Experimental Study On The Expression Of MDM2 Gene And P21 Gene In The Epidemis Of Expanded Skin

Objection: To provide evidence to elucidate the mechanism of tissue expansion by means of comparing the percentage of MDM2-positive and p21-positive epidermal cell of normal skin and expanded skin. To enlarge the clinical use of tissue expansion.Methods: We draw specimens from 3 parts of each same patient: the most expanded skin(A), border expanded skin(B), normal skin(B). There were 10 patients and 30 specimens. Then we compared the percentages of MDM2-positive and p21-positive cells in the 3 parts of skin: A, B, C from MDM2 and p21 Immunohistochemistry stained slices.Result: The average percentage of MDM2-positive cells in the stratum basale of epidemis of A is close to that of B , and lower than that of C , but the differences were not statistically significant; similarly, The average percentage of MDM2-positive cells in the middle layer of epidemis of A is close to that of B , and lower than that of C , but the differences were not statistically significant. The percentage of p21-positive cells in the middle layer of epidemis of B is higher than that of A , and lower than that of C .Conclusion: it seems a lower expression level of MDM2 gene in expanded epidermis than normal epidermis, but a higher expression level of p21 gene. MDM2 and p21 protein may be regulatory factors of tissue expansion.