Ovário Terapêutica

High-Dose Parenteral Ascorbate Enhanced Chemosensitivity of Ovarian Cancer and Reduced Toxicity of Chemotherapy

Escrito por Carla Brito Lopes

Ascorbate (vitamin C) was an early, unorthodox therapy for cancer, with an outstanding safety profile and anecdotal clinical benefit. Because oral ascorbate was ineffective in two cancer clinical trials, ascorbate was abandoned by conventional oncology but continued to be used in complementary and alternative medicine. Recent studies provide rationale for reexamining ascorbate treatment.

Because of marked pharmacokinetic differences, intravenous, but not oral, ascorbate produces millimolar concentrations both in blood and in tissues, killing cancer cells without harming normal tissues. In the interstitial fluid surrounding tumor cells, millimolar concentrations of ascorbate exert local pro-oxidant effects by mediating hydrogen peroxide (H2O2) formation, which kills cancer cells.

We investigated downstream mechanisms of ascorbate-induced cell death. Data show that millimolar ascorbate, acting as a pro-oxidant, induced DNA damage and depleted cellular adenosine triphosphate (ATP), activated the ataxia telangiectasia mutated (ATM)/adenosine monophosphate–activated protein kinase (AMPK) pathway, and resulted in mammalian target of rapamycin (mTOR) inhibition and death in ovarian cancer cells.

The combination of parenteral ascorbate with the conventional chemotherapeutic agents carboplatin and paclitaxel synergistically inhibited ovarian cancer in mouse models and reduced chemotherapy-associated toxicity in patients with ovarian cancer. On the basis of its potential benefit and minimal toxicity, examination of intravenous ascorbate in combination with standard chemotherapy is justified in larger clinical trials.


Citation: [Y. Ma, J. Chapman, M. Levine, K. Polireddy, J. Drisko, Q. Chen, High-Dose Parenteral Ascorbate Enhanced Chemosensitivity of Ovarian Cancer and Reduced Toxicity of Chemotherapy. Sci. Transl. Med. 6, 222ra18 (2014)]. Reprinted with permission from AAAS.

Sobre o autor

Carla Brito Lopes

Carla nasceu a 14 de Fevereiro de 1977 em Viana do Castelo. Completou o bacharelato em Anatomia Patológica, Citológica e Tanatológica na ESTES-Porto em 1998 e licenciou-se em 2001 pela Escola Superior de Tecnologia da Saúde em Lisboa. Concluiu a certificação em Laboratory Management pela ASCP (American Association of Clinical Pathology) em Setembro de 2016.
Actualmente encontra-se a frequentar mestrado em Genética Molecular e Biomedicina na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa.