Expression of p53R2 significantly correlates with the depth of invasion and the tumor stage in melanoma, new research shows. (J Dermatol Sci; 68(1):19-24) Furthermore, use of siRNA targeting p53R2 successfully knocked down p53R2 and significantly inhibited the growth of KHm5 and 6 cells. The degree of KHm5 and 6 cell growth inhibition was greater in the presence of both p53R2-targeting siRNA and nimustine (ACNU) than with ACNU alone, suggesting that p53R2 silencing enhanced the chemosensitivity of KHm5 and 6 cells to ACNU. Findings come from research that examined the expression of p53R2 in melanoma and evaluated whether p53R2 is involved in the growth and proliferation of melanoma cells. Researchers used KHm5 and KHm6 melanoma cells that express p53R2, and p53R2-targeting small interfering (si) RNA. p53R2 expression was detected immunohistochemically in 56 of 78 patients (71.8 percent).