Assessment of the association between the frequency of micronucleus and p16INK4a/Ki-67 co-expression in patients with cervical intraepithelial lesions G Gashi1, V Mahovlić2, E Bahtiri3, F Kurshumliu1, A Podrimaj-Bytyqi1, IR Elezaj4 1
Department of Pathology, Faculty of Medicine, University of Prishtina, Prishtina, Kosovo, 2Department of Pathology and Cytology, Clinical Unit of Gynecological Cytology, University Hospital Center, Zagreb, Croatia, 3Department of Pharmacology, Faculty of Medicine, University of Prishtina, Prishtina, Kosovo, and 4Department of Biology, Faculty of Natural Sciences, University of Prishtina, Prishtina, Kosovo
ABSTRACT Human papilloma virus (HPV) infection is the main etiological factor for cervical intraepithelial lesions (CIN). An important characteristic of this process is the loss of genome stability. Therefore, it is imperative to use biomarkers of DNA damage caused by genomic instability to identify high risk individuals. We investigated the frequency of micronuclei (MN) in peripheral blood lymphocytes (PBL) of 20 patients, diagnosed as histologically CIN 1 and 10 healthy controls. We also examined the frequency of other nuclear anomalies including nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in PBL of patients with CIN 1 and healthy controls, and evaluated the benefits of p16INK4a and Ki-67 (p16INK4a/Ki-67) immunohistochemical double staining for identifying cervical squamous cells that express HPV E6/E7 oncogenes. We analyzed the association between the frequency of MN in PBL and the amount of p16INK4a/Ki-67 co-expression in CIN 1 patients to establish genomic instability. Among CIN 1 subjects, 15% exhibited diffuse p16INK4a/Ki-67 co-expression and were considered high positive, 25% of the CIN 1 cases exhibited p16INK4a/Ki-67 co-expression restricted to the lower part of the epithelium and were considered low positive and the remaining 60% of cases were negative. The frequency of MN, NPBs and NBUDs differed significantly among groups. We found a statistically significant positive correlation between p16INK4a/Ki-67 co-expression and the frequency of MN, NPBs and NBUDs in PBL. Our findings demonstrate the efficacy of p16INK4a/Ki-67 double immunostaining for histological samples with CIN 1. MN frequency in PBL might be useful for detecting genomic instability in cases of HPV infection and CIN. Key words: cervical intraepithelial lesions, co-expression, cytokinesis-block micronucleus cytome, double staining, genomic instability, human papilloma virus, Ki-67, micronucleus, p16INK4a
Human papilloma virus (HPV) infection is the principal cause of cervical intraepithelial lesions (CIN) (Zappacosta and Rosini 2008). Persistent
Correspondence: G Gashi Institute of Pathology, Faculty of Medicine, University of Prishtina “Hasan Prishtina,” Kosovo St “Bulevardi i Deshmoreve,” p.n. Prishtina 10 000, Kosovo. E-mail:
[email protected] © 2018 The Biological Stain Commission Biotechnic & Histochemistry 2018, Early Online: 1–9
DOI: https://doi.org/10.1080/10520295.2018.1462533
infections with human papillomavirus (HR-HPV) may cause CIN (Schiffman et al. 2007). HR-HPV E6 and E7 oncoproteins are essential for development of cervical lesions following persistent HPV lesions owing to their interaction with p53 and pRB tumor suppressor proteins (Ghittoni et al. 2010). A prerequisite for the shift from a clinically nonsymptomatic, transient HPV infection to transformation and maintenance of neoplastic growth of cells is the
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