MTS experiment was used to detect the cell proliferation ability of each group, and the Transwell experiment was used to detect the cell metastasis ability of each group. TOP/FOP luciferase assay was used to detect the activity of Wnt/β-catenin signaling pathway in each group of cells, and Western blotting was used to detect the expression of key proteins Wnt3a,β-catenin, cMyc, Cyclin D1 and matrix metalloproteinase 7 (MMP7) in Wnt/β-catenin signaling pathway. Results Compared with adjacent tissues and human normal breast cell lines, the relative expression of circMTO1 was significantly decreased in breast cancer tissues and breast cancer cell lines (P<0.05). The relative expression level of circMTO1 was lower in breast cancer patients with lymph node metastasis and TNM stage Ⅲ (P<0.05). Compared with the NC group, the relative expression of circMTO1 was significantly increased in the oe-circMTO1 group, the cell proliferation and metastasis ability and the activity of the Wnt/β-catenin signaling pathway were weakened, and the protein expressions of Wnt3a, β-catenin, cMyc, Cyclin D1 and MMP7 were also decreased (P<0.05). In the sh-circMTO1 group, the relative expression of circMTO1 was decreased, the proliferation and metastasis ability of cells and the activity of Wnt/β-catenin signaling pathway were enhanced, and the protein expression levels of Wnt3a, β-catenin, cMyc, Cyclin D1 and MMP7 were increased (P<0.05). Conclusion circMTO1 is down-expressed in breast cancer cells. circMTO1 inhibits the proliferation and metastasis of breast cancer cells by inhibiting Wnt/β-catenin.

Key words: breast neoplasms, gene expression regulation, neoplastic, cell proliferation, neoplasm metastasis, circMTO1, Wnt/β-catenin

CLC Number:

R737.9

Figures/Tables 6

References 16

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临床参数	n	circMTO1相对表达量	t
年龄（岁）
≤60	72	0.89±0.33	1.051
>60	30	0.82±0.24	1.051
肿瘤大小（cm）
≤2	43	0.93±0.34	1.172
>2	59	0.83±0.24	1.172
组织分级
Ⅰ-Ⅱ	38	0.91±032	1.012
Ⅲ	64	0.85±0.27	1.012
淋巴结转移
有	58	0.78±0.26	3.478^＊＊
无	44	0.99±0.35	3.478^＊＊
TNM分期
Ⅰ-Ⅱ	42	1.00±0.34	3.767^＊＊
Ⅲ	60	0.78±0.25	3.767^＊＊
ER
阳性	32	0.84±0.26	0.650
阴性	70	0.88±0.30	0.650
PR
阳性	35	0.81±0.26	1.468
阴性	67	0.90±0.31	1.468
HER-2
阳性	61	0.84±0.27	1.382
阴性	41	0.92±0.31	1.382

临床参数	n	circMTO1相对表达量	t
年龄（岁）
≤60	72	0.89±0.33	1.051
>60	30	0.82±0.24	1.051
肿瘤大小（cm）
≤2	43	0.93±0.34	1.172
>2	59	0.83±0.24	1.172
组织分级
Ⅰ-Ⅱ	38	0.91±032	1.012
Ⅲ	64	0.85±0.27	1.012
淋巴结转移
有	58	0.78±0.26	3.478^＊＊
无	44	0.99±0.35	3.478^＊＊
TNM分期
Ⅰ-Ⅱ	42	1.00±0.34	3.767^＊＊
Ⅲ	60	0.78±0.25	3.767^＊＊
ER
阳性	32	0.84±0.26	0.650
阴性	70	0.88±0.30	0.650
PR
阳性	35	0.81±0.26	1.468
阴性	67	0.90±0.31	1.468
HER-2
阳性	61	0.84±0.27	1.382
阴性	41	0.92±0.31	1.382

组别	n	circMTO1 相对表达水平	穿膜细胞数（个/视野）	TOP/FOP荧光素酶活性
NC组	3	1.01±0.02	69.33±6.81	0.97±0.03
oe-circMTO1组	3	3.57±0.55^a	32.67±4.25^a	0.49±0.03^a
sh-circMTO1组	3	0.41±0.11^ab	98.33±5.34^ab	1.69±0.12^ab
F		80.472^＊＊	104.829^＊＊	202.667^＊＊

组别	n	circMTO1 相对表达水平	穿膜细胞数（个/视野）	TOP/FOP荧光素酶活性
NC组	3	1.01±0.02	69.33±6.81	0.97±0.03
oe-circMTO1组	3	3.57±0.55^a	32.67±4.25^a	0.49±0.03^a
sh-circMTO1组	3	0.41±0.11^ab	98.33±5.34^ab	1.69±0.12^ab
F		80.472^＊＊	104.829^＊＊	202.667^＊＊

组别	cMyc		Cyclin D1		MMP7
NC组	0.52±0.02		0.64±0.05		0.45±0.06
oe-circMTO1组	0.17±0.02^a		0.28±0.02^a		0.33±0.03^a
sh-circMTO1组	1.47±0.20^ab		1.89±0.11^ab		1.97±0.18^ab
F	99.816^＊＊		428.420^＊＊		203.837^＊＊
组别		Wnt3a		β-catenin
NC组		0.42±0.04		0.48±0.05
oe-circMTO1组		0.15±0.02^a		0.19±0.03^a
sh-circMTO1组		1.02±0.09^ab		1.56±0.18^ab
F		176.703^＊＊		131.036^＊＊