Relationship between persistent HPV infection and cervical carcinoma

Human papillomavirus (HPV) genital infection is a very common sexual transmitted disease. Mostly, the infection is transient and asymptomatic. The induction of effective immune responses usually allows the infection to be spontaneously cured. However, the infection sometimes can be responsible for an intraepithelial lesion, which may progress to be cervical cancer. Cervical cancer is one of the most common neoplastic diseases affecting women. It is clear that carcinogenic HPV infection is the necessary process for the development of cervical cancer. HPV infection is very frequent in young women aged less than 25 years and viral clearance lasts for 8 months in average. This clearance is the consequence of host immunity intervention, which leads to spontaneous regression of infection and the overwhelming majority of low-grade squamous intraepithelial lesions (more than 80% within a period of 2 years). The major factor, which permits the progression to high grade squamous intraepithelial lesions and invasive cervical cancer, is the persistent feature of HPV infection. HPV infection is usually transient, but several factors were identified as host factors (genetic, immunodepression, oral contraception and smoking) and viral factors (genotype, variants, viral load and integration) to increase the persistence. Cervical cancer is clearly the first virus-induced solid tumor discovered in human. Furthermore, it represents a woman death cause that can be avoided.