TY - BOOK AU - Samar Hassan Zakaria Hassan AU - Dina Soliman Khater , AU - Heba Farag , TI - Immunohistochemical expression of mcm -2 in oral epithelial dysplasia = : اظهار المناعة الهيستوكيميائية ل (م س م ٢) فى عسر التنشؤ الفمى / PY - 2015/// CY - Cairo : PB - Samar Hassan Zakaria Hassan , KW - Grades of scc KW - P27 kip1 KW - Squamous cell carcinoma N1 - Thesis (M.Sc.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Oral Pathology; Issued also as CD N2 - Squamous cell carcinoma of the oral cavity is one of the most common neoplasms in the world which arises from oral mucosal lining that accounts for over 90% of all these tumors. There are several etiological factors of oral cancer including tobacco use, betel nut use, alcohol consumption, a diet poor in fresh fruit and vegetables, infective agents (candida, viruses), immune deficiency and exposure to sunlight in case of lip carcinoma. p27Kip1 is a member of a family of cyclin dependent kinase (CDK) inhibitors that bind to cyclin / CDK complexes and arrest cell division. There is considerable evidence that p27Kip1 plays an important role in multiple fundamental cellular processes, including cell proliferation, cell differentiation, and apoptosis. This study was performed to investigate the immunohistochemical expression of p27kip1in OSCC and to correlate this expression with different grades in order to evaluate its role in progression. Five, normal control cases where selected from paraffin blocks of mesenchymal where the normal surface epithelium was considered the normal control. Thirty cases of paraffin blocks were investigated in the study were 14 specimens well differentiated, 7 specimens moderately differentiated and 9 specimens were poorly differentiated OSCC. From all the paraffin blocks, tissue sections were cut and stained with haematoxylin and eosin stains (H and E), re-diagnosed to confirm the previously made diagnosis, classified according to WHO criteria (Pindborg et al., 1997). Other sections were cut and placed on positively charged slides (optiplus) ready for immunostaining procedures ER -