Among other abnormalities that occur frequently in tumors, inactivation of the tumor suppressor genes PTEN and VHL can lead
to increased VEGF production. Inactivation of PTEN occurs in canine HSA providing cells a growth advantage within their microenvironment.
VHL regulates various distinct pathways that converge on endothelial cell proliferation under hypoxic conditions. Currently
investigations are underway on how mutations of this gene influence the pathogenesis of HSA in dogs. These are but two potential
targets that could be used to develop highly specific approaches with no or acceptable toxicity to treat HSA in its early
stages, offering new hope for dogs that develop this disease.
Dr. Hoskins is owner of DocuTech Services. He is a diplomate of the American College of Veterinary Internal Medicine with
specialities in small animal pediatrics. He can be reached at (225) 955-3252, fax: (214) 242-2200, or e-mail: