Selected Tumour Biomarker Levels in Sheep with Pulmonary Adenomatosis

Evaluation of the relationship between inflammatory reaction and interleukins in ovine pulmonary adenocarcinomas

In this study, it was aimed to investigate the association between inflammatory reaction of tumoral microenvironments with interleukin responses in ovine pulmonary adenocarcinomas (OPAs). Material of the study consisted of 26 sheep lung tissue samples being brought to the Pathology Department for routine diagnosis. Cases were collected between years 2009 - 2021; pre-diagnosis was based on clinical symptoms, anamnesis and gross lesion of the lungs. These tissues were designated in two groups as control (n = 6) and OPA (n = 20) groups. Choice of immunohistochemical staining was avidin-biotin peroxidase method. Reverse transcription polymerase chain reaction (RT-PCR) was used to confirm Jaagsiekte sheep retrovirus from paraffin-embedded tissues. On gross examination of OPAs, lesions seen were mostly in the caudal lobes of the lung, 1.00 - 2.00 cm in diameter as gray-white consolidated foci and in microscopic observation, tumor cells showed acinar, papillary or mixed growths. No expressions of interleukin (2 and 8) were observed in the control group. All OPAs cases were positive for interleukins (2 and 8) expressions. A total of eight tissue samples were detected as positives through RT-PCR. In conclusion, in this study, it was determined that interleukin-2 and interleukin-8 were produced from tumor microenvironment elements, especially tumor-associated macrophages, and these interleukins showed pro-inflammatory effects. Interleukins and the inflammatory reaction may promote the development of OPA.

Neoplasia-Associated Wasting Diseases with Economic Relevance in the Sheep Industry

We review three neoplastic wasting diseases affecting sheep generally recorded under common production cycles and with epidemiological and economic relevance in sheep-rearing countries: small intestinal adenocarcinoma (SIA), ovine pulmonary adenocarcinoma (OPA) and enzootic nasal adenocarcinoma (ENA). SIA is prevalent in Australia and New Zealand but present elsewhere in the world. This neoplasia is a tubular or signet-ring adenocarcinoma mainly located in the middle or distal term of the small intestine. Predisposing factors and aetiology are not known, but genetic factors or environmental carcinogens may be involved. OPA is a contagious lung cancer caused by jaagsiekte sheep retrovirus (JSRV) and has been reported in most sheep-rearing countries, resulting in significant economic losses. The disease is clinically characterized by a chronic respiratory process as a consequence of the development of lung adenocarcinoma. Diagnosis is based on the detection of JSRV in the tumour lesion by immunohistochemistry and PCR. In vivo diagnosis may be difficult, mainly in preclinical cases. ENA is a neoplasia of glands of the nasal mucosa and is associated with enzootic nasal tumour virus 1 (ENTV-1), which is similar to JSRV. ENA enzootically occurs in many countries of the world with the exception of Australia and New Zealand. The pathology associated with this neoplasia corresponds with a space occupying lesion histologically characterized as a low-grade adenocarcinoma. The combination of PCR and immunohistochemistry for diagnosis is advised.