摘要：

Basal cell carcinomas in rats and squamous cell carcinomas in mice induced by a topical administration of a chemical carcinogen 3-methylcholanthrene (MCA) a single dose of 800 micrograms, were significantly reduced in number and size following a combined administration of vitamin C, a daily dose of 50 mg/kg b.wt. and MCA for 9 months. Ultrastructural studies of basal cancer cells and squamous cancer cells revealed an advanced cytolysis and disorganization of neoplastic cells, mitochondrial alterations, nuclear and nucleolar reduction, and increased phagolysosomes formation, following vitamin C and MCA administration compared to that of neoplastic cells following MCA alone. Scanning electron microscopic observations also revealed cytolysis, increased collagen synthesis, and cell disorganization with membrane disruption following vitamin C and MCA administration, as compared to round basal neoplastic or polyhedral squamous neoplastic cells following MCA treatment alone. These findings demonstrate that vitamin C exerts its antineoplastic effects by increasing cytolytic and autophagic activity, cell membrane disruption, and increased collagen synthesis, and thus, inhibits cancer cell metabolism and proliferation.

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