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Let-7a mimic attenuates CCL18 induced breast cancer cell metastasis through Lin 28 pathway
Lei Wang1, Yu-Xia Wang2, De-Zhong Zhang1
1Department of General Surgery, The First Affiliated Hospital of Xinxiang Medical University, 453100, Xinxiang, PR China.
Background:
MicroRNAs are believed to influence breast cancer cell tumorgenicity by interacting with the production of tumor associated macrophages. At this stage, this hypothesis lacks sufficient empirical evidence. Our study is an investigation of the effects of let-7a on the function of human breast cancer cell lines that had undergone chemokine ligand 18 (CCL18) stimulation.
Methods:
Two breast cancer cell lines MDA-MB-231 and MCF-7 were transfected with let-7a mimics with or without CCL18 simulation. The expression level of let-7a was evaluated with qRT-PCR. Our study examined cell proliferation, migration and cell cycles following let-7a treatment. The predicted target of let-7a was identified and confirmed in vitro by a dual luciferase reporter system. The associations between let-7a, CCL18 and target gene expression were evaluated using RT-PCR and the Western blotting method.
Results:
The downregulated expression level of let-7a was observed in both breast cancer cell lines. When compared to the control and CCL18 stimulation groups, cell proliferation and migration in MDA-MB-231 and MCF-7 cells were significantly inhibited by let-7a. Furthermore, the cell cycle was dramatically blocked at the G2/M phase. The luciferase reporter identified Lin28 as the direct binding target of let-7a in both breast cancer cell lines.
Conclusion:
Upregulation of let-7a carries the potential to reverse CCL18 induced cell proliferation and migration alteration in breast cancer cells by regulating Lin28 expression. Our results provided evidence which suggests the use of let-7a as a therapeutic agent in the treatment of breast cancer.
Insights
MicroRNA let-7a inhibits breast cancer cell proliferation and migration by targeting Lin28. Upregulating let-7a may reverse chemokine ligand 18 (CCL18) effects, offering therapeutic potential for breast cancer treatment.
Area of Science:
- Molecular Biology
- Oncology
- Biochemistry
Background:
- MicroRNAs (miRNAs) are implicated in regulating tumor-associated macrophages and breast cancer cell tumorigenicity.
- The specific role of let-7a in breast cancer, particularly in response to chemokine ligand 18 (CCL18) stimulation, requires further empirical investigation.
- This study explores the functional impact of let-7a on human breast cancer cell lines under CCL18 stimulation.
Purpose of the Study:
- To investigate the effects of let-7a on the proliferation, migration, and cell cycle of human breast cancer cell lines (MDA-MB-231 and MCF-7).
- To identify and validate the direct target of let-7a in these cell lines.
- To elucidate the regulatory relationship between let-7a, CCL18, and target gene expression in breast cancer.
Main Methods:
- Transfection of MDA-MB-231 and MCF-7 cells with let-7a mimics, with or without CCL18 stimulation.
- Quantification of let-7a expression using quantitative real-time PCR (qRT-PCR).
- Assessment of cell proliferation, migration, and cell cycle progression.
- Identification and in vitro confirmation of let-7a's direct target using a dual-luciferase reporter system.
- Evaluation of gene expression using RT-PCR and Western blotting.
Main Results:
- Downregulated let-7a expression was observed in both breast cancer cell lines.
- let-7a significantly inhibited cell proliferation and migration in MDA-MB-231 and MCF-7 cells compared to controls and CCL18-stimulated groups.
- let-7a treatment led to cell cycle arrest at the G2/M phase.
- Lin28 was identified as the direct binding target of let-7a in both cell lines.
Conclusions:
- Upregulation of let-7a can potentially reverse CCL18-induced alterations in breast cancer cell proliferation and migration by regulating Lin28 expression.
- These findings provide evidence supporting the potential use of let-7a as a therapeutic agent for breast cancer treatment.
- let-7a acts as a tumor suppressor in breast cancer by targeting Lin28 and affecting cell cycle progression.
