Objective We examined the expression of p53R2 in melanoma and evaluated whether p53R2 is involved in the growth and proliferation of melanoma cells.
Methods We examined the clinicopathological significance of p53R2 in melanoma. To investigate the role of p53R2 in melanoma we used KHm5 and KHm6 melanoma cells that express p53R2, and p53R2-targeting small interfering (si) RNA.
Results p53R2 expression was detected immunohistochemically in 56 of 78 patients (71.8 % ). The expression of p53R2 was significantly correlated with the depth of invasion and the tumor stage. p53R2-targeting siRNA successfully knocked down p53R2 and significantly inhibited the growth of KHm5 and 6 cells. Moreover, 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.
Conclusions We propose p53R2 as a therapeutic target to enhance the effectiveness of chemotherapy in patients with p53R2-positive melanoma.