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Published on: August 23, 2024
Effect of Photodynamic Therapy on the microRNA Level in Breast Cancer Tissues of Female Wistar Rats
O V Kazakov1, A V Kabakov2, A F Poveshchenko2
1Research Institute of Clinical and Experimental Lymphology - Affiliated Branch of Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia. kazakoff_oleg@mail.ru.
Abstract:
The expression of microRNA (miR-21, miR-221, miR-27a, and miR-429) was studied normal and tumor breast tissues of female Wistar rats before and after photodynamic therapy. In breast cancer, the levels of oncogenic microRNA (miR-21, miR-221, and miR-27a) were increased, while the level of tumor-suppressing miR-429 was reduced in comparison with the intact group. After photodynamic therapy, suppression of the expression levels of oncogenic microRNAs (miR-21, miR-221, and miR-27a) was noted. The level of tumor-suppressing miR-429 in breast tumor tissues remained reduced, as in the untreated breast cancer group.
Insights
Photodynamic therapy reduced oncogenic microRNAs (miR-21, miR-221, miR-27a) in rat breast tumors. However, tumor-suppressing miR-429 levels remained low after treatment, indicating potential for further therapeutic development.
Area of Science:
- Biomedical Sciences
- Molecular Biology
- Oncology
Background:
- MicroRNAs play crucial roles in gene regulation and are implicated in various cancers, including breast cancer.
- Specific microRNAs like miR-21, miR-221, miR-27a, and miR-429 have been associated with tumor development and suppression.
- Photodynamic therapy (PDT) is a treatment modality that uses light and a photosensitizer to destroy cancer cells.
Purpose of the Study:
- To investigate the expression profiles of key microRNAs (miR-21, miR-221, miR-27a, miR-429) in normal and breast tumor tissues of Wistar rats.
- To evaluate the impact of photodynamic therapy on the expression levels of these microRNAs in a rat breast cancer model.
Main Methods:
- Quantitative real-time PCR was used to measure microRNA expression levels.
- Breast tissue samples were collected from normal rats, untreated tumor-bearing rats, and rats that underwent photodynamic therapy.
- Comparative analysis of microRNA expression was performed across different experimental groups.
Main Results:
- In breast tumor tissues, oncogenic microRNAs (miR-21, miR-221, miR-27a) showed significantly increased expression, while tumor-suppressing miR-429 was downregulated compared to normal tissues.
- Following photodynamic therapy, a notable suppression in the expression of oncogenic microRNAs (miR-21, miR-221, miR-27a) was observed.
- The expression level of tumor-suppressing miR-429 in treated breast tumor tissues remained low, similar to the untreated tumor group.
Conclusions:
- Photodynamic therapy effectively downregulates oncogenic microRNAs involved in breast cancer progression.
- The persistent low expression of tumor-suppressing miR-429 after PDT suggests it may not be a direct target or biomarker for PDT efficacy in this model.
- Further research is warranted to explore the role of miR-429 and potential combination therapies to restore its tumor-suppressive function.
