Clinical-histopathological and molecular study of ovine pulmonary adenocarcinoma in Awassi sheep in Al-Qadisiyah Province, Iraq

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.

Mutation and up-regulation of TP53 in ovine pulmonary adenocarcinoma lung cells as a model of human lung cancer

Ovine pulmonary adenocarcinoma (OPA) is a model of human lung cancer‎ and fatal viral disease that causes neoplasia in sheep respiratory cells. ‎In the current study, 986 lung samples was inspected in the slaughterhouse, and finally twenty OPA ‎ lung organs were clinically diagnosed and five healthy lung organs were assigned as the control sample. Three SSCP patterns were detected for the affected lungs animals in comparison with the healthy lungs. In addition, sequencing results indicated three different single point mutations in exon 4 of TP53 within infected lungs, whereas no mutations were observed in exon 9 of this gene. Real-time PCR results showed up-regulation of the TP53 gene in all the infected lung cells compared to healthy cells. There was significant correlation between the mutations in exon 4 and OPAand can be used as a useful tool in determining the mechanism of lung cancer.

Assessment of MDA and 8-OHdG expressions in ovine pulmonary adenocarcinomas by immunohistochemical and immunofluorescence methods

This study aimed to reveal the presence of reactive oxygen species (ROS)-induced lipid peroxidation and DNA damage in ovine pulmonary adenocarcinomas (OPA) by evaluating malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHdG) expressions by immunohistochemical and immunofluorescence methods. Lung tissue samples were collected from 26 sheep brought to the Pathology Department for routine diagnosis. Lung tissues were fixed in 10% neutral buffered formalin, following routine procedures tissues were stained with hematoxylin and eosin. Avidin-Biotin Peroxidase method was used as immunohistochemical staining. Indirect immunofluorescence method was applied to the sections. Tumoral cells showed acinar, papillary or mixed type patterns. Only 2 of 20 cases metastasized to regional lymph nodes. All OPAs were immune positive for Jaagsiekte Sheep Retrovirus Capsid Protein (JSRV CA), MDA and 8-OHdG. The control group was negative for JSRV CA, MDA and 8-OHdG expressions. Malondialdehyde and 8-OHdG immune positive cells were statistically increased in the OPA group compared to the control group. In conclusion, our results demonstrate that higher MDA and 8-OHdG expressions in sheep with OPA suggest that OPA may be closely related to lipid peroxidation and oxidative DNA damage.