Tumor Biology

, Volume 37, Issue 4, pp 4939–4944 | Cite as

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

  • Mustafa Degirmenci
  • Atike Pinar Erdogan
  • Gulcan Bulut
  • Harika Atmaca
  • Selim Uzunoglu
  • Burcak Karaca
  • Bulent Karabulut
  • Ruchan Uslu
Original Article


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.


AT-101 Octreotide Cell viability Apoptosis SSTR2 and SSTR5 


Compliance with ethical standards

Conflicts of interest

The authors declare no conflict of interest.


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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2015

Authors and Affiliations

  • Mustafa Degirmenci
    • 1
  • Atike Pinar Erdogan
    • 2
  • Gulcan Bulut
    • 2
  • Harika Atmaca
    • 3
  • Selim Uzunoglu
    • 4
  • Burcak Karaca
    • 2
  • Bulent Karabulut
    • 2
  • Ruchan Uslu
    • 2
    • 5
  1. 1.Department of Internal Medicine, School of MedicineTepecik Research and Education HospitalIzmirTurkey
  2. 2.Department of Medical Oncology, School of MedicineEge UniversityIzmirTurkey
  3. 3.Department of Biology, Faculty of Science and LettersCelal Bayar UniversityManisaTurkey
  4. 4.Department of Medical Biology, School of MedicineCelal Bayar UniversityManisaTurkey
  5. 5.Tulay Aktas Oncology HospitalEge University School of MedicineBornovaTurkey

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