The characteristics of human papillomavirus DNA in head and neck cancers and papillomas

HPV genotyping and HLA II analysis in a pedigree study of pediatric RRP: preliminary results

OBJECTIVE

This preliminary pedigree study aims at the evaluation of HPV infection and HLA class II alleles as predictive markers in pediatric RRP.

METHODS

We investigated for HPV genotyping and HLA class II polymorphisms all the components of family nucleus where we detected a child born to an HPV infected mother and suffering from RRP.

RESULTS

HPV 11 was detected both in the laryngeal biopsies of two of the three affected babies and in the cervical smear of their mothers. The third child was positive for HPV 6 while his mother harboured a double HPV 6-16 infection. In one family, the HLA-DQB1*0501 allele exerted its protective role. The HLA-DQB1*0301 allele, commonly associated to a high grade of cervical neoplasia and HPV infection, was present in homozygous in one mother and her child. The same allele was found, though in a heterozygous form, in the third patient too.

CONCLUSION

Our report is the first attempt to use the pedigree study for the evaluation of HLA class II alleles and HPV infection related to pediatric RRP. This approach could identify genetic markers that may influence disease predisposition and the severity of HPV infection.

Four mutations in Epidermodysplasia verruciformis 1 (EVER1) gene are not contributors to susceptibility in RRP

OBJECTIVE

Epidermodysplasia verruciformis is a skin disease characterized by abnormal susceptibility to human papilloma viruses. Recently four mutations in the Epidermodysplasia verruciformis 1 gene (EVER1, also known as TMC6) have been associated with the disease. Because of the phenotypic similarity between Epidermodysplasia verruciformis and recurrent respiratory papillomatosis, we decided to investigate whether any of these mutations accounts for the susceptibility to human papilloma viruses in subjects with recurrent respiratory papillomatosis (RRP).

METHODS

Allele-specific PCR and restriction fragment length polymorphisms (RFLPs) were employed for genotyping a cohort of 101 patients with recurrent respiratory papillomatosis.

RESULTS

None of these four mutations were found in the studied subjects.

CONCLUSION

The absence of these mutations in RRP patients might indicate that EVER 1 alleles are not associated with susceptibility to RRP, or that other, as yet unidentified, mutations in the Epidermodysplasia verruciformis 1 gene, might account for the susceptibility to RRP.

Human Papillomaviruses and Genital Disease

Human papillomavirus (HPV) infection is causally related to several benign and malignant diseases of the anogenital tract. In this article the authors detail the epidemiology, methods of transmission and risk factors, pathogenesis, and oncogenesis of HPV, and describe clinical manifestations and current treatments. Special attention is given to condyloma acuminatum and non-cervical anogenital intraepithelial neoplasia. The authors conclude with the latest information on prophylactic vaccine development and prospects for future control of HPV-related disease.

Recurrent respiratory papillomatosis: pathogenesis to treatment

PURPOSE OF REVIEW

Recurrent respiratory papillomatosis remains a serious disease and is commonly treated by otolaryngologists. The goals of this review are to update physicians on current understandings regarding viral pathogenesis, patient risks, and current trends in treatment strategies.

RECENT FINDINGS

Surgical debulking still remains the foundation of treatment; however, newer surgical approaches utilizing microdebriders are replacing laser ablation. Genetic studies have identified individuals with specific immune cell alleles to be at greater risk for persistent infection. Our understanding of the viral pathogenesis has increased by the identification of a viral mechanism to downregulate antigen expression in cells infected with human papillomavirus, thus possibly allowing decreased immune detection. Although the viral types responsible for recurrent respiratory papillomatosis have been identified, the mechanism by which they alter cellular growth has not been identified. Research studies investigating adjuvant medical therapies aimed at reducing required surgical therapy intervals and possibly helping cure the infection are being completed. A safe, effective adjuvant therapy is still currently not available.

SUMMARY

Improved surgical approaches have slightly enhanced patient care; however, more research is needed to understand how human papillomavirus causes disease so that these therapies can be developed.

The role of human papilloma virus infection in the etiology of oropharyngeal carcinoma

PURPOSE OF REVIEW

Evidence is growing that human papilloma virus is responsible for a subset of head and neck carcinomas. This review analyzes the history and current thinking regarding this relatively new etiologic agent of squamous cell carcinoma.

RECENT FINDINGS

Research over the past year has confirmed that human papilloma virus is associated with subset of head and neck squamous cell carcinoma, especially tumors arising from the tonsil. Human papilloma virus 16 is the most common strain found in these tumors. Most studies also indicate that patients with human papilloma virus infection are more likely to have a better prognosis, engage in riskier sexual behavior, and have a history of less tobacco and alcohol consumption than patients who have human papilloma virus-negative tumors. Not all studies confirm these findings, however, and human papilloma virus, even the high-risk strains (16, 18, and 33) are found in a certain percentage of healthy individuals.

SUMMARY

Human papilloma virus (especially strain 16) has been recognized as a probable etiologic agent for some head and neck squamous cell carcinomas. Most commonly, human papilloma virus is associated with tumors arising from the tonsillar epithelium. Because a definitive causal relationship is still to be identified, current research aims to delineate the specific mechanism whereby human papilloma virus produces squamous cell carcinoma. It is hoped that a vaccine may be produced in the near future that will serve as adjuvant therapy for patients with human papilloma virus-positive tumors.