Chalcones are interesting candidates for anti-cancer drugs due to the ease of their synthesis and their extensive biological activity. The study presents antitumor activity of newly synthesized chalcone analogues with a methoxy group on a panel of canine lymphoma and leukemia cell lines. The antiproliferative effect of the 2′-hydroxychalcone and its methoxylated derivatives was evaluated in MTT assay after 48 h of treatment in different concentrations. The proapoptotic activity was studied by cytometric analysis of cells stained with Annexin V/FITC and propidium iodide and by measure caspases 3/7 and 8 activation. The DNA damage was evaluated by Western blot analysis of phosphorylated histone H2AX. The new compounds had selective antiproliferative activity against the studied cell lines, the most effective were the 2′-hydroxy-2″,5″-dimethoxychalcone and 2′-hydroxy-4′,6′-dimethoxychalcone. 2′-Hydroxychalcone and the two most active derivatives induced apoptosis and caspases participation, but some percentage of necrotic cells was also observed. Comparing phosphatidylserine externalization after treatment with the different compounds it was noted that the addition of two methoxy groups increased the proapoptotic potential. The most active compounds triggered DNA damage even in the cell lines resistant to chalcone-induced apoptosis. The results confirmed that the analogues could have anticancer potential in the treatment of canine lymphoma or leukemia.

Treatment of neoplastic diseases in companion animals is one of the most important problems of modern veterinary medicine. Given the growing interest in substances of natural origin as potential anti-cancer drugs, our goal was to examine the effectiveness of benzyl isothiocyanate (BITC), a compound found in cruciferous vegetables, against canine lymphoma and leukemia. These are the one of the most common canine cancer types, and chemotherapy is the only treatment option. The study involved established cell lines originating from various hematopoietic malignancies: CLBL-1, GL-1, CLB70 and CNK-89, immortalized noncancerous cell lines: MDCK and NIH-3T3 and canine peripheral blood mononuclear cells (PBMCs). The cytotoxic activity of BITC, apoptosis induction, caspase activity and ROS generation were evaluated by flow cytometry. H2AX phosphorylation was assessed by western blot. The study showed that the compound was especially active against B lymphocyte-derived malignant cells. Their death resulted from caspase-dependent apoptosis. BITC induced ROS accumulation, and glutathione precursor N-acetyl-l-cysteine reversed the effect of the compound, thus proving the role of oxidative stress in BITC activity. In addition, exposure to the compound induced DNA damage in the tested cells. This is the first study that provides information on the activity of BITC in canine hematopoietic malignancies and suggests that the compound may be particularly useful in B-cell neoplasms treatment.

Background/Aim: Platinum-based drugs are a very potent class of anticancer drugs commonly used in anticancer therapy. However, resistance development and severe adverse effects make further research on new platinum derivatives necessary. In this study, cytotoxic activity of a new platinum(II) compound containing tris(2-carboxyethyl)phosphine (TCEP) ligand cis-[PtCl₂(TCEP)₂] was tested against canine lymphoma and leukemia cell lines and its activity was compared to that of cisplatin. Materials and Methods: Cells were exposed for 24 h to increasing concentrations of the studied compounds and cell viability was assessed by propidium iodide staining. Disturbances in apoptosis rate and cell cycle were also examined. Results: Cytotoxic activity of the new platinum complex cis-[PtCl₂(TCEP)₂] was higher compared to that of cisplatin and cell death was associated with apoptosis. However, the tested compound differently affected the cell-cycle progression than cisplatin. Conclusion: The cis-[PtCl₂(TCEP)₂] seems to be a potent anticancer agent, although further investigations are necessary to elucidate its biological activity.