Interaction between doxorubicin and amniotic membrane stem cells on the canine inflammatory mammary cancer cell line IPC-366

The aim of this study was to evaluate the efficiency of doxorubicin, canine amniotic membrane stem cells (AMC) and the association between them in the triple-negative canine inflammatory mammary cancer cell line IPC-366. Experiments were carried out for 72 hours in 4 groups: IPC-366 untreated cells; cells treated with 10mg/mL of doxorubicin; coculture IPC-366 cells with 10 5 AMC; and cells treated with doxorubicin+AMC. MTT assays were performed for evaluating proliferation; flow cytometry to analyze hormonal and angiogenesis markers, and anti-inflammatory cytokines; and EIA techniques were used to evaluate secretion of steroid hormones (progesterone (P4); dehydroepiandrosterone (DHEA); androtenedione (A4); 17β-estradiol (E2); estrone sulphate (SO4E1)) in cell culture media. Results showed that cells treated with 10 mg/mL of doxorubicin resulted in a reduction of 71.64% on cell proliferation at 72h of treatment. A reduction in the expression of VEGF and PCNA-3 was observed by flow cyotmetry in treated cells compared to control cells. Differences on IL-10 were found within groups: treatment with doxorubicin resulted in a reduction on IL-10 expression although in AMC group expression remained similar to control group. Estrogen intracellular levels were significantly increased in doxorubicin+AMC group (4.67% vs. 27.1%). Regarding steroid hormone secretion, in AMC treated group any differences in hormone levels were found compared to control group. P4 and E2 secretion resulted in an increase in doxorubicin-treated group although in doxorubicin+AMC group these levels decreased with respect to control group. DHEA secretion was significantly decreased in treated groups compared to control group. Interestingly, A4 and SO4E1 secretion levels showed a significant increase compared to control group. Collectively, these results suggest that combination of doxorubicin and AMC caused a synergy that alters the cancer cell9s secretion hormone profile by accumulation of estrogens. These findings attempt to give an approach of the combination of well-known treatments and amniotic stem cells as a canine mammary tumors therapy. Citation Format: Jessica Borghesi, Sara Caceres, Lara C. Mario, Rafael Goncalves Hayashi, Laura Pena, Angela Alonso-Diez, Maria J. Illera, Gema Silvan, Maria A. Miglino, Ana C. Oliveira Carreira, Phelipe Oliveira Favaron, Juan C. Illera. Interaction between doxorubicin and amniotic membrane stem cells on the canine inflammatory mammary cancer cell line IPC-366 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1161.