Abstract
Prostate cancer (PCa) is the most common type of cancer among males. Although survival rate of early-stage PCa is high, treatment options are very limited for recurrent disease. In this study, the possible synergistic cytotoxic and apoptotic effect of octreotide in combination with AT-101 was investigated in DU-145 hormone and drug refractory prostate cancer cell line. To enlighten the action mechanisms of the combination treatment, expression levels of somatostatin receptors 2 and 5 (SSTR2 and SSTR5) were also investigated. Cell viability was measured by XTT assay. Apoptosis was assessed through DNA fragmentation analysis and caspase 3/7 assay. mRNA and protein levels of SSTR2 and SSTR5 were evaluated by qRT-PCR and western blot analysis, respectively. Octreotide in combination with AT-101 inhibited cell viability and induced apoptosis synergistically in DU-145 cells as compared to any agent alone. Combination treatment increased both SSTR2 and SSTR5 mRNA and protein levels in DU-145 cells. The data suggest that this combination therapy may be a good candidate for patients with advanced metastatic PCa do not respond to androgen deprivation.
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Degirmenci, M., Erdogan, A.P., Bulut, G. et al. Octreotide in combination with AT-101 induces cytotoxicity and apoptosis through up-regulation of somatostatin receptors 2 and 5 in DU-145 prostate cancer cells. Tumor Biol. 37, 4939–4944 (2016). https://doi.org/10.1007/s13277-015-4331-0
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DOI: https://doi.org/10.1007/s13277-015-4331-0