Durvalumab with or without tremelimumab versus the EXTREME regimen as first-line treatment for recurrent or metastatic squamous cell carcinoma of the head and neck: KESTREL, a randomized, open-label, phase III study.

BACKGROUND: Patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) have a poor prognosis. The phase III KESTREL study evaluated the efficacy of durvalumab [programmed death-ligand 1 (PD-L1) antibody] with or without tremelimumab [cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) antibody], versus the EXTREME regimen in patients with R/M HNSCC. PATIENTS AND METHODS: Patients with HNSCC who had not received prior systemic treatment for R/M disease were randomized (2 : 1 : 1) to receive durvalumab 1500 mg every 4 weeks (Q4W) plus tremelimumab 75 mg Q4W (up to four doses), durvalumab monotherapy 1500 mg Q4W, or the EXTREME regimen (platinum, 5-fluorouracil, and cetuximab) until disease progression. Durvalumab efficacy, with or without tremelimumab, versus the EXTREME regimen in patients with PD-L1-high tumors and in all randomized patients was assessed. Safety was also assessed. RESULTS: Durvalumab and durvalumab plus tremelimumab were not superior to EXTREME for overall survival (OS) in patients with PD-L1-high expression [median, 10.9 and 11.2 versus 10.9 months, respectively; hazard ratio (HR) = 0.96; 95% confidence interval (CI) 0.69-1.32; P = 0.787 and HR = 1.05; 95% CI 0.80-1.39, respectively]. Durvalumab and durvalumab plus tremelimumab prolonged duration of response versus EXTREME (49.3% and 48.1% versus 9.8% of patients remaining in response at 12 months), correlating with long-term OS for responding patients; however, median progression-free survival was longer with EXTREME (2.8 and 2.8 versus 5.4 months). Exploratory analyses suggested that subsequent immunotherapy use by 24.3% of patients in the EXTREME regimen arm contributed to the similar OS outcomes between arms. Grade 3/4 treatment-related adverse events (TRAEs) for durvalumab, durvalumab plus tremelimumab, and EXTREME were 8.9%, 19.1%, and 53.1%, respectively. CONCLUSIONS: In patients with PD-L1-high expression, OS was comparable between durvalumab and the EXTREME regimen. Durvalumab alone, and with tremelimumab, demonstrated durable responses and reduced TRAEs versus the EXTREME regimen in R/M HNSCC.

Human papillomavirus-related oropharyngeal cancer.

High-risk human papillomavirus (HPV) is now recognised as the principal cause of the increasing incidence rates of oropharyngeal squamous cell carcinoma (OPSCC) in some parts of the world. The primary risk factor for developing HPV-related OPSCC is oral HPV-infection and the majority of oral HPV-infections are acquired by oral sex. Progression into an OPSCC includes persistent infection with evasion of immune response in the microenvironment, the activation of viral early genes (E6, E7) in basal epithelial cells, the deregulation of cell cycle and the accumulation of chromosomal instability. Patients affected by HPV-related OPSCC tend to be younger and have better outcomes. This observation has lead current research to evaluate treatment de-escalation options to reduce long-term associated morbidity. Moreover, a different molecular profile for HPV-related OPSCC has been described, opening new options for targeted therapy and immunotherapy approaches. This paper comprehensively reviews our accumulated knowledge regarding the role of HPV in OPSCC spanning from infection to cancer development, including its clinical diagnosis, management and preventive strategies.

HPV knowledge gaps and information seeking by oral cancer patients.

OBJECTIVES: The incidence of human papillomavirus (HPV) positive oral squamous cell carcinoma (OSCC) continues to increase over time, challenging healthcare providers to address their patients' HPV-related concerns. MATERIALS AND METHODS: This prospective study assessed health literacy, HPV knowledge, utilization and trust in information sources among patients with incident HPV-positive or HPV-negative OSCC diagnosed at the Ohio State University from 2011 to 2015. Health literacy was assessed with a standardized scale. Additional questions evaluated HPV knowledge (including transmission, prevalence, health consequences and treatment), the frequency and type of information sources sought, and trust in those sources. RESULTS: Surveys were collected from 372 OSCC cases (HPV-positive, n=188; HPV-negative, n=184). Despite high mean health literacy scores, only 45.2% of HPV-related knowledge questions were answered correctly. HPV was known to be a sexually transmitted infection and a cause of cervical and anal cancer by 66.0%, 56.5% and 15.2%, respectively. In all domains, cases with HPV-positive OSCC were significantly more informed than HPV-negative cases (for all, p<0.01). Only 52.7% and 56.2% of patients with HPV-positive OSCC felt they knew enough to be comfortable discussing HPV with their doctor or sexual partner, respectively. The most frequently used information source was the internet (80.9%), which ranked 8th in trust of 15 possible sources. Although most (95.5%) patients trusted information from their doctors, only 37.9% used doctors as an information source. CONCLUSIONS: Doctors are a highly trusted, but infrequent utilized, information source and should facilitate patient access to high-quality HPV information sources.

Low etiologic fraction for human papillomavirus in larynx squamous cell carcinoma.

BACKGROUND: Human Papillomavirus (HPV) is a cause of oropharyngeal squamous cell carcinoma (OPSCC), but its pathogenic role in larynx squamous cell carcinoma (LSCC) remains unclear. MATERIAL AND METHODS: A single-institutional, retrospective case-series was performed to estimate the etiological fraction (EF) for HPV in LSCC. Eligible cases included 436 consecutive cases of LSCC diagnosed (2005-2014) at The Ohio State University Medical Center. HPV DNA presence was detected by consensus primer PCR (Inno-LiPa) and HPV type-specific qPCR. HPV E6/E7 mRNA expression was detected by type-specific qRT-PCR. Tumor p16 expression was evaluated by immunohistochemistry (IHC). RESULTS: HPV DNA was detected by Inno-LiPa in 54 of 404 (13.4%, 95% CI 10.2-17.1) evaluable samples but was confirmed by HPV type-specific qPCR in only 14 (3.5%, 95% CI 1.9-5.7). Only 7 of 404 (1.7%, 95% CI 0.7-3.5) LSCC were positive for HPV E6/E7 mRNA expression, including HPV16 (n=4) and 1 each for 11, 26 and 33. In the HPV11-positive tumor, Sanger sequencing discovered 6 nucleotide mutations in the upstream regulation region, E6 and E7. Of 404 LSCC, 18 had strong and diffuse p16 expression. In comparison to a gold standard of HPV E6/E7 mRNA expression, p16 expression had a sensitivity of 71.4% (95% CI 29.0-96.3), specificity of 96.7% (95% CI 94.5-98.3), positive-predictive-value (PPV) of 27.8% (95% CI 9.7-53.5) and negative-predictive-value of 99.5% (95% CI 98.1-99.9). CONCLUSION: The EF for HPV in LSCC is low (1.7%) in a geographic region with high EF for OPSCC. Low-risk HPV may rarely cause LSCC. Finally, p16 expression has poor PPV for HPV in LSCC.

DEK promotes HPV-positive and -negative head and neck cancer cell proliferation.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and patient outcomes using current treatments remain poor. Tumor development is etiologically associated with tobacco or alcohol use and/or human papillomavirus (HPV) infection. HPV-positive HNSCCs, which frequently harbor wild-type p53, carry a more favorable prognosis and are a biologically distinct subgroup when compared with their HPV-negative counterparts. HPV E7 induces expression of the human DEK gene, both in vitro and in vivo. In keratinocytes, DEK overexpression is sufficient for causing oncogenic phenotypes in the absence of E7. Conversely, DEK loss results in cell death in HPV-positive cervical cancer cells at least in part through p53 activation, and Dek knockout mice are relatively resistant to the development of chemically induced skin papillomas. Despite the established oncogenic role of DEK in HPV-associated cervical cancer cell lines and keratinocytes, a functional role of DEK has not yet been explored in HNSCC. Using an established transgenic mouse model of HPV16 E7-induced HNSCC, we demonstrate that Dek is required for optimal proliferation of E7-transgenic epidermal cells and for the growth of HNSCC tumors. Importantly, these studies also demonstrate that DEK protein is universally upregulated in both HPV-positive and -negative human HNSCC tumors relative to adjacent normal tissue. Furthermore, DEK knockdown inhibited the proliferation of HPV-positive and -negative HNSCC cells, establishing a functional role for DEK in human disease. Mechanistic studies reveal that attenuated HNSCC cell growth in response to DEK loss was associated with reduced expression of the oncogenic p53 family member, ΔNp63. Exogenous ΔNp63 expression rescued the proliferative defect in the absence of DEK, thereby establishing a functional DEK-ΔNp63 oncogenic pathway that promotes HNSCC. Taken together, our data demonstrate that DEK stimulates HNSCC cellular growth and identify ΔNp63 as a novel DEK effector.

Human papillomavirus-associated head and neck squamous cell carcinoma: mounting evidence for an etiologic role for human papillomavirus in a subset of head and neck cancers.

There is increasing molecular and epidemiologic evidence that human papillomavirus (HPV) is associated with a distinct subset of head and neck squamous cell carcinomas. The strength and consistency of HPV DNA presence in oropharyngeal cancers bolster the argument that this association is likely causal. HPV-positive tonsillar cancer in particular is emerging as a specific disease entity with distinct molecular, pathologic, and clinical characteristics. Recent data suggest that the incidence of tonsillar carcinoma in the United States is increasing, despite a decline in tobacco use, supporting the existence of other important risk factors such as HPV infection. Individuals with a history of an HPV-associated anogenital cancer and HIV-infected men are at increased risk for tonsillar carcinoma. This review focuses on the recent literature (since 1998) investigating the relationship between HPV and head and neck cancer development, using the current paradigm for causal inference in epidemiologic research attributed to Sir A. Bradford Hill. Data examining the association of HPV with pathogenesis of head and neck squamous cell carcinoma before 1999 were previously reviewed in this journal.

Detection and quantitation of human papillomavirus (HPV) DNA in the sera of patients with HPV-associated head and neck squamous cell carcinoma.

The human papillomavirus (HPV) has been implicated as an etiological factor in a subset of head and neck squamous cell carcinoma (HNSCC). Because circulating tumor DNA has previously been detected in the sera of patients with advanced HNSCC (stage III or IV), we hypothesized that HPV DNA might be present in the sera of HPV-positive HNSCC patients. Serum DNA extracts from 70 patients with HNSCC were screened for HPV using conventional PCR and a real-time quantitative assay. All samples subjected to conventional PCR were further tested by dot blot hybridization, and positives were confirmed by Southern blotting. Paired tumor DNA from archived tissues was then similarly screened for HPV genomic material (n = 51) or tested by in situ hybridization (n = 19). HPV-16 DNA was detected with L1 primers in 0 of 65 sera and in 15 of 70 (21%) tumors. Conventional PCR with E7 primers and Southern blot hybridization detected HPV-16 DNA in four (6%) sera. Using real-time quantitative PCR, six samples were found to contain various levels of circulating HPV DNA (mean, 12 copies/ml; range, <1-35.) All six serum-positive patients had corresponding tumors positive for E7. Four of these patients with HPV-positive tumors later developed distant metastases, suggesting that HPV DNA in serum may represent occult hematogenous spread of cancer cells in this subset of patients. Although a much larger prospective trial is required, the presence of HPV genomic material in serum DNA of HPV-positive HNSCC patients may serve as a useful marker of early metastatic disease.

Evidence for a causal association between human papillomavirus and a subset of head and neck cancers.

BACKGROUND: High-risk human papillomaviruses (HPVs) are etiologic agents for anogenital tract cancers and have been detected in head and neck squamous cell carcinomas (HNSCCs). We investigated, retrospectively, an etiologic role for HPVs in a large series of patients with HNSCC. METHODS: Tumor tissues from 253 patients with newly diagnosed or recurrent HNSCC were tested for the presence of HPV genome by use of polymerase chain reaction (PCR)-based assays, Southern blot hybridization, and in situ hybridization. The viral E6 coding region was sequenced to confirm the presence of tumor-specific viral isolates. Exons 5-9 of the TP53 gene were sequenced from 166 specimens. The hazard of death from HNSCC in patients with and without HPV-positive tumors was determined by proportional hazards regression analysis. RESULTS: HPV was detected in 62 (25%) of 253 cases (95% confidence interval [CI] = 19%-30%). High-risk, tumorigenic type HPV16 was identified in 90% of the HPV-positive tumors. HPV16 was localized specifically by in situ hybridization within the nuclei of cancer cells in preinvasive, invasive, and lymph node disease. Southern blot hybridization patterns were consistent with viral integration. Poor tumor grade (odds ratio [OR] = 2.4; 95% CI = 1.2- 4.9) and oropharyngeal site (OR = 6.2; 95% CI = 3.1-12.1) independently increased the probability of HPV presence. As compared with HPV-negative oropharyngeal cancers, HPV-positive oropharyngeal cancers were less likely to occur among moderate to heavy drinkers (OR = 0.17; 95% CI = 0.05-0.61) and smokers (OR = 0.16; 95% CI = 0.02-1.4), had a characteristic basaloid morphology (OR = 18.7; 95% CI = 2.1-167), were less likely to have TP53 mutations (OR = 0.06; 95% CI = 0.01-0. 36), and had improved disease-specific survival (hazard ratio [HR] = 0.26; 95% CI = 0.07-0.98). After adjustment for the presence of lymph node disease (HR = 2.3; 95% CI = 1.4- 3.8), heavy alcohol consumption (HR = 2.6; 95% CI = 1.4-4.7), and age greater than 60 years old (HR = 1.4; 95% CI = 0.8-2.3), all patients with HPV-positive tumors had a 59% reduction in risk of death from cancer when compared with HPV-negative HNSCC patients (HR = 0.41; 95% CI = 0.20-0.88). CONCLUSIONS: These data extend recent molecular and epidemiologic studies and strongly suggest that HPV-positive oropharyngeal cancers comprise a distinct molecular, clinical, and pathologic disease entity that is likely causally associated with HPV infection and that has a markedly improved prognosis.

Larynx preservation in head and neck cancers. A discussion of the National Comprehensive Cancer Network Practice Guidelines.

The management of advanced cancers of the larynx and hypopharynx has become increasingly complex as different treatment modalities, including surgery, radiation, and chemotherapy, have been combined with the goal of improving local disease control and disease-specific survival. A union of 17 comprehensive cancer centers in the United States, the National Comprehensive Care Network (NCCN), was formed in 1995 to promote state-of-the-art cancer care. To achieve this goal, multidisciplinary panels of experts from member institutions have created disease-specific practice guidelines for the evaluation and treatment of cancer patients, including those with head and neck cancers. Although detailed analysis of surgical methods and radiation techniques are beyond the scope of this article, the evolving laryngeal preservation strategies for patients with advanced, resectable hypopharyngeal or laryngeal (including supraglottic and glottic) cancers are reviewed using relevant sections of the NCCN practice guidelines as a framework for discussion.

Human papillomavirus in head and neck squamous cell carcinoma: are some head and neck cancers a sexually transmitted disease?

There is abundant epidemiologic and virologic evidence that high-risk human papillomaviruses (HPVs) are tumorigenic in human epithelia, particularly in the cervix, where HPV infection is necessary for cancer development. HPV DNA has been detected in a proportion of head and neck squamous cell carcinomas (HNSCCs) in numerous case series. The mere presence of the virus in tumor specimens, by itself, does not imply a causal relationship. However, recent studies support an etiologic role for HPVs in a subset of HNSCC, particularly poorly differentiated tumors arising from Waldeyer's tonsillar ring. Epidemiologic studies have shown that exposure to HPV increases the risk of HNSCC, and HPV infection may interact with alcohol and tobacco exposure in tumor promotion. Molecular studies indicate that transcriptionally active virus is confined to tumor cells. It will be important to clarify further the role that HPV has in HNSCC development, because HPV-based therapeutic vaccines which are currently being developed for cervical cancer may also be of benefit in the management of HNSCC.

Human herpesvirus-8.

Our current understanding of Kaposi's sarcoma (KS) has evolved from initial descriptions of this "idiopathic sarcoma" to a progressively detailed characterization of its probable infectious origin. This article traces the explosive discovery of human herpesvirus-8 (HHV-8) and its etiologic associations with KS, Castleman's disease, and primary effusion lymphomas. A framework for understanding how viral infection leads to development of these unusual disease is presented. The possible role of HHV-8 in tumorigenesis, through viral manipulation of signal transduction pathways and cell cycle control, is discussed.

Karyoplasmic interaction selection strategy: a general strategy to detect protein-protein interactions in mammalian cells.

We describe a strategy and reagents for study of protein-protein interactions in mammalian cells, termed the karyoplasmic interaction selection strategy (KISS). With this strategy, specific protein-protein interactions are identified by reconstitution of the functional activity of the yeast transcriptional activator GAL4 and the resultant transcription of a GAL4-regulated reporter gene. Reconstitution of GAL4 function results from specific interaction between two chimeric proteins: one contains the DNA-binding domain of GAL4; the other contains a transcriptional activation domain. Transcription of the reporter gene occurs if the two chimeric proteins can form a complex that reconstitutes the DNA-binding and transcriptional activation functions of GAL4. Using the KISS system, we demonstrate specific interactions for sequences from three different pairs of proteins that complex in the cytoplasm. In addition, we demonstrate that reporter genes encoding cell surface or drug-resistance markers can be specifically activated as a result of protein-protein interactions. With these selectable markers, the KISS system can be used to screen specialized cDNA libraries to identify novel protein interactions.

Discrimination between related DNA sites by a single amino acid residue of Myc-related basic-helix-loop-helix proteins.

A yeast genetic system was developed to study how the basic regions of basic-helix-loop-helix (bHLH) proteins distinguish between related consensus bHLH binding sites, with nucleotide sequence CANNTG. The yeast bHLH protein CBF1 binds to the sequence CAC(A/G)TG found in the yeast centromere element CDE1 and in promoter regions of several yeast genes involved in methionine biosynthesis. Using a functional assay to rescue a mutant cbf1 yeast strain from methionine auxotrophy, we determined that the basic region of CBF1 could be replaced by the homologous region of either the vertebrate USF transcription factor or c-Myc, both of which bind CACGTG. The homologous region of the AP4 transcription factor, which recognizes the sequence CAGCTG, could not functionally replace the CBF1 basic region. However, only a single substitution, Met----Arg, in the AP4 basic region of the inactive chimera CBF-AP4 was sufficient to restore CBF1 function. In randomization experiments, only arginine or lysine provided functional substitutions at the AP4 methionine position. The results suggest that this conserved arginine residue in the basic regions of Myc-related bHLH proteins discriminates between CAC(A/G)TG and related sites.

Drug concentration-dependent DNA lesions are induced by the lipid-soluble antifolate, piritrexim (BW301U).

The lipid-soluble folate antagonist, 2,4-diamino-6-(2,5-dimethoxybenzyl)-5-methylpyrido[2,3-d]pyrimidin e (piritrexim; BW301U), induced misincorporation of dUMP in human B (SB)- and T (MOLT-4)-lymphoblastoid cells, and in human promyelocytic leukemia cells (HL-60). Analysis by alkaline sucrose gradients and alkaline elution indicated that 3H-DNA that had been labeled for 15 min distributed into progressively smaller DNA fragment sizes in a drug concentration-dependent manner from 0 microM to 50 microM piritrexim. This phenomenon was observed regardless of the labeled nucleotide precursor employed for detection of newly synthesized DNA [( 3H]deoxyuridine, [3H]deoxyadenosine, or [3H]deoxycytidine). In contrast, formaldehyde denaturation and sedimentation of DNA in neutral denaturing sucrose gradients released only 3-4% of the newly synthesized DNA as 3S-6S fragments (80-200 nucleotides), whereas the remaining population of newly synthesized DNA pelleted to the bottom of the tube. Failure to detect DNA fragmentation under neutral conditions to the extent observed under alkaline conditions indicated the presence of apurinic and apyrimidinic sites in DNA--lesions which would be expected in DNA undergoing excision-repair of misincorporated dUMP. Cytotoxicity resulting from dUMP misincorporation was consistent with the enhanced toxicity of piritrexim which was observed when HL-60 cells or MOLT-4 cells were exposed concurrently to exogenous deoxyuridine. Deoxyuridine-enhanced toxicity was demonstrated to be concentration dependent for both cell lines when piritrexim concentrations were marginally toxic. The cytotoxic effect of dUMP misincorporation was further substantiated by the observation that MOLT-4 cells treated with 0.5 microM piritrexim alone eventually developed resistance to the drug, whereas treatment with both piritrexim and 10 microM deoxyuridine prevented the selection of piritrexim-resistant cells.