Effects of normal mitochondrial transplantation on proliferation, apoptosis and stemness of triple-negative breast cancer cells
10.3760/cma.j.cn112152-20231222-00381
- VernacularTitle:正常线粒体移植对三阴性乳腺癌细胞增殖凋亡及干性的影响
- Author:
Liangliang MA
1
;
Ke ZHANG
;
Jiangning LU
;
Lixin SUN
;
Long YU
;
Yuliang RAN
;
Lichao SUN
Author Information
1. 国家癌症中心 国家肿瘤临床医学研究中心 中国医学科学院北京协和医学院肿瘤医院分子肿瘤学国家重点实验室，北京 100021
- Keywords:
Breast neoplasms;
Triple-negative breast cancer;
Mitochondrial transplantation;
Cell proliferation;
Cell apoptosis;
Cell stemness
- From:
Chinese Journal of Oncology
2024;46(9):878-888
- CountryChina
- Language:Chinese
-
Abstract:
Objectives:To observe the mitochondrial morphology of normal and triple-negative breast cancer cells, extract mitochondria from normal cells, and investigate the effects of mitochondrial transplantation on proliferation, apoptosis, and stemness of triple-negative breast cancer cells.Methods:The morphology of mitochondria was observed by transmission electron microscope. Mitochondria were extracted by mitochondrial extraction kit, mitochondrial protein was identified by western blot, and mitochondrial activity was detected by mitochondrial membrane potential detection kit. MitoTracker Green or MitoTracker Deep Red fluorescent probes were used to label the mitochondria of living cells, and the degree of mitochondria entering LTT cells was observed by confocal laser microscopy at 12, 24, and 96 hours. The effects of mitochondrial transplantation on proliferation, apoptosis, and stemness of breast cancer cells were examined by CCK8, colony formation assay, flow cytometry, and sphere formation assay after 24 hours of mitochondrial transplantation.Results:The mitochondria of normal cells were rod-shaped or elongated, while the mitochondria of triple-negative breast cancer cells were swollen and vacuolated. Western blot results showed that cytochrome c oxidase subunit I (MT-CO1) protein encoded by mitochondria was present in the isolated mitochondria. The content of heat shock protein 60 (HSP60) was higher in mitochondria than that in cytoplasm. The result of the multi-mode microplate reader showed that the content of mitochondrial J-aggregates/monomer was 1.67±0.06, which was significantly higher than 0.35±0.04 of the control group ( P＜0.001). Exogenous mitochondria were observed in LTT cells at 12, 24, and 96 hours after mitochondrial transplantation. The results of the CCK8 experiment showed that OD450 of LTT cells was 0.27±0.13 after 48 hours transplantation, which was lower than 0.62±0.36 of the control group ( P=0.023). The OD450 of MDA-MB-468 cells was 0.30±0.03, which was lower than 0.65±0.10 of the control group ( P=0.004). After 120 hours of mitochondrial transplantation, OD450 in both groups was still significantly lower than that in the control group (P＜0.01). The number of clones formed by mitochondrial transplantation of LTT cells was 21.33±7.31, which was lower than 35.22±13.59 of the control group ( P=0.016). Flow cytometry showed that the early apoptosis rate of LTT cells was (30.07±2.15)% after 24 hours of mitochondrial transplantation, which was higher than 2.07±1.58 of the control group ( P＜0.001). The proportion of early apoptosis in MDA-MB-468 cells was 24.47%±5.22%, which was higher than (7.83±2.06)% in the control group ( P=0.007). In addition, the number of mitochondria transplanted LTT cells into the cell sphere was 46.25±5.40, which was significantly lower than 62.58±6.43 of the control group ( P＜0.001). Conclusion:Normal mitochondria can enter triple-negative breast cancer cells by co-culture, inhibit the proliferation and stemness of triple-negative breast cancer cells, and promote the apoptosis of triple-negative breast cancer cells.
