Dr. Weeks’ Comment: Again, more data suggesting that vitamin C (ascorbate) is important for helping you or your loved ones fight cancer.
Ascorbate exerts anti-proliferative effects through cell cycle inhibition.
Cell cycle arrest is when growth/replication of cancer cells (or other cells) is stopped or interfered with.
Similar to apoptosis, cell cycle arrest requires the expression of genes that control the cell cycle.
The first stage, or “checkpoint” when a cell divides is moving from a phase called G0 to the next phase G1.
In this step the cell is making the key decision of whether the cell should divide, delay division, or enter a resting stage.
In cancer cells in this study, Vit C interferes with the G0/G1 transition.
Also in this study Vit C sensitized cancer cells to several common chemo drugs.
“Pre-treatment of tumor cells with ascorbate leads to increased cellular sensitivity towards Docetaxel, Epirubicin, Irinotecan and 5-FU.”
“For Docetaxel and 5-FU, a linear correlation between this sensitizing effect and the ascorbate dosage is observed.”
The killing effect by ascorbate was due to the extracellular production of hydrogen peroxide (H2O2). “We demonstrate higher therapeutic efficacy of ascorbate over DHAA in various cell lines… and identify the extracellular generation of H2O2 as critical mechanism of ascorbate action.”
FrÃ¶mberg A, Gutsch D, Schulze D, Vollbracht C, Weiss G, Czubayko F, Aigner A. Ascorbate exerts anti-proliferative effects through cell cycle inhibition and sensitizes tumor cells towards cytostatic drugs. Cancer Chemother Pharmacol. 2010 Aug 8. PubMed PMID: 20694726