Lymphoma is the most common blood cancer in both dogs and humans. It affects approximately 20-100 in every 100,000 dogs and without treatment, canine lymphoma can be fatal within 1-2 months.
The most common treatment of the disease is using chemotherapy drugs, including vincristine and doxorubicin. Unfortunately, these drugs are not always effective as cancer cells can become resistant to treatment. A study from Auburn University in Alabama has shown that a diet with fatty acids can improve the function of chemotherapy drugs against canine lymphoma.
Canine lymphoma accounts for 25% of all canine cancers and affects B cells and T cells, which are an integral part of the immune system. As mentioned above, lymphoma is aggressively targeted using chemotherapy drugs like vincristine and doxorubicin.
Even with treatment, relapses are frequently observed with this type of cancer. Chemoresistance is usually due to the cancer cells upregulating drug transporters, which shuttle chemo drugs back out of the cell, reducing their efficacy.
In previous studies, fatty acids have been shown to improve the effectiveness of chemotherapy drugs. It was hypothesized by the scientists at Auburn University that stearidonic fatty acid found in fish, seed oil and algae could enhance the effectiveness of cancer drugs by reducing the number of anti-drug transporters in cancer cells.
What they did
The scientists tested the efficacy of chemo drugs against lymphoma tumours and health canine blood cells, both on their own and in combination with a fatty acid called stearidonic acid. Three different types of canine lymphoid tumours were treated using Doxorubicin (DOX), Vincristine (VCR) or DOX + stearidonic acid and VCR + stearidonic acid. Some cells were also left untreated as a control.
After treatment, the cells were then tested for viability (if the cell is alive and functioning) and the number of drug transport proteins.
What they found
From the study, the researchers found that there were 2 types of cells (OSW T-cell and 17-71 B-cell lymphoid-tumor cells) that were less sensitive to the chemotherapy drugs than the other cells. The addition of stearidonic acid to the chem drugs greatly promoted the antitumor action of VCR and DOX in both of these cells. It was determined that the stearidonic acid bound and inhibited the drug transporters on the cancer cells. This increased the sensitivity of the cancer cells to the chemotherapy drugs.
Take home message
This study showed that fatty acids, in combination with chemotherapy drugs can improve canine recovery from chemo resistant lymphoma.