부산대학교 도서관

Introduction Benign tumors of adipose tissue are often exhibited in humans with rare phosphatase and tensin homolog (PTEN) Hamartoma Tumor Syndrome (PHTS), which is caused by heterozygous germ line mutations [...]
Adipose tissue tumors (lipomas) frequently develop in patients with heterozygous germ line phosphatase and tensin homolog (PTEN) mutations, simvastatin has been demonstrated to exhibit antitumor effects, and so the aim of the present study was to assess the effects of simvastatin on the growth of human PTEN haploinsufficient lipoma cells. Whether the effects of simvastatin in lipomas are mediated via PTEN upregulation was also assessed. The results of the present study revealed that simvastatin treatment reduced cell viability and induced apoptosis in human lipoma cells. Furthermore, it was demonstrated that the expression of cellular PTEN mRNA and protein was increased following simvastatin stimulation. In addition, the phosphorylation of protein kinase B and downstream targets of mammalian target of rapamycin and 4E-binding protein (4E-BP)-1 was attenuated. It was also demonstrated that simvastatin induced PTEN transcriptional upregulation by increasing peroxisome proliferator-activated receptor (PPAR)[gamma] expression. The small interfering RNA-mediated knockdown of PPAR[gamma] abrogated the stimulatory effect of simvastatin on the PTEN protein, but did not influence apoptosis. The results of the present study suggest that simvastatin may be beneficial for patients with inoperable PTEN haploinsufficient lipomas. Key words: human adipocytes, phosphatase and tensin homologue, protein kinase B, simvastatin, peroxisome proliferator-activated receptor [gamma], phosphatase and tensin homologue hamartoma tumor syndrome, lipomatous overgrowth