The ‘Trojan horse’ oncogenic strategy of HPVs in childhood

Molecular evidence of human papillomaviruses in the retinoblastoma tumor

Retinoblastoma tumor (RB) is one of the most prevalent ocular cancers among children. RB may be caused by inherited mutations in RB1 gene as well as some environmental risk factors. Human papillomaviruses (HPV) are suspected as a risk factor of RB due to their pRb inactivating protein. This study evaluated the molecular prevalence of HPV among the RB tumor specimens in Iran. The RB tumor samples were tested for detection of HPV-L1 gene using a nested-PCR approach, and then followed by sequencing and phylogenetic analysis to reveal HPV types. Overall, there were 61 RB tumor samples; 54/61 (88.5%) had unilateral and 7/61 (11.5%) bilateral RB; 55/61 cases (90.2%) had sporadic non-familial RB tumor. HPV-DNA was detected in 6/61 (9.8%) of patients' tumors; the HPV positive RB cases all had unilateral and unfamiliar sporadic RB tumor. HPV type 16 was the most prevalent type identified across the RB tumor samples (3/61, 4.9%). The rate of detected HPV among the RB specimens seems to be considerable. Further investigations are required to elucidate the exact association between HPV and progression to RB.

The paediatric story of human papillomavirus (Review)

Human papillomavirus (HPV) is composed of a particularly heterogeneous family of DNA viruses, which has gained much attention in recent years due to the discoveries of Professor Harald zur Hausen, who first identified a connection between HPV and cervical cancer. Professor Harald zur Hausen, the 'Father of HPV Virology', was the recipient of the 2008 Nobel Prize. HPV can be transmitted through physical contact via autoinoculation or fomites, sexual contact, as well as vertically from the HPV-positive mother to her newborn, causing subclinical or clinical infections. In infancy and childhood, HPV-associated clinical infections include skin warts, genital warts and juvenile recurrent respiratory papillomatosis, while cervical squamous intraepithelial lesions have also been reported among adolescent girls. To date, several research teams, worldwide, have extensively investigated HPV from the paediatric point of view. This primitive effort has been performed before the recent great expansion of paediatric HPV research due to the vaccination programmes against HPV, which were introduced into clinical practice in 2006. In this review article, we present a brief overview of paediatric HPV research after the first report in 1978 involving children in the research of HPV until the time point of this great expansion. In the future, it is expected that further unresolved issues will be addressed and clarified, as the paediatric story of HPV remains a challenging research target.