دورا محتملا لفيروس ابشتاين بار في عملية تسرطن الغدة الدرقية الحليمية == A Possible Role Of Epstein - Barrvirus In Carcinogenesis Of Papillary Thyroid Carcinoma
Author name:
هند علي خميس
Supervisor name:
عامر رشيد النجار | سعد حسن محمد علي
General topic:
Medicine
Specific topic:
Microbiology
Degree:
Doctorate
University:
Mustansiriyah University
Language:
English
University location:
Baghdad
First pages:
19T1154 - p.pdf
Abstract:
This study was designed as a retrospective research. A total number of (90) formalin - fixed, paraffin embedded tissues were studied. Malignant and normal thyroid tumors tissue blocks were collected from the archives of histopathology laboratories of different general hospital including ALYarmouk Teaching Hospital (Baghdad), Baghdad Medical City Teaching Hospital as well as many private laboratories in Baghdad, during the period from May 2013 to May 2014. These cases include ? Thirty tissue specimens from patients with papillary thyroid cancer. ? Thirty tissue specimens with benign thyroid lesions as control thyroid tissues group. ? Thirty (30) thyroid specimens were obtained from the normal thyroid tissues from the same those totally - thyroidectimized patients for thyroid papillary cancer (PTC) and have served as the second control group for this study. This study was therefore a paired case - control design. The sections were stained by hemotaxyline and eosin staining so as to confirm the diagnosis and assure that the intervening sections ( that were specified for the in situ hybridization and Immunohistochemistry study have containing the questioned tissues from papillary thyroid cancers and benign thyroid tissues (control group).After histopathological sectioning of these thyroid gland tumors and staining by Hematoxylin and Eosin, a final definitive diagnosis was done by histopathologist consultant. The practical part of this study was designed in four pathways : 1. Molecular detection of Epstein - Barr virus in those tissue blocks were performed by using ultra - sensitive version of in situ hybridization (ISH) for detection of EBV - EBERs. 2. To perform immunohistochemical study to demonstrate EBV - latent gene (LMP1, EBNA - 2) in the papillary thyroid cancer compared to control group. 3. To perform immunohistochemical screening study to demonstrate the over expression state of p53 - tumor suppressor gene in those tissues with papillary thyroid cancer compared to control group. 4. To perform immunohistochemical screening study to detected the CD8 and CD56 in tissues with papillary thyroid cancers compared to control group. The obtained results are summarized as follows : 1. The mean age of patients with papillary thyroid cancer and simple nodular goiter was (39.87&41.13) years respectively, with standard deviation ±(11.773,9.243) years. 2. In this study, the percentage of the females with papillary thyroid cancer was higher (86.7%; 26 cases) than the percentage of their PTC - male counter parts (13.3%; 4 cases). The patients whom sub totally thyroidectimized for simple noduler goiters , the percentage of females was also higher (73.3%; 22 cases) than the percentage of their male counter parts with simple noduler goiters ( 26.7%; 8cases). Female / male ratios of the patients with PTC and simple noduler goiters were 6.5 and 2.75 respectively. 3. The percentage of EBV results in the total group of PTC was (50%) while the percentage in the total group of normal thyroid tissue was (26.7%) and lastly in the total simple nodular goiter group was (10.0%). 4. The positivity rate of EBV EBERs - ISH technique in the total group of PTC was (30%), where as its percentage in NTT tissues was (16.7%) and in SNG tissues was (3.3%). 5. The percentage of positive - EBNA - 2 IHC technique in the total group of PTC was (20%), where as its percentage in NTT tissues was (10.0%) and in SNG tissues was (6.7%). 6. The percentage of positive - EBV - LMP - 1 - IHC technique in the total group of PTC was (43.3%), where as its percentage in NTT tissues was (20.0%) and in SNG tissues was (6.7%). 7. Mutated P53 - protein was detected in 28 cases (70%) of the studied cases. Twelve cases (30.0 %) showed negative IHC reactions. 8. The highest total percentage of CD8 - IHC reactions (21 cases; 70%) was found in those with papillary thyroid cancer followed by normal thyroid tissues cases ( 5 cases; 16.7%) and then ( 2 cases : 6.7%) in simple nodular goiter. 9. It was found that the highest percentage of CD56 - IHC reactions was in those with normal thyroid tissues (25 cases; 83.3%) followed by an equal percentages of CD56 - IHC reactions in either thyroid papillary or simple nodular goiter (2 positive cases; 6.7%, each). 10. The importance of CD56 marker has been found to play a role or it may be better to be used as a negative - diagnostic biomarker for papillary thyroid cancer in differentiating it from other malignancies as well as benign lesions of the thyroid gland, individually as well as in combination with other markers for clinical evaluation of those patients. 11. The evident high mutated p53 - over expression, as reflected by abnormal gene product, among papillary thyroid cancer patients indicates for a pivotal role of such genetic mutation in their carcinogenesis as well as could be useful in the clinical evaluation of patients with papillary thyroid cancer, too. 12. The high coexistence of p53 - mutation with EBV in PTC could point for participation of EBV - transformation genes in the p53 activation in high proportion of PTC. 13.The high percentage of CD8 lymphocytes in EBV - positive PTC as compared to their EBV - negative counterparts could reflect the participation of specific cellular immunity against both, the papillary thyroid cancers and this EBV infection during the initiation and progression of EBV - associated papillary thyroid cancers.
