Background and purpose
Canine mammary tumors are the most common tumor disease of female dogs, and adjuvant chemotherapy often
Conclusion
In summary, by using the canine mammary tumor cell line CMT-7364/S as the parental cell line, we successfully constructed a multidrug-resistant CMT-7364/R with high-dose drug pulse methods. Compared to its parental cell line, CMT-7364/R has decreased growth rate, overexpression of BCRP and increased migration and invasion ability due to EMT. The results of this study showed that CMT-7364/R might serve as a model for future studies on tumor drug resistance.
Methods
In this study, the canine triple negative breast cancer cell line CMT-7364 was induced to develop multidrug resistance using doxorubicin by high-dose drug pulse method. The drug resistance and the expression of drug transport pumps of the cells was verified by CCK8 assay, immunoblotting, qPCR and immunofluorescence. Next, we used scratch assay and Transwell invasion assay to compare the migration and invasion abilities of the two cell lines and examined the expression of EMT-related proteins in both using immunoblotting. The differences of transcriptome between parental and drug-resistant cell lines were detected by RNA-seq sequencing. Finally, mouse xenograft models of drug-resistant and parental cell lines were constructed to evaluate the tumorigenic ability.
Purpose
Canine mammary tumors are the most common tumor disease of female dogs, and adjuvant chemotherapy often
Results
After more than 50 generations of continuous passages stimulated by high-dose drug pulse method, the morphology of drug-resistant cell line CMT-7364/R tended to be mesenchymal-like and heterogeneous under light microscopy compared with the parental cell line CMT-7364/S, and developed resistance to doxorubicin and other commonly used chemotherapeutic drugs. In CMT-7364/R, BCRP was expressed at higher levels at both transcriptional and protein levels, while P-glycoprotein was not significantly different. Secondly, the migration and invasion ability of CMT-7364/R was significantly enhanced, with decreased expression of E-cadherin and increased expression of vimentin and mucin 1-N terminus. Finally, mouse xenograft models were constructed, while there was no significant difference in the volume of masses formed at 21 days.