Human papillomavirus (HPV) types from the beta genus (beta-HPVs) have been implicated in the development of skin cancer. A potentially important aspect of their carcinogenic role is the ability of the E6 protein to degrade the proapoptotic family member Bak, which gives cells the ability to survive UV damage. However, it is unknown if the ability to degrade Bak is limited to certain beta-HPV types or whether E6 expression in keratinocytes affects other proteins important for apoptosis signaling. We tested the abilities of E6 proteins from several representative members of the beta-HPVs to degrade Bak and protect UV-treated keratinocytes from apoptosis. The E6 proteins of the beta-HPV type 5 (HPV5), -8, -20, -22, -38, -76, -92, and -96, as well as the alpha genus HPV HPV16, all degraded Bak or prevented its accumulation following UV treatment but did not degrade Bak constitutively. In addition, when tested using HPV16 E6 (16E6) and 8E6 as representative E6 proteins from the alpha and beta genera, respectively, Bak degradation was dependent on the E3 ubiquitin ligase, E6AP. Other important regulators of apoptotic signaling were examined and found to be unperturbed by the expression of the beta-HPV E6 proteins. Importantly, the expression of beta-HPV E6 proteins protected keratinocytes from apoptosis to the same extent as 16E6-expressing cells. In conclusion, several of the beta-HPV types possess the ability to protect UV-treated keratinocytes from apoptosis by reducing levels of Bak in those cells, thus blocking the intrinsic apoptotic pathway.Human papillomaviruses (HPVs) are small DNA tumor viruses that infect cutaneous and mucosal epithelia and disseminate by replication in terminally differentiated keratinocytes. So far, over 100 different types have been identified and characterized on the basis of DNA sequence analysis (12). Only a small number of these display a strong association with cancer development. Most notably, the high-risk types (16, 18, 31, 33, etc.) of alpha genus HPVs (alpha-HPVs) play a critical role in the development of cervical cancer. These same types have also been implicated in the majority of other anogenital cancers and a subset of head and neck carcinomas (11,43).Recently, the beta-HPVs, which cause cutaneous lesions in humans, have been linked to the development of skin cancers (32). The association between beta-HPVs and skin cancer was first identified in patients with the rare inherited disorder epidermodysplasia verruciformis (EV) (27). These individuals have a predisposition to the early development of disseminated, persistent flat warts and macular lesions following infection with a specific group of about 20 related beta-HPV genotypes, also known as EV types. About half of EV patients develop premalignant skin lesions and squamous cell carcinomas by age 40, primarily in sun-exposed areas (30). DNA from these lesions was found to harbor HPV genomes, suggesting a cocarcinogenic role of beta-HPVs and UV radiation in the early development of EV cancers (32). By use of sensitive P...

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Human papillomaviruses (HPVs) belonging to the Betapapillomavirus genus have recently been implicated in squamous cell carcinomas of the skin, though the mechanisms by which they initiate carcinogenesis are unclear. We show that human foreskin keratinocytes (HFKs) expressing several betapapillomavirus E6 (beta-E6) proteins display life span extension, but not to the extent seen in HFKs expressing HPV type 16 E6 (16E6). Additionally, we demonstrate that beta-E6 proteins can differentially activate telomerase. HFKs expressing 38E6 exhibit significant telomerase activity but to a lesser degree than that observed with 16E6; however, other beta-E6 proteins, including 5E6, 8E6, 20E6, and 22E6, exhibit low or background levels of telomerase activity. Utilizing glutathione S-transferase pull-down and coimmunoprecipitation experiments, the beta-E6 proteins were shown to interact with the cellular proteins E6-associated protein (E6AP) and NFX1-91, two proteins known to be important for telomerase activation by 16E6. Interestingly, the relative strength of the interaction between E6 and E6AP or NFX1-91 was proportionate to the activation of telomerase by each beta-E6 protein. To address the requirement for E6AP in telomerase activation by beta-E6 proteins, we utilized a shRNA to knock down endogenous levels of E6AP. Lysates with decreased levels of E6AP showed a reduced ability to activate telomerase, suggesting that E6AP is a necessary component. These data suggest that complex formation between E6, E6AP, and NFX1-91 is a critical step in mediating telomerase activation, which may be one contributing factor to cellular life span extension during human betapapillomavirus infection.High-risk human papillomaviruses (HPVs) belonging to the Alphapapillomavirus genus are known to be a common cause of cervical cancer through the function of the viral oncoproteins E6 and E7 (10,19,26). More recently, human betapapillomaviruses (beta-HPVs; such as HPV types 5, 8, and 38) have been implicated in skin cancer progression, yet the molecular mechanisms of cancer development are still largely unknown. BetaHPVs were first isolated from patients with the rare genetic disorder epidermodysplasia verruciformis, who suffer from life-long development of benign lesions such as warts but are also at greatly increased risk for development of squamous cell skin carcinomas (6-8). Cancers from patients with epidermodysplasia verruciformis led to the original isolation and identification of HPV type 5 (HPV5) and HPV8, whereas benign lesions from these patients contained dozens of different beta-HPV types (8). It is still unclear which, if any, betaHPVs can be categorized as high risk and what molecular functions are associated with high-risk phenotypes.Other evidence supporting a role for beta-HPVs in skin cancer includes previous reports that expression of HPV5 E6 (5E6) causes an inhibition of the intrinsic apoptotic cascade following UV light treatment (14,15). These studies have shown that Bak, a BH3-containing proapoptotic factor, is degraded by ...

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Objective: The purpose of this study was to find a correlation between closure technique in pharyngeal closure and outcomes of both pharyngocutaneous fistula and post-laryngectomy stricture after laryngectomy.Study Design: Retrospective Chart Review. Methods:We retrospectively reviewed a total of 151 patients over a 20-year period from January 1994 to December of 2013 who underwent primary pharyngeal reconstruction after total laryngectomy specifically looking at the closure technique in relation to pharyngo-cutaneous fistula (PCF) and post-laryngectomy stricture postoperatively. Patients were excluded based on secondary pharyngeal closure.Using logistic regression modelling, we performed univariate and multivariate analyses of our data. Results:The overall PCF and post-laryngectomy stricture rates were 19.1% and 15.8%. When salvage laryngectomy was excluded, t-type closure had a significantly lower risk of fistula rate (P=.038) compared to vertical closure. In multivariate analysis, this statistical significance was lost (P=.23); however, non-salvage t-type closure remained significantly better than both salvage laryngectomy groups (t-type, P=.033, vertical, P=.037), while non-salvage vertical closure had no significant difference from other groups. There was no difference in stricture rate between the two closure techniques (P=.63). Conclusion:Our study supports the role of t-type closure decreasing fistula rates in primary pharyngeal reconstruction. Orientation of the pharyngeal closure does not appear to change the risk of post-laryngectomy stricture formation after total laryngectomy. Salvage laryngectomy with primary pharyngeal reconstruction remains an independent risk factor for fistula formation.

BackgroundThe presence of a plane between the lingual tonsils and the underlying soft tissue has not been confirmed. The objective of this study is to ascertain the presence and the characteristics about this plane for surgical use.MethodsFive cadaver heads were obtained for dissection of the lingual tonsils. Six permanent sections of previous tongue base biopsies were reviewed. Robot assisted lingual tonsillectomy was performed using the dissection technique from the cadaver dissection.ResultsIn each of the 5 cadavers, an avascular plane was revealed deep to the lingual tonsils. Microscopic review of the tongue base biopsies revealed a clear demarcation between the lingual tonsils and the underlying minor salivary glands and muscle tissue. This area was relatively avascular. Using the technique described above, a lingual tonsillectomy using TORS was performed with similar findings from the cadaver dissections.ConclusionsA surgical plane for lingual tonsillectomy exists and may prove to have a role with lingual tonsillectomy with TORS.

Low-risk type human papillomavirus (HPV) 6 and 11 infection causes recurrent respiratory papillomatosis (RRP) and genital warts. RRP is the most common benign tumor of the larynx in children with frequent relapses. Repeated surgeries are often needed to improve vocal function and prevent life-threatening respiratory obstruction. Currently, there are no effective treatments available to completely eliminate these diseases, largely due to limited knowledge regarding their viral molecular pathogenesis. HPV E6 proteins contribute to cell immortalization by interacting with a variety of cellular proteins, which have been well studied for the high-risk type HPVs related to cancer progression. However, the functions of low-risk HPV E6 proteins are largely unknown. In this study, we report GST-pulldown coupled mass spectrometry analysis with low-risk HPV E6 proteins that identified sterile alpha motif domain containing 9 (SAMD9) as a novel interacting partner. We then confirmed the interaction between HPV-E6 and SAMD9 using co-immunoprecipitation, proximity ligation assay, and confocal immunofluorescence staining. The SAMD9 gene is down-regulated in a variety of neoplasms and deleteriously mutated in normophosphatemic familial tumoral calcinosis. Interestingly, SAMD9 also has antiviral functions against poxvirus. Our study adds to the limited knowledge of the molecular properties of low-risk HPVs and describes new potential functions for the low-risk HPV E6 protein.

Human papillomavirus (HPV)-related head and neck malignancies (HNMs) have become a serious health risk over the past 20 years. Despite decreases in non-HPV-related HNMs, the incidence of HPV-related HNMs has skyrocketed, and a new form of tumorigenesis is developing. HPV type 16 is the primary offender, and the majority of these tumors present in the oropharynx, with a smaller proportion in the larynx and oral cavity. While traditionally treated with surgery, the paradigm has shifted to more of a nonoperative chemoradiation therapy approach, with the hope of improving vital functions after therapy. Unfortunately, we continue to see significant dysphagia in these patients after treatment, and work is being done to improve outcomes. With the advent of transoral robotic surgery, we have again been able to reconsider treatment options for these patients, although it has been met with some skepticism and resistance. Here we discuss the scope of HPV-related HNMs, the treatment options and prognosis for the disease, and finally touch upon psychosocial issues related to HPV-related HNMs.