Ornithine Decarboxylase Overexpression Is a Sufficient Condition for Tumor Promotion in Mouse Skin

The study investigated the effect of dimethylarsinic acid (DMA) on skin carcinogenesis in K6/ODC transgenic mice, which are more sensitive to carcinogens. Female C57BL/6J K6/ODC transgenic mice were treated with DMA, TPA, or a control after initiation with DMBA. The results showed that DMA significantly accelerated the induction of skin tumors, similar to TPA, indicating that DMA promoted skin tumorigenesis in these transgenic mice.

In this study, researchers investigated whether overexpression of ornithine decarboxylase (ODC) was sufficient for tumor promotion in mouse skin. They used transgenic mice with high ODC expression in epidermal keratinocytes and found that these mice were more sensitive to carcinogen initiation compared to controls. Notably, mice with ODC overexpression in hair follicle keratinocytes developed tumors without the need for additional tumor promoters. The study concluded that ODC overexpression was sufficient to activate target cells in hair follicles, leading to clonal expansion and epidermal tumor formation, indicating that hair follicles are key sites for chemical carcinogen targeting in the skin.