Effect and mechanism of ikkβ on proliferation, apoptosis, and metastasis of breast cancer cells with different expression levels of leptin and its receptors.

Abstract

e15592 Background: To investigate the effect and mechanism of IKKβ on proliferation, apoptosis, invasion and metastasis of breast cancer cells with different expression levels of leptin and ObR. Methods: IKKβ in breast cancer cells was knocked down via virus transfection technology. MTT, flow cytometry, cell scratch test and clone formation test were used to observe the effect of IKKβ on proliferation, apoptosis and metastasis of breast cancer cells with different expression levels of leptin and ObR. RT-PCR was used to detect the downstream genes expressions in IKKβ signaling pathway. Results: The expression levels of leptin and ObR in MDA-MB-231 cells were higher than those in MCF-7 cells. Lentivirus can successfully infect breast cancer cells in vitro and knock down the expression of IKKβ. Knocking down IKKβ reduced the viability of MDA-MB-231 cells, but had little effect on MCF-7, and had an effect on the cell cycle of both cells. After knocking down IKKβ, the apoptotic rate of MDA-MB-231 cells increased. There was no significant difference in the apoptotic rate of MCF-7 cells. The number of clones of MCF-7 and MDA-MB-231 cells decreased, and the difference was significant. The effect on MDA-MB-231 cells was more significant. The scratch mobility of MDA-MB-231 cells decreased significantly, with significant difference.After knocking down IKKβ, the expressions of leptin and ObR, IKBKG, P65 and HIF in MCF-7 cells were significantly decreased, and there was statistical significance. However, the above indicators were significantly increased in MDA-MB-231 cells. The expression level of IKBKG was increased significantly, whereas that of HIF did not differ significantly, as compared with that of control group. Conclusions: The proliferation, metastasis and apoptosis of MDA-MB-231 cells were inhibited after blocking the IKKβ pathway, while the proliferation of MCF-7 cells was inhibited, and the apoptosis did not change significantly. The difference between the two cells may be related to the different expression levels of leptin and ObR.After blocking the IKKβ signaling pathway, the expressions of genes related to the IKKβ signaling pathway in MDA-MB-231 cells were increased, whereas those in MCF-7 cells were decreased, which might be related to the different expression levels of leptin and ObR.After knocking down IKKβ, the expressions of HIF gene in MCF-7 cells were decreased, whereas those in MDA-MB-231 cell lines were not affected. It needs to be verified whether this difference is related to leptin and ObR.