Immunohistochemical detection of retinoid receptors in tumors from 30 dogs diagnosed with cutaneous lymphoma.
BACKGROUND
Retinoids exert their effects by binding to retinoid receptors. Two types of retinoid receptors have been described: retinoic acid receptor (RAR) and retinoid X receptor (RXR), and their subtypes α, β, and γ. The expression of subtypes varies depending on the disease process. This study intended to detect the pattern of retinoid receptor expression in cutaneous lymphomas in dogs.


OBJECTIVE
Cutaneous lymphomas in dogs have variable expression of retinoid and retinoid X receptors.


METHODS
Biopsy specimens from 30 dogs with cutaneous lymphoma.


METHODS
Tissues of dogs with cutaneous lymphoma were evaluated by immunohistochemistry for expression of retinoid receptors. The tissues were tested for the presence of 3 RAR and RXR subtypes (α, β, and γ). Lymphoma immunophenotype was determined by the use of the immunohistochemical markers CD79a (B-cell) and CD3 (T-cell) in all cases.


RESULTS
Twenty-nine of 30 dogs were CD3 positive. The retinoid receptors expressed with the greatest frequency were RARβ (87% of cases), and RXRα and RXRγ (77% of cases). The expression of RARγ was not observed.


CONCLUSIONS
Retinoid and rexinoid receptor binding drugs may have an impact on the treatment of dogs with cutaneous lymphoma.
de Mello Souza
C H
CH
College of Veterinary Medicine, Veterinary Medical Teaching Hospital, University of Missouri-Columbia, Columbia, MO, USA. souzac@missouri.edu
Valli
V E O
VE
Selting
K A
KA
Kiupel
M
M
Kitchell
B E
BE
D000818:Animals; D004283:Dog Diseases / Q000378:metabolism*; D004285:Dogs; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D007150:Immunohistochemistry / Q000662:veterinary*; D008223:Lymphoma / Q000145:classification / Q000378:metabolism / Q000662:veterinary*; D018168:Receptors, Retinoic Acid / Q000235:genetics / Q000378:metabolism*; D012878:Skin Neoplasms / Q000378:metabolism / Q000662:veterinary*
D018168:Receptors, Retinoic Acid