High drug efflux pump capacity and low DNA damage response induce doxorubicin resistance in canine hemangiosarcoma cell lines

• Published in: Research in veterinary science Vol. 127; pp. 1 - 10
• Main Authors: Morita, Atsuya, Aoshima, Keisuke, Gulay, Kevin Christian Montecillo, Onishi, Shinichi, Shibata, Yuki, Yasui, Hironobu, Kobayashi, Atsushi, Kimura, Takashi
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2019; Elsevier Limited
• Subjects: Animals; Antineoplastic Agents - pharmacology; Apoptosis; Ataxia; Biological Transport; Biotechnology; Cancer; Cancer therapies; Cell culture; Cell cycle; Cell Line, Tumor; Cervical cancer; Chemotherapy; Damage; Deoxyribonucleic acid; DNA; DNA Damage; DNA damage response; Dog Diseases - genetics; Dog Diseases - metabolism; Dogs; Doxorubicin; Doxorubicin - pharmacology; Drug resistance; Drug Resistance - physiology; Efflux; Hemangiosarcoma; Hemangiosarcoma - genetics; Hemangiosarcoma - metabolism; Invasiveness; Kinases; Laboratories; Medical prognosis; Metastases; Tumors; Veterinary medicine; United States > US; Japan; Hemangiosarcoma; Drug resistance; DNA damage response; Doxorubicin; Apoptosis; Cancer
• ISSN: 0034-5288; 1532-2661
• DOI: 10.1016/j.rvsc.2019.09.011

Canine hemangiosarcoma (HSA) is an aggressive malignant endothelial tumor in dogs and characterized by poor prognosis because of its high invasiveness, high metastatic potential, and poor responsiveness to anti-cancer drugs. Although doxorubicin-based chemotherapy is regularly conducted after surgical treatment, its effects on survival rates are limited. Acquisition of drug resistance is one of the causes of this problem, but the underlying mechanisms remain unclear. In the present study, we aimed to identify the drug-resistance mechanism in canine HSA by establishing doxorubicin-resistant (DR) HSA cell lines. HSA cell lines were exposed to doxorubicin at gradually increasing concentrations. When the cells were able to grow in the presence of a 16-fold higher doxorubicin concentration compared with the initial culture, they were designated DR-HSA cell lines. Characterization of these DR-HSA cell lines revealed higher drug efflux pump capacity compared with the parental cell lines. Furthermore, the DR-HSA cell lines did not show activation of the DNA damage response despite carrying high DNA damage burdens, meaning that apoptosis was not strongly induced. In conclusion, canine HSA cell lines acquired doxorubicin resistance by increasing their drug efflux pump capacity and decreasing the DNA damage response. This study provides useful findings to promote further research on the drug-resistance mechanisms in canine HSA. •Doxorubicin-resistant canine HSA (DR-HSA) cell lines were established.•DR-HSA cell lines had higher drug efflux pump capacity than their parental cells.•DNA damage response in DR-HSA cells was inactivated.•Apoptosis was not strongly induced in DR-HSA cell lines.