Background: Redox dysregulation originating from metabolic alterations in cancer cells
contributes to their proliferation, invasion, and resistance to therapy. Conversely, these features represent
a specific vulnerability of malignant cells that can be selectively targeted by redox chemotherapeutics.
Amongst them, Vitamin K (VitK) carries the potential against cancer stem cells, in
addition to the rest of tumor mass.
Objectives: To assess the possible benefits and safety of VitK for cancer treatment using a systematic
review and meta-analysis with a mixed-methods approach.
Methods: We performed a systematic search on several electronic databases for studies comparing
VitK treatment with and without combination to the control groups. For quantitative studies, fully
or partially reported clinical outcomes such as recurrence rates, survival, overall response and adverse
reactions were assessed. For qualitative studies, a narrative synthesis was accomplished.
Results: Our analysis suggested that the clinical outcome of efficacy, the pooled hazard ratio for
progression-free survival, and the pooled relative risk for overall survival, and overall response
were significantly higher in the VitK therapy group compared to the placebo group (p<0.05). We
did not observe any significant difference in the occurrence of adverse events between groups.
Among qualitative studies, VitK treatment targeting myelodysplastic syndrome and advanced solid
tumors resulted in 24.1% and 10% of clinical response, respectively.
Conclusion: VitK not only exerts antitumor effects against a wide range of tumor types, but it also
has excellent synergism with other therapeutic agents.