Expression of Oct4 Protein in Astrocytic Tumours: Histopathologic and Immunohistochemical Study
Published: November 1, 2018 | DOI: https://doi.org/10.7860/JCDR/2018/35035.12276
Menar M Al-Sayed Ayoub, Samar Abdel-Moneim Al-Sheikh, Lubna Omar Al-Farouk Abdel-Salam, Engy Samir Mohamed Abdel-Moneim Al-Hariry
1. Professor, Department of Pathology, Faculty of Medicine, Cairo University, Cairo, Egypt.
2. Assistant Professor, Department of Pathology, Faculty of Medicine, Cairo University, Cairo, Egypt.
3. Assistant Professor, Department of Pathology, Faculty of Medicine, Cairo University, Cairo, Egypt.
4. PhD Student, Department of Pathology, Faculty of Medicine, Cairo University, Cairo, Egypt.
Correspondence
Engy Samir Mohamed Abdel-Moneim Al-Hariry,
16 Fatma Roshdy St-Al-Haram-Giza-Floor 5, Apartment 603, Cairo, Egypt.
E-mail: drengy2008@hotmail.com
Introduction: The majority of gliomas in adults are resistant to therapy. Therapy resistance has been attributed to the presence of Cancer Stem Cells (CSCs). Oct4 is a transcription factor required for maintaining the pluripotency and self-renewal of CSCs. It was found to be highly expressed in astrocytomas and other tumours.
Aim: Assessment of immunohistochemical expression of Oct4 protein, being a target antigen for cancer immunotherapy of astrocytic tumours, and the correlation between Oct4 expression and the grades of astrocytoma.
Materials and Methods: In this retrospective cross-sectional study, 66 paraffin-embedded biopsies of astrocytomas were collected including; 12 cases of Grade I, 19 cases of Grade II, 15 cases of Grade III and 20 cases of Grade IV. All the cases were studied immunohistochemically using anti-Oct4 protein antibody. Chi-square test or Fisher’s-exact test was used to examine the relationship between qualitative variables. All tests were two-tailed. The p-value <0.05 was considered significant.
Results: Oct4 was expressed in 30 cases. The higher the grade of astrocytoma, the more was the expression (p-value=0.006) and the percentage of positive tumour cells (p-value=0.039). The expression was both nuclear and cytoplasmic. The intensity of expression was variable within the same tumour. Oct4 was not expressed in normal brain tissue.
Conclusion: Oct4 is a stem cell marker that is involved in the development of CSCs, and accordingly, the development of many tumours including astrocytomas.
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