Podoplanin Expression in Canine Melanoma.

Area of Science:

• Veterinary Pathology
• Cancer Biology
• Immunohistochemistry

Background:

• Podoplanin (PDPN) is a type I transmembrane protein found in normal cells like lymphatic endothelial cells and pulmonary type I alveolar cells.
• A previously developed anti-canine PDPN monoclonal antibody (mAb), PMab-38, recognizes PDPN in canine squamous cell carcinomas but not in normal lymphatic endothelial cells.

Purpose of the Study:

• To investigate the reactivity of the PMab-38 antibody with canine melanoma.
• To explore the potential utility of PMab-38 in understanding PDPN's role in canine melanomas.

Main Methods:

• Immunohistochemistry was employed to assess the reaction of PMab-38 with canine melanoma tissues.
• Comparison of PMab-38 staining in melanoma tissues versus normal tissues, including lymphatic endothelial cells.

Main Results:

• PMab-38 demonstrated reactivity with 90% (9/10 cases) of canine melanoma cells.
• In melanoma tissues, PMab-38 also stained lymphatic endothelial cells and cancer-associated fibroblasts.
• Crucially, PMab-38 did not stain lymphatic endothelial cells in normal tissues.

Conclusions:

• The monoclonal antibody PMab-38 shows significant reactivity with canine melanoma.
• PMab-38's differential staining in tumor tissues compared to normal tissues suggests its potential as a diagnostic marker.
• This antibody may be a valuable tool for further research into the function of podoplanin in canine melanoma.