Squamous Cell Carcinoma Of The Head And Neck Cases Research Articles

Co-expression of fibroblast growth factor receptor 3 with mutant p53, and its association with worse outcome in oropharyngeal squamous cell carcinoma.

Fibroblast growth factor receptor 3 (FGFR3) is expressed in squamous cell carcinoma of the head and neck (SCCHN) including oropharyngeal squamous cell carcinoma (OPSCC) and is a potential therapeutic target. However, information on its correlation with other relevant cancer related proteins stratified by p16 status and its prognostic significance in OPSCC is limited. We examined FGFR3 expression and its correlation with clinical characteristics, p16 status, and mutant p53 (mp53) among 220 retrospectively collected OPSCC cases and 40 prospectively collected SCCHN cases, including a majority of OPSCC. Correlations of FGFR3 Weighted Index (WI) with p16 status and mp53 WI as well as its association with disease-free survival (DFS) and overall survival (OS) were evaluated. FGFR3 expression was detected in 61% and 70% of cases in cohorts 1 and 2, respectively. FGFR3 level was significantly higher in p16-negative tumors in both cohorts (p<0.001 and 0.006). FGFR3 expression was highly correlated with mp53 expression in both p16 + and p16– OPSCC (p<0.0001 and p = 0.0006, respectively). In cohort 1, univariate analysis showed that FGFR3 was associated with DFS but not OS. Kaplan-Meier analysis showed that higher FGFR3 and mp53 level correlated with worse DFS (p = 0.025) and OS (p = 0.009). As expected, p16 positive status was associated with improved OS and DFS (p<0.001 for both). Our results suggest that high FGFR3 expression is associated with p16 negative status and mp53 expression in OPSCC and correlates with a worse clinical outcome. The biological relationship between FGFR3 and mp53 in OPSCC deserves further investigation.

Small Cell and Squamous Cell Carcinomas of the Head and Neck: Comparing Incidence and Survival Trends Based on Surveillance, Epidemiology, and End Results (SEER) Data.

Small cell carcinomas of the head and neck (SmCCHNs) are rare neoplasms with an unfavorable prognosis. Population-based data describing survival and prognostic factors for SmCCHN are limited. Data were obtained from the U.S. National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database for 1973-2013. Patient and tumor-related characteristics for SmCCHN were compared with those for squamous cell carcinoma of the head and neck (SCCHN). Survival was compared by constructing Kaplan-Meier curves and Cox proportional hazard models with and without propensity score matching. The data set included 609 SmCCHN and 227,943 SCCHN cases. Both histological subtypes were more common in men than women and more common in white patients. SmCCHN was most likely to originate in the larynx, glottis and hypopharynx, or salivary glands and to present with more advanced stage and grade. SCCHN was most likely to originate in the oral cavity and was found infrequently in the salivary glands. Overall 5- and 10-year survival estimates were 27% and 18% for SmCCHN and 46% and 31% for SCCHN, respectively. In multivariable survival analyses adjusting for age, sex, race, marital status, year of diagnosis, stage, grade, and receipt of radiation, the hazard ratio (HR) comparing SmCCHN with SCCHN was 1.53 with a 95% confidence interval (CI) from 1.39 to 1.68. Average 5-year survival varied widely between the histologic types when comparing tumor sites: 14.5% for SmCCHN versus 48.9% for SCCHN in the oropharynx. In propensity score matched analyses, the corresponding HR was 1.27 (95% CI, 1.15-1.40). Compared with SCCHN, SmCCHN carries a worse survival and is more likely to present with more advanced stage. Small cell carcinoma of the head and neck (SmCCHN) is a rare subtype of head and neck cancer. In this Surveillance, Epidemiology, and End Results (SEER) data analysis, the characteristics and survival of SmCCHN are compared with those of the common squamous cell carcinoma of the head and neck. Results show that SmCCHN carries a worse prognosis and tends to present at a more advanced stage; SmCCHN also is ten times more likely to originate from the salivary glands. These findings may have implications for clinical practice, as location of the tumor may strongly associate with the pathologic diagnosis. If a SmCCHN is diagnosed, a disseminated disease is likely; hence vigilance in staging procedures is indicated.

Endothelial nitric oxide synthase gene polymorphisms modulate the risk of squamous cell carcinoma of head and neck in north Indian population

BackgroundNitric oxide (NO) is found to have both tumour promoting and inhibiting properties. Nitric oxide (NO) is synthesized by three isoforms of nitric oxide synthase (NOS) enzymes and endothelial NOS (eNOS) is one of them. Polymorphisms in eNOS 894G > T (rs1799983) and eNOS intron 4a/b geneS could modulate the risk for developing SCCHN by regulating the level of nitric oxide. ObjectiveIn this study we evaluated the association of eNOS 894G > T (rs1799983) and intron 4a/b polymorphisms with the plasma nitrite level and the risk of Squamous cell carcinoma of the head and neck (SCCHN). Materials and methodsA total of 352 subjects were genotyped for the above said polymorphisms. Genotypes were correlated with plasma nitrite level of study subjects. ResultsCompared to GG homozygote of 894G > T polymorphism a significantly increased risk of SCCHN was observed with TT homozygote (p = 0.03, OR = 2.72, 95% CI 1.14–6.50). In comparison to carrier of ‘b’ allele, ‘a’ allele carrier for intron 4a/b polymorphism were at increased risk to develop high stage diseases (p = 0.00, OR 8.67 and 95% CI 3.76–19.99). The haplotype bT constituted from 894G > T and intron 4a/b polymorphisms also showed association with increased susceptibility for SCCHN (p = 0.038 OR = 1.66, 95% CI 1.03–2.63). Plasma nitrite level was significantly higher in cases compared to control (p = 0.047). The level of plasma nitrite was also higher in individuals with TT genotype compared to those with GG genotype (p = 0.012 in SCCHN cases and 0.088 in control).Conclusions: Our results suggest that eNOS 894G > T and intron 4a/b polymorphisms influence the risk of SCCHN and, eNOS 894G > T polymorphism modulate the risk of disease by modulating plasma nitrite level.

Interaction between known risk factors for head and neck cancer and socioeconomic status: the Carolina Head and Neck Cancer Study

Prior studies of squamous cell carcinoma of the head and neck (SCCHN) have explored the effect of socioeconomic status (SES) as an independent risk factor; however, none have investigated the interaction of known risk factors with SES. We examined this using the North Carolina Head and Neck Cancer Epidemiology Study, a population-based case–control study. Incident cases of SCCHN from North Carolina between 2002 and 2006 (n = 1,153) were identified and age, sex, and race-matched controls (n = 1,267) were selected from driver license records. SES measures included household income, educational attainment, and health insurance. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Current smoking was more strongly associated with SCCHN among those households making < $20,000/year [OR 5.11 (3.61–6.61)] compared to household incomes > $50,000/year [OR 2.47 (1.69–3.25); p interaction < 0.001]. Current drinking was more strongly associated with SCCHN in household incomes < $20,000 [OR 2.91 (2.05–3.78)] compared to > $50,000/year [1.28 (0.97–1.58); p interaction < 0.001]. Current drinkers with less than high school education or income < $20,000 had nearly threefold odds of never-drinkers in the same SES category [OR 2.91 (2.05–3.78); 2.09 (1.39–2.78), respectively]. Our results suggest that the relationship of smoking and alcohol use may be stronger among those of lower SES.

Outcomes of chemoradiation (CRT) for locoregionally advanced (LRA)squamous cell carcinoma of the head and neck (SCCHN): Outcomes with weekly cisplatin (WC) in an academic community based hospital.

e18081Background: CRT is a component of treatment (tx) for LRA SCCHN. High dose cisplatin (HDC) on weeks 1, 4, 7 is a standard but toxic regimen. Additionally, many cases of SCCHN are now attributa...

In Vitro and In Vivo Synergistic Antitumor Activity of the Combination of BKM120 and Erlotinib in Head and Neck Cancer: Mechanism of Apoptosis and Resistance

We previously reported that the EGFR-targeted inhibitor erlotinib induces G1 arrest of squamous cell carcinoma of the head and neck (SCCHN) cell lines without inducing significant apoptosis. Large-scale genomic studies suggest that >50% of SCCHN cases have activation of PI3K pathways. This study investigated whether cotargeting of EGFR and PI3K has synergistic antitumor effects and apoptosis induction. We examined growth suppression, apoptosis, and signaling pathway modulation resulting from single and combined targeting of EGFR and PI3K with erlotinib and BKM120, respectively, in a panel of SCCHN cell lines and a xenograft model of SCCHN. In a panel of 12 cell lines, single targeting of EGFR with erlotinib or PI3K with BKM120 suppressed cellular growth without inducing significant apoptosis. Cotargeting of EGFR and PI3K synergistically inhibited SCCHN cell line and xenograft tumor growth, but induced variable apoptosis; some lines were highly sensitive, others were resistant. Mechanistic studies revealed that the combination inhibited both axes of the mTORC1 (S6 and 4EBP1) pathway in apoptosis-sensitive cell lines along with translational inhibition of Bcl-2, Bcl-xL, and Mcl-1, but failed to inhibit p-4EBP1, Bcl-2, Bcl-xL, and Mcl-1 in an apoptosis-resistant cell line. siRNA-mediated knockdown of eIF4E inhibited Bcl-2 and Mcl-1 and sensitized this cell line to apoptosis. Our results strongly suggest that cotargeting of EGFR and PI3K is synergistic and induces apoptosis of SCCHN cell lines by inhibiting both axes of the AKT-mTOR pathway and translational regulation of antiapoptotic Bcl-2 proteins. These findings may guide the development of clinical trials using this combination of agents. Mol Cancer Ther; 16(4); 729-38. ©2017 AACR.

Targeted next-generation sequencing identifies molecular subgroups in squamous cell carcinoma of the head and neck with distinct outcome after concurrent chemoradiation

Based on epidemiological (HPV status, smoking habits) and clinical risk factors (T/N stage), three subgroups of patients suffering from locally advanced oropharyngeal carcinoma with significantly different outcome after concurrent chemoradiation (cCRTX) can be distinguished. Mutational profiling by targeted next-generation sequencing (NGS) might further improve risk stratification. Patients with stage IV squamous cell carcinoma of the oropharynx and hypopharynx who had been enrolled in a randomized phase III trial (ARO-0401) comparing two regimens of cCRTX and from whom archival tumor specimens were available were included. The HPV status was determined by p16 immunostaining and detection of HPV DNA. Targeted NGS covering 45 genes frequently altered in squamous cell carcinoma of the head and neck (SCCHN) was applied for detection of non-synonymous somatic and germline mutations. Interference of mutational profiles with cCRTX efficacy was determined. The prognostic value of the 'Ang' risk model could be confirmed in the total biomarker study cohort (N = 175) as well as the patient subgroup for which mutational profiles could be established (N = 97). Mutations in genes involved in phosphoinositide 3-kinase (PI3K), receptor tyrosine kinase (RTK), and p53 signaling pathways were significantly enriched in the low- (N = 7), intermediate- (N = 20), and high-risk group (N = 70), respectively. Mutations in TP53 identified a subgroup of high-risk patients with dismal outcome after cCRTX. No prognostic relevance was observed for mutations in PI3K and RTK signaling pathways in the low- and intermediate-risk groups, respectively. Mutated NOTCH1 and two functional KDR germline variants (rs2305948, rs1870377) were associated with improved outcome in all risk groups. All genetic markers (TP53, NOTCH1, KDR) remained independent prognosticators of OS in the multivariate model. A potential of targeted NGS for risk classification of SCCHN cases beyond HPV status and clinical factors was demonstrated.

Treatment of Elderly Patients with Squamous Cell Carcinoma of the Head and Neck.

The demographics of squamous cell carcinoma of the head and neck (SCCHN) is marked by a growing number of patients aged 65 and over, which is in line with global projections for other cancer types. In developed countries, more than half of new SCCHN cases are diagnosed in older people, and in 15 years from now, the proportion is expected to rise by more than 10%. Still, a high-level evidence-based consensus to guide the clinical decision process is strikingly lacking. The available data from retrospective studies and subset analyses of prospective trials suffer from a considerable underrepresentation of senior participants. The situation is even more challenging in the recurrent and/or metastatic setting, where usually only palliative measures are employed. Nevertheless, it is becoming clear that, if treated irrespective of chronological age, fit elderly patients in a good general condition and with a low burden of comorbidities may derive a similar survival advantage as their younger counterparts. Despite that, undertreatment represents a widespread phenomenon and, together with competing non-cancer mortality, is suggested to be an important cause of the worse treatment outcomes observed in this population. Due to physiological changes in drug metabolism occurring with advancing age, the major concerns relate to chemotherapy administration. In locally advanced SCCHN, concurrent chemoradiotherapy in patients over 70 years remains a point of controversy owing to its possibly higher toxicity and questionable benefit. However, accumulating evidence suggests that it should, indeed, be considered in selected cases when biological age is taken into account. Results from a randomized trial conducted in lung cancer showed that treatment selection based on a comprehensive geriatric assessment (CGA) significantly reduced toxicity. However, a CGA is time-consuming and not necessary for all patients. To overcome this hurdle, geriatric screening tools have been introduced to decide who needs such a full evaluation. Among the various screening instruments, G8 and Flemish version of the Triage Risk Screening Tool were prospectively verified and found to have prognostic value. We, therefore, conclude that also in SCCHN, the application of elderly specific prospective trials and integration of clinical practice-oriented assessment tools and predictive models should be promoted.

Telomere length, genetic variants and risk of squamous cell carcinoma of the head and neck in Southeast Chinese.

Telomere dysfunction participates in malignant transformation and tumorigenesis. Previous studies have explored the associations between telomere length (TL) and cancer susceptibility; however, the findings are inconclusive. The associations between genetic variants and TL have been verified by quite a few genome-wide association studies (GWAS). Yet, to date, there was no published study on the relationship between TL, related genetic variants and susceptibility to squamous cell carcinoma of the head and neck (SCCHN) in Chinese. Hence, we detected relative telomere length (RTL) by using quantitative PCR and genotyped seven selected single nucleotide polymorphisms by TaqMan allelic discrimination assay in 510 SCCHN cases and 913 controls in southeast Chinese. The results showed that RTL was significantly associated with SCCHN risk [(adjusted odds ratio (OR) = 1.19, 95% confidence interval (CI) = 1.08–1.32, P = 0.001]. Furthermore, among seven selected SNPs, only G allele of rs2736100 related to RTL in Caucasians was significantly associated with both the decreased RTL (P = 0.002) and the increased susceptibility to SCCHN in Chinese (additive model: adjusted OR = 1.17, 95%CI = 1.00–1.38, P = 0.049). These findings provide evidence that shortened TL is a risk factor for SCCHN, and genetic variants can contribute to both TL and the susceptibility to SCCHN in southeast Chinese population.

Acetylated Tubulin (AT) as a Prognostic Marker in Squamous Cell Carcinoma of the Head and Neck

Acetylated tubulin (AT) expression has been proposed as a marker for sensitivity to taxane chemotherapy. We wanted to explore AT as a prognostic marker in squamous cell carcinoma of the head and neck (SCCHN). We assessed AT expression in archival tissue from our institutional tissue bank of primary SCCHN specimens. We also examined AT expression on pre-therapy tissues of patients with SCCHN receiving induction chemotherapy with docetaxel, cisplatin and 5FU (TPF IC). AT expression was assessed on archival cases of SCCHN with (N = 63) and without (N = 82) locoregional lymph node metastases (LNM). The predominant tumor site was oral cavity (52 %). Immunohistochemistry staining was based on staining intensity and percentage of tumor cells stained to create a weighted index (WI). A total of nine patients who received TPF IC were evaluable for response by RECIST and also had pre-therapy tissues available. A significant independent correlation between AT and tumor grade (p = 0.001) and primary location (p = 0.008) was noted. There was a trend of higher AT in patients with presence of LNM (p = 0.052) and a trend in improved OS for patients with an AT WI below the median compared to those above the median for patients with no LNM (p = 0.054). For patients treated with induction TPF, we observed an inverse correlation between AT expression and response to TPF IC (p = 0.0071). AT expression is correlated with tumor grade and primary site. There was an observed trend correlating AT with presence nodal metastases. The observed inverse correlation with response to taxane based chemotherapy needs validation in a larger sample size.

Acetylated tubulin and risk of nodal metastases in squamous cell carcinoma of the head and neck (SCCHN).

5560 Background: We previously established that AT expression predicts for response to chemotherapy in SCCHN (Saba et al, AACR 2010 meeting abstr 3744). We wanted to further examine the relation of AT expression and nodal metastases in SCCHN. Methods: We assessed AT expression in archival tissue specimens from primary SCCHN cases with (50 cases) and without (53 cases) lymph node metastases (NM) using standard immunohistochemistry (IHC). Clinical characteristics of patients were retrieved from the department of pathology under the guidelines of the institutional review board (IRB). IHC staining for AT was scored based on intensity and percentage of tumor cells stained: 0 = no staining, 1+ = weak, 2+ = moderate, 3+ = moderate to high, 4+ = high and a weighted index (WI) was calculated as percent stain x stain intensity. Wilcoxon two-sample test and Kruskal-Wallis test were used to estimate the relationships of the WI with nodal metastasis, node status, primary tumor location, grade, and stage. Log-rank test was used to examine the difference in OS and DFS among four groups based on quartiles of the WI. A Cox proportional hazard model was employed to estimate the adjusted effect of WI on OS and DFS. Results: A higher AT expression was associated with nodal metastasis (p=0.0155) and higher stage (p=0.0311). A lower AT expression was associated with oral cavity primary (p=0.0107). After adjusting for age, gender, race, and smoking status, a lower AT expression was significantly associated with better DFS in the subset of patients with NM by multivariate analysis (HR=1.008; 95% CI=1.002- 1.014; p=0.0123). Among patients with no NM there was a marginally significant difference in OS among four different groups based on quartiles of AT expression (p=0.0765). Conclusions: High AT expression is associated with nodal metastases in SCCHN and may be a marker of poor prognosis in patients with node positive disease. The value of AT as a prognostic marker in SCCHN needs to be better defined. This work is supported by a SPORE CDP Grant P50 CA128613-03 to NFS.

Telomere Length and TERT Functional Polymorphisms Are Not Associated with Risk of Squamous Cell Carcinoma of the Head and Neck

Recent studies reported associations of the relative telomere length (RTL) and TERT variants with risk of several cancers, which have not been comprehensively investigated in squamous cell carcinoma of the head and neck (SCCHN). We detected RTL in peripheral blood lymphocytes and genotyped six selected functional single-nucleotide polymorphisms (SNP) of the TERT gene in 888 SCCHN cases and 885 cancer-free controls of non-Hispanic whites. Overall, we did not observe significant associations between RTL and SCCHN risk (adjusted OR = 0.97; 95% CI = 0.80-1.17 for below versus above the median; P(trend) = 0.618) nor between the six TERT SNPs and SCCHN risk. We also found no associations between RTL and TERT SNPs. Our results suggest that RTL and TERT functional polymorphisms may not play a major role in the etiology of SCCHN. Large prospective studies are needed to validate our findings. Although our results suggest no association among RTL, TERT functional polymorphisms, and SCCHN risk, this study may contribute to future meta-analysis.

Expression of Amphiregulin and EGFRvIII Affect Outcome of Patients with Squamous Cell Carcinoma of the Head and Neck Receiving Cetuximab–Docetaxel Treatment

Constitutive activation of epidermal growth factor receptor (EGFR) as a result of gene amplification, mutation, or overexpression of its ligands has been associated with response to EGFR targeting strategies. The role of these molecular mechanisms for the responsiveness of squamous cell carcinoma of the head and neck (SCCHN) to cetuximab-containing regimens remains unknown. Tumor biopsies from 47 patients, enrolled in a single-arm phase II multicenter study for second-line treatment of recurrent or metastatic SCCHN with cetuximab and docetaxel, were analyzed by immunohistochemistry for expression of EGFR, its deletion variant III (EGFRvIII) and its ligand amphiregulin (AREG). The relation between expression levels and disease control rate (DCR) was evaluated by logistic regression. Association between expression levels, progression-free survival (PFS), and overall survival (OS) was determined by Kaplan-Meier analysis, log-rank test, and uni- and multivariate Cox regression analysis. High expression of EGFR, EGFRvIII, and AREG was detected in 73%, 17%, and 45% of SCCHN cases, respectively. Expression levels of EGFR had no impact on PFS or OS. High expression levels of EGFRvIII were significantly associated with reduced DCR and shortened PFS (HR: 3.3, P = 0.005) but not with OS. Patients with high AREG expression in tumor cells had significantly shortened OS (HR: 2.2, P = 0.002) and PFS (HR 2.2, P = 0.019) compared with patients with low expression score. Multivariate Cox analysis revealed an independent association of AREG and EGFRvIII with PFS but only AREG was an independent prognosticator of OS. High EGFRvIII and AREG expression levels identify SCCHN patients who are less likely to benefit from combination treatment with cetuximab and docetaxel.

Genetic variants of the p53 and p73 genes jointly increase risk of second primary malignancies in patients after index squamous cell carcinoma of the head and neck

Because of the structural and biochemical similarities between the antitumor p53 and p73 proteins, the authors hypothesized that individuals who carry high-risk genotypes of p53 codon 72 and p73 G4C14-to-A4T14 polymorphisms have a higher risk of developing second primary malignancy (SPM) after index squamous cell carcinoma of the head and neck (SCCHN). A cohort of 1269 patients with index cases of SCCHN was recruited between May 1995 and January 2007 at The University of Texas MD Anderson Cancer Center and followed for SPM development. Patients were genotyped for p53 codon 72 and p73 G4C14-to-A4T14 polymorphisms. A log-rank test and Cox proportional hazard models were used to compare SPM-free survival and SPM risk among different risk groups with the combined risk genotypes of the 2 polymorphisms. The data demonstrated that patients with p53 WP + PP and p73 GC/GC genotypes had a worse SPM-free survival and an increased SPM risk compared with the corresponding p53 WW and p73 GC/AT + AT/AT genotypes. After combining the 2 polymorphisms, a borderline significantly or significantly reduced SPM-free survival and increased SPM risk were observed in the medium-risk group (p53 WW and p73 GC/GC or p53 P carriers and p73 AT carriers) and high-risk group (p53 P carriers and p73 GC/GC) compared with low-risk group (p53 WW and p73 AT carriers), respectively. The results suggest an increased risk of SPM after index SCCHN with both p53 and p73 polymorphisms individually and in combination.

Alteration of microRNA profiles in squamous cell carcinoma of the head and neck cell lines by human papillomavirus

Human papillomavirus (HPV)-positive cases of squamous cell carcinoma of the head and neck (SCCHN) have a much better disease outcome compared to SCCHN cases lacking HPV. Differences in microRNA (miRNA) expression may affect their clinical outcomes. The miRNA expression was studied using microarrays and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) in HPV-16-positive and HPV-negative SCCHN cell lines. The role of HPV-16 E6 and E7 oncogenes in altering miRNA expression was investigated using human foreskin keratinocytes (HFKs). The miRNAs miR-363, miR-33, and miR-497 were upregulated, whereas miR-155, miR-181a, miR-181b, miR-29a, miR-218, miR-222, miR-221, and miR-142-5p were downregulated in HPV-positive cells compared to both HPV-negative SCCHN and normal oral keratinocytes. HPV-16 E6 oncogene altered miRNA expression in HFKs and in an HPV-16-positive cell line with E6 knockdown using siRNA. miRNAs differentially expressed in the presence of HPV-16 may provide biomarkers for SCCHN and identify cellular pathways targeted by this virus.

Genetic variations in TERT-CLPTM1L genes and risk of squamous cell carcinoma of the head and neck

Single-nucleotide polymorphisms (SNPs) of TERT-rs2736098 (C > T) and CLPTM1L-rs401681(C > T) at the 5p15.33 locus are significantly associated with cancer risk as reported in genome-wide association studies (GWAS), but there are no reported studies for squamous cell carcinoma of the head and neck (SCCHN). In a case-control study of 1079 SCCHN cases and 1115 cancer-free controls of non-Hispanic whites who were frequency matched by age and sex, we genotyped for these two SNPs and assessed their associations with SCCHN risk. Compared with the CC genotypes of each polymorphism, the associations of a slightly reduced risk of SCCHN with the variant genotypes of CT + TT of both polymorphisms were approaching statistical significance [Odds ratio (OR) = 0.90, 95% confidence interval (CI) = 0.76-1.08 for TERT-rs2736098 and OR = 0.86, 95% CI = 0.71-1.04 for CLPTM1L-rs401681, respectively]. When the two SNPs were combined, the variant genotypes of the two SNPs were significantly associated a moderately reduced risk of SCCHN (OR = 0.82, 95% CI = 0.67-0.99), and the number of variant genotypes was associated with a significantly reduced risk in a dose-response manner (P = 0.028). Furthermore, the reduced risk was more pronounced in ever smokers, ever drinkers and patients with oropharyngeal cancer. Our results suggested that these two SNPs at the 5p15.33 locus may be associated with a reduced risk of SCCHN, particularly for their combined effect. Although we added additional evidence for the association of the two SNPs with cancer risk as reported in GWAS, additional studies are needed to replicate our findings.

Genetic variants in selected pre‐microRNA genes and the risk of squamous cell carcinoma of the head and neck

Single nucleotide polymorphisms (SNPs) in microRNAs (miRNAs) may alter the processing, transcription, and expression of miRNAs and, thus, may contribute to cancer development. The authors hypothesized that common polymorphisms in pre-miRNAs are associated individually and (more likely) collectively with the risk of squamous cell carcinoma of the head and neck (SCCHN). The authors genotyped 4 common polymorphisms in pre-miRNAs: Homo sapiens miRNA 146a (hsa-mir-146a) (reference SNP 2910164 [rs2910164]; guanine to cytosine [G→C]), hsa-mir-149 (rs2292832; guanine to thymine [G→T]), hsa-mir-196a2 (rs11614913; C→T), and hsa-mir-499 (rs3746444; adenine to guanine [A→G]) in 1109 patients with SCCHN (cases) and in 1130 cancer-free patients (controls) in a non-Hispanic white population that was frequency-matched by age and sex. Univariate and multivariate logistic regression models were used to calculate crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Of the 4 SNPs that were studied, the hsa-mir-499 AG and GG genotypes were associated with a reduced risk of SCCHN (OR, 0.83; 95% CI, 0.69-0.99). When the 4 SNPs were combined according to putative risk genotype, the number of observed risk genotypes was associated with an increased risk of SCCHN in a dose-response manner with ORs of 1.0, 1.20, and 1.40 for individuals who had 0 or 1 risk genotypes, 2 or 3 risk genotypes, and 4 risk genotypes, respectively (P(trend) = .037). Specifically, the risk was 1.23-fold (95% CI, 0.98-fold to 1.56-fold) for individuals with 2 to 4 risk genotypes and 1.40-fold (95% CI, 1.02-fold to 1.92-fold) for individuals who had 4 risk genotypes compared with individuals who had 0 or 1 risk genotypes. This risk was more pronounced in men and in patients with oropharyngeal cancer. The combined risk genotypes of 4 common SNPs in pre-miRNAs were associated significantly with a moderately increased risk of SCCHN. Larger studies are needed to validate the current findings.

Potentially Functional Single Nucleotide Polymorphisms in the Core Nucleotide Excision Repair Genes and Risk of Squamous Cell Carcinoma of the Head and Neck

Susceptibility to cancer has been associated with DNA repair capacity, a global reflection of all functional variants, most of which are relatively rare. Among the 1,098 single nucleotide polymorphisms (SNP) identified in the eight core nucleotide excision repair genes, only a few are common nonsynonymous or regulatory SNPs that are potentially functional. We tested the hypothesis that seven selected common nonsynonymous and regulatory variants in the nucleotide excision repair core genes are associated with risk of squamous cell carcinoma of the head and neck (SCCHN) in a hospital-based, case-control study of 829 SCCHN cases and 854 cancer-free controls. Assuming a recessive genetic model, we found that only carriers of the XPC 499Val/Val genotype had a significantly increased SCCHN risk (adjusted odds ratio, 1.65; 95% confidence interval, 1.16-2.36). In analysis of the joint effects, the number of observed risk genotypes was associated with SCCHN risk in a dose-response manner (P for trend = 0.017) and those who carried four or more risk genotypes exhibited a borderline significant 1.23-fold increased SCCHN risk (adjusted odds ratio, 1.23; 95% confidence interval, 0.99-1.53). In the stratified analysis, the dichotomized combined effect of the seven SNPs was slightly more evident among older subjects, women, and laryngeal cancer. These findings suggest that these potentially functional SNPs may collectively contribute to susceptibility to SCCHN. These findings need to be validated in larger, independent studies.

CYP1A1, CYP2E1, GSTM1, GSTT1, EPHX1 exons 3 and 4, and NAT2 polymorphisms, smoking, consumption of alcohol and fruit and vegetables and risk of head and neck cancer

As risk-modifiers of alcohol and tobacco effects, metabolic genes polymorphisms were investigated as susceptibility candidates for squamous cell carcinoma of the head and neck (SCCHN). A total of 210 cases and 245 hospital controls, age and gender matched, were genotyped for CYP1A1, CYP2E1, GSTM1, GSTT1, EPHX1 exons 3 and 4, and NAT2 polymorphisms. A measurement of the biological interaction among two risk factors was estimated by the attributable proportion (AP) due to interaction and its 95% confidence interval (CI). SCCHN risk was associated with high-levels of alcohol intake [OR = 3.50 (95%CI: 1.93-6.35) and OR = 6.47 (95%CI: 2.92-14.35) for 19-30 g/day and >30 g/day, respectively], cigarette smoking [OR = 3.47 (95%CI: 1.88-6.41) and OR = 7.65 (95%CI: 4.20-13.90) for 1-25 and >25 pack-years of smoking, respectively] and low-fruit and vegetables consumption (OR = 2.45; 95%CI: 1.53-3.92). No differences were observed for the genotypes or haplotypes distributions among cases and controls, and no biological interaction emerged from gene-gene and gene-environment interaction analyses. An attributable proportion (AP) due to biological interaction of 0.65 (95%CI: 0.40-0.90) was detected for heavy drinkers with a low intake of fruit and vegetables, and an AP of 0.40 (95%CI: 0.10-0.72) resulted forever smokers with low fruit and vegetables consumption. Even in presence of high alcohol consumption or cigarette smoking, a high intake of fruit and vegetables might prevent the development of around one quarter of SCCHN cases. The lack of interaction between the studied polymorphisms and the environmental exposures suggests that chronic consumption of tobacco and alcohol overwhelm enzyme defences, irrespective of genotype.

Response of Some Head and Neck Cancers to Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors May Be Linked to Mutation ofERBB2rather thanEGFR

Small-molecule tyrosine kinase inhibitors (TKI) of the epidermal growth factor receptor (EGFR) have shown modest yet reproducible response rates in patients with squamous cell carcinoma of the head and neck (SCCHN). Somatic mutations in EGFR have recently been shown to be predictive of a clinical response in patients with non-small cell lung cancer (NSCLC) treated with these inhibitors. The objective of this study was to determine if such mutations, or recently reported mutations in ERBB2, also underlie EGFR-TKI responsiveness in SCCHN patients. We sequenced the kinase domain of EGFR and exon 20 of ERBB2 in tumor specimens from eight responsive patients. In addition, mutational analysis was done on tumor specimens from nine gefitinib nonresponders and 65 unselected cases of SCCHN. None of eight TKI-responsive specimens had mutations within the kinase domain of EGFR. EGFR amplification was also not associated with drug responsiveness. However, a single responsive case had a somatic missense mutation within exon 20 of ERBB2. Our data indicate that unlike NSCLC, EGFR kinase mutations are rare in unselected cases of SCCHN within the United States and are not linked to gefitinib or erlotinib responses in SCCHN. Alternative mechanisms, including ERBB2 mutations, may underlie responsiveness in this tumor type.