Effects of Pharmacological Dose of Vitamin C on MDA-MB-231 Cells

Background/Objectives: In 2022, approximately 2.3 million women were diagnosed with breast cancer worldwide, resulting in 670,000 deaths, which accounted for 6.9% of all cancer-related deaths. In the United States, 1 in 8 women will be diagnosed with breast cancer during their lifetime. It was estimated that 2024 would identify about 310,720 women and 2800 men diagnosed with invasive breast cancer. The future global burden of breast cancer is projected to rise to over 3 million new cases and 1 million deaths by 2040. Approximately 20% of breast cancer diagnoses are triple-negative breast cancer (TNBC), a type of cancer that lacks receptors for estrogen (ER-negative), progesterone (PR-negative), and human epidermal growth factor receptor 2 (HER2/neu-negative). Consequently, TNBC does not respond to hormonal or targeted therapies, making it challenging to treat due to its rapid growth, metastasis, and high recurrence rate within the first three years of therapy. Alternative chemotherapies are needed to address this problem. A pharmacological dose of vitamin C (high-dose VC) has been identified as a potential treatment for some cancer cells. The present study aimed to evaluate whether VC has a therapeutic effect on TNBC, using MDA-MB-231 cells as the model. Additionally, VC's effects were trialed on other cancer cells such as MCF7 and on non-cancerous kidney HEK 293 and lung CCL205 cells. Methods: The MTT assay, Hoechst 33342 staining, nuclear-ID red/green staining, Rhodamine 123 staining, and Western blot analysis were employed to test the hypothesis that a pharmacological dose of VC can kill TNBC cells. Results: The upregulation of Apaf-1 and caspases -7, -8, and -9, the inhibition of matrix metalloproteinases (MMP-2 and MMP-9), a reduction in cell cycle protein expression, and the enhancement of tumor suppressor proteins such as p53 and p21 indicate that a pharmacological dose of VC has promising anti-cancer properties in the treatment of breast cancers. Conclusions: Pharmacological dose of VC exerts significant anti-cancer effects in MDA-MB-231 cells by promoting apoptosis, inhibiting metastasis, disrupting cell cycle progression, and enhancing tumor suppressor activity.