Dysregulation of the miR-21/PTEN/Akt Axis and Its Association with Ki-67 Proliferation in Breast Cancer

Authors

DOI:

https://doi.org/10.55544/sjmars.5.3.7

Keywords:

breast cancer, miR-21, PTEN, Akt, p-Akt, Ki-67, qRT-PCR, Immunohistochemistry

Abstract

Breast cancer is a common cancer in women. miR-21 is an oncogenic microRNA which can downregulate PTEN. PTEN loss may lead to increased Akt signaling and proliferation. Ki-67 is a marker of proliferation. This may contribute to the aggressiveness of breast cancer. This paper examined the expression of miR-21 and its correlation with PTEN, Akt activation and Ki-67 in breast cancer tissues in Baghdad, Iraq. A case – control study carried out on Iraqi female patients. The sample size was 120 women (28-75 years). The 60 cases were diagnosed with breast cancer and the 60 controls with non-tumor tissue. The results were collected from Medical City, Baghdad, Iraq, between 12 May 2024 and 9 September 2025. The expression of miR-21 and PTEN mRNA was assessed by qRT-PCR. PTEN and Ki-67 were measured by IHC. Total Akt and p-Akt were measured by ELISA and western blot. Descriptive statistics, Welch t-test, Mann-Whitney test, correlation, effect size, categorical summaries and ROC analysis were used. Tumor samples had increased miR-21, total Akt, p-Akt and Ki-67. They had lower PTEN mRNA, and lower PTEN IHC scores. The greatest differences were for miR-21, p-Akt and Ki-67, with p values of less than 0.001. Conclusion: The results suggest a role for miR-21/PTEN/Akt/Ki-67 pathway in breast cancer. It may be used in regional biomarker testing with conventional histology.

References

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Published

2026-06-30

How to Cite

Sabri, I. A. (2026). Dysregulation of the miR-21/PTEN/Akt Axis and Its Association with Ki-67 Proliferation in Breast Cancer. Stallion Journal for Multidisciplinary Associated Research Studies, 5(3), 47–53. https://doi.org/10.55544/sjmars.5.3.7

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Vol. 5 No. 3 (2026): June Issue

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