Comparison of serum 25(OH) vitamin D, parathormone and immunity marker concentrations between dogs with transmissible venereal tumour and healthy dogs

Abstract

Background1,25‐Dihydroxyvitamin D (1,25(OH)2 D) is vital in the homeostasis of calcium and bone health as well as in the prevention of many disorders such as neoplasms. Epidemiological data show that low concentrations of both 1,25(OH)2D and its precursor 25(OH) vitamin D (25(OH)D) are associated with an increased risk of a variety of human tumours.ObjectivesTo investigate 25(OH)D, parathormone (PTH) and immunity marker concentrations in dogs with transmissible venereal tumour (TVT).Methods25(OH)D, PTH and various biochemical and immunity markers were evaluated in dogs with TVT (n = 26) and in healthy (n = 30) dogs.Results25(OH)D concentrations were significantly lower in dogs with TVT in comparison with healthy dogs. In contrast, PTH, immunoglobulin G and interleukin (IL)‐9 concentrations were higher in the dogs with TVT. Other variables, including IL‐10, interferon γ, calcium and inorganic phosphate, were not statistically different between the two groups.ConclusionsDecreased serum 25(OH)D concentration may be a risk factor for the development of canine TVT; however, cause‐and‐effect remains incompletely understood. Further studies are required to elucidate the exact role of 25(OH)D in canine TVT and whether vitamin D supplementation may be useful prophylactically or as an adjunct to chemotherapy.

Vitamin D status in female dogs with mammary gland tumors

“…Afterward, PTH stimulates 1alpha‐hydroxylase activity, ultimately increasing calcitriol synthesis with a subsequent increase in intestinal calcium and phosphorus absorption. 7 However, in our study, reduced vitamin D concentrations were not observed. Parathyroid hormone could also have a direct influence on the biology of breast tumors.…”

“…The present study did not support any association between lower 25‐hydroxyvitamin D concentrations and mammary cancer in bitches as has been demonstrated in dogs with other types of neoplasia. 4 , 5 , 6 , 7 , 9 , 10 …”

“…An inverse relationship between 25‐hydroxyvitamin D and PTH in transmissible venereal tumors is apparent. 7 Dogs with transmissible venereal tumors have lower concentrations of vitamin D and higher concentrations of PTH. These increased PTH concentrations could be explained as compensatory response to low vitamin D concentrations which reduce intestinal calcium absorption and stimulate PTH secretion.…”

“…A relationship between vitamin D status and nonskeletal diseases exists in dogs, 3 including lower serum 25‐hydroxyvitamin D (calcidiol) concentrations in dogs with lymphoma, 4 splenic hemangiosarcoma, 5 mast cell tumor, 6 and transmissible venereal tumor, 7 but not osteosarcoma. 8 Plasma 25‐hydroxyvitamin D concentrations are lower in dogs with B‐cell lymphoma but not T‐cell lymphoma, mast cell tumor, and osteosarcoma when compared with healthy dogs.…”