Genetic polymorphisms and head and neck cancer outcomes: a review

MYEOV with High Frequencies of Mutations in Head and Neck Cancers Facilitates Cancer Cell Malignant Behaviors

Cancer driver genes (CDGs) and the driver mutations disrupt the homeostasis of numerous critical cell activities, thereby playing a critical role in tumor initiation and progression. In this study, integrative bioinformatics analyses were performed based on a series of online databases, aiming to identify driver genes with high frequencies of mutations in head and neck cancers. Higher myeloma overexpressed (MYEOV) genetic variation frequency and expression level were connected to a poorer prognosis in head and neck cancer patients. MYEOV was dramatically upregulated within head and neck tumor samples and cells. Consistently, MYEOV overexpression remarkably enhanced the aggressiveness of head and neck cancer cells by promoting colony formation, cell invasion, and cell migration. Conversely, MYEOV knockdown attenuated cancer cell aggressiveness and inhibited tumor growth and metastasis in the oral orthotopic tumor model. In conclusion, MYEOV is overexpressed in head and neck cancer, with greater mutation frequencies correlating to a poorer prognosis in head and neck cancer patients. MYEOV serves as an oncogene in head and neck cancer through the promotion of tumor cell colony formation, invasion, and migration, as well as promoting tumor growth and metastasis in the oral orthotopic tumor model.

Association between XRCC1 Arg399Gln polymorphism with prognosis of head and neck squamous cell carcinomas: A meta-analysis

Objective

The X-ray repair cross complementing group 1 (XRCC1) gene is involved in DNA repair. Defects in DNA repair may lead to head and neck squamous cell carcinomas (HNSCCs). Several researches have focused on relationship between XRCC1 Arg399Gln genetic polymorphism with HNSCC's prognosis with conflicting results. So, the aim of the present meta-analysis was evaluation of relationship between XRCC1 Arg399Gln polymorphism with HNSCC's prognosis.

Methods

Published articles up to July 2022 were systematically searched through international databases like PubMed, Web of Science, Scopus, etc. I2 test was applied to assess the heterogeneity. Data were analyzed using random effects model. Funnel plots and Egger test were applied for assessing publication biases. The hazard ratios (HRs) and 95 % confidence intervals (CIs) were calculated for evaluation of relationship between the polymorphism with HNSCC's prognosis.

Results

Fifteen articles were included for the systematic review. Six of those articles were considered for inclusion in meta-analysis. The different forms of XRCC1 Arg399Gln polymorphism had not significant association with overall survival (OS) under varied genetic models (heterozygous: Ln (HR) = 0.02, 95 % CI= (-0.33,0.37), p-value = 0.90; homozygous: Ln (HR) = 0.33, 95 % CI= (-0.03,0.69), p-value = 0.07 and dominant: Ln (HR) = 0.06, 95 % CI = (-0.17,0.28), p-value = 0.62). Analysis showed that variants of the polymorphism had no significant relationship with OS in Asian and Caucasian ethnicity under dominant model (Ln (HR) = 0.14, 95 % CI= (-0.13,0.40), p-value = 0.31; Ln (HR) = -0.01, 95 % CI= (-0.41,0.38), p-value = 0.96).

Conclusion

Different forms of XRCC1 Arg399Gln polymorphism had no significant relationship with HNSCC's prognosis under varied genetic models and based on different ethnicity.

Dental considerations for head and neck cancer: A clinical review

Introduction

Radiotherapy is one of the treatment modalities for the treatment of head and neck cancer (HNC). However, it leads to the development of chronic and acute side effects. These side effects impact negatively on the patient's quality of life and oral functioning. This clinical review aims to provide basic information about HNC, understand the impact of radiotherapy on oral health, and explain the role of dental care providers for HNC patients during the pre-and post-radiotherapy time.

Materials and Methods

Electronic databases (i.e., PubMed, Scopus, and Google Scholar) were searched using defined keywords. The main inclusion criteria were any studies describing "dental management of patients with head and neck cancer" and "dental management of patients treated with radiotherapy."

Results

Thematic analysis was used to summaries the findings of the included studies (n = 102) into main headings and subheadings. All studies were published between 1970 and 2023.

Conclusion

The number of HNC patients is increasing. This necessitates the need for raising the awareness of dental care providers to the side-effects of HNC therapy which includes treatment with radiotherapy, chemotherapy, and/or surgery. Dental care providers should understand the common side-effects and their treatments besides their role in the pre- (i.e., dental extraction of teeth with poor prognosis and maintaining good oral hygiene) and post- (i.e., oral rehabilitation and post-HNC dental care) radiotherapy dental care.

Gene polymorphisms and prognosis of head and neck squamous cell carcinoma: a systematic review

Background

Head and neck squamous cell carcinomas (HNSCCs) are associated with variable prognosis even with similar clinical characteristics and treatments. Gene polymorphisms have been suggested as prognostic factors for HNSCC which can justified this variable prognosis. So, the aim was to review literatures on gene polymorphisms and prognosis of HNSCCs.

Materials and methods

A systematic search was conducted using PubMed, Web of science, SCOPUS, Google Scholar and Cochrane library databases to find all related articles published up to December 2021 in the field of gene polymorphisms and HNSCC prognosis.

Results

Of 1029 initial searched articles, 71 articles were selected for inclusion in this systematic review. About 93 genes and 204 polymorphisms have been discussed in these articles. Among the most studied polymorphisms, the XRCC1 Arg399Gln and Arg194Trp polymorphisms were not associated with survival in most studies; the ERCC1 C19007T polymorphism had no significant association in any of the studies. Different gene polymorphisms of glutathione s-transferase family, including GSTM1 deletion, GSTT1 deletion and GSTP1 A313G, were not associated with survival in included studies. There are conflicting results regarding the association between polymorphisms such as ERCC2 A35931C, Asp312Asn, ERCC5 rs1047768 and rs17655 with HNSCC prognosis. Less studied polymorphisms, such as hOGG1 rs1052133 or the VEGF rs699947, were generally not associated with HNSCC prognosis.

Conclusion

Reviewed articles reported varied and contradictory results regarding the association of gene polymorphisms and HNSCC prognosis, which necessitates further studies along with meta-analysis on the results of such studies.

Cytochrome P450 isoforms 1A1, 1B1 AND 2W1 as targets for therapeutic intervention in head and neck cancer

Epidemiological studies have shown that head and neck cancer (HNC) is a complex multistage process that in part involves exposure to a combination of carcinogens and the capacity of certain drug-metabolising enzymes including cytochrome P450 (CYP) to detoxify or activate such carcinogens. In this study, CYP1A1, CYP1B1 and CYP2W1 expression in HNC was correlated with potential as target for duocarmycin prodrug activation and selective therapy. In the HNC cell lines, elevated expression was shown at the gene level for CYP1A1 and CYP1B1 whereas CYP2W1 was hardly detected. However, CYP2W1 was expressed in FaDu and Detroit-562 xenografts and in a cohort of human HNC samples. Functional activity was measured in Fadu and Detroit-562 cells using P450-Glo™ assay. Antiproliferative results of duocarmycin prodrugs ICT2700 and ICT2706 revealed FaDu and Detroit-562 as the most sensitive HNC cell lines. Administration of ICT2700 in vivo using a single dose of ICT2700 (150 mg/kg) showed preferential inhibition of small tumour growth (mean size of 60 mm³) in mice bearing FaDu xenografts. Significantly, our findings suggest a potential targeted therapeutic approach to manage HNCs by exploiting intratumoural CYP expression for metabolic activation of duocarmycin-based prodrugs such as ICT2700.

The Association Between the XRCC1 Arg399Gln Polymorphism and the Risk of Head and Neck Cancer: An Updated Meta-Analysis Including 14586 Subjects

BACKGROUND

Accumulated evidence shows that DNA repair gene X-ray repair cross complementing group 1 (XRCC1) may determine individual susceptibility to head and neck cancer (HNC) as a major DNA repair gene. However, the results from previous studies have been conflictive and inconsistent. In order to more accurately estimate and integrate the association between XRCC1 Arg399Gln polymorphism and HNC risk, we conducted a meta-analysis including 14586 subjects.

METHODS

In this meta-analysis, literatures were collected up until September 15, 2020 through multifarious retrieval strategies by searching through electronic databases of PubMed, Cochrane Library, EMBASE, Medline, Web of Science and CNKI. The association between the XRCC1 Arg399Gln polymorphism and HNC was analyzed through calculating summary odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Thirty-one studies consisting of 6025 cases and 8561 controls were identified and analyzed. No significant association between XRCC1 Arg399Gln polymorphisms and HNC risk was found under the allelic (OR = 0.94, 95% CI: 0.82-1.07, P = 0.35), homozygous (OR = 0.99, 95% CI: 0.81-1.21, P = 0.91), heterozygous (OR = 1.01, 95% CI: 0.90-1.13, P = 0.91), dominant (OR = 1.05, 95% CI: 0.85-1.29, P = 0.67) or recessive (OR = 0.93, 95% CI: 0.80-1.08, P = 0.35) genetic models in the overall comparison. In addition, subgroup analyses according to tumor site also displayed no significant association between XRCC1 Arg399Gln polymorphisms and HNC risk. However, subgroup analyses based on ethnicity indicated that HNC risk was significantly related to Arg399Gln genetic heterozygous model (OR = 1.21, 95%CI: 1.04-1.42, P = 0.02) and dominant model (OR = 1.27, 95%CI: 1.02-1.60, P = 0.04) in Caucasians populations.

CONCLUSION

The results from this meta-analysis suggest that the XRCC1 Arg399Gln variants (Arg/Gln and Arg/Arg+Arg/Gln) may contribute to high HNC risk among Caucasians. Further well-designed studies and larger sample sizes are needed to validate our findings.

Single nucleotide polymorphisms and the risk of developing a second primary cancer among head and neck cancer patients: a systematic literature review and meta-analysis

BACKGROUND

Head and Neck Cancer (HNC) survivors are at increased risk of developing a second primary cancer (SPC). Along with the environmental risk factors, genetic factors have been associated with a potential increased susceptibility to SPC development. We aim to identify the Single Nucleotide Polymorphisms (SNPs) that contribute to SPC development among HNC survivors through a systematic review and meta-analysis.

METHODS

We searched PubMed, Scopus and ISI Web of Science for eligible studies published in English until January 31st, 2020. We included studies reporting primary data that evaluated the association between SNPs and SPC risk in HNC patients. Data were pooled in a random-effect meta-analyses, when at least two studies on the same SNP evaluated the same genotype model. Heterogeneity was assessed using the χ2-based Q-statistics and the I2 statistics. Quality of the included studies was assessed using the Q-Genie tool.

RESULTS

Twenty-one studies, of moderate to good quality, were included in the systematic review. Fifty-one genes were reported across the included studies to have significant associations with an increased SPC risk. Overall, 81 out of 122 investigated SNPs were significantly associated with the SPC risk. Seven studies were included in the meta-analysis, which showed five SNPs associated with an increased risk of SPC: p21C70T, CT + TT (HR = 1.76; 95% CI: 1.28-2.43); FASLG -844C > T, CT + TT (HR = 1.82; 95% CI: 1.35-2.46), P21 C98A, CA + AA (HR = 1.75; 95% CI: 1.28-2.38); FAS -670A > G (HR = 1.84; 95% CI: 1.28-2.66) and GST-M1, Null genotype (HR = 1.54; 95% CI: 1.13-2.10).

CONCLUSIONS

The identified SNPs in our systematic review and meta-analysis might serve as potential markers for identification of patients at high risk of developing SPC after primary HNC.

PROSPERO REGISTRATION NUMBER

CRD42019135612 .

Genetic Variants of DNA Repair Genes as Predictors of Radiation-Induced Subcutaneous Fibrosis in Oropharyngeal Carcinoma

Purpose

To investigate the impact of genetic variants of DNA repair and pro-fibrotic pathway genes on the severity of radiation-induced subcutaneous fibrosis in patients of oropharyngeal carcinoma treated with radical radiotherapy.

Materials and Methods

Patients of newly diagnosed squamous cell carcinoma of oropharynx being treated with two-dimensional radical radiotherapy were enrolled in the study. Patients who had undergone surgery or were receiving concurrent chemotherapy were excluded. Patients were followed up at 6 weeks post completion of radiotherapy and every 3 months thereafter for a median of 16 months. Subcutaneous fibrosis was graded according to the Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC) grading system and the maximum grade was recorded over the length of the patient’s follow-up. Patients with severe fibrosis (≥G3), were compared to patients with minor (≤G2) fibrotic reactions. Eight single nucleotide polymorphisms of 7 DNA repair genes and 2 polymorphisms of a single pro-fibrotic pathway gene were analyzed by Polymerase Chain Reaction and Restriction Fragment Length Polymorphism and were correlated with the severity of subcutaneous fibrosis.

Results

179 patients were included in the analysis. Subcutaneous fibrosis was seen in 168 (93.9%) patients. 36 (20.1%) patients had severe (grade 3) fibrosis. On multivariate logistic regression analysis, Homozygous CC genotype of XRCC3 (722C>T, rs861539) (p=0.013*, OR 2.350, 95% CI 1.089-5.382), Homozygous AA genotype of ERCC4 Ex8 (1244G>A, rs1800067) (p=0.001**, OR 11.626, 95% CI 2.490-275.901) and Homozygous TT genotype of XRCC5 (1401G>T, rs828907) (p=0.020*, OR 2.188, 95% CI 1.652-7.334) were found to be predictive of severe subcutaneous fibrosis. On haplotype analysis, the cumulative risk of developing severe fibrosis was observed in patients carrying both haplotypes of variant Homozygous AA genotype of ERCC4 Ex8 (1244G>A, rs1800067) and Homozygous TT genotype of XRCC5 (1401 G>T, rs828907) (p=0.010*, OR 26.340, 95% CI 4.014-76.568).

Conclusion

We demonstrated significant associations between single nucleotide polymorphisms of DNA repair genes and radiation-induced subcutaneous fibrosis in patients of oropharyngeal carcinoma treated with radiotherapy. We propose to incorporate these genetic markers into predictive models for identifying patients genetically predisposed to the development of radiation-induced fibrosis, thus guiding personalized treatment protocols.

Correlative analysis between cytotoxic T lymphocyte antigen 4 genetic polymorphisms and head and neck cancer susceptibility: A protocol for systematic review and meta-analysis

BACKGROUND

Previous published studies have reported the association of cytotoxic T lymphocyte antigen 4 (CTLA-4) genetic polymorphisms with the susceptibility to head and neck cancer, but the results remain controversial. We therefore will conduct a meta-analysis to investigate the relationship between CTLA-4 genetic polymorphisms and head and neck cancer susceptibility.

METHODS

We will systematically search case-control studies for potential eligible studies from Cochrane Library, EMBASE, Google Scholar, PubMed, China Biomedical Database, WanFang database, and China National Knowledge Infrastructure (CNKI). Additionally, we will also examine other sources to avoid missing potential trials. Two authors will independently collect and perform the study selection, data extraction, and study methodological quality. Statistical analyses were utilized using STATA 12.0 and RevMan 5.3, and the odds ratios (ORs) with 95% confidence intervals (95% CI) were used to estimate the strength of the association of CTLA-4 genetic polymorphisms with the susceptibility to head and neck cancer.

RESULTS

This protocol study will assess the relationship between CTLA-4 genetic polymorphisms and head and neck cancer susceptibility.

CONCLUSION

The findings of this study will provide systematic evidence for future guidance developing and clinical decision making in patients with head and neck cancer.

ETHICS AND DISSEMINATION

Ethical approval will not be required as this study is a systematic review.

PROTOCOL REGISTRATION NUMBER

DOI 10.17605/OSF.IO/BFJTZ (https://osf.io/bfjtz/).

Effects of the professional oral care management program on patients with head and neck cancer after radiotherapy: A 12-month follow-up

Background/purpose

Because oral health of patients with head & neck cancer is prone to disease after radiotherapy, effective and long-lasting oral care program is necessary. We aimed to evaluate the effects of the oral care management program, which lasted up to 12 months after radiotherapy for patients with head and neck cancer.

Materials and methods

Sixty-eight patients who visited a dental clinic prior to the initiation of radiotherapy were recruited and categorized into either a “healthy” or a “vulnerable” group. The vulnerable group was made of patients with dental caries or periodontal attachment loss. Professional oral hygiene care, including tooth brushing instructions, professional mechanical tooth cleaning, and fluoride varnish application, was conducted once every week for a month during radiotherapy and once every 3 months after radiotherapy. Oral health, including dental caries, plaques, gingival index, and periodontal attachment loss, was examined at baseline, 6 months, and 12 months after radiotherapy.

Results

; Twenty-nine and 16 patients were followed up at 6 and 12 months after radiotherapy, respectively. Oral health indices, such as the number of decayed teeth, amount of plaque, and gingival index, did not significantly change in either group. However, the periodontal pocket depth significantly decreased in both groups at 6 months after baseline, and this decrease continued in the vulnerable group up to 12 months after baseline.

Conclusion

Periodic dental visits and professional oral hygiene care during and after radiotherapy were effective in maintaining oral health for over 12 months after radiotherapy in patients with head and neck cancer.

Genotype of Null Polymorphisms in Genes GSTM1, GSTT1, CYP1A1, and CYP1A1*2A (rs4646903 T>C)/CYP1A1*2C (rs1048943 A>G) in Patients with Larynx Cancer in Southeast Spain

Simple Summary

Epidemiological studies have shown that individual susceptibility to cancer is mediated by genetic and environmental factors. The aim of the present study is to evaluate the individuals’ metabolic genetic susceptibility to toxic habits (smoking and alcohol consumption) by detecting polymorphisms CYP1A1 rs1048943 T>C and CYPA1A2 rs4646903 A>G, and null polymorphisms in GSTM1 and GSTT1 genotypes, comparing a group of healthy control subjects with a population of larynx cancer patients from southeastern Spain. As results patients with larynx cancer present more gene GSTM1 and GSTT1 null polymorphisms, and CYP1A1 rs4646903 T>C polymorphisms.

Abstract

Background: some types of cancer have been associated with the presence of single nucleotide polymorphisms (SNPs) of some genes that encode enzymes: glutathione-S transferase (GST), whose alteration leads to loss of function and a lower capacity to eliminate toxic GSTM1 and GSTT1 null genotypes; SNPs causing loss of function of CYP1A1 or CYP1A1–2 cytochrome P450 enzymes related with a lower capacity to deactivate hydrocarbons related to smoking, which involves a higher risk of developing some smoking-dependent cancers including larynx cancer. Objective: to compare the presence of null SNPs in genes GSTM1, GSTT1, and CYP1A1 rs 4646903 T>C, and CYP1A1–2 RS1048943 A>G in patients with hypopharyngeal and larynx cancer with a healthy control group. Materials and method: The study included a total of 80 patients with hypopharyngeal and laryngeal cancer and 23 healthy subjects. Genomic DNA was obtained from saliva samples, determining genotype GSTM1 (present +, or null −), GSTT1 (present + or null −). Polymorphisms (SNP) in CYP1A1 T>C (present + CC, or absent − TC/TT), and CYP1A1–2 A>G (present + GG, or absent − AG/AA). Results: the mean age of patients with larynx cancer was 62 years and of control subjects 63 years. Of the total sample, over 95% were men, and over 90% were smokers. The presence of null genotypes for GTM1 was 50% in patients with larynx cancer (p = 0.042), while GSTT1 was 88.75% (p = 0.002). CYP1A1 rs4646903 T>C polymorphisms were detected in 100% of cases of larynx cancer and 17.39% of healthy subjects (p > 0.001). Conclusions: patients with larynx cancer present more gene GSTM1 and GSTT1 null polymorphisms, and CYP1A1 rs4646903 T>C polymorphisms.

Vascular endothelial growth factor (VEGF) and Endocrine gland-VEGF (EG-VEGF) are down regulated in head and neck cancer

OBJECTIVE

To characterise the role of VEGF, EG-VEGF and its receptors in the development and progression of HNC.

DESIGN

Human serum and tissues samples were collected from healthy, epulis and HNC patients and used for ELISA assays and immunohistochemistry studies, respectively.

SETTING

Ibn Rochd Hospital of Casablanca (Morocco), INSERM and University of Grenoble Alpes (France).

PARTICIPANTS

We used serum from 64 patients with head and neck cancers and from 71 controls without general pathology. Tissues samples were collected from seven patients with OSCC and from seven patients with Epulis.

MAIN OUTCOME MEASURES

We compared circulating VEGF and EG-VEGF in normal and HNC patients and determined the expression, localisation and quantification of VEGF, EG-VEGF and its receptors; PROKR1 and PROKR2 as well as Ki67, CD31 and CD34 in OSCC and Epulis patients.

RESULTS

Both EG-VEGF and VEGF circulating levels were significantly decreased in the HNC (P < .01). OSCC patients expressed less EG-VEGF and VEGF proteins, higher PROKR1 and PROKR2 with no change in CD31 and CD34 levels. A significant increase in Ki67 was observed in OSCC.

CONCLUSIONS

We demonstrated that circulating VEGF and EG-VEGF are downregulated in HNC patients and in OSCC tissue. EG-VEGF receptors were increased in OSCC, along with a stabilisation of two key markers of angiogenesis. These findings strongly suggest that downregulation of angiogenesis in HNC might explain its moderate metastatic feature.

Unraveling cancer lineage drivers in squamous cell carcinomas

Cancer hijacks embryonic development and adult wound repair mechanisms to fuel malignancy. Cancer frequently originates from de-regulated adult stem cells or progenitors, which are otherwise essential units for postnatal tissue remodeling and repair. Cancer genomics studies have revealed convergence of multiple cancers across organ sites, including squamous cell carcinomas (SCCs), a common group of cancers arising from the head and neck, esophagus, lung, cervix and skin. In this review, we summarize our current knowledge on the molecular drivers of SCCs, including these five major organ sites. We especially focus our discussion on lineage dependent driver genes and pathways, in the context of squamous development and stratification. We then use skin as a model to discuss the notion of field cancerization during SCC carcinogenesis, and cancer as a wound that never heals. Finally, we turn to the idea of context dependency widely observed in cancer driver genes, and outline literature support and possible explanations for their lineage specific functions. Through these discussions, we aim to provide an up-to-date summary of molecular mechanisms driving tumor plasticity in squamous cancers. Such basic knowledge will be helpful to inform the clinics for better stratifying cancer patients, revealing novel drug targets and providing effective treatment options.

Biomarkers in Head and Neck Cancer an Update

The study is aimed at establishing the purpose of tumour markers, their application, classification, diagnostic and therapeutic roles in the management of head and neck cancer. A literature review using Medline, Scopus, Google Scholar, the Cochrane Database of Systematic Reviews and the Cochrane central register of controlled trials for articles published between 1993 and 2016 on tumour markers and their role in head and neck cancer was performed. A broader search of prognostic markers in head and neck cancer was also carried out to avoid missing other pertinent markers. Natural history, tumour biology, stage and prognostic factors influence the outcome of management in patients with Head and Neck Squamous cell carcinoma (HNSCC). Evaluation of the cellular lineage and histogenic origin of diverse neoplasms can be done using tumour biomarkers. Identifying predictive tumour markers can lead to improvement in preventive management of HNSCC. There has been remarkable advancement in molecular technology with gene expression and proteomic profiling. Integration of specific tumour markers into routine clinical practice requires substantiation through well designed clinical trials. The investigation of tumour markers is imperative as they influence the prognosis of HNSCC and provide the potential to improve outcomes of treatment through targeted therapy. We have outlined recent tumour biomarkers in this review which have significant role in diagnosis, screening and prognostication in HNSCC. Recent advancement in clinical applications, therapeutic strategies of tumour markers has been highlighted.

Comparison of hospital based and home based exercise on quality of life, and neck and shoulder function in patients with spinal accessary nerve injury after head and neck cancer surgery

OBJECTIVES

The purpose of this study was to compare the effects of hospital-based and home-based exercise programs on quality of life (QOL) and neck and shoulder function of patients who underwent head and neck cancer (HNC) surgery.

METHODS

This clinical trial included 40 patients with neck and shoulder dysfunction after HNC. The exercise program included range of motion (ROM) exercises, massage, stretching, and strengthening exercises. Twenty patients who were assigned to the hospital-based exercise group performed physical therapy for 40 min three times a week for four weeks, and the remaining 20 patients were assigned to the home-based group. The European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30), the EORTC Head and Neck Questionnaire (EORTC QLQ-H&N), the Neck and Shoulder Disability Index (NDI), ROM, and numeric rating scale (NRS) were assessed before and after the exercise program. The program consisted of a 10-minute ROM to the neck and shoulder, a 10-minute massage, and 15 min of progressive resistance exercises, followed by a five-minute stretching exercise.

RESULTS

There were statistically significant differences in the changes of neck and shoulder disability index (p < .05). Additionally, there were significant differences in neck extension and rotation ROM and NRS in the hospital-based group compared with the home-based group (p < .05). QOL was not significantly different between the two groups.

CONCLUSIONS

Home-based exercise was effective for improving QOL, shoulder function, and pain relief. Hospital-based exercise had better effects on physical function of the neck and shoulder and reduced pain.

Clinical and Molecular Characterization of Surgically Treated Oropharynx Squamous Cell Carcinoma Samples

A better understanding of the clinical and molecular features of oropharyngeal squamous cell carcinomas (OPSCC) may help in the development of strategies for a better patient management, improving survival rates. This retrospective study conducted a clinical and molecular characterization of surgically treated OPSCC samples. Paraffin-embedded samples from a series of cases were screened for high-risk (HR) human papillomavirus (HPV) infection, methylation of a 5-gene panel, p53 expression, and TP53 mutation. The study was conducted at Barretos Cancer Hospital. Twenty-five surgically treated OPSCC with available tissue were included in the study. Samples were classified according to HPV status and molecular features and some of these characteristics were associated to clinical data. Twenty percent of the cases were HR-HPV positive and 62.5% presented TP53 mutations. DAPK hypermethylation was associated with HPV status (p = 0.023), while methylated CCNA1 was inversely related to TP53 mutations in primary tumors (p = 0.042) and associated with a better disease-free survival (22.3% vs. 100.0%; p = 0.028) and overall survival (8.0% vs. 100.0%; p = 0.012). The results show differences regarding molecular and clinical characteristics in the oropharynx cases identified that should be validated in more cases to confirm whether these differences are able to classify patients according to outcome and help in a more thorough patient management.

No association of TNF-α-308G/A polymorphisms with head and neck cancer risk: A PRISMA-compliant meta-analysis

BACKGROUND

A number of studies had reported the association between tumor necrosis factor-alpha (TNF-α) gene polymorphisms and head and neck cancer (HNC) risk. However, the results remained controversial. Therefore, we performed a meta-analysis to derive a more precise evaluation of the association between TNF-α-308G/A polymorphism and overall HNC risk and evaluated influence of cancer types and ethnicities.

METHODS

A systematic literature search was performed using Pubmed, Embase, Cochrane Library, and Web of science. In total, we identified 15 studies including 2005 cancer cases and 2876 controls to evaluate the association of TNF-α-308G/A polymorphism with risk for HNC.

RESULTS

Overall, there was no significant association between TNF-α-308G/A polymorphism and the risk of HNC. Furthermore, subgroup analyses were performed according to the types of tumor and the ethnicities, we also found there was no significant association between TNF-α-308G/A polymorphism and the risk of NPC and OC, and European and Asian populations had no statistically significant difference in the relationship of TNF-α-308G/A polymorphism and HNC susceptibility.

CONCLUSION

This meta-analysis indicates that the TNF-α-308G/A polymorphism is not associated with HNC risk. In the future, large and well-designed case-control studies are needed to validate our findings.

A genome-wide association study of non-HPV-related head and neck squamous cell carcinoma identifies prognostic genetic sequence variants in the MAP-kinase and hormone pathways

BACKGROUND

Carcinomas of the oral cavity, pharynx and larynx are referred to as head and neck cancers (HNC); together they account for 2-3% of all newly diagnosed cancers in North America. Between 40-50% of HNC are early diagnosed at stages I-II. The 5-year and 10-year relative survival rates are 61% and 50%, respectively. Germline genetic sequence variants (GSV) have become increasingly found to have prognostic implications in a variety of cancers. Identifying these variants may have important clinical and biological implications.

METHODS

We conducted a genome-wide association study (GWAS) in 531 Stage I-II radiation-treated HNC patients (originally recruited for α-tocopherol/β-carotene placebo-controlled secondary prevention study) and used a replication cohort of 566 HNC patients of all stages, of mostly non-HPV-related cancers. Survival rates were estimated by the Kaplan-Meier method. Cox proportional hazards models adjusted for potential clinical factors and principal components were used to test for associations between the GSV and overall survival (OS) in these tumors.

RESULTS

The median follow-up time for OS was 9.21 years (GWAS cohort) and 2.37 years (replication cohort). In both cohorts, CACNA2D1:rs2299187, ESRRG:rs946465 and ESRRG:rs1416612 were each individually significantly associated with survival. In silico analysis of ESRRG:rs946465 identifies that it produces a splice variant in ESRRG. Variant alleles of CACNA2D1:rs2299187 and ESRRG:rs946465 were associated with higher expression of the corresponding protein.

CONCLUSIONS

Putatively functional polymorphisms in the MAP-Kinase and estrogen pathways, identified through GWAS and replicated in an independent dataset were associated with the survival of HNC patients.

Genetic Association between the XPG Asp1104His Polymorphism and Head and Neck Cancer Susceptibility: Evidence Based on a Meta-Analysis

BACKGROUND

Previous studies evaluating the association between the xeroderma pigmentosum group G (XPG) Asp1104His polymorphism and head and neck cancer susceptibility have proven controversial. This meta-analysis of the literature was performed to obtain a more precise estimation of the relationship.

MATERIALS AND METHODS

We systematically searched PubMed, Embase and Web of Science with a time limit of Dec 18, 2014. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of any association.

RESULTS

We performed a meta-analysis of eight published case-control studies, including 3,621 cases and 5,475 controls. Overall, no significant association was found between the XPG Asp1104His polymorphism and head and neck cancer susceptibility under all genetic models. In the subgroup analysis by ethnicity, the XPG Asp1104His polymorphism had statistically significant association with elevated head and neck cancer risk under CC vs GG (OR=1.24, 95% CI=1.00~1.54) and the recessive model (OR=1.22, 95%CI=1.01~1.46) in Asian populations. A similar result was found under CC vs GG (OR =1.22, 95%CI =1.01~1.47) in the population based subgroup by source of control. When performed by tumor site, the XPG Asp1104His polymorphism had statistically significant association with elevated laryngeal cancer under all genetic models (CC vs GG: OR=1.59, 95% CI=1.16~2.19; GC vs GG: OR=1.38, 95%CI=1.10~1.72; dominant model: OR=1.42, 95% CI=1.15~1.74; recessive model: OR=1.36, 95% CI=1.02~1.81).

CONCLUSIONS

This meta-analysis suggested that the XPG Asp1104His polymorphism is a risk factor for head and neck cancer susceptibility, especially for laryngeal cancer and in Asian populations.

Prognostic Value of Drinking Status and Aldehyde Dehydrogenase 2 Polymorphism in Patients With Head and Neck Squamous Cell Carcinoma

Background

The association between alcohol drinking, aldehyde dehydrogenase 2 (ALDH2) polymorphism, and survival in patients with head and neck squamous cell carcinoma (HNSCC) remains unclear.

Methods

We performed a retrospective cohort study of 267 HNSCC patients at Aichi Cancer Center. Of these, 65 patients (24%) were non-drinkers, 104 (39%) were light drinkers (ethanol <46 g or <5 days/week), 46 (17%) were moderate drinkers (ethanol intake 46–68 g/day and ≥5 days/week), and 52 (20%) were heavy drinkers (ethanol intake ≥69 g and ≥5 days/week). The prognostic value of pre-treatment drinking status and ALDH2 polymorphism was investigated using multivariate proportional hazard models.

Results

Drinking status was associated with disease-free survival (DFS) in HNSCC patients, with marginal statistical significance (5-year DFS: 67.9% [95% confidence interval {CI}, 53.8–78.4%] for non-drinkers, 57.6% [95% CI, 47.4–66.6%] for light drinkers, 46.1% [95% CI, 30.8–60.1%] for moderate drinkers, and 43.5% [95% CI, 29.3–56.9%] for heavy drinkers; P = 0.088). However, this association lost significance when multivariate analyses were adjusted for established prognostic factors. ALDH2 genotype was not significantly associated with DFS in HNSCC patients (5-year DFS: 85.7% [95% CI, 53.9–96.2%] for Lys/Lys, 56.2% [95% CI, 47.4–64.1%] for Glu/Lys, and 50.5% [95% CI, 40.3–59.7%] for Glu/Glu; P = 0.154). After stratification by ALDH2 genotype, we observed a significant positive dose-response relationship between drinking status and DFS in HNSCC patients with ALDH2 Glu/Glu (P_trend = 0.029).

Conclusions

In this study, we identified a significant positive dose-response relationship between pre-treatment drinking status and DFS in HNSCC patients with ALDH2 Glu/Glu. To confirm this association, further study is warranted.

Association of cyclin D1 variants with head and neck cancer susceptibility: evidence from a meta-analysis

Whether cyclin D1 (CCND1) gene variants increase susceptibility to head and neck cancer (HNC) is undetermined. Therefore, we performed the present meta-analysis to systematically assess any possible association between CCND1 variants (G870A and G1722C) and HNC risk. Seventeen studies for CCND1 G870A and three studies for CCND1 G1722C were included. Overall, CCND1 polymorphisms (G870A and G1722C) had no association with increased HNC risk (p>0.05). In the subgroup analysis by smoking status, significantly increased HNC risk was found among smokers under allele contrast, homozygous comparison and recessive models (p<0.05), smoking carriers of A allele and AA genotype appearing at elevated risk. In conclusion, while there was overall a lack of any association between CCND1 polymorphisms (G870A and G1722C) and HNC risk, smokers carrying the A allele and AA genotype of the CCND1 G870A polymorphism may be susceptible to HNC development.

PHF21B as a candidate tumor suppressor gene in head and neck squamous cell carcinomas

A significant association between DNA losses on 22q13.31 and head and neck squamous cell carcinomas (HNSCC) was previously reported by our group. Our data indicated that PHF21B gene, mapped on 22q13.31 and encoding a protein with function of chromatin-mediated transcriptional regulation, might be a putative tumor suppressor gene. To test this hypothesis, gene copy number was assessed in 75 HNSCC and 49 matched peripheral blood samples. PHF21B losses were detected in 43 tumors and were significantly associated with patients with familial history of cancer (P < 0.0001); i.e., 36/43 cases showed a positive family history of cancer and 22/36 had first-degree relatives with cancer (P = 0.049). In attempt to investigate other mechanisms for PHF21B loss of function, DNA sequencing was performed and no mutations were detected. We next evaluated the gene expression levels after inhibition of DNA methylation in nine HNSCC and breast carcinoma cell lines. Additionally, PHF21B expression levels were evaluated in colon cancer HCT116 cells as well as in its counterpart DKO (double knockout of DNMT1 and DNMT3B). The higher expression levels of PHF21B gene detected in DKO cells were inversely correlated with the DNA methylation. Further, DNA methylation in the specific promoter-associated CpG Island was investigated. Interestingly, gene hypermethylation was detected in 13/37 tumors: 5/13 HNSCC cases had family history of cancer in first-degree relatives and 8/13 showed both, DNA methylation and PHF21B losses in the tumor sample. One patient had PHF21B loss in the peripheral blood cells and PHF21B methylation in the tumor sample. Additionally, overexpression of PHF21B in cell lines drastically reduces clonogenic and migratory abilities. These data suggest that PHF21B is a novel tumor suppressor gene that can be inactivated by genetic and epigenetic mechanisms in the human cancer.

Association of XPD Lys751Gln polymorphism with head and neck cancer susceptibility: evidence from 11,443 subjects

BACKGROUND

Whether the single nucleotide polymorphism (SNP) Lys751Gln of xeroderma pigmentosum group D(XPD) gene increases susceptibility to head and neck cancer (HNC) is controversial and undetermined. Therefore, we conducted this meta-analysis to systematically assess the possible association between them.

METHODS

The OVID, Medline, Embase, Pubmed, Web of Science databases were searched to identify the eligible studies. The odds ratio (OR) with 95% confidence interval (95% CI) were used to assess the strength of association.

RESULTS

A total of 11,443 subjects from eighteen studies were subjected to meta-analysis. Overall, XPD Lys751Gln polymorphism had no association with increased HNC risk under all five genetic models (P > 0.05). In the subgroup analysis by ethnicity and source of controls, still no significant association was found under five genetic models (P > 0.05). In the subgroup analysis by cancer type, XPD Lys751Gln polymorphism had statistically significant association with elevated laryngeal cancer (LC) and nasopharyngeal cancer (NPC) risk under heterozygous comparison and dominant model (P<0.05) and borderline significantly increased risk was found under allele contrast for LC and NPC. Carriers of Lys allele and Lys/Lys genotype may be associated with elevated LC and NPC risk.

CONCLUSIONS

There is overall lack of association between XPD Lys751Gln polymorphism and HNC risk under all five genetic models and still no significant association was found in the subgroup analysis by ethnicity and source of controls. However, XPD Lys751Gln polymorphism was significantly associated with susceptibility to LC and NPC and the Lys allele and Lys/Lys genotype of XPD Lys751Gln polymorphism may be a risk factor for LC and NPC. However, relatively modest sample sizes were included in this meta-analysis and studies with large sample sizes and representative population are warranted to further clarify this finding.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5628716106316015.

Cyclin D1 G870A polymorphism and risk of nasopharyngeal carcinoma: a meta-analysis

Recently, there have been a number of studies on the association between cyclin D1 G870A polymorphism and nasopharyngeal carcinoma risk. However, the results of previous reports remain controversial and ambiguous. Thus, we performed a meta-analysis to explore more precisely the association between cyclin D1 G870A polymorphism and the risk of nasopharyngeal carcinoma. No significant association was found between cyclin D1 G870A polymorphism and nasopharyngeal carcinoma risk in total population analysis. In the subgroup meta-analysis by ethnicity, a negative association was shown in Caucasian subgroup, and no significant association in any genetic models among Asians was observed. In summary, positive results have been shown on the search for polymorphic variants influencing the risk of NPC. This meta-analysis provides evidence of the association between CCND1 G870A polymorphism and NPC risk, supporting the hypothesis that CCND1 870A allele probably acts as an important NPC protective factor in Caucasians but not in Asians. Since the results of our meta-analysis are preliminary and may be biased by the relatively small number of subjects, they still need to be validated by well-designed studies using larger samples in the future.

Polymorphisms in ERCC1 C8092A predict progression-free survival in metastatic/recurrent nasopharyngeal carcinoma treated with cisplatin-based chemotherapy

OBJECTIVES

We evaluated whether DNA repair gene polymorphisms had an effect on clinical outcomes in metastatic/recurrent nasopharyngeal carcinoma (NPC) patients treated with cisplatin-based chemotherapy.

MATERIALS AND METHODS

Clinical data of 101 patients with metastatic/recurrent NPC between 2004 and 2011 were reviewed. Five potentially functional polymorphisms (ERCC1 Asn118Asn, ERCC1 C8092A, XPD Lys751Gln, XRCC1 Arg399Gln and XRCC1 Arg280His) were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

RESULTS

The ERCC1 C8092A polymorphism was an independent predictor of PFS in Chinese NPC patients treated with cisplatin-based chemotherapy. Compared to the patients carrying the C/C genotype, the patients with the C/A or A/A genotype had an increased risk of disease progression on cisplatin-based chemotherapy (7.9 vs. 9.3 months; HR 1.61; 95 % CI 1.08-2.61; p = 0.047). However, no association between the other polymorphisms, response rate, disease progression and survival was detected in metastatic/recurrent NPC patients.

CONCLUSION

The ERCC1 C8092A polymorphism might be a useful predictive marker in metastatic/recurrent NPC patients treated with cisplatin-based chemotherapy. However, a large-scale prospective study is warranted to validate our findings.

MTHFR Glu429Ala and ERCC5 His46His polymorphisms are associated with prognosis in colorectal cancer patients: analysis of two independent cohorts from Newfoundland

Introduction

In this study, 27 genetic polymorphisms that were previously reported to be associated with clinical outcomes in colorectal cancer patients were investigated in relation to overall survival (OS) and disease free survival (DFS) in colorectal cancer patients from Newfoundland.

Methods

The discovery and validation cohorts comprised of 532 and 252 patients, respectively. Genotypes of 27 polymorphisms were first obtained in the discovery cohort and survival analyses were performed assuming the co-dominant genetic model. Polymorphisms associated with disease outcomes in the discovery cohort were then investigated in the validation cohort.

Results

When adjusted for sex, age, tumor stage and microsatellite instability (MSI) status, four polymorphisms were independent predictors of OS in the discovery cohort MTHFR Glu429Ala (HR: 1.72, 95%CI: 1.04–2.84, p = 0.036), ERCC5 His46His (HR: 1.78, 95%CI: 1.15–2.76, p = 0.01), SERPINE1 −675indelG (HR: 0.52, 95%CI: 0.32–0.84, p = 0.008), and the homozygous deletion of GSTM1 gene (HR: 1.4, 95%CI: 1.03–1.92, p = 0.033). In the validation cohort, the MTHFR Glu429Ala polymorphism was associated with shorter OS (HR: 1.71, 95%CI: 1.18–2.49, p = 0.005), although with a different genotype than the discovery cohort (CC genotype in the discovery cohort and AC genotype in the validation cohort). When stratified based on treatment with 5-Fluorouracil (5-FU)-based regimens, this polymorphism was associated with reduced OS only in patients not treated with 5-FU. In the DFS analysis, when adjusted for other variables, the TT genotype of the ERCC5 His46His polymorphism was associated with shorter DFS in both cohorts (discovery cohort: HR: 1.54, 95%CI: 1.04–2.29, p = 0.032 and replication cohort: HR: 1.81, 95%CI: 1.11–2.94, p = 0.018).

Conclusions

In this study, associations of the MTHFR Glu429Ala polymorphism with OS and the ERCC5 His46His polymorphism with DFS were identified in two colorectal cancer patient cohorts. Our results also suggest that the MTHFR Glu429Ala polymorphism may be an adverse prognostic marker in patients not treated with 5-FU.

GSTM1 copy number and promoter haplotype as predictors for risk of recurrence and/or second primary tumor in patients with head and neck cancer

The objective of this study was to determine copy number variant (CNV) and promoter genetic variants in glutathione S-transferase Mu class 1 (GSTM1) and the risk of recurrence (REC)/second primary tumor (SPT) in patients with previously diagnosed early stage head and neck cancer. Among 441 subjects, 133 experienced REC and/or an SPT, while 308 had single primary disease. TaqMan real-time polymerase chain reaction was used to measure the exact copy number of GSTM1 and direct sequencing was used to determine genetic variants in the GSTM1 promoter region. Multivariate Cox regression analysis was performed to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) associated with copy number and genetic variants. REC/SPT-free survival times were compared by constructing Kaplan–Meier curves and differences between curves were tested by logrank test. Results showed a significantly decreased REC/SPT (HR = 0.57; 95% CI = 0.35–0.95) and longer REC/SPT-free survival in subjects with at least two copies of GSTM1 compared with the GSTM1 homozygous deletion, but not in those with one copy of GSTM1. The −498G, −426G, and −339T alleles were significantly associated with REC/SPT, with HRs of 0.11 (0.02–0.85), 0.28 (0.11–0.74) and 2.02 (1.07–3.82), respectively. Kaplan–Meier survival analysis showed that the −498G, −426G, and −339C alleles were also significantly associated with increased REC/SPT-free survival. Further haplotype analysis showed the haplotype P^{−498G-−426G-−339C} carriers had decreased REC/SPT with a HR of 0.09 (95% CI 0.01–0.71) and increased REC/SPT-free survival compared with those with haplotype P^{−498C-−426A-−339T}. The P^{−498C-−426A-−339T}-containing reporter construct had significantly increased luciferase expression. These results suggest that the GSTM1 CNV and promoter haplotype are better predictors of REC/SPTs of head and neck cancer than just measuring the presence/absence of GSTM1.

Somatic evolution of head and neck cancer - biological robustness and latent vulnerability

Despite recent advancements in multidisciplinary treatments, the overall survival and quality of life of patients with advanced head and neck squamous cell carcinoma (HNSCC) have not improved significantly over the past decade. Molecular targeted therapies, which have been addressed and advanced by the concept of “oncogene addiction”, have demonstrated only limited successes so far. To explore a novel clue for clinically effective targeted therapies, we analyzed the molecular circuitry of HNSCC through the lens that HNSCC is an evolving system. In the trajectory of this somatic evolution, HNSCC acquires biological robustness under a variety of selective pressures including genetic, epigenetic, micro‐environmental and metabolic stressors, which well explains the major mechanism of “escaping from oncogene addiction”. On the other hand, this systemic view appears to instruct us approaches to target latent vulnerability of HNSCC that is masked behind the plasticity and evolvability of this complex adaptive system.

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There is an urgent need to develop a novel conceptual framework for the treatment of HNSCC.

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The biological robustness of HNSCC was analyzed through a somatic evolution model.

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This model well explains the mechanism of “escaping from oncogene addiction”.

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We discuss about the possible approaches to target vulnerability of evolving HNSCC.

Genetic sequence variants and the development of secondary primary cancers in patients with head and neck cancers

BACKGROUND

Secondary primary cancers (SPCs), a major cause of morbidity and mortality in head and neck cancers (HNCs), are commonly associated with field cancerization. We comprehensively evaluated 23 germline sequence variants (from published literature) in 17 genes from 7 biological pathways associated with the HNC survival. Because cancer prognosis correlates with disease aggressiveness, the factors that determine aggressive disease may influence field cancerization process to favor SPC development. We thus hypothesized that the same sequence variants associated with HNC survival can also be associated with SPC.

METHODS

Germline DNA from 531 stage I-II radiation-treated HNC patients (originally recruited for an alpha-tocopherol/beta-carotene placebo-controlled secondary prevention clinical trial) were genotyped, and analyzed using Cox proportional hazards models, stratified by treatment arm, adjusting for clinical prognostic factors.

RESULTS

The majority of SPCs were of lung and HNCs. Median follow-up time was 5 years. SPCs were diagnosed in 21% of patients. The 5-year SPC-free survival was 79%. All but 1 evaluated sequence variant were not associated with SPC. There was a strong association of the DNA (cytosine-5-)-methyltransferase 3 beta (DNMT3B) sequence variant, DNMT3B:C149T (rs2424913) with SPC: the adjusted hazard ratio (aHR) for TT versus CC was 2.23 (1.32-3.78; P = .003), whereas each variant T allele was associated with an aHR of 1.49 (1.15-1.95; P = .003).

CONCLUSIONS

A functional sequence variant in DNMT3B is associated with the development of SPCs in HNC early stage patients treated with radiation. Aberrant DNA methylation may be an important modulator of SPC development in at-risk individuals with HNCs.

Novel targeted therapies in head and neck cancer

INTRODUCTION

Molecularly targeted therapy, with the potential for increased selectivity and fewer adverse effects, hold promise in the treatment of HNSCC.

AREAS COVERED

Targeted agents for HNSCC expected to improve the effectiveness of current therapy including HER family, Src-family kinase, cell cycle, MET, AKT, HDAC, PARP, COX inhibitors and antiangiogenesis.

EXPERT OPINION

Epidermal growth factor receptor inhibitors are established in HNSCC and the need now is to find biomarkers for sensitivity to better select patients. Moreover, other pathway inhibitors hold significant promise and are being tested in clinical trials. Angiogenesis inhibition is likely to yield only modest efficacy alone but may augment existing standards. Lastly, one clinical arena where targeted therapies may find secure purchase is in the adjuvant or prevention setting where minimal or preneoplastic disease can be affected by inhibition of a single or few targets.

Polymorphisms in GSTM1 and XPD genes predict clinical outcome in advanced oral cancer patients treated with postoperative radiotherapy

Polymorphisms in metabolic and DNA repair genes may alter protein function, consequently affecting patients' response to chemo/radiotherapy. We retrospectively assessed whether polymorphisms of glutathione-S-transferase genes GSTM1 (deletion), GSTT1 (deletion), GSTP1 (Ile105Val, rs1695), and DNA repair genes hOGG1 (Ser326Cys, rs1052133), XRCC1 (Arg194Trp, rs1799782, and Arg399Gln, rs25487), XPD (Asp312Asn, rs1799793, and Lys751Gln, rs13181) can predict clinical outcome in 187 oral squamous cell carcinoma patients treated with postoperative radiotherapy. The Cox proportional hazards model was used to evaluate the role of polymorphic genotypes on relapse-free (RFS) and disease-specific (DSS) survival. Deletion polymorphism of GSTM1 gene was significantly associated with DSS. The rs1799793 variant allele showed significant protection in both DSS and RFS. Significant increase in RFS but not in DSS was observed with polymorphic rs13181. The combined analysis of GSTM1 and XPD polymorphisms revealed favorable effect on survival. GSTM1 and XPD variant alleles, independently as well as in combination may serve as important predictors of clinical outcome in radiotherapy-treated OSCC patients.

Validation of genetic sequence variants as prognostic factors in early-stage head and neck squamous cell cancer survival

PURPOSE

From the published literature, we identified 23 germ line sequence variants in 17 genes from hypothesis-generating studies that were associated with prognosis of head and neck cancer, including sequence variants of DNA repair (ERCC1, ERCC4, ERCC5, MSH2, XPA, ERCC2, XRCC1, XRCC3), DNA methylation (DNMT3B), cell cycle and proliferation (CCND1, TP53), xenobiotic metabolism (GSTM1, GSTT1, CYP2D6), metastatic -potential (MMP3), immunologic (CTLA4), and growth factor pathways (FGFR4). The purpose of this study was to validate the role of these 23 sequence variants for overall (OS) and disease-free survival (DFS) in a large, comprehensive, well-annotated data set of patients with head and neck cancer.

EXPERIMENTAL DESIGN

We genotyped these sequence variants in 531 patients with stage I and II radiation-treated head and neck cancer (originally recruited for an alpha-tocopherol/beta-carotene placebo-controlled secondary prevention study), and analyzed using Cox proportional hazards models, stratified by treatment arm, adjusting for clinical prognostic factors.

RESULTS

Two OS associations were statistically significant for each variant allele when compared with the wild-type: CTLA4: A49G [rs231775; adjusted HR (aHR), 1.32 (1.1-1.6); P = 0.01] and XRCC1: Arg339Gln [rs25487; aHR, 1.28 (1.05-1.57); P = 0.02]. Both of these sequence variants had significant results in the opposite direction as prior published literature. Two DFS associations were of borderline significance in the same direction as prior literature: ERCC2: Lys751Gln [rs13181; aHR, 0.80 (0.6-1.0); P = 0.05] and TP53: Arg72Pro [rs1042522; aHR, 1.28 (1.0-1.6); P = 0.03], comparing number of variant alleles with reference of zero variants.

CONCLUSIONS

None of the prognostic sequence variants previously published was validated for OS in our patients with early-stage radiation-treated head and neck cancer, though rs1381and rs1042522 had borderline significant association with DFS.

Effects of ERCC2 Lys751Gln (A35931C) and CCND1 (G870A) polymorphism on outcome of advanced-stage squamous cell carcinoma of the head and neck are treatment dependent

BACKGROUND

Germline variation in DNA damage response may explain variable treatment outcomes in squamous cell carcinoma of the head and neck (SCCHN). By grouping patients according to stage and radiation treatment, we compared SCCHN survival with regard to ERCC2 A35931C (Lys751Gln, rs13181) and CCND1 G870A (Pro241Pro, rs9344) genotypes.

METHODS

In a hospital-based SCCHN case series (all white, 24.7% female, mean age 58.4 years), this treatment-outcome cohort study genotyped 275 stage III-IV cases that were initially treated with radiation (with or without chemotherapy) and 80 stage III-IV and 130 stage I-II cases that were initially treated without radiation or chemotherapy and used Kaplan-Meier and Cox regression analyses to compare genotype groups on the basis of overall, disease-specific, progression-free, and recurrence-free survival rates.

RESULTS

ERCC2 35931 AA predicted worse survival in stage III-IV cases treated with radiation [multiply-adjusted HR = 1.66, 95% confidence interval (CI), 1.15-2.40; HR over the first 3 follow-up years = 1.92; 95% CI, 1.28-2.88] and better survival in stage III-IV cases not treated with radiation (HR = 0.26; 95% CI, 0.11-0.62). Although not associated with survival in stage III-IV cancers treated with radiation (HR = 1.00; 95% CI, 0.67-1.51), CCND1-870 GG predicted better survival in stage III-IV cancers not treated with radiation (HR = 0.14; 95% CI, 0.04-0.50). Survival in stage I-II did not depend on ERCC2 A35931C or CCND1 G870A genotype.

CONCLUSIONS

Although promoting tumor progression in untreated patients, germline differences in DNA-repair or cell-cycle control may improve treatment outcome in patients treated with DNA-damaging agents.

IMPACT

ERCC2 A35931C may help distinguish advanced stage SCCHN with better outcomes from radiation treatment.

Education, tobacco smoking, alcohol consumption, and IL-2 and IL-6 gene polymorphisms in the survival of head and neck cancer

The association of education, tobacco smoking, alcohol consumption, and interleukin-2 (IL-2 +114 and -384) and -6 (IL-6 -174) DNA polymorphisms with head and neck squamous cell carcinoma (HNSCC) was investigated in a cohort study of 445 subjects. IL-2 and IL-6 genotypes were determined by real-time PCR. Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI) of disease-specific survival according to anatomical sites of the head and neck. Mean age was 56 years and most patients were males (87.6%). Subjects with 5 or more years of schooling had better survival in larynx cancer. Smoking had no effect on HNSCC survival, but alcohol consumption had a statistically significant effect on larynx cancer. IL-2 gene +114 G/T (HR = 0.52; 95%CI = 0.15-1.81) and T/T (HR = 0.22; 95%CI = 0.02-3.19) genotypes were associated with better survival in hypopharynx cancer. IL-2 +114 G/T was a predictor of poor survival in oral cavity/oropharynx cancer and larynx cancer (HR = 1.32; 95%CI = 0.61-2.85). IL-2 -384 G/T was associated with better survival in oral cavity/oropharynx cancer (HR = 0.80; 95%CI = 0.45-1.42) and hypopharynx cancer (HR = 0.68; 95%CI = 0.21-2.20), but an inverse relationship was observed for larynx cancer. IL-6 -174 G/C was associated with better survival in hypopharynx cancer (HR = 0.68; 95%CI = 0.26-1.78) and larynx cancer (HR = 0.93; 95%CI = 0.42-2.07), and C/C reduced mortality in larynx cancer. In general, our results are similar to previous reports on the value of education, smoking, alcohol consumption, and IL-2 and IL-6 genetic polymorphisms for the prognosis of HNSCC, but the risks due to these variables are small and estimates imprecise.

Pharmacogenetic and germline prognostic markers of lung cancer

INTRODUCTION

Lung cancer is the leading global cause of cancer-related mortality. Interindividual variability in treatment response and cancer outcomes has focused attention on genetic polymorphisms as prognostic markers. We evaluated the overall contribution of candidate polymorphism association studies to our current understanding of the genetic predictors of lung cancer outcomes.

METHODS

We examined the results of 90 studies that evaluated associations between genetic polymorphisms and lung cancer outcomes published between January 1990 and May 2009.

RESULTS

A total of 170 genetic variations in 90 studies were identified. Overall survival was a primary outcome in 81% of the studies and toxicity in 19%. Candidate polymorphisms in the DNA repair/synthesis pathway were the most frequently studied. Strong evidence in large-scale confirmatory studies of any single polymorphism was lacking. Polymorphisms of EGFR, XRCC1, and ERCC1 were associated with pharmacogenetic outcomes, whereas polymorphisms of MDM2, p53, and GSTM1 were associated with prognostic outcomes. All remaining polymorphisms had results lacking or failing replication testing. Heterogeneity in study populations, incomplete reporting of important population or study characteristics, inadequate power, and inconsistencies in methodology were common.

CONCLUSIONS

Although the quality of existing studies involving the candidate polymorphism approach is highly variable, a small set of candidate polymorphisms was identified as potential biomarkers of clinical or pharmacogenetic outcome and would benefit from further replication testing. Newer approaches including haplotype tagging, pathway, genome-wide association, and combination methods with validative approaches may facilitate a more accurate prediction of lung cancer outcomes by genetic variation.

The molecular biology of head and neck cancer

Head and neck squamous cell carcinomas (HNSCCs) are caused by tobacco and alcohol consumption and by infection with high-risk types of human papillomavirus (HPV). Tumours often develop within preneoplastic fields of genetically altered cells. The persistence of these fields after treatment presents a major challenge, because it might lead to local recurrences and second primary tumours that are responsible for a large proportion of deaths. Aberrant signalling pathways have been identified in HNSCCs and inhibition of epidermal growth factor receptor (EGFR) has proved a successful therapeutic strategy. In this Review, we discuss the recent literature on tumour heterogeneity, field cancerization, molecular pathogenesis and the underlying causative cancer genes that can be exploited for novel and personalized treatments of patients with HNSCC.

The molecular biology of head and neck cancer

Head and neck squamous cell carcinomas (HNSCCs) are caused by tobacco and alcohol consumption and by infection with high-risk types of human papillomavirus (HPV). Tumours often develop within preneoplastic fields of genetically altered cells. The persistence of these fields after treatment presents a major challenge, because it might lead to local recurrences and second primary tumours that are responsible for a large proportion of deaths. Aberrant signalling pathways have been identified in HNSCCs and inhibition of epidermal growth factor receptor (EGFR) has proved a successful therapeutic strategy. In this Review, we discuss the recent literature on tumour heterogeneity, field cancerization, molecular pathogenesis and the underlying causative cancer genes that can be exploited for novel and personalized treatments of patients with HNSCC.

Germline genetic variation, cancer outcome, and pharmacogenetics

Studies of the role of germline or inherited genetic variation on cancer outcome can fall into three distinct categories. First, the impact of highly penetrant but lowly prevalent mutations of germline DNA on cancer prognosis has been studied extensively for BRCA1 and BRCA2 mutations as well as mutations related to hereditary nonpolyposis colorectal cancer syndrome. These mainly modest-sized analyses have produced conflicting results. Although some associations have been observed, they may not be independent of other known clinical or molecular prognostic factors. Second, the impact of germline polymorphisms on cancer prognosis is a burgeoning field of research. However, a deeper understanding of potentially confounding somatic changes and larger multi-institutional, multistage studies may be needed before consistent results are seen. Third, research examining the impact of germline genetic variation on differential treatment response or toxicity (pharmacogenetics) has produced some proof-of-principle results. Putative germline pharmacogenetic predictors of outcome include DPYD polymorphisms and fluorouracil toxicity, UGT1A1 variation and irinotecan toxicity, and CYP2D6 polymorphisms and tamoxifen efficacy, with emerging data on predictors of molecularly targeted or biologic drugs. Here we review data pertaining to these germline outcome and germline toxicity relationships.

A let-7 microRNA-binding site polymorphism in the KRAS 3' UTR is associated with reduced survival in oral cancers

MicroRNA (miRNA)-binding site polymorphisms that could contribute to disease risk and prognosis are rapidly being identified and investigated as this genetic variation may have a potentially profound impact on human health. A recently described variant allele in the KRAS 3' untranslated region that arises in the let-7 miRNA complementary site (KRAS-LCS6) and leads to increased KRAS expression in lung cancer was examined for its association with the occurrence of head and neck squamous cell carcinoma (HNSCC). We examined the prevalence of the KRAS-LCS6 variant allele in a population-based case-control study of HNSCC to determine if this KRAS-LCS6 genotype was associated with disease occurrence and patient survival. Although the KRAS-LCS6 variant genotype was not associated with the overall risk of HNSCC, cases with the KRAS-LCS6 variant genotype had significantly reduced survival [hazard ratio (HR), 1.6; 95% confidence interval (CI), 1.0-2.5] in models controlled for confounders of survival. This risk was greatest in cases of oral cavity carcinoma (HR, 2.7; 95% CI, 1.4-5.3). These data demonstrate that cases with the KRAS-LCS6 variant have significantly reduced survival time and suggest that this variant may alter the phenotype or therapeutic response of this disease.

Genetic polymorphisms in DNA base excision repair gene XRCC1 and the risk of squamous cell carcinoma of the head and neck

Background

The genes of base excision repair (BER) pathway have been extensively studied in the association with various human cancers. We performed a case-control study to test the association between two common single nucleotide polymorphisms (SNPs) of XRCC1 gene with human head and neck squamous cell carcinoma (HNSCC).

Methods

The genotype analysis of Arg194Trp and Arg399Gln gene polymorphisms for 92 HNSCC patients and 124 controls of cancer free subjects, in Polish population were performed using the PCR-based restriction fragment length polymorphism (PCR-RFLP) with endonuclease MspI.

Results

No altered risk has been found individually for these SNPs, however haplotypes analysis showed high association with head and neck cancer. The highest frequency, according to wild-type of Arg194Arg and Arg399Arg genotypes, was identified for Arg194Trp-Arg399Arg haplotype (OR, 2.96; 95% CI, 1.01–8.80).

Conclusion

Finally, we identified the combined Arg194Trp-Arg399Arg genotype of base excision repair gene XRCC1 that was associated with HNSCC and may have an impact on identification of a high-risk cancer population.

Head and neck squamous cell carcinoma is not associated with interleukin-18 promoter gene polymorphisms: a case–control study

Objective:

To investigate the association of two functional single nucleotide polymorphisms in the promoter region of the interleukin-18 gene, at positions −607 and −137, with head and neck squamous cell carcinoma.

Design:

Genomic deoxyribonucleic acid was extracted, by the salting-out method, from peripheral blood leukocytes. Single nucleotide polymorphisms of the interleukin-18 gene at positions −607 (cytosine/adenine) and −137 (guanine/cytosine) were analysed by sequence-specific polymerase chain reaction.

Subjects:

One hundred and eleven patients (86 men and 25 women; mean age 56.7±13.7 years) and 212 regional controls (165 men and 47 women; mean age 53.3±12.2 years) were studied. Control subjects comprised healthy volunteers or cancer-free individuals presenting with otolaryngological disease. The diagnosis of squamous cell carcinoma was confirmed histopathologically. Various clinical parameters were collected at diagnosis, including tumour site, tumour size, lymph node involvement, distant metastasis and stage.

Results:

There was no significant association between the allele, genotype or haplotype frequencies of the two single nucleotide polymorphisms of the interleukin-18 promoter and the head and neck squamous cell carcinoma susceptibility or clinical parameters at diagnosis.

Conclusion:

Interleukin-18 polymorphisms at positions −607 and −137 did not confer susceptibility to head and neck squamous cell carcinoma in southern Iranian patients.