Peer-reviewed veterinary case report
ABC-transport proteins linked to chemo resistance in dog mammary
By Honscha, K U et al.·Published in Reproduction in domestic animals = Zuchthygiene·2009·Institute of Veterinary Physiology, Germany·View original on PubMed →
PetCaseFinder translated the abstract of this peer-reviewed paper into plain English so pet owners can read it. We do not publish original research — every detail traces back to the citation above. How we work →
Original publication title: Expression of ABC-transport proteins in canine mammary cancer: consequences for chemotherapy.
- Species:
- dog
Plain-English summary
A study found that many dogs with mammary cancer have a protein that makes chemotherapy less effective. In 103 samples of canine mammary tumors, almost all showed high levels of certain proteins that help cancer cells resist drugs like doxorubicin, which is commonly used for treatment. This means that using doxorubicin may not work well for these dogs. The findings suggest that veterinarians might need to consider other treatment options for dogs with this type of cancer to improve outcomes.
People also search for: dog mammary cancer treatment · doxorubicin for dogs · why is my dog's cancer not responding to treatment
Abstract
Intrinsic or acquired drug resistance is a major barrier for chemotherapy of cancer. Importantly, the presence of ATP-binding cassette, ABC-transport proteins in tumour cells circumvents an intracellular accumulation of chemotherapeutic drugs. In this study, 103 canine mammary tumour probes were investigated for mRNA expression of seven ABC-transporters by RT-PCR. All tumour samples expressed multidrug resistance-associated protein 1 (MRP1) and breast cancer resistance protein (BCRP). MRP7 was detected in 97.1% of tumour probes, MRP3 in 96.1%, Pgp in 92.2%, MRP5 in 85.4% and MRP6 in 64.1%. More of the half of tumour samples (56.1%) expressed all of the examined ABC-transport proteins. Approximately one-third of the tumour samples (32.7%) were lacking in one transporter and only 11.2% possessed from three to five transporters. The canine transporter cBCRP was functionally analysed in stable transfected Madin-Darby canine kidney-II cells using an MTT viability test. cBCRP transfected cells showed a 5.4-fold resistance to 10 microm doxorubicin. Cell survival in the presence of methotrexate was not affected by cBCRP. In conclusion, absence of efficiency of chemotherapy of canine mammary cancer can be caused by expression of seven various ABC-transport proteins. Because cBCRP is expressed in all examined tumour probes and induces resistance to doxorubicin, the application of doxorubicin for treatment of canine mammary is inappropriate.
Find similar cases for your pet
PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.
Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/19754573/