p53 gene status as a predictor of tumor response to induction chemotherapy of patients with locoregionally advanced squamous cell carcinomas of the head and neck

High-risk TP53 mutations predict poor primary treatment response of patients with head and neck squamous cell carcinoma

OBJECTIVES

Head and neck squamous cell carcinoma (HNSCC) poses a diagnostic and therapeutic challenge worldwide and is associated with a poor survival rate. Due to the variability in the efficacy of treatments for HNSCC, new predictive biomarkers of therapy outcomes are needed. Recently, we developed an algorithm that employs the mutational profile of TP53 as an independent prognostic factor in HNSCC. In this study, we investigated its role as a predictive biomarker of treatment outcomes in HNSCC patients. We also tested the usefulness of two classification systems for TP53 mutational landscapes.

MATERIALS AND METHODS

Clinical and genomic data were retrieved from The Cancer Genome Atlas database. We built a multivariate stepwise backward binary regression model to assess the role of TP53 mutations in predicting therapeutic outcomes.

RESULTS

Cases harbouring high-risk-of-death mutations reported an odds ratio of 3.301 for stable or progressive disease compared to wild-type cases, while no significant difference in treatment outcomes was found between cases with low-risk-of-death mutations and wild-type TP53. Our analysis found that older patients with a history of alcohol consumption had a higher risk of stable/progressive disease.

CONCLUSIONS

This study improves current evidence on the role of TP53 mutations in treatment response in HNSCC patients.

Induction chemotherapy in locally advanced head and neck cancers, is there a best choice?

Locally advanced stages of squamous cancers of the head and neck (LAHNCs) acquire high propensity for local and systemic relapse. Addition of systemic therapy as an induction (IC) to the standard concurrent chemoradiotherapy (CCRT) has become an approach of many practitioners. This strategy has shown to reduce metastases but did not affect survival in unselected populations. Meanwhile, the induction regimen including docetaxel, cisplatin, 5-FU (TPF) has shown superiority over other combinations, however, a survival advantage was not detected when compared to CCRT alone. This may be attributed to its high toxicity profile, inducing treatment delay, resistance, or variations in tumor sites and responses. Currently, newer systemic therapy combinations are being tested and indicators of benefit are being identified. The focus of this review is on the development of the choice of combination regimen for induction. Subsequently, proposed alternatives and strategies for patient selection will be introduced.

Mitotic Checkpoints and the Role of WEE1 Inhibition in Head and Neck Squamous Cell Carcinoma

ABSTRACT

The WEE1 kinase family plays a crucial role in cell cycle regulation and DNA damage response pathways in malignant cells. Inhibition of WEE1 effectively overrides G2 cell cycle arrest and results in the accumulation of extensive DNA damage within dividing cells, potentiating mitotic catastrophe and cell death. As such, the development of WEE1 inhibitors as antineoplastic therapeutics has gained increasing interest in recent years. In particular, the role of WEE1 inhibitors for treatment of head and neck squamous cell carcinomas remains an area of active research with both preclinical and clinical studies investigating their use as both single-agent therapy and chemosensitizers when used in tandem with traditional chemotherapy, particularly in the context of TP53-mutant tumors. Here, we review the relevant available preclinical and clinical data on hand investigating the efficacy of WEE1 inhibitors for the treatment of head and neck cancers.

Single-Cell Transcriptome Analysis Reveals Changes of Tumor Immune Microenvironment in Oral Squamous Cell Carcinoma After Chemotherapy

Induction chemotherapy in oral squamous cell carcinoma is a controversial issue in clinical practice. To investigate the evolution of cancer cells and tumor microenvironment (TME) response to chemotherapy in oral squamous cell carcinoma, single-cell transcriptome analysis was performed in a post-chemotherapy squamous cell carcinoma located in oral cavity. The main cell types were identified based on gene expression patterns determined using dimensionality reduction and unsupervised cell clustering. Non-negative matrix factorization clustering of the gene expression of Cancer-associated fibroblasts (CAFs) and macrophages was performed. Kyoto Encyclopedia of Genes and Genomes pathway analyses and gene set enrichment analysis were performed to explore significant functional pathways. CellPhoneDB and NicheNet were used to detect the intercellular communication between cell types. CAFs were divided into “inflammatory CAFs,” “antigen-presenting CAFs” and “myofibroblastic CAFs.” Three classic subgroups of tumor-associated macrophages (TAMs) were detected, namely C1Q (+), FCN1 (+) and SPP1(+) TAMs. The inflammatory cytokine expression is elevated, and several molecular pathways, such as PI3K/Akt/mTORC1, TNF-α via NFκB, TGF-β, IL-6/JAK2/STAT3 and CXCL12/CXCR4 axis associated with epithelial-mesenchymal transition were enriched in TME. Also, CD74-MIF/COPA/APP interactions were expressed in TME of oral squamous cell carcinoma after chemotherapy. The results revealed the characteristics of TME in post-chemotherapy oral squamous cell carcinoma at single-cell transcriptome level, providing new insights and clues for further investigation.

Evolutionary Action Score of TP53 Analysis in Pathologically High-Risk Human Papillomavirus-Negative Head and Neck Cancer From a Phase 2 Clinical Trial: NRG Oncology Radiation Therapy Oncology Group 0234

Purpose

An evolutionary action scoring algorithm (EAp53) based on phylogenetic sequence variations stratifies patients with head and neck squamous cell carcinoma (HNSCC) bearing TP53 missense mutations as high-risk, associated with poor outcomes, or low-risk, with similar outcomes as TP53 wild-type, and has been validated as a reliable prognostic marker. We performed this study to further validate prior findings demonstrating that EAp53 is a prognostic marker for patients with locally advanced HNSCC and explored its predictive value for treatment outcomes to adjuvant bio-chemoradiotherapy.

Methods and Materials

Eighty-one resection samples from patients treated surgically for stage III or IV human papillomavirus-negative HNSCC with high-risk pathologic features, who received either radiation therapy + cetuximab + cisplatin (cisplatin) or radiation therapy + cetuximab + docetaxel (docetaxel) as adjuvant treatment in a phase 2 study were subjected to TP53 targeted sequencing and EAp53 scoring to correlate with clinical outcomes. Due to the limited sample size, patients were combined into 2 EAp53 groups: (1) wild-type or low-risk; and (2) high-risk or other.

Results

At a median follow-up of 9.8 years, there was a significant interaction between EAp53 group and treatment for overall survival (P = .008), disease-free survival (P = .05), and distant metastasis (DM; P = .004). In wild-type or low-risk group, the docetaxel arm showed significantly better overall survival (hazard ratio [HR] 0.11, [0.03-0.36]), disease-free survival (HR 0.24, [0.09-0.61]), and less DM (HR 0.04, [0.01-0.31]) than the cisplatin arm. In high-risk or other group, differences between treatments were not statistically significant.

Conclusions

The docetaxel arm was associated with better survival than the cisplatin arm for patients with wild-type or low-risk EAp53. These benefits appear to be largely driven by a reduction in DM.

Pharmacologic inhibition of ataxia telangiectasia and Rad3-related (ATR) in the treatment of head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) poses significant treatment challenges, with high recurrence rates for locally advanced disease despite aggressive therapy typically involving a combination of surgery, radiation therapy, and/or chemotherapy. HNSCCs commonly exhibit reduced or absent TP53 function due to genomic alterations or human papillomavirus (HPV) infection, leading to dependence on the S- and G2/M checkpoints for cell cycle regulation. Both of these checkpoints are activated by Ataxia Telangiectasia and Rad3-related (ATR), which tends to be overexpressed in HNSCC relative to adjacent normal tissues and represents a potentially promising therapeutic target, particularly in combination with other treatments. ATR is a DNA damage signaling kinase that is activated in response to replication stress and single-stranded DNA breaks, such as those induced by radiation therapy and certain chemotherapies. ATR kinase inhibitors are currently being investigated in several clinical trials as part of the management of locally advanced, recurrent, or metastatic HNSCC, along with other malignancies. In this review article, we summarize the rationale and preclinical data supporting incorporation of ATR inhibition into therapeutic regimens for HNSCC.

The Molecular Basis and Therapeutic Aspects of Cisplatin Resistance in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is a kind of malignant tumors with low survival rate and prone to have early metastasis and recurrence. Cisplatin is an alkylating agent which induces DNA damage through the formation of cisplatin-DNA adducts, leading to cell cycle arrest and apoptosis. In the management of advanced OSCC, cisplatin-based chemotherapy or chemoradiotherapy has been considered as the first-line treatment. Unfortunately, only a portion of OSCC patients can benefit from cisplatin treatment, both inherent resistance and acquired resistance greatly limit the efficacy of cisplatin and even cause treatment failure. Herein, this review outline the underlying mechanisms of cisplatin resistance in OSCC from the aspects of DNA damage and repair, epigenetic regulation, transport processes, programmed cell death and tumor microenvironment. In addition, this review summarizes the strategies applicable to overcome cisplatin resistance, which can provide new ideas to improve the clinical therapeutic outcome of OSCC.

Somatic mutations in oral squamous cell carcinomas in 98 Japanese patients and their clinical implications

INTRODUCTION

The somatic mutational profile of oral squamous cell carcinoma (OSCC) among Japanese patients has been less investigated, partly because of the rarity of the tumor. Moreover, previous studies have either used formalin-fixed paraffin-embedded samples or lacked paired normal tissues. We aimed to determine somatic mutations in the exomes of 76 genes, including 50 driver genes of solid cancers and NOTCH-related genes, some of which are previously reported as frequently mutated in head and neck squamous cell carcinoma or OSCC.

MATERIALS AND METHODS

We used fresh-frozen tumor/normal-paired samples from 98 treatment-naïve Japanese patients with OSCC and analyzed their correlations with clinicopathological characteristics and survival.

RESULTS

We identified 136 exonic mutations, including 78 non-synonymous mutations, 13 synonymous mutations, 22 nonsense mutations, 2 non-frameshift deletions, 11 frameshift deletion, and 5 each of splice-site and frameshift insertions. The most frequently mutated genes were TP53 (36.7%), FAT1 (9.2%), NOTCH1 (8.2%), CDKN2A (7.1%), ZFHX4 (5.1%), CASP8 (4.1%), EP300 (4.1%), and KMT2D (4.1%). We followed up 90 of the 98 patients for 3 years. Among them, TP53 mutation was associated with significantly shorter 3-year disease-free survival. Most of the identified TP53 mutations occurred in the DNA-binding domain and were functionally deleterious.

DISCUSSION

Our findings and the mutation spectra can contribute to the development of a therapeutic strategy for Japanese patients with OSCC.

The oncogenicity of tumor-derived mutant p53 is enhanced by the recruitment of PLK3

p53 mutations with single amino acid changes in cancer often lead to dominant oncogenic changes. Here, we have developed a mouse model of gain-of-function (GOF) p53-driven lung cancer utilizing conditionally active LSL p53-R172H and LSL K-Ras-G12D knock-in alleles that can be activated by Cre in lung club cells. Mutation of the p53 transactivation domain (TAD) (p53-L25Q/W26S/R172H) eliminating significant transactivation activity resulted in loss of tumorigenicity, demonstrating that transactivation mediated by or dependent on TAD is required for oncogenicity by GOF p53. GOF p53 TAD mutations significantly reduce phosphorylation of nearby p53 serine 20 (S20), which is a target for PLK3 phosphorylation. Knocking out PLK3 attenuated S20 phosphorylation along with transactivation and oncogenicity by GOF p53, indicating that GOF p53 exploits PLK3 to trigger its transactivation capability and exert oncogenic functions. Our data show a mechanistic involvement of PLK3 in mutant p53 pathway of oncogenesis.

The mechanisms of how gain-of-function (GOF) mutant p53 drives carcinogenesis are unclear. Here, the authors show that a GOF mutant p53 requires its transactivation capability to induce mouse lung tumors and this is dependent on PLK3 phosphorylation of GOF mutant p53.

Clinico-pathological peculiarities of human papilloma virus driven head and neck squamous cell carcinoma: A comprehensive update

AIMS

The current article provides a detailed account of the current understanding of molecular and clinico-pathological aspects of Human papilloma virus (HPV) driven head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

The literature review included most of the landmark trials and clinical studies related to the HPV driven HNSCC.

KEY FINDINGS

HPV positive HNSCC differ distinctly from HPV negative tobacco-related HNSCC, especially in oropharyngeal region. Therefore, the American joint committee on cancer`s latest manual for classification and staging of cancer suggests a separate staging system for HPV positive oropharyngeal cancers. Despite the younger patients being affected and the high propensity for cervical metastasis, the HPV positive oropharyngeal cancers respond much better to the treatment. The association with wild type TP53 and low EGFR expression confers the favorable prognosis in HPV driven HNSCC. Since the association is not universal, we suggest checking for p53 and EGFR expression status before considering de-intensification of therapy. In addition, the presence of matted lymph nodes and five or more nodes could mean relatively poorer prognosis, and are not suitable for de-intensification of therapy. The same is also true probably with higher T stage and co-existing tobacco use. The methods for the detection of p16, HPV DNA, HPV E6/E7 mRNA, anti-E6/E7 antibodies, in tissue, in serum and in saliva of patients, along with their clinical implications are also discussed.

SIGNIFICANCE

This article provides latest developments on the HPV driven HNSCC. 'Diagnosis of transcriptionally active HPV infection,' 'Modalities for surveillance,' 'Implication of de-escalation of therapy' are some of the critical issues that could serve the medical, the research as well as the patient communities.

P53 Alteration in Oral Tongue Cancer is Not Significantly Associated with Age at Diagnosis or Tobacco Exposure

Aims and background

The tumor suppressor gene P53 is mutated in almost half of head and neck cancers. The current work assessed the prognostic significance of P53 alteration in patients with squamous cell carcinoma of the oral tongue treated with a curative intent, its association with age at diagnosis (using 45 years as a cut point), and risk exposure as defined by tobacco and/or alcohol consumption.

Methods

P53 alteration was determined immunohistochemically in 45 patients with tongue cancer treated with a curative intent.

Results

P53 alteration occurred in 20 of 45 tumors (44%) and was more common among younger patients (58% versus 36% for younger versus older patients, respectively) and those lacking tobacco/alcohol exposure (53% versus 40% for “no-risk” and “risk” groups, respectively), but the differences were not statistically significant. With a median follow-up of 56 months, 5-year progression-free survival rates were 48% and 66% in patients with and without P53 detection, respectively (P = 0.22).

Conclusions

Despite a trend of a younger age at diagnosis in P53-altered tumors, results did not reach statistically significant differences. A trend of a worse clinical outcome with P53 alteration was noted.

IRTKS is correlated with progression and survival time of patients with gastric cancer

BACKGROUND AND OBJECTIVES

IRTKS functions as a novel regulator of tumour suppressor p53; however, the role of IRTKS in pathogenesis of gastric cancer is unclear.

DESIGN

We used immunohistochemistry to detect IRTKS levels in 527 human gastric cancer specimens. We generated both IRTKS-deficient and p53-deficient mice to observe survival time of these mice and to isolate mouse embryonic fibroblasts (MEFs) for evaluating in vivo tumorigenicity. Co-immunoprecipitation was used to study the interaction among p53, MDM2 and IRTKS, as well as the ubiquitination of p53.

RESULTS

IRTKS was significantly overexpressed in human gastric cancer, which was conversely associated with wild-type p53 expression. Among patients with wild-type p53 (n=206), those with high IRTKS expression (n=141) had a shorter survival time than those with low IRTKS (n=65) (p=0.0153). Heterozygous p53^+/- mice with IRTKS deficiency exhibited significantly delayed tumorigenesis and an extended tumour-free survival time. p53^+/- MEFs without IRTKS exhibited attenuated in vivo tumorigenicity. IRTKS depletion upregulated p53 and its target genes, such as BAX and p21. Intriguingly, IRTKS overexpression promoted p53 ubiquitination and degradation in MEFs and gastric cancer cells. Under DNA damage conditions, IRTKS was phosphorylated at Ser331 by the activated Chk2 kinase and then dissociated from p53, along with the p53-specific E3 ubiquitin ligase MDM2, resulting in attenuated p53 ubiquitination and degradation.

CONCLUSION

IRTKS overexpression is negatively correlated with progression and overall survival time of patients with gastric cancer with wild-type p53 through promotion of p53 degradation via the ubiquitin/proteasome pathway.

p16 as a prognostic factor for the response to induction chemotherapy in advanced hypopharyngeal squamous cell carcinoma

The present study was conducted to investigate the prognostic significance of p16 (also known as cyclin-dependent kinase inhibitor 2A) in the treatment of induction chemoradiotherapy for advanced hypopharyngeal squamous cell carcinoma (HPSCC). Patients who were treated with at least two cycles of induction chemotherapy followed by concurrent chemoradiotherapy for locally advanced HPSCC were reviewed in the study. The staining results were analyzed to examine the association between the chemotherapy response and the survival outcome. A total of 45 patients were enrolled for the present study; the majority had received induction chemotherapy with docetaxel, cisplatin, and 5-FU. Following induction chemotherapy, 17 patients (37.8%) exhibited a complete response and 28 patients (62.2%) exhibited a partial response. There were 11 patients (24.4%) with p16-positive immunohistochemical stains and 30 patients (66.7%) with p53-positive immunohistochemical stains. There was no significant difference in chemotherapy response, overall survival, or progression-free survival time between groups with p16-positive and p16-negative stains. Low p53 expression and chemotherapy response were not associated with each other. High p16 expression did not correlate with low p53 expression. In this study, p16 was not determined to predict the chemotherapy response for HPSCC. High p16 expression did not correlate with survival incidence for patients with HPSCC.

Long-Term Results of Conventional Radiotherapy versus Accelerated Hyperfractionated Radiotherapy versus Concomitant Radiotherapy and Chemotherapy in Locoregionally Advanced Carcinoma of the Oropharynx

AIMS AND BACKGROUND

To compare conventional fractionation (CF) radiation therapy (RT), arm A, versus a split-course accelerated hyperfractionated schedule (S-AHF), arm B, versus CFRT plus concomitant chemotherapy (CT), arm C, in terms of five-year survival and toxicity for squamous cell tumors of the oropharynx.

METHODS AND STUDY DESIGN

Between January 1993 and June 1998, 192 previously untreated patients with stage III and IV oropharyngeal carcinoma (excluding T1N1 and T2N1) were enrolled in a multicenter randomized phase III trial (ORO 93-01). In arms A and C, 66 to 70 Gy in 33 to 35 fractions was administered five days a week for six and a half to seven weeks. In arm B, the dose delivered was 64 to 67.2 Gy in two fractions of 1.6 Gy every day, five days a week, with a planned two-week split at 38.4 Gy. In arm C the CT regimen consisted of three cycles of carboplatin and 5-fluorouracil (CBDCA 75 mg/m2 on days 1 to 4 and 5-FU 1000 mg/m2 i.v. on days 1 to 4 every 28 days).

RESULTS

No statistically significant difference was found in five-year overall survival (P = 0.39): 21% for arm A, 21% for arm B, and 40% for arm C. Similarly, there was no statistically significant difference in terms of five-year relapse-free survival: 15% for arm A, 17% for arm B, and 36% for arm C. There was a slight trend towards better five-year locoregional control (P = 0.07) for the combined arm: patients without locoregional relapse were 48% in arm C, 21% in arm A and 18% in arm B. Locoregional control was significantly better when arm C was compared with arms A and B combined (P = 0.02; arm A+B 20%; arm C 48%). Distant metastases were fairly balanced in the three arms (A: 14; B: 9; C: 11), with a tendency towards more frequent isolated distant metastasis development in arm C (8 of 11 [72%] versus 7 of 23 [30%] in arms A+B). Five-year second-tumor-free survival was 85%. The 13 second tumors were equally distributed and were mainly correlated with tobacco and alcohol consumption (five lung, two esophagus, two oral cavity, one larynx, one pancreas, one hepatocarcinoma, one myeloma). Arm C showed slightly more G3+ late side effects involving subcutaneous tissues and mucosa, although significant late sequelae were relatively uncommon and the mucosal side effects were mostly transient. The occurrence of persistent G3 xerostomia was comparable in the three treatment arms.

CONCLUSIONS

The results obtained with the combination of CT and RT compared with RT alone did not reach statistical significance, but combined treatment almost doubled the five-year overall survival, relapse-free survival and locoregional control rate. Patients with advanced squamous cell carcinomas of the oropharynx who are medically suitable for the combined approach should be treated with a combination of radiotherapy and chemotherapy. The occurrence of second tumors is relatively common in these patients and may contribute substantially to the causes of death.

p16 as a prognostic factor for the response to induction chemotherapy in advanced hypopharyngeal squamous cell carcinoma

The present study was conducted to investigate the prognostic significance of p16 (also known as cyclin-dependent kinase inhibitor 2A) in the treatment of induction chemoradiotherapy for advanced hypopharyngeal squamous cell carcinoma (HPSCC). Patients who were treated with at least two cycles of induction chemotherapy followed by concurrent chemoradiotherapy for locally advanced HPSCC were reviewed in the study. The staining results were analyzed to examine the association between the chemotherapy response and the survival outcome. A total of 45 patients were enrolled for the present study; the majority had received induction chemotherapy with docetaxel, cisplatin, and 5-FU. Following induction chemotherapy, 17 patients (37.8%) exhibited a complete response and 28 patients (62.2%) exhibited a partial response. There were 11 patients (24.4%) with p16-positive immunohistochemical stains and 30 patients (66.7%) with p53-positive immunohistochemical stains. There was no significant difference in chemotherapy response, overall survival, or progression-free survival time between groups with p16-positive and p16-negative stains. Low p53 expression and chemotherapy response were not associated with each other. High p16 expression did not correlate with low p53 expression. In this study, p16 was not determined to predict the chemotherapy response for HPSCC. High p16 expression did not correlate with survival incidence for patients with HPSCC.

P53 Gene Mutations in Surgical Margins and Primary Tumor Tissues of Patients with Squamous Cell Carcinoma of the Head and Neck

Aims and Background

The frequency of p53 mutations in primary tumors, the effect of the mutations on some clinical and pathological features of head and neck squamous cell carcinoma, and the impact of p53 mutations in the surgical margins on local recurrence were determined.

Material and Methods

We investigated the presence of p53 mutations in primary tumor samples and in the surgical margins of 34 patients with head and neck cancer using single strand conformational polymorphism and sequencing analysis.

Results

The p53 mutations (codons 175addAT, 175delGC, 206G→A, and 248delC) were found in the primary tumor samples of 15 of 34 patients (44.12%) and in the surgical margins of 5 of the 15 tumors (33.33%) with p53 mutations.

Conclusions

We found no statistically significant association between the presence of p53 mutations in the primary tumor, the clinical and pathological features, or outcome of head and neck squamous cell carcinoma in this study. Furthermore, the presence of p53 mutations in the surgical margins may not increase the risk of local-regional recurrence, but probably increases the risk of developing distant metastases or second primary tumors.

Current understanding of the tumor microenvironment of laryngeal dysplasia and progression to invasive cancer

PURPOSE OF REVIEW

This review examines the historical tumor progression genetic model of laryngeal carcinomas, from dysplasia to invasive carcinoma and the role of infiltrating immune and inflammatory cells as contributors to this process.

RECENT FINDINGS

Classically, the genetic model of carcinogenesis describes overexpression of oncogenes and/or silencing of tumor suppressor genes which, when combined with exposure to environmental carcinogens over the course of time, results in damage to cellular DNA. Increasing evidence indicates that innate and adaptive immune mediators also play an important role in tumor progression of laryngeal carcinomas. Cellular mediators of immune suppression are often over represented in the tumor microenvironment and these cells release cytokines, which perpetuate immune suppression allowing for tumor immune evasion.

SUMMARY

Future therapies targeting laryngeal malignancies should focus on a combined approach which targets both genetic variations and immune mediators.

Immunohistochemical correlates of TP53 somatic mutations in cancer

Despite controversy on the correlation between p53 accumulation and TP53 mutational status, immunohistochemical (IHC) detection of overexpressed protein has long been used as a surrogate method for mutation analysis. The aim of our study was to characterise the IHC expression features of TP53 somatic mutations and define their occurrence in human cancers. A large-scale database analysis was conducted in the IARC TP53 Database (R17); 7878 mutations with IHC features were retrieved representing 60 distinct tumour sites. The majority of the alterations were immunopositive (p <0.001). Sex was known for 4897 mutations showing a female dominance (57.2%) and females carrying negative mutations were significantly younger. TP53 mutations were divided into three IHC groups according to mutation frequency and IHC positivity. Each group had female dominance. Among the IHC groups, significant correlations were observed with age at diagnosis in breast, bladder, liver, haematopoietic system and head & neck cancers. An increased likelihood of false negative IHC associated with rare nonsense mutations was observed in certain tumour sites. Our study demonstrates that p53 immunopositivity largely correlates with TP53 mutational status but expression is absent in certain mutation types.Besides, describing the complex IHC expression of TP53 somatic mutations, our results reveal some caveats for the diagnostic practice.

Classification of TP53 mutations and HPV predict survival in advanced larynx cancer

OBJECTIVES/HYPOTHESIS

Assess tumor suppressor p53 (TP53) functional mutations in the context of other biomarkers in advanced larynx cancer.

STUDY DESIGN

Prospective analysis of pretreatment tumor TP53, human papillomavirus (HPV), Bcl-xL, and cyclin D1 status in stage III and IV larynx cancer patients in a clinical trial.

METHODS

TP53 exons 4 through 9 from 58 tumors were sequenced. Mutations were grouped using three classifications based on their expected function. Each functional group was analyzed for response to induction chemotherapy, time to surgery, survival, HPV status, p16INK4a, Bcl-xl, and cyclin D1 expression.

RESULTS

TP53 mutations were found in 22 of 58 (37.9%) patients with advanced larynx cancer, including missense mutations in 13 of 58 (22.4%) patients, nonsense mutations in four of 58 (6.9%), and deletions in five of 58 (8.6%). High-risk HPV was found in 20 of 52 (38.5%) tumors. A classification based on Evolutionary Action score of p53 (EAp53) distinguished missense mutations with high risk for decreased survival from low-risk mutations (P = 0.0315). A model including this TP53 classification, HPV status, cyclin D1, and Bcl-xL staining significantly predicts survival (P = 0.0017).

CONCLUSION

EAp53 functional classification of TP53 mutants and biomarkers predict survival in advanced larynx cancer.

LEVEL OF EVIDENCE

NA. Laryngoscope, 126:E292-E299, 2016.

Impact of EGFR and p53 expressions on survival and quality of life in locally advanced oral squamous cell carcinoma patients treated with chemoradiation

EGFR and p53 are molecular markers which play important role in tumor progression and development. The objective of this study was to assess the association between EGFR and p53 expression and survival, and to determine whether EGFR and p53 expression levels were associated with differences quality of life in OSCC patients undergoing chemoradiation. A total of 120 OSCC patients aged 20-67 y and stage III/IV were recruited. Treatment response was assessed according to W.H.O. (1979). EGFR and p53 expression in tumor tissue was estimated by immunohistochemical (IHC) method and quantified as percentage positive nuclei. Molecular marker expressions of both EGFR and p53 were found significantly (P < 0.01 or P < 0.001) associated with overall response, survivals and quality of life. Neither EGFR nor p53 expression was associated with hematologic or non-hematologic toxicity. EGFR and p53 molecular marker expressions may have significant association with survival and QOL in OSCC patients undergoing chemoradiation.

PITX1 is a novel predictor of the response to chemotherapy in head and neck squamous cell carcinoma

The pituitary homeobox 1 (PITX1) protein is essential for developmental processes in humans. Previously, PITX1 was identified as a possible tumor suppressor gene in various types of human carcinoma. However, the association between PITX1 and human head and neck squamous cell carcinoma (HNSCC) remains to be elucidated. Immunohistochemical analysis was performed to examine the expression levels of PITX1 in 47 cases of HNSCC, and in 4 control cases. The expression of p53 was also examined in these cases. The labeling indices (LIs) were calculated, and the correlations between clinical factors (chemosensitivity, prognosis and the degree of differentiation) and the LIs were assessed. The PITX1 LI in HNSCC was 27.4±14.5%, which was significantly lower compared with the LIs of the control samples: 76.9±6.97% (P<0.05). Additionally, the PITX1 LIs were 39.9±6.2, 26.9±16.9 and 24.2±11.8% in the complete response (CR), partial response (PR), stable disease or progressive disease (SD/PD) groups, respectively. The PITX1 LI in the CR group revealed the highest result between the all groups, and it was significantly greater compared with that in the SD/PD group (P<0.01). The p53 LIs were 24.5±19.9, 25.7±16.9 and 19.8±13.8 in the CR, PR and SD/PD groups, respectively (P>0.05). Neither the PITX1 nor the p53 LIs were a statistically significant indicator of the prognosis. PITX1 is a candidate tumor suppressor gene and a possible predictive biomarker of chemosensitivity of human HNSCC.

Biomarkers predicting chemotherapy response in head and neck squamous cell carcinoma: a review

BACKGROUND

Biomarkers are increasingly being used in many cancers to select patients for oncological treatment paradigms based on their inherent genetic properties. However, in head and neck cancers, there are no personalised therapies available outside the context of a clinical trial. A number of studies suggest there are intrinsic tumour properties of head and neck cancers that affect their response to chemotherapeutic agents. This paper aimed to review their evidence base.

METHOD

A narrative review was conducted following a search of the PubMed database.

RESULTS AND CONCLUSION

The review identified a number of biomarkers predicting response to chemotherapy in head and neck cancers. The paper discusses these in detail, and explores where future research could be directed in order to deliver personalised therapies for patients with head and neck cancers.

Wee-1 kinase inhibition overcomes cisplatin resistance associated with high-risk TP53 mutations in head and neck cancer through mitotic arrest followed by senescence

Although cisplatin has played a role in "standard-of-care" multimodality therapy for patients with advanced squamous cell carcinoma of the head and neck (HNSCC), the rate of treatment failure remains particularly high for patients receiving cisplatin whose tumors have mutations in the TP53 gene. We found that cisplatin treatment of HNSCC cells with mutant TP53 leads to arrest of cells in the G2 phase of the cell cycle, leading us to hypothesize that the wee-1 kinase inhibitor MK-1775 would abrogate the cisplatin-induced G2 block and thereby sensitize isogenic HNSCC cells with mutant TP53 or lacking p53 expression to cisplatin. We tested this hypothesis using clonogenic survival assays, flow cytometry, and in vivo tumor growth delay experiments with an orthotopic nude mouse model of oral tongue cancer. We also used a novel TP53 mutation classification scheme to identify which TP53 mutations are associated with limited tumor responses to cisplatin treatment. Clonogenic survival analyses indicate that nanomolar concentration of MK-1775 sensitizes HNSCC cells with high-risk mutant p53 to cisplatin. Consistent with its ability to chemosensitize, MK-1775 abrogated the cisplatin-induced G2 block in p53-defective cells leading to mitotic arrest associated with a senescence-like phenotype. Furthermore, MK-1775 enhanced the efficacy of cisplatin in vivo in tumors harboring TP53 mutations. These results indicate that HNSCC cells expressing high-risk p53 mutations are significantly sensitized to cisplatin therapy by the selective wee-1 kinase inhibitor, supporting the clinical evaluation of MK-1775 in combination with cisplatin for the treatment of patients with TP53 mutant HNSCC.

Different protein expression associated with chemotherapy response in oropharyngeal cancer according to HPV status

BACKGOUND

Oropharyngeal cancer (OPC) associated with human papilloma virus (HPV OPC) shows better treatment outcomes than non-HPV OPC. We investigated the expression of p53, β-tubulin, bcl-2 and ERCC 1, which are well-known biomarkers to predict the chemotherapy response, according to HPV status in OPC patients.

METHODS

Patients who treated with at least 2 cycles of induction chemotherapy followed by concurrent chemoradiotherapy for locally advanced oropharyngeal cancer were reviewed. HPV PCR and immunohistochemical stain was done in paraffin embedded tumor tissue and evaluated the relation with the chemotherapy response and survival outcomes according to HPV status.

RESULTS

Seventy-four patients were enrolled for this study and all patients received induction chemotherapy with docetaxel, 5-FU and cisplatin. After induction chemotherapy, complete response (CR) was shown in 22 patients (30%) and partial response (PR) in 46 patients (62%). HPV + was detected in 21 patients (28%), while 35 patients (47%) showed p16+ expression by IHC analysis. p16 positive patients showed better overall response, PFS and OS than p16 negative patients. p53 and class III beta-tubulin expression were significantly higher in HPV- and p16- than HPV + and p16+ patients. Conversely, bcl-2 expression was greater in HPV + or p16+ than HPV- or p16- patients. ERCC1 expression did not differ significantly according to HPV status. In multivariate analyses, early T stage (p = 0.036) and good PS (PS 0) (p = 0.029) showed a better 3Y-PFS rate, and low p53 expression (p = 0.012) and complete response after induction chemotherapy (p = 0.026) were highly associated with 3Y-OS rate. Low expression of p53 and p16 positive patients showed significantly prolonged OS than others (p = 0.010).

CONCLUSION

P53, class III beta-tubulin and bcl-2 were differently expressed in OPC according to HPV status and present study suggested the underlying mechanism of better response to chemotherapy in case of HPV OPC than non-HPV OPC. Among these biomarkers, p53 is the strongest prognostic marker in OPC and p53 in addition to p16 support the rationale to study of de-escalation strategy for OPC.

Beyond BRAF(V600): clinical mutation panel testing by next-generation sequencing in advanced melanoma

The management of melanoma has evolved due to improved understanding of its molecular drivers. To augment the current understanding of the prevalence, patterns, and associations of mutations in this disease, the results of clinical testing of 699 advanced melanoma patients using a pan-cancer next generation sequencing (NGS) panel of hotspot regions in 46 genes were reviewed. Mutations were identified in 43 of the 46 genes on the panel. The most common mutations were BRAF^V600 (36%), NRAS (21%), TP53 (16%), BRAF^Non-V600 (6%), and KIT (4%). Approximately one-third of melanomas had >1 mutation detected, and the number of mutations per tumor was associated with melanoma subtype. Concurrent TP53 mutations were the most frequent event in tumors with BRAF^V600 and NRAS mutations. Melanomas with BRAF^Non-V600 mutations frequently harbored concurrent NRAS mutations (18%), which were rare in tumors with BRAF^V600 mutations (1.6%). The prevalence of BRAF^V600 and KIT mutations were significantly associated with melanoma subtypes, and BRAF^V600 and TP53 mutations were significantly associated with cutaneous primary tumor location. Multiple potential therapeutic targets were identified in metastatic unknown primary and cutaneous melanomas that lacked BRAF^V600 and NRAS mutations. These results enrich our understanding of the patterns and clinical associations of oncogenic mutations in melanoma.

The mutational spectrum of squamous-cell carcinoma of the head and neck: targetable genetic events and clinical impact

Squamous-cell cancer of the head and neck (SCCHN) represents a heterogeneous disease entity, with various etiological factors implicated in the genesis of distinct molecular subsets of tumors, which exhibit different biological and clinical behavior. Treatment of SCCHN is expected to change in the next decade as targeted therapies continue to make strides. Recently, next-generation sequencing studies conducted on ∼190 SCCHN specimens shed light into the molecular pathogenesis of the disease. These studies discovered mutations in genes involved in the differentiation program of squamous epithelium and the Notch/p63 axis (such as NOTCH1, TP63 and FBXW7), and validated genetic alterations derived from previous studies (such as mutations in TP53, CDKN2A, PIK3CA, CCND1 and HRAS) as driver genetic events in SCCHN neoplastic transformation. More recently, comprehensive data from The Cancer Genome Atlas (TCGA) project on 306 SCCHN specimens provided further insight into SCCHN inherent molecular complexity, identifying novel significantly mutated genes, including FAT1, MLL2, TGFRBR2, HLA-A, NFE2l2 and CASP8. In this article, we provide an overview of the mutational spectrum of SCCHN, with emphasis on the clinical implementation of this knowledge. We also discuss the potential integration of new data within the framework of precision cancer medicine.

Comprehensive assessment of prognostic markers for sinonasal squamous cell carcinoma

BACKGROUND

Little is known about the molecular signature of the rare tumor sinonasal squamous cell carcinoma (SNSCC). The purpose of this study was to comprehensively assess various molecular biomarkers in SNSCC.

METHODS

We chose 13 markers for this study, which have been known as prognostic markers in head and neck squamous cell carcinoma. Expression of these markers was examined by either in situ hybridization or immunohistochemical methods on tissue microarrays made from 70 SNSCC specimens and 28 matched-pair normal tissues from patients who underwent surgical resection at our institution. Expression data were correlated with patient clinicopathologic parameters and survival.

RESULTS

Of the 13 markers, only epidermal growth factor receptor (EGFR) protein expression was associated with significantly shorter disease-free survival (DFS; p = .01307). EGFR expression was also associated with shorter overall survival (OS), but the difference was not statistically significant.

CONCLUSION

Targeted inhibition of tumor EGFR expression may be a new approach to treating SNSCC.

Differentiation of irradiation and cetuximab induced skin reactions in patients with locally advanced head and neck cancer undergoing radioimmunotherapy: the HICARE protocol (head and neck cancer: immunochemo and radiotherapy with erbitux) - a multicenter phase IV trial

Background

In order to improve the clinical outcome of patients with locally advanced squamous cell carcinoma of the head and neck (LASCCHN) not being capable to receive platinum-based chemoradiation, radiotherapy can be intensified by addition of cetuximab, a monoclonal antibody that blocks the epidermal growth factor receptor (EGFR). The radioimmunotherapy with cetuximab is a feasible treatment option showing a favourable toxicity profile. The most frequent side effect of radiotherapy is radiation dermatitis, the most common side effect of treatment with cetuximab is acneiform rash. Incidence and severity of these frequent, often overlapping and sometimes limiting skin reactions, however, are not well explored. A clinical and molecular differentiation between radiogenic skin reactions and skin reactions caused by cetuximab which may correlate with outcome, have never been described before.

Methods/design

The HICARE study is a national, multicenter, prospective phase IV study exploring the different types of skin reactions that occur in patients with LASCCHN undergoing radioimmun(chemo)therapy with the EGFR inhibitor cetuximab. 500 patients with LASCCHN will be enrolled in 40 participating sites in Germany. Primary endpoint is the rate of radiation dermatitis NCI CTCAE grade 3 and 4 (v. 4.02). Radioimmunotherapy will be applied according to SmPC, i.e. cetuximab will be administered as loading dose and then weekly during the radiotherapy. Irradiation will be applied as intensity-modulated radiation therapy (IMRT) or 3D-dimensional radiation therapy.

Discussion

The HICARE trial is expected to be one of the largest trials ever conducted in head and neck cancer patients. The goal of the HICARE trial is to differentiate skin reactions caused by radiation from those caused by the monoclonal antibody cetuximab, to evaluate the incidence and severity of these skin reactions and to correlate them with outcome parameters. Besides, the translational research program will help to identify and confirm novel peripheral blood based molecular predictors and surrogates for treatment response and resistance.

Trial registration

Clinical Trial Identifier, NCT01553032 (clinicaltrials.gov)

EudraCT number: 2010-019748-38

Chk1/2 inhibition overcomes the cisplatin resistance of head and neck cancer cells secondary to the loss of functional p53

Despite the use of multimodality therapy using cisplatin to treat patients with advanced stage squamous cell carcinoma of the head and neck (HNSCC), there is an unacceptably high rate of treatment failure. TP53 is the most commonly mutated gene in HNSCC, and the impact of p53 mutation on response to cisplatin treatment is poorly understood. Here, we show unambiguously that wild-type TP53 (wtp53) is associated with sensitivity of HNSCC cells to cisplatin treatment, whereas mutation or loss of TP53 is associated with cisplatin resistance. We also show that senescence is the major cellular response to cisplatin in wtp53 HNSCC cells and that cisplatin resistance in p53-null or -mutant TP53 cells is due to their lack of senescence. Given the dependence on checkpoint kinase (Chk)1/2 kinases to mediate the DNA damage response in p53-deficient cells, there is potential to exploit this to therapeutic advantage through targeted inhibition of the Chk1/2 kinases. Treatment of p53-deficient HNSCC cells with the Chk inhibitor AZD7762 sensitizes them to cisplatin through induction of mitotic cell death. This is the first report showing the ability of a Chk kinase inhibitor to sensitize TP53-deficient HNSCC to cisplatin in a synthetic lethal manner, which has significance given the frequency of TP53 mutations in this disease and because cisplatin has become part of standard therapy for aggressive HNSCC tumors. These preclinical data provide evidence that a personalized approach to the treatment of HNSCC based on Chk inhibition in p53-mutant tumors may be feasible.

Oral cavity and oropharyngeal squamous cell carcinoma genomics

Recent technological advances now permit the study of the entire cancer genome, which can elucidate complex pathway interactions that are not apparent at the level of single genes. In this review, the authors describe innovations that have allowed for whole-exome/genome analysis of genetic and epigenetic alterations and of changes in gene expression. Studies using next-generation sequencing, array comparative genomic hybridization, methylation arrays, and gene expression profiling are reviewed, with a particular focus on findings from recent whole-exome sequencing projects. A discussion of the implications of these data on treatment and future goals for cancer genomics is included.

Interactions between the tumor suppressor p53 and immune responses

PURPOSE OF REVIEW

The p53 tumor suppressor is a master regulator of antitumor defenses through its control of growth arrest, senescence and apoptosis. In recent years, p53 regulation was found to extend to a variety of biological processes including autophagy, fertility, metabolism and immune responses. Here, we focus on the role of p53 in the immune system. We explore the relationship between p53 and the innate immune response with particular emphasis on the Toll-like receptor (TLR) pathway and implications for cancer therapy.

RECENT FINDINGS

Numerous studies have shown that the immune system, especially innate immunity, has a critical role in tumor development. It appears that p53 can influence innate immune responses as part of its tumor suppressor activities and recent work suggests that the complete set of innate immune TLR genes are responsive to chromosomal stress and the transcriptional network regulated by p53. Activation of p53 by common antitumor agents results in p53 dependent regulation of expression of most TLR genes in human primary and cancer cell lines, resulting in modulation of TLR downstream responses to cognate ligands. In addition several tumor-associated p53 mutants can also affect TLR gene expression. These observations together with the discovery of other immune-related p53 target genes provide new insights into the relationship between p53 and immunity and suggest approaches that might be useful in cancer therapies.

SUMMARY

The tumor suppressor p53 can modulate innate immune gene responses in response to factors that can activate p53. This is expected to provide new opportunities in cancer diagnosis and in chemotherapeutic strategies that employ specific TLR agonists or antagonists that target the TLR pathway.

Elevated cyclin D1 expression is predictive for a benefit from TPF induction chemotherapy in oral squamous cell carcinoma patients with advanced nodal disease

Induction chemotherapy is likely to be effective for biologically distinct subgroups of patients with cancer with biomarker detection. To investigate the prognostic and predictive values of cyclin D1 expression in patients with oral squamous cell carcinoma (OSCC) who were treated in a prospective, randomized, phase III trial evaluating standard treatment with surgery and postoperative radiotherapy preceded or not by induction docetaxel, cisplatin, and 5-fluorouracil (TPF), immunohistochemical staining for cyclin D1 was conducted in pretreatment biopsy specimens of 232 out of 256 clinical stage III/IVA OSCC patients randomized to the clinical trial. Cyclin D1 index was estimated as the proportion of tumor cells with cyclin D1 nuclear staining. A low cyclin D1 expression predicted significantly better overall survival (OS; P = 0.001), disease-free survival (P = 0.005), locoregional recurrence-free survival (P = 0.003), and distant metastasis-free survival (DMFS; P = 0.002) compared with high cyclin D1 expression. Cyclin D1 expression levels were not predictive of benefit from induction TPF in the population overall. However, patients with nodal stage cN2 whose tumors had high cyclin D1 expression treated with TPF had significantly greater OS (P = 0.025) and DMFS (P = 0.025) when compared with high cyclin D1 cN2 patients treated with surgery upfront. Patients with low cyclin D1 level or patients with cN0 or cN1 disease did not benefit from induction chemotherapy. This study indicates that cN2 OSCC patients with high cyclin D1 expression can benefit from the addition of TPF induction chemotherapy to standard treatment. Cyclin D1 expression could be used as a biomarker in further validation studies to select cN2 patients that could benefit from induction therapy.

Induction chemotherapy in patients with resectable head and neck squamous cell carcinoma: a meta-analysis

Background

Induction chemotherapy has been investigated as a possible strategy to shrink or downstage locally advanced head and neck cancers, providing opportunity to remove the lesions completely after induction chemotherapy, especially in the patients with resectable advanced disease. The aim of this study was to investigate the definitive effect of induction chemotherapy in patients with resectable head and neck squamous cell carcinoma.

Methods

A meta-analysis of randomized trials (1965–2011) was performed on the impact of induction chemotherapy on survival, disease control, and toxicity in this population of patients. Kaplan-Meier curves were read by Engauge-Digitizer. Data combining was performed using RevMan.

Results

Fourteen trials (2099 patients) were involved in this analysis. There was no significant difference on overall survival, disease free survival, or locoregional recurrence between the patients treated with and without induction chemotherapy (P >0.05). However, the patients treated with induction chemotherapy had a lower rate of distant metastasis by 8% (95% confidence interval 1%–16%, P = 0.02) than those treated without induction chemotherapy. In patients with laryngeal cancer, comparing to radical surgery, the larynx could be preserved in responders to induction chemotherapy without survival decease (P >0.05). Induction chemotherapy-associated death was 0%–5%.

Conclusions

Based on the results above, there is a significant benefit of induction chemotherapy on decreasing distant metastasis in patients with resectable head and neck squamous cell carcinoma. In patients with laryngeal cancer, induction chemotherapy provides larynx preservation in responders to induction chemotherapy.

Randomized phase III trial of induction chemotherapy with docetaxel, cisplatin, and fluorouracil followed by surgery versus up-front surgery in locally advanced resectable oral squamous cell carcinoma

PURPOSE

To evaluate induction chemotherapy with docetaxel, cisplatin, and fluorouracil (TPF) followed by surgery and postoperative radiotherapy versus up-front surgery and postoperative radiotherapy in patients with locally advanced resectable oral squamous cell carcinoma (OSCC).

PATIENTS AND METHODS

A prospective open-label phase III trial was conducted. Eligibility criteria included untreated stage III or IVA locally advanced resectable OSCC. Patients received two cycles of TPF induction chemotherapy (docetaxel 75 mg/m(2) on day 1, cisplatin 75 mg/m(2) on day 1, and fluorouracil 750 mg/m(2) on days 1 to 5) followed by radical surgery and postoperative radiotherapy (54 to 66 Gy) versus up-front radical surgery and postoperative radiotherapy. The primary end point was overall survival (OS). Secondary end points included local control and safety.

RESULTS

Of the 256 patients enrolled onto this trial, 222 completed the full treatment protocol. There were no unexpected toxicities, and induction chemotherapy did not increase perioperative morbidity. The clinical response rate to induction chemotherapy was 80.6%. After a median follow-up of 30 months, there was no significant difference in OS (hazard ratio [HR], 0.977; 95% CI, 0.634 to 1.507; P = .918) or disease-free survival (HR, 0.974; 95% CI, 0.654 to 1.45; P = .897) between patients treated with and without TPF induction. Patients in the induction chemotherapy arm with a clinical response or favorable pathologic response (≤ 10% viable tumor cells) had superior OS and locoregional and distant control.

CONCLUSION

Our study failed to demonstrate that TPF induction chemotherapy improves survival compared with up-front surgery in patients with resectable stage III or IVA OSCC.

Tp53 status as guide for the management of ethmoid sinus intestinal-type adenocarcinoma

OBJECTIVE

Intestinal-type adenocarcinoma (ITAC) of the ethmoid sinus is a rare, occupational-related tumor. Optimal treatment consists of surgery and radiotherapy, while chemotherapy is still investigational. The molecular profile of ITAC is characterized by the occurrence of TP53 mutations associated with genotoxic agents such as wood dust. We investigated the role of p53 functionality in relation to the primary treatment.

MATERIALS AND METHODS

We retrospectively reviewed 100 medical charts of consecutive patients with a first diagnosis of ITAC treated at our Institute; 74 patients were evaluable for TP53 analysis. Thirty (41%) were treated from 1991 to 2006 with craniofacial resection followed by radiotherapy (Group A), compared with 44 patients (59%) treated from 1996 to 2006 with cisplatin-based induction chemotherapy (PFL) followed by standard treatment (Group B).

RESULTS

Five-year OS in Group A was 42%, while in Group B it was 70% (p = 0.041); 5-year DFS in Group A was 40%, while in Group B it was 66%, (p = 0.009) (p = 0.061 and 0.003 at Cox multivariable OS and DFS analyses). Analyzing each group according to p53 functional status, only for Group B patients (who received preoperative chemotherapy) both OS and DFS were in favor of functional p53 (p = 0.023 and p = 0.010, respectively). No impact of p53 functional status as a biomarker was observed in Group A.

CONCLUSIONS

Functional p53 may predict PFL-chemotherapy efficacy, offering a possible increase in survival when induction chemotherapy is given to a selected population. On the other hand, upcoming innovative approaches should be explored in the presence of non-functional p53.

Lessons learned from next-generation sequencing in head and neck cancer

Scientific innovation has enabled whole exome capture and massively parallel sequencing of cancer genomes. In head and neck cancer, next-generation sequencing has granted us further understanding of the mutational spectrum of squamous cell carcinoma. As a result of these new technologies, frequently occurring mutations were identified in NOTCH1, a gene that had not previously been implicated in head and neck cancer. The current review describes the most common mutations in head and neck cancer: TP53, NOTCH1, HRAS, PIK3CA, and CDKN2A. Emphasis is placed on the involved cellular pathways, clinical correlations, and potential therapeutic interventions. Additionally, the implications of human papillomavirus on mutation patterns are discussed.

Induction chemotherapy decreases the rate of distant metastasis in patients with head and neck squamous cell carcinoma but does not improve survival or locoregional control: a meta-analysis

The definitive effect of induction chemotherapy (IC) on locally advanced head and neck squamous cell carcinoma (HNSCC) remains uncertain and although randomized controlled trials are supposed to provide high levels evidence for clinical guidelines, the data thus far has been conflicted. In an effort to elucidate the potential benefit of IC, a meta-analysis of randomized controlled trials (1965-2011) was performed investigating the impact of IC on survival, locoregional control, distant metastasis, and toxicity in HNSCC. Kaplan-Meier curves were read by a digitizing software-Engauge Digitizer. Data combination was performed using the software-RevMan and trial level log hazard ratio (HR) and variance were pooled and presented. Among the 40 eligible trials, 28 trials encompassing 4189 patients receiving locoregional treatment with or without IC were included in the analysis. The cumulative benefit of IC on overall survival and distant metastasis was 6% (HR = 0.94, 95%CI = 0.87-1.01, P = 0.11) and 7% (95%CI = 0-13%, P = 0.05) respectively while for locoregional control a benefit was not observed as seen by the -2% (95%CI = -11% to 8%, P = 0.73) improved control rate. In a subsite analysis specifically for laryngeal preservation, IC did not significantly improve survival (P = 0.47). There was a significant benefit from the cisplatin and 5-fluorouracil (PF) protocols with an increase in overall survival of 13% (HR = 0.87, 95%CI = 0.78-0.97, P = 0.01), and a reduction in the 5-year distant metastasis rate of 11% (95%CI = 0-21%, P = 0.04). The occurrence of grade 3/4 mucositis, leukopenia and emesis was significantly lower in patients receiving IC compared to patients receiving concomitant chemoradiotherapy. In conclusion, there is not a significant benefit of the pooled IC regimens in HNSCC on survival or locoregional control. In contrast, IC does show significant benefit in the reduction of distant metastasis. When protocols using a PF regimen are analyzed independently, a significant improvement in survival and rate of distant metastases is observed while there is not a benefit in locoregional control. The routine use of IC is still debatable. IC could be applied on larynx preservation strategy.

The human TLR innate immune gene family is differentially influenced by DNA stress and p53 status in cancer cells

The transcription factor p53 regulates genes associated with a wide range of functions, including the Toll-like receptor (TLR) set of innate immunity genes, suggesting that p53 also modulates the human immune response. The TLR family comprises membrane glycoproteins that recognize pathogen-associated molecular patterns (PAMP) and mediate innate immune responses, and TLR agonists are being used as adjuvants in cancer treatments. Here, we show that doxorubicin, 5-fluorouracil, and UV and ionizing radiation elicit changes in TLR expression that are cell line- and damage-specific. Specifically, treatment-induced expression changes led to increased downstream cytokine expression in response to ligand stimulation. The effect of DNA stressors on TLR expression was mainly mediated by p53, and several p53 cancer-associated mutants dramatically altered the pattern of TLR gene expression. In all cell lines tested, TLR3 induction was p53-dependent, whereas induction of TLR9, the most stress-responsive family member, was less dependent on status of p53. In addition, each of the 10 members of the innate immune TLR gene family tested was differentially inducible. Our findings therefore show that the matrix of p53 status, chromosome stress, and responsiveness of individual TLRs should be considered in TLR-based cancer therapies.

Disruptive TP53 mutation is associated with aggressive disease characteristics in an orthotopic murine model of oral tongue cancer

PURPOSE

To characterize tumor growth and metastatic potential in head and neck squamous cell carcinoma (HNSCC) cell lines in an orthotopic murine model of oral tongue cancer and to correlate TP53 mutation status with these findings.

EXPERIMENTAL DESIGN

Cells from each of 48 HNSCC cell lines were orthotopically injected into the oral tongues of nude mice. Tumor volume, cervical lymph node metastasis, and mouse survival were recorded. Direct sequencing of the TP53 gene and Western blot analysis for the p53 protein after induction with 5-fluorouracil was conducted. Cell lines were categorized as either mutant TP53 or wild-type TP53, and lines with TP53 mutation were further categorized on the basis of type of mutation (disruptive or nondisruptive) and level of p53 protein expression. The behavior of tumors in these different groups was compared.

RESULTS

These 48 HNSCC cell lines showed a wide range of behavior from highly aggressive and metastatic to no tumor formation. Mice injected with cells harboring disruptive TP53 mutations had faster tumor growth, greater incidence of cervical lymph node metastasis, and shorter survival than mice injected with cells lacking these mutations.

CONCLUSIONS

HNSCC cell lines display a wide spectrum of behavior in an orthotopic model of oral cancer. Cell lines with disruptive TP53 mutations are more aggressive in this system, corroborating clinical reports that have linked these mutations to poor patient outcome.

Novel biomarker panel predicts prognosis in human papillomavirus-negative oropharyngeal cancer: an analysis of the TAX 324 trial

BACKGROUND

New treatment strategies for locally advanced head and neck squamous cell carcinoma combine induction chemotherapy and chemoradiation. Identifying the predictors of outcome in sequentially treated patients is critical for focusing therapeutic research. In this analysis, the authors evaluated human papillomavirus type 16 (HPV-16) status and the expression levels of a defined set of biomarkers to identify predictors of response to this treatment modality.

METHODS

In total, 114 patients with oropharyngeal cancer (OPC) who were treated on the TAX 324 trial (cisplatin and fluorouracil with or without docetaxel in patients with locally advanced head and neck squamous cell carcinoma) had pretreatment biopsy specimens that were evaluable for HPV-16 DNA and immunohistochemical expression of the following biomarkers: beta-tubulin II (βT-II), glutathione S-transferase (GST-π), p53, and B-cell lymphoma 2 (Bcl-2). Patients were categorized into risk groups based on their HPV status and biomarker expression levels.

RESULTS

Patients with high-risk OPC were defined by HPV-negative status and either elevated expression of βT-II or levels of at least 2 of the other 3 adverse markers (elevated GST-π, elevated p53, or low Bcl-2). All other HPV-negative patients were categorized as moderate risk. In total, 55 patients were HPV-positive, and 59 patients were HPV-negative, with 34 were categorized as high risk and 25 categorized as moderate risk. The median survival for HPV-positive patients was not reached. The median survival was 44.2 months for moderate-risk patients (95% confidence interval, 20.9 months to not reached) and 12.1 months for high-risk patients (95% confidence interval, 7.5-19.7 months). The 24-month survival rate was 89% for HPV-positive patients, 67% for moderate-risk patients, and 29% for high-risk patients (P < .0001).

CONCLUSIONS

The molecular data set in this study readily differentiated between 2 distinct groups of patients with locally advanced, HPV-negative OPC. This risk-stratification strategy may serve as a guide for treatment selection.

Oncogenomic Approaches in Exploring Gain of Function of Mutant p53

Cancer is caused by the spatial and temporal accumulation of alterations in the genome of a given cell. This leads to the deregulation of key signalling pathways that play a pivotal role in the control of cell proliferation and cell fate. The p53 tumor suppressor gene is the most frequent target in genetic alterations in human cancers. The primary selective advantage of such mutations is the elimination of cellular wild type p53 activity. In addition, many evidences in vitro and in vivo have demonstrated that at least certain mutant forms of p53 may possess a gain of function, whereby they contribute positively to cancer progression. The fine mapping and deciphering of specific cancer phenotypes is taking advantage of molecular-profiling studies based on genome-wide approaches. Currently, high-throughput methods such as array-based comparative genomic hybridization (CGH array), single nucleotide polymorphism array (SNP array), expression arrays and ChIP-on-chip arrays are available to study mutant p53-associated alterations in human cancers. Here we will mainly focus on the integration of the results raised through oncogenomic platforms that aim to shed light on the molecular mechanisms underlying mutant p53 gain of function activities and to provide useful information on the molecular stratification of tumor patients.

Genetics/epigenetics of oral premalignancy: current status and future research

Squamous cell carcinoma (SCC) of the oral and oropharyngeal region is the sixth most common malignancy in the world today. Despite numerous advances in treatment, long-term survival from this disease remains poor. Early detection can decrease both morbidity and mortality associated with this neoplasm. However, screening for potentially malignant disease is typically confounded by difficulty in discriminating between reactive/inflammatory lesions vs those lesions that are premalignant in nature. Furthermore, the histologic diagnosis of dysplasia can be subjective and is thus prone to a considerable range of interpretation. Similarly, no definitive, validated criteria exist for predicting which dysplastic lesions are most likely to progress to cancer over time. Given this state of science, the presence of dysplasia can only be used to indicate that an oral lesion may have an increased risk of malignant transformation. Molecular biomarkers capable of identifying the subset of lesions likely to progress to cancer are required to eliminate this clinical diagnostic dilemma. The purpose of this review is to assess the current state of knowledge regarding genetic/epigenetic alterations observed in oral mucosal premalignancy. In addition, recommendations for future research studies directed at defining the predictive capacity of specific biomarkers in this modeling are presented.