farzaneh jalili,1,*
1. MSc of Biology-Genetics, Department of Genetics, Zanjan Branch, Islamic Azad University, Zanjan, Iran
Introduction: Papillomavirus genome is comprised of a small doublestranded and highly conserved DNA with an approximate size of 8000 base pairs and consists of three regions.that belonging to the Papovaviridae family. According to its genotypic nature, the HPV virus can lead to benign proliferative changes such as warts or cancers in different parts of the body. In the first case, the virus is considered a low-risk type and in the second case, it is considered a high-risk or cancerous type. About two hundred types of this type of virus are known, of which more than forty types are colonizing in the genital tract. For a more detailed explanation about the structure of the virus is that: There are six ealy proteins , three regulatory proteins (E1,E2, and E4) three oncoproteins (E5, E6, and E7)encoded in 4000 base pairs (bp) that participate in viral replication and transformation of cell . another 3000 bp region of dna molecule encodes two structural proteins L1 and L2 that compose the capsid of virus. the viral dna replication and transcriptional regulatory elements are controlled by long control region (LCR)that is encoded in a 1000 bp region .
Methods: the present literature review was performed using pubmed (national institute of health .ncbi.nlm.nih.gov/pubmed ) , scopus ( elsevier, scopus.com/scopus/home.url)and web of knowledge(thomson reuters,wok.mimas.ac.uk)electronic databases,and the following key words were searched : the role of human papiloma virus in cancer progression , viruse , human papilloma infection and cervical cancer . hpv molecular biology .several article were found in the surveyed databases and only the most relevant ones published in high impact factor journals and conducted by groups with recognized knowledge in the area were selected .
Results: HPVs can infect basal epithelial cells of the skin or inner lining of tissues and are categorized as cutaneous types or mucosal types. Cutaneous types of HPV are epidermitrophic and target the skin of the hands and feet. Mucosal types infect the lining of the mouth, throat, respiratory tract, or anogenital epithelium.most hpv infections are beneign and was first recognized as a cause of cutaneous warts such as planter , flat, common warts on the hands and feet . Benign types of the virus mainly include types6,11,42,43 and malignant types mainly include 16,18,31,33,34,35,39,45,51,52,56,58,59,66,68,70 those that lead to vulvar, anal, oral, penile, cervical, and oral cancers.
Conclusion: In most cases, the body removes this virus from the body without the person knowing, and the created warts also disappear. But in cases such as a weak immune system and high-risk types such as type 16and 18, smoking and long-term contact with this virus, this virus can cause cancer in the body. Prevention of high-risk behaviors and compliance with hygiene and periodic examinations in case of suspicious symptoms and use of condoms are ways to prevent contracting this virus.
Keywords: human papilloma virus, cancer, warts, benign , malignant