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Animals : an open access journal from MDPI2021; 11(7); 2121; doi: 10.3390/ani11072121

PD-L1/PD-1 and CTLA-4 Expression in Equine Penile Squamous Cell Carcinomas.

Abstract: In horses, penile squamous cell carcinomas (epSCCs) are among the most common cutaneous neoplastic lesions. These tumors usually arise in benign lesions such as viral plaques and papillomas frequently induced by papillomavirus type 2 (EcPV2) infection. In the last decade, the introduction of immune checkpoint inhibitors (ICI) for the treatment of human cancers has demonstrated promising results. Among the most commonly targeted pathways, there is PD-1/PD-L1 and CTLA-4. The aim of this study is to investigate the expression of the PD-1/PD-L1 pathway and CTLA-4 in the tumor microenvironment of epSCCs to assess the feasibility of an immunotherapeutic approach. Twenty equine epithelial tumors were retrospectively selected and submitted to RT-qPCR for PD-1 and PD-L1 genes. After testing antibodies cross-reactivity by western blotting, immunohistochemistry for PD-L1 and CTLA-4 was performed. Results from RT-qPCR demonstrated that 3/20 cases expressed the gene, whereas the gene was not detected. Immunohistochemical positivity for PD-L1 was found only in one case. CTLA-4-positive cells were observe in all cases but were few (Mdn = 4.8; IQR = 2.3-7.1 cells/HPF). In this study group, PD-1/PD-L1 and CTLA-4 do not appear to be highly expressed and therefore the use of ICI in epSCCs may not have promising rates of response.
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Publication Date: 2021-07-16 PubMed ID: 34359249PubMed Central: PMC8300259DOI: 10.3390/ani11072121Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article presents a study about the expression of PD-1/PD-L1 pathway and CTLA-4 in equine penile squamous cell carcinomas, with a view to determine the feasibility of using immune checkpoint inhibitors in the treatment of these types of cancer in horses.

Introduction

  • The article explains the prevalence of equine penile squamous cell carcinomas (epSCCs), a common type of skin cancer lesion in horses. These usually emerge from benign lesions like viral plaques and papillomas, often induced by a papillomavirus type 2 (EcPV2) infection.
  • In recent years, the development of immune checkpoint inhibitors (ICI) for human cancer treatment has shown promising outcomes. This study aims to investigate the use of these inhibitors in the treatment of epSCCs in horses.

Methodology

  • The researchers selected twenty equine epithelial tumors and performed RT-qPCR tests on the PD-1 and PD-L1 genes.
  • After carrying out tests on the cross-reactivity of antibodies using western blotting, they carried out immunohistochemistry for PD-L1 and CTLA-4.

Results and Conclusion

  • The analysis showed that out of the 20 cases, 3 expressed the PD-1 gene, while the PD-L1 gene was not detected.
  • The immunohistochemistry process showed PD-L1 presence in only one case, with CTLA-4-positive cells observed in all cases, though in limited numbers.
  • This study concludes that in this group, there is not a high expression of PD-1/PD-L1 and CTLA-4. Thus, the use of immune checkpoint inhibitors in the treatment of epSCCs may not offer high rates of success.

Cite This Article

APA
Porcellato I, Mecocci S, Brachelente C, Cappelli K, Armando F, Tognoloni A, Chiaradia E, Stefanetti V, Mechelli L, Pepe M, Gialletti R, Passeri B, Ghelardi A, Razzuoli E. (2021). PD-L1/PD-1 and CTLA-4 Expression in Equine Penile Squamous Cell Carcinomas. Animals (Basel), 11(7), 2121. https://doi.org/10.3390/ani11072121

Publication

Animals : an open access journal from MDPI
ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 11
Issue: 7
PII: 2121

Researcher Affiliations

Porcellato, Ilaria
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Mecocci, Samanta
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Brachelente, Chiara
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Cappelli, Katia
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
  • Centro di Ricerca sul Cavallo Sportivo, Università degli Studi di Perugia, 06126 Perugia, Italy.
Armando, Federico
  • Dipartimento di Scienze Medico-Veterinarie, Università degli Studi di Parma, 43100 Parma, Italy.
  • Pathology Institute, University of Veterinary Medicine, 30545 Hannover, Germany.
Tognoloni, Alessia
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Chiaradia, Elisabetta
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Stefanetti, Valentina
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Mechelli, Luca
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Pepe, Marco
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
  • Centro di Ricerca sul Cavallo Sportivo, Università degli Studi di Perugia, 06126 Perugia, Italy.
Gialletti, Rodolfo
  • Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
  • Centro di Ricerca sul Cavallo Sportivo, Università degli Studi di Perugia, 06126 Perugia, Italy.
Passeri, Benedetta
  • Dipartimento di Scienze Medico-Veterinarie, Università degli Studi di Parma, 43100 Parma, Italy.
Ghelardi, Alessandro
  • Azienda Usl Toscana Nord-Ovest, UOC Ostetricia e Ginecologia, Ospedale Apuane, 54100 Massa, Italy.
Razzuoli, Elisabetta
  • IZSLPV, Centro di Referenza di Oncologia Veterinaria e Comparata (CEROVEC), 16129 Genova, Italy.

Grant Funding

  • Grant 18C15 / Ministero della Salute

Conflict of Interest Statement

The authors declare no conflict of interest.

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This article has been cited 6 times.
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