The Use of Ascorbic Acid in the Treatment of Cancer

Di Liang^*
*Correspondence: Di Liang, Department of Tumor Diagnosis and Therapy, Guangxi Medical University, Nanning, China, Email:

Keywords

Ascorbic acid • Immune system • Cancer treatment

Introduction

The idea that vitamin C could play a role in cancer treatment dates back to the 1970s, primarily through the work of Linus Pauling, a Nobel Prize-winning chemist, and Ewan Cameron, a Scottish surgeon. Pauling and Cameron conducted preliminary studies suggesting that high doses of vitamin C could improve the survival times of cancer patients. Their findings generated significant excitement but were met with skepticism within the medical community due to methodological flaws and the inability to replicate results in subsequent studies. Ascorbic acid is a potent antioxidant, capable of scavenging reactive oxygen species (ROS) and protecting cells from oxidative damage. In cancer therapy, this property is paradoxical because while antioxidants generally protect cells, high concentrations of ascorbic acid can produce hydrogen peroxide in the presence of catalytic metal ions, which can selectively kill cancer cells. At pharmacological doses, ascorbic acid can act as a pro-oxidant in the extracellular space, generating hydrogen peroxide and other ROS that selectively damage cancer cells due to their lower catalase activity compared to normal cells [1].

In collagen synthesis, ascorbic acid is essential for the synthesis of collagen, a major component of the extracellular matrix. By promoting collagen production, vitamin C may inhibit the metastasis of cancer cells by reinforcing the structural integrity of tissues. Vitamin C is known to modulate the immune system. It can enhance the function of various immune cells, including T-cells and natural killer cells, potentially aiding the body’s immune response against cancer. Ascorbic acid can influence gene expression by acting as a cofactor for enzymes involved in the demethylation of DNA and histones. This epigenetic regulation can lead to the reactivation of tumor suppressor genes [2].

Literature Review

The clinical evidence for the use of ascorbic acid in cancer treatment has been mixed. Early studies by Pauling and Cameron reported improved survival times in cancer patients treated with high doses of vitamin C. However, later randomized controlled trials conducted by the Mayo Clinic failed to replicate these findings, leading to a decline in interest. In recent years, there has been a resurgence of interest in high-dose vitamin C as an adjunct to conventional cancer therapies. Advances in understanding its pharmacokinetics have led to new clinical trials investigating its efficacy and safety. Oral administration of vitamin C results in limited plasma concentrations due to tight regulation by the kidneys. However, intravenous (IV) administration can achieve significantly higher plasma concentrations, which are necessary for the proposed therapeutic effects [3]. Several clinical trials have explored the use of IV vitamin C in combination with standard chemotherapy and radiation therapy. These studies suggest that high-dose vitamin C can enhance the efficacy of conventional treatments while reducing their toxicity. For instance, a phase I/II clinical trial at the University of Iowa found that IV vitamin C, when combined with standard chemotherapy, improved outcomes in patients with pancreatic cancer. Recent trials have also provided insights into the mechanisms by which high-dose vitamin C may exert its effects. Studies have demonstrated that vitamin C can induce oxidative stress selectively in cancer cells, leading to cell death while sparing normal cells. Additionally, vitamin C has been shown to enhance the cytotoxic effects of certain chemotherapy drugs.The current status of ascorbic acid in cancer treatment is one of cautious optimism. While early clinical trials have shown promising results, larger and more rigorous studies are needed to confirm these findings and establish standardized treatment protocols.

Discussion

Understanding the genetic and metabolic profiles of patients may help identify those who are most likely to benefit from high-dose vitamin C therapy. Biomarkers could be developed to predict response to treatment. Determining the optimal dosing regimen for IV vitamin C is critical. This includes identifying the appropriate dosage, frequency, and duration of treatment to maximize efficacy and minimize side effects [4,5]. Further research is needed to explore the synergistic effects of vitamin C with other cancer treatments. This includes investigating its role in enhancing the effectiveness of chemotherapy, radiation therapy, and emerging therapies such as immunotherapy.Continued research into the molecular mechanisms by which vitamin C exerts its anti-cancer effects will provide a better understanding of its potential therapeutic benefits. This includes studying its impact on oxidative stress, immune modulation, and epigenetic regulation.Large-scale, randomized controlled trials are essential to establish the efficacy and safety of high-dose vitamin C in cancer treatment. These trials should include diverse patient populations and various types of cancer to determine the generalizability of the results. The use of ascorbic acid in the treatment of cancer is a promising but still controversial area of research. While early studies suggested potential benefits, subsequent trials produced mixed results [6]. Recent advances in our understanding of vitamin C’s pharmacokinetics and mechanisms of action have reignited interest in its therapeutic potential. High-dose IV vitamin C has shown promise as an adjunct to conventional cancer therapies, with the potential to enhance efficacy and reduce toxicity.

Conclusion

The need for rigorous clinical trials, optimization of dosing regimens, and a deeper understanding of the underlying mechanisms. As research continues, vitamin C may become an important tool in the fight against cancer, offering new hope to patients and clinicians alike. Until then, its use should be guided by the best available evidence, and patients should be informed of both the potential benefits and limitations of this treatment approach.

Acknowledgement

None.

Conflict of Interest

None.

References

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