2015 ACVIM Forum Research Abstract Program

There were 71 Greyhounds treated; 19 dogs received metronomic chemotherapy after completing standard chemotherapy, and 52 received only suramin/doxorubicin protocol. Three dogs still alive and the one that died due to an unrelated cause were censored for the DFI and ST analyses. There was no significant difference in DFI or ST when dogs treated with chemotherapy alone were compared with those treated with chemotherapy plus metronomic chemotherapy. DFI was 202 days for the Chemotherapy group and 154 days for the Chemotherapy and Metronomic group (p = 0.54). Survival time was 279 days fro the Chemotherapy and 237 days for the Chemotherapy and Metronomic group (p = 0.88). Osteotropic neoplasms including feline oral squamous cell carcinoma (OSCC), and canine prostatic carcinoma (PC), oral malignant melanoma (OMM) and osteosarcoma (OS) are managed with ionizing radiation therapy, yet treatment responses are not durable. NQO1 is a detoxifying enzyme overexpressed in human tumors, but remains uncharacterized in veterinary oncology. Deoxynyboquinone (DNQ) is a potent substrate for NQO1, and results in reactive oxygen species generation with consequent cell death. We hypothesize that NQO1 will be expressed by osteotropic solid tumors and serve as druggable target for improving the cytotoxic activities of radiation therapy.