Osteonecrosis of the jaw (ONJ) is a rare but serious adverse drug effect linked to long-term and/or high-dose exposure to nitrogen-bisphosphonates (N-BP), the standard of care for the treatment of bone fragility disorders. The mechanism leading to bisphosphonate-associated ONJ (BAONJ) is unclear and optimal treatment strategies are lacking. Recent evidence suggests that BAONJ may be linked to drug-induced immune dysfunction, possibly associated with increased susceptibility to infections in the oral cavity. The objective of this investigation was to comprehensively assess the relationship linking immune function, N-BP exposure, the oral microbiome and ONJ susceptibility. Leukocyte gene expression of factors important for immunity, wound healing and barrier function were assessed by real-time quantitative PCR and the oral microbiome was characterized by 454 pyrosequencing of the 16S rRNA gene in 93 subjects stratified by N-BP exposure and a history of ONJ. There were marked differences in the systemic expression of genes regulating immune and barrier functions including RANK (p = 0.007), aryl hydrocarbon receptor (AHR, p < 0.001), and FGF9 (p < 0.001), which were collectively up-regulated in individuals exposed to N-BP without ONJ relative to treatment controls. In contrast, the expression levels of these same genes were significantly down-regulated in those who had experienced BAONJ. Surprisingly, the oral microbiome composition was not directly linked to either BAONJ or N-BP exposure, rather the systemic leukocyte expression levels of RANK, TNFA and AHR each explained 9% (p = 0.04), 12% (p = 0.01), and 7% (p = 0.03) of the oral bacterial beta diversity. The oral microbiome is unlikely causative of ONJ, rather individuals with BAONJ lacked immune resiliency which impaired their capacity to respond adequately to the immunological stress of N-BP treatment. This may be the common factor linking N-BP and anti-RANK agents to ONJ in at-risk individuals. Preventive and/or therapeutic strategies should target the wound healing deficits present in those with ONJ.

The increased knowledge regarding HPV-infections in head and neck squamous cell carcinoma (HNSCC) has unexpectedly contributed to several uncertainties related to i) prevalence diversities depending on tumour site and geographical origin of the patients, ii) proportion of HPV-driven tumours among HPV-DNA-positive cases, and iii) identification of patients with HPV-attributed survival benefit. To investigate this heterogeneity, we analysed 307 HNSCC cases (tonsillar, n=135; non-tonsillar, n=172) from eight health care centers mostly from Northern Germany and determined HPV-DNA/mRNA and p16INK4A-status and combined results with the patient outcome. Overall HPV-DNA prevalence rate was 23.5% (72/307); attributed to: 43.7% (59/135) and 7.6% (13/172) tonsillar and non-tonsillar cases, respectively. Among these, 96.6% tonsillar and 38.5% non-tonsillar SCC were HPV-mRNA-positive. Although the study cohort was composed of patients from regions of rather close proximity, prevalence rates showed diversities of up to 40% in HNSCC subsite analysis with the lowest prevalence for tonsillar SCC in metropolitan areas (22.2%) vs. 50.9% in rural areas. Survival analysis identified p16INK4A alone as strongest predictor, followed by HPV-DNA-status alone or in combination with p16INK4A. This survival benefit was shown for tonsillar and non-tonsillar cases. Smoking significantly correlated with HPV-status, however, it does not influence survival when stratified for HPV. In conclusion, the data emphasize the urge for further data on HPV-infection in HNSCC to, e.g. clarify to what extent survival benefits of p16INK4A-positive patients are truly attributed to HPV-infections.

Human papillomaviruses (HPV) cause a subset of head and neck cancers (HNSCC). HPV16 predominantly signs responsible for approximately 10% of all HNSCC and over 50% of tonsillar (T)SCCs. Prevalence rates depend on several factors, such as the geographical region where patients live, possibly due to different social and sexual habits. Smoking plays an important role, with non-smoking patients being mostly HPV-positive and smokers being mostly HPV-negative. This is of unparalleled clinical relevance, as the outcome of (non-smoking) HPV-positive patients is significantly better, albeit with standard and not with de-escalated therapies. The results of the first prospective de-escalation studies have dampened hopes that similar superior survival can be achieved with de-escalated therapy. In this context, it is important to note that the inclusion of p16^INK4A (a surrogate marker for HPV-positivity) in the 8th TMN-classification has only prognostic, not therapeutic, intent. To avoid misclassification, highest precision in determining HPV-status is of utmost importance. Whenever possible, PCR-based methods, still referred to as the "gold standard”, should be used. New diagnostic antibodies represent some hope, e.g., to detect primaries and recurrences early. Prophylactic HPV vaccination should lead to a decline in HPV-driven HNSCC as well. This review discusses the above aspects in detail.

The aim of this study was to determine if micro-(mi-)RNAs are involved in the previously reported inverse correlation between the antileukoproteinase SLPI, HPV, and smoking habit of head and neck squamous cells carcinoma (HNSCC) patients. HPV-status and SLPI-protein expression were determined in tonsillar SCC (TSCC; n=126). Differentially expressed miRNAs dependent on HPV-status and SLPI-expression were detected by microarray; possible binding-sites in SLPI- and HPVE6-mRNAs were determined in silico. Survival rates were estimated testing prognostic values of HPV-status, SLPI- and miRNA-expression. miRNA-array identified 24 up-regulated and 10 down-regulated miRNAs in HPV-positive versus HPV-negative TSCC (p<0.01; HPV-positivity: 42.1%). HPV-positivity resulted in two up-regulated miRNAs in SLPI-positive TSCC. Of 16 further miRNAs, eight miRNAs were up- and eight were down-regulated in SLPI-negative TSCC. RT-q-PCR-validation of the four most differentially expressed miRNAs showed that miR-363 is expressed strongest in SLPI-negative/HPV-positive TSSC. In silico-analysis of all differentially expressed miRNAs identified miR-363, miR-210, miR-130a, and miR-181a with possible binding sites in the HPV16-E6-mRNA, but none were predicted in the SLPI-mRNA. HPV-positivity, low SLPI-levels and high miR-363-levels are significantly associated with better survival rates. The data presented here show that miR-363 is associated with HPV-positive/SPLI-negative TSCC. The prognostic value of miR-363 suggests a role in the assumed inverse correlation of smoking and SPLI-expression in the mode of HPV-infections in tonsillar but possibly also other HNSCC.

Previous studies describe a correlation between HPV-positivity and non-smoking in TSCC; p16^INK4A-expression as surrogate-marker for HPV-DNA/RNA-positivity is discussed controversially. In the present study, these parameters are assessed prospectively. HPV-status of sputum and tonsillar-swabs was analyzed to determine their validity as surrogate-marker for tissue-HPV-status. TSCC- (n = 52) and non-neoplastic tonsillar tissue (n = 163) were analyzed. HPV-DNA- and HPV-RNA-status of total sputum, cellular fraction and supernatants, tonsillar-swabs and -tissue was determined by (RT)-PCR. Immunohistochemistry determined p16^INK4A-expression. 23/163 (14.2%) non-neoplastic tonsils were HPV-DNA-positive; five patients (3 HPV16, 2 HPV11) had active HPV-infections (HPV-RNA-positive), in all biomaterials. 140/163 (85.9%) patients were either HPV-DNA-positive or HPV-DNA-negative in all samples. 21/52 (40.4%) TSCC-tonsils were HPV-DNA-positive; 17 patients were HPV-RNA-positive (14 HPV16; 4 HPV18). 40/52 (76.9%) TSCC-patients were congruent in all biomaterials. p16^INK4A-expression alone would have misclassified the HPV-status of 14/52 (26.2%) TSCC-patients. This prospective study confirms the discrepancy between HPV-status and p16^INK4A-expression and the significant correlation between non-smoking and HPV-DNA-positivity. HPV-sputum- and/or swab-results do not consistently match tissue-results, possibly having (detrimental) consequences if those were used to assess tissue-HPV-status. In the 5 patients with active HPV infection in the non-neoplasitic tonsils, tonsillectomy likely prevented subsequent development of TSCC.

Background: Recurrent respiratory papillomatosis (RRP) is a rare, non-malignant disease caused by human papillomavirus (HPV) types 6 and 11. The condition primarily affects the larynx, potentially leading to life-threatening airway obstruction. It is more aggressive in younger patients, necessitating frequent surgical interventions. This study investigates the therapeutic potential of the prophylactic HPV vaccine Gardasil^® in RRP patients, focusing on its impact on lesion size and the frequency of surgical interventions. Furthermore, a literature review was conducted to analyze the factors influencing the decision to vaccinate. Methods: A retrospective analysis was conducted on 63 RRP patients treated from 2008 to 2021. Disease burden was assessed using the Derkay score and the annual frequency of laser-surgical ablations. Comparisons were made between pre- and post-vaccination periods in vaccinated patients (n = 18), and between first and second halves of the disease’s course in unvaccinated patients (n = 14). Results: A reduction in the frequency of surgical interventions post-vaccination (p < 0.05) could be seen. The cumulated Derkay score per year decreased after second and third vaccination (p < 0.05). The decision to be vaccinated is influenced by multiple factors (e.g., potential side-effects, sociocultural factors, impact of social media, pre-existing conditions and the wider context of the recent pandemic). Conclusions: Gardasil^® appears to reduce the frequency of surgery and lessen disease severity in RRP patients, supporting the potential role of HPV vaccination as a therapeutic option for RRP. Moreover, it is crucial to overcome skepticism towards vaccinations to prevent the development of HPV-associated diseases in the first place.