What if amoxicillin/clavulanic acid reduces the cisplatin anticancer impact on oral cancer treatment?

Antibiotics-chemotherapeutics combination have become on the table for many cancer treatments. For this reason, we thought that further progress and development of studies to support chemotherapeutic approaches with the use of antibiotics may be beneficial in the clinical field. Cell lines (SCC-15, HTB-41, and MRC-5) were treated with 5-100 μM/ml concentrations of cisplatin (cisp) and amoxicillin/clavulanic acid (amx/cla) with combination (amx/cla-cisp) and alone in three different incubation periods. The all-cells viability was examined with WST-1 and apoptotic activity of the drugs were investigated via cell death ELISA assay kit. The cytotoxic impact of the 100 μM amx/cla-cisp combination was found to be reduced by up to 21.8%, which was significant given that the cytotoxic effect of only cisplatin therapy was 86.1%. Because our findings demonstrated that solo amx/cla therapy have almost no impact on proliferation or death, we focused on the amx/cla-cisp combination effect. It was found that the amx/cla-cisp combination has reduced the apoptotic fragment when comparing with the solely cisp-treated cells. Due to amx/cla-cisp combination on both cells but significantly on SCC-15 recovered the sole cisplatin effect, we believe that there might be a second thought when prescribing antibiotics while treating cancer patients. Not only the antibiotic's type but also the cancer type might interact to lessen the chemotherapeutic agent's impact which is clinically a dilemma to focus on.

Identification of copy number alternation profiles in metastatic oral squamous carcinoma patients by using microarray-based comparative genomic hybridization: A study on Turkish patients

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is a severe form of cancer affecting different anatomic sites of the oral cavity. OSCC ranks as the sixth most common cancer type with an increasing prevalence globally. However, the mechanisms of OSCC process at later stages are not well understood. In this study, we aimed to determine genetic alternations in metastatic OSCC patients to identify genomic changes occurred at metastatic phase of the disease.

MATERIAL AND METHODS

The Illumina CytoSNP-12 Array was used to determine copy number variations in OSCC cancer genome. Hybridization procedures were performed according to the manufacturer procedures (Illumina). Arrays were scanned on iScan System (Illumina). Data were analyzed using Illumina Genotyping module of Genome Studio software (version 1.2, Illumina). Multiple CNV algorithms and copy number alternations were accessed by Genome Studio. CNVs in whole genome were investigated by using a chromosomal heat map.

RESULTS

We reported that gains in 8q21.11-ter, 9p21.3, 13q14.11-ter, 13q13.3-ter and losses in 5q14.3-ter, 5q35 and 17p13.3-12 were associated with the development of OSCC. In addition, we also detected that deletion in 2q33.2-ter and 2q35-37.3 regions were also associated with OSCC metastasis process.

CONCLUSIONS

Our results were also showed that gains in 11q13.3-q13.4 and 2q13.2 chromosomal regions could promote the metastatic OSCC process. We believe that results of the study will help to find new biomarkers for diagnosis at later stage of OSCC.

The association of epidermal growth factor variant with oral squamous cell carcinoma

In this study, our aim was to investigate the epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) gene polymorphisms in oral squamous cell carcinoma (OSCC) patients and non-OSCC healthy controls. This case-control study comprised 89 OSCC and 107 healthy controls by using polymerase chain reaction (PCR) and restriction fragment length polymorphism methods, the genotypes for EGF + 61 A > G (rs4444903) and EGFR R497K (rs2227983) were analyzed. According to the EGF + 61 A > G genotype distribution, individuals with the GG genotype were more prevalent in the OSCC group when compared to the healthy controls. But the AA genotype frequency was significantly higher in the healthy control group. The frequency of G allele carriers was 2.3 times higher than A allele carriers in OSCC patients (p < .001). For the EGFR R497K genotype, there was no significant difference between the OSCC and healthy control groups. Regarding the study results, the G allele of EGF + 61 A > G polymorphism was associated with OSCC. Larger populations and functional investigations should be used to explore the nature of the interaction between EGF and OSCC.

High-risk HPV Does not Appear to be an Important Risk Factor for Sinonasal Carcinomas in Turkish Population: A Tertiary Center Experience

Background. The sinonasal tract is the second most common site of human papillomavirus (HPV)-related carcinomas in the head and neck. Published data on the association between sinonasal tumors and HPV are quite inconsistent among different regions. Material and methods. We performed high-risk HPV DNA in situ hybridization (ISH) and p16 immunohistochemistry on sinonasal carcinomas diagnosed between 2006 and 2016. Results. Of 105 sinonasal carcinomas, we found only two (2%) HPV-positive cases; both had non-keratinizing morphology and were diffusely positive for p16. By histologic type, HPV DNA positivity rate was 14% in non-keratinizing squamous cell carcinomas, and we did not detect HPV DNA in any other type of sinonasal carcinomas. Thirteen HPV-negative tumors (7 salivary gland carcinomas, 3 sinonasal undifferentiated carcinomas, 2 keratinizing squamous cell carcinomas, and 1 non-keratinizing squamous cell carcinoma) were positive for p16. In nine carcinomas arising from an underlying sinonasal papilloma, p16 and HPV DNA ISH were evaluated in both carcinoma and papilloma areas and all were negative. Follow-up information was available for 104 patients; 46 (44%) were alive and 58 (55%) died of disease. One of the two HPV-positive patients died of the disease; the other was alive at 100 months of follow-up. Conclusions. We detected a much lower percentage of HPV positivity in sinonasal carcinomas when compared to the literature. We believe that our results support various rates of HPV-related carcinomas depending on the geographic and ethnic characteristics.

Evaluation of genetic and epigenetic changes of Tumor Necrosis Factor-Alpha gene in larynx cancer

BACKGROUND

Tumor Necrosis Factor-Alpha (TNF-α) is a proinflammatory cytokine that plays a role in inflammation, which is one of the hallmarks of cancer, and its polymorphic variants have been associated with disease risk in many cancers in the literature. The aim of this study was to investigate four different polymorphic variants, differential methylation and expression status of the TNF-α gene and to determine the associations between these variants and disease risk, and to evaluate the relationship between the results and clinical parameters. We purposed to investigate the genetic and epigenetic alterations of the TNF-α gene in larynx cancer (LC).

MATERIAL AND METHODS

After isolation of DNA/RNA from whole blood, tumor and normal tissue, polymorphic variant alleles differrential expression and methylation levels were analyzed by RFLP, semiquantitative RT-PCR, and restriction enzyme digestion, respectively. TNF-α expression and methylation levels were calculated using BIO1D software. The frequencies of the variants c.-238 G>A (rs361525), c.-857 C>T (rs1799724), c.-863 C>A (rs1800630), and c.-1031 T > C (rs1799964) in the promoter region of TNF-α in LC Turkish patients and healthy individuals were examined using the De-Finetti case-control program. Haplotype frequencies and linkage disequilibrium were analyzed using the SNPStats program.

RESULTS

The frequency of genotype c.-1031 T > C was significantly lower in patients than in healthy individuals [TT vs TC: OR (%95CI) = 7.00 (1.75-27.93), p = 0.003, χ2 = 8.76]. The heterozygous variant of - 857 was associated with recurrence [T vs G: OR (%95CI) = 0.15 (0.02-0.95), p = 0.02, χ2 = 4.86]. For c.-238 G>A, c.-857 C>T, and c.-863 C>A, there was no statistically significant difference between the patient and healthy group in terms of disease risk. A significant association was found between c.-1031 T > C and disease risk of LC. Decreased expression was detected in 46% (23/50) and increased expression in 54% (27/50) of tumor tissue samples compared to the matched normal tissues of patients. Methylation-related loss of expression was detected in 53.3% (16/30) of patients.

CONCLUSION

Our study is the first investigating four different polymorphic regions of the TNF-α promoter region and the expression/methylation status of TNF-α in the same LC patient and healthy cohort. According to our results, the c.-1031 T > C variant was reported to be significantly associated with a reduced risk of LC. In addition, the TNF-α variant c. -857 C>T suggests that it may be a potential biomarker for predicting the recurrence of LC. An association between c. -857 C>T variant and methylation-based expression status was observed.

Supraclavicular artery island flap for head and neck reconstruction

BACKGROUND

The ablative surgical resection has a critical importance for achieving better oncological outcomes for patients with head and neck cancer. However, radical surgical resections reveal the reconstruction requirement of complex anatomical structures. Microvascular free flaps have been recommended as a gold standard treatment choice for head and neck reconstruction following definitive oncological surgery. The supraclavicular artery island flap (SCAIF) is a thin and reliable fasciocutaneous pedicled flap that is simple and quick to harvest.

MATERIAL AND METHODS

A total of 19 patients who underwent head and neck reconstruction with SCAIF were included in this study. The SCAIF was used for the reconstruction of oncological defects in 17 patients while it was used for the reconstruction of a skin defect on the lower face following radiotherapy in 1 patient and for cervical open wound (blast injury) closure in 1 patient.

RESULTS

There were neither intraoperative nor postoperative major complications in any patient. The SCAIF has been used successfully in 18 of 19 patients for head and neck reconstructive surgery. Partial necrosis of the skin was detected in 1 patient (5.3%) only, while a total flap failure has not occurred in any patient. The partial skin necrosis was seen in an area of 1.5 cm of the distal end of the flap and was managed conservatively with local wound care. Wound dehiscence has not appeared in the flap donor area in any patient.

CONCLUSION

The SCAIF constitutes a good alternative to free flaps, providing almost equivalent functional results and requiring less operative time and surgical effort.

Promoter region mutations of the telomerase reverse transcriptase (TERT) gene in head and neck squamous cell carcinoma

OBJECTIVE

The aim of the present study was to assess the prevalence of TERT promoter region mutations in tumor samples of patients with squamous cell carcinoma at different sites of the head and neck region and correlate it with patients' clinicopathologic data.

STUDY DESIGN

Mutations in promoter region of the TERT gene were analyzed with polymerase chain reaction-based direct sequencing method using formalin-fixed, paraffin-embedded tumor samples of 189 HNSCCs. TERT promoter region mutations were assessed in terms of age, gender, location, smoking, alcohol consumption, and overall survival.

RESULTS

TERT promoter region mutations were detected in the oral cavity (75%); larynx (8.4%), hypopharynx (16.6%), and oropharynx (0%). TERT promoter region mutations are associated with younger age and female gender and have a reverse relationship with smoking and alcohol consumption.

CONCLUSIONS

We found statistically significant higher rates of TERT promoter region mutations in tumor samples of patients with squamous cell carcinoma in the oral cavity compared with other locations in the head and neck region.

ROS related enzyme levels and its association to molecular signaling pathway in the development of head and neck cancer

Given the prevalence and annual incidence of cancer, head and neck cancer is affecting more than 600,000 people each year. In this research, it was decided to investigate that which genes are involved and how MPO, NQO1, SOD2 enzyme levels effective to develop of head and neck cancer and for the first time at the tissue level. 35 tumor tissues in all head and neck anatomy and their surrounding tissue (70 in total) were enclosed the research that received surgery. Determination of the apoptosis genes expression levels (Mtch1, Akt1, Caspase3, Caspase9, Bcl2, Mdm2, mTOR) were determined by RT-PCR techniques and the same patients' sample used for ROS associated oxidant-antioxidant system by using MPO, NQO1, SOD2 enzyme levels using ELISA method. According to statistical results, caspase 9 gene was found statistically high expressed in early stage in contrast to late stage (p=0,013). Level of SOD2, NQO1 and MPO was determined and only MPO level was found significantly important on tumor tissues p=0,008).  Specially, our findings for high expression of Cas9 on early stage were thought to be the target for treatment with its well-known initiator role of the apoptosis. Our results suggest that the higher level of MPO in tumor tissues and indicates that it has some role on pathology of head and neck cancers. We believe that, our research will lead the proposal in-vivo studies and will open new areas on therapeutic targets.

ROS related enzyme levels and its association to molecular signaling pathway in the development of head and neck cancer

Given the prevalence and annual incidence of cancer, head and neck cancer is affecting more than 600,000 people each year. In this research, it was decided to investigate that which genes are involved and how MPO, NQO1, SOD2 enzyme levels effective to develop of head and neck cancer and for the first time at the tissue level. 35 tumor tissues in all head and neck anatomy and their surrounding tissue (70 in total) were enclosed the research that received surgery. Determination of the apoptosis genes expression levels (Mtch1, Akt1, Caspase3, Caspase9, Bcl2, Mdm2, mTOR) were determined by RT-PCR techniques and the same patients' sample used for ROS associated oxidant-antioxidant system by using MPO, NQO1, SOD2 enzyme levels using ELISA method. According to statistical results, caspase 9 gene was found statistically high expressed in early stage in contrast to late stage (p=0,013). Level of SOD2, NQO1 and MPO was determined and only MPO level was found significantly important on tumor tissues p=0,008).  Specially, our findings for high expression of Cas9 on early stage were thought to be the target for treatment with its well-known initiator role of the apoptosis. Our results suggest that the higher level of MPO in tumor tissues and indicates that it has some role on pathology of head and neck cancers. We believe that, our research will lead the proposal in-vivo studies and will open new areas on therapeutic targets.

Copy number profiling of tumor suppressor genes in head and neck cancer

BACKGROUND

Sensitive and reliable new biomarkers are needed in head and neck cancer to predict the outcome and for therapy that is more effective. Copy number alterations are frequent and play a critical role in cancer.

METHODS

Copy number alterations of 24 tumor suppressor genes in head and neck cancer were analyzed simultaneously in matched tumor and normal samples from 93 patients using multiplex ligation-dependent probe amplification (MLPA).

RESULTS

Chromosomes 3p and 9p displayed the most common alterations. The gene displaying most frequent losses was the mutL homolog 1 (MLH1) gene, followed by the cyclin-dependent kinase inhibitor 2A (CDKN2A) and CDKN2B genes. A significant correlation was observed between the CDKN2A and CDKN2B genes. The tissue inhibitor of metalloproteinase (TIMP)3 gene alterations were observed in 8 tumors.

CONCLUSION

Our data confirm previous observations and suggest that losses of the MLH1 and CDKN2 genes and alterations of the TIMP3 gene play an important role in head and neck carcinogenesis. © 2016 Wiley Periodicals, Inc. Head Neck 39: 341-346, 2017.

Abstract 4443: Investigation of the promoter methylation status of the FHIT (fragile histidine triad) gene in larynx cancer

Purpose: Development of carcinoma is associated with epigenetic modifications. Methylation of CpG islands in the promoter regions can participate in gene silencing and promote tumor aggressiveness. The Fragile histidine triad (FHIT) gene, localized on chromosome 3, is a tumor suppressor gene and the abnormal methylation of FHIT. The FHIT regulates the G2/M cell cycle check point and apoptotic pathwaysin various types of cancer. Inactivation of FHIT due to methylation has been shown in breast, cervical, gastric and colon carcinomas. In our study, we evaluated the FHIT gene promoter methylation in patients with larynx carcinoma (LC).

Experimental Design: Methylation of FHIT was investigated by bisulfite modification/methylation-specific polymerase chain reaction in tumors and matched normal tissue samples from 57 Turkish patients with LC.

Results: The promoter region of the FHIT was methylated in 96.49% and 29.82% of the primary tumors and the corresponding normal tissue samples, respectively [p = 0.0001, chi-square = 14.2105, OR(95%CI) = 64.7(14.4-296.07)]. A methylation rate (less than 10%) was observed in 3.51% (2/57) and 70.18% (40/57) of tumor and normal samples, respectively. Moderate methylation levels (10-25%) were found in 3.51% (2/57) of the tumors and 1.75% (1/57) of the adjacent normal tissues. High methylation levels (&gt;25%) were observed in 92.98% (53/57) and 28.07% (16/57) in the tumor and normal tissues, respectively.

Conclusion: Methylation may play an important role in LC carcinogenesis. Although we found that there was significant association between the methylation levels of tumor and adjacent normal tissues, high methylation levels of the FHIT was observed in the tumors when compared to the levels in normal tissue. These results suggest that the methylation rates of FHIT gene may provide a suitable biomarker in LC carcinogenesis. Our study is still in progress to include a larger cohort of patients.

Citation Format: Semra Demokan, Kubra Akalin, Cansu Ozkoklesen, Murat Ulusan, Necati Enver, Nejat Dalay. Investigation of the promoter methylation status of the FHIT (fragile histidine triad) gene in larynx cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4443.

Abstract 4458: Discovery of novel epigenetic biomarkers in premalignant/malignant oral cavity lesions by methylation arrays

Purpose: The incidence of the oral squamous cell carcinoma (OSCC) is around 50% of all head and neck cancer (HNC), the sixth most common type of cancer in the world. Aberrant hyper/hypo-methylation in the promoter region of some known or putative tumor suppressor/protoonco-genes occurs frequently during the development of various cancers including OSCC. Both of genetic and environmental factors play roles in the carcinogenesis of malignant lesions. Etiological factors predisposing to OSCC are smoking, alcohol and tobacco consumption, snuffuse, viral factors, chronic irritation, iron and various vitamin deficiencies, poor oral hygiene and diseases such as syphilis. Despite the advances in cancer diagnosis and treatment, the 5-year survival rate of OSCC patients is poor and because of advanced stage of disease, it has high mortality and morbidity. Another the most important ethiological factor of OSCC is oral premalignant lesions (OPML), since OPML is related with malignant transformation. In our study, we included three different OPML associated with different risks of leading to malignancy: Oral leukoplakia has a high risk of conversion into malignancy, whereas oral lichen planus and oral lichenoid dysplasia are associated with lower risk. We aimed to investigate the epigenetic characterization of OSCC and OPML relative to the epigenetic changes in these groups.

Experimental Design: Tumor and corresponding healthy tissues from 12 and 10 Turkish patients with OPML and OSCC, respectively were collected. The samples were analyzed histopatologically and after DNA extraction and bisulfite modification, methylation patterns of the samples were investigated by using the Illumina Infinium HumanMethylation450 (450K) BeadChip array.

Results: According to our preliminary results obtained from the methylation array experiments, CpG regions in the UOX, ABCC12, FCRLB, ABL2, LGR6 and SLC22A18 genes were found unmethylated while CpGs located in YPEL-3 were highly methylated (p&lt;0.005).

Conclusion: We concluded the UOX, ABCC12, FCRLB, ABL2, LGR6, SLC22A18 and YPEL-3 may be potential biomarker candidate genes playing role in the transformation mechanism of OPML/OSCC. In the further studies, we will compare the methylation patterns between OPML subgroups to discriminate the potential candidates.

*This study was supported by the Scientific and Technological Research Council of Turkey (TUBITAK-SBAG-114S497).

Citation Format: Semra Demokan, Sevde Comert, Cansu Ozkoklesen, Murat Ulusan, Gulsum Ak, Canan Alatli, Nejat Dalay. Discovery of novel epigenetic biomarkers in premalignant/malignant oral cavity lesions by methylation arrays. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4458.

The importance of mold sensitivity in nonallergic rhinitis patients

BACKGROUND

In recent studies, local specific immunoglobulin E (sIgE) production against allergens in nasal mucosa and a positive response to a nasal allergen provocation test (NAPT) have been demonstrated in some patients initially diagnosed as nonallergic rhinitis (NAR) or idiopathic rhinitis (IR). The aim of this study was to evaluate the presence of local allergic rhinitis (LAR) in patients who experience rhinitis symptoms in indoor and outdoor moldy conditions and to investigate the role of the NAPT in diagnosis.

METHODS

A total of 40 NAR patients with a history of persistent rhinitis and who had negative skin-prick tests (SPTs) and serum sIgE levels to common aeroallergens, as well as 20 healthy subjects were included in the study. NAPTs were performed with Aspergillus fumigatus (group 1) or a mixture of Alternaria alternata and Cladosporium herbarum extracts (group 2).

RESULTS

In patient nasal lavage fluids, tryptase and mold sIgE levels were not significantly different from the control group. NAPT with Aspergillus fumigatus was positive in 8 of 12 NAR patients (66.6%) in group 1 and NAPT with the mixture of extracts was positive in 9 of 13 NAR patients (69.2%) in group 2.

CONCLUSION

This study suggests that LAR may exist in a significant number of the persistent rhinitis patients who were previously considered as NAR based on negative SPTs or serum sIgE tests. To the best of our knowledge, this is the first study evaluating a nasal local allergic response to both indoor and outdoor molds.

Abstract 1059: Analysis of promoter methylation levels of COX2 gene in Turkish patients with head and neck cancer

Purpose: Methylation of CpG islands in the promoter regions of genes plays an important role in head and neck carcinogenesis. Overexpression of COX2 gene was recorded in various types of cancer in literature. In addition, the promoter region of the COX2 gene displayed high methylation in normal colorectal tissue and normal gastric tissue samples. On the other hand, it has recently been reported in two different gastrointestinal cancer studies, that low expression of COX2 was observed in some colorectal/gastric cancers and hypermethylation/related transcriptional silencing of COX2 gene is common in colorectal cancer. There is no study investigating the COX2 methylation status on head and neck cancer (HNC) in the literature. In our study we evaluated the COX2 gene promoter methylation in patients with HNC.

Experimental Design: Methylation of the COX2 was investigated by bisulfite modification/methylation-specific polymerase chain reaction in tumors and matched normal tissue samples from 99 Turkish patients with HNC.

Results: The promoter region of the COX2 was methylated in 53.5% and 65.6% of the primary tumors and the corresponding normal tissue samples, respectively [p = 0.082, χ2 = 3.02, OR(95%CI) = 0.602 (0.34-1.06)]. Considering the methylation levels observed in our previous studies, and published data on different cancer types, methylation levels &lt;10% were considered unmethylated, whereas levels between 10% to 25% and 25% to 100% were classified as moderate and high methylation, respectively. Based on this information, methylation ratio was observed less than 10% in 46.5% and 34.3% of tumor and normal samples, respectively. The moderate methylation levels (10-25%) were found in 23.2% of the tumors and 7.1% of the adjacent normal tissues. High methylation levels (&gt;25%) were 30.3% and 58.6% in the tumor and normal tissues, respectively (p = 0.00006, χ2 = 19.24). The results were similar when a subgroup of 60 patients with larynx cancer from this cohort, were analyzed separately (p = 0.0006, χ2 = 14.87).

Conclusions: Methylation may play an important role in HNC carcinogenesis. Although we found that there was no significant association between the methylation levels of tumor and adjacent normal tissues, high methylation levels of the COX2 gene were observed (&gt;25%) in normal matched tissues when compared to the levels in HNC tumors.

Citation Format: Semra Demokan, Cansu Ozkoklesen, Zubeyde Yalniz, Necati Enver, Murat Ulusan, Nejat Dalay. Analysis of promoter methylation levels of COX2 gene in Turkish patients with head and neck cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1059. doi:10.1158/1538-7445.AM2015-1059

The Effect of Arytenoidectomy on Functional and Oncologic Results of Supracricoid Partial Laryngectomy

OBJECTIVE

The effect of arytenoid resection was investigated in patients who had undergone supracricoid partial laryngectomy (SCPL) by comparing functional and oncologic results between patients with both arytenoids preserved with those with one arytenoid resected.

METHODS

Patients were divided into 2 groups: (1) both arytenoids preserved SCPL (BASCL) cases and (2) one arytenoid preserved SCPL (OASCL). The functional outcomes of the 2 groups were compared in terms of nasogastric tube removal time, decannulation time, incidence of aspiration pneumonia, and Performance Status Scale Scores for Head and Neck Cancer Patients for the late postoperative period. Additionally, the oncologic outcomes of both groups were compared using the 5-year local control rate, overall survival, disease-specific survival, and larynx preservation rate.

RESULTS

Of the 68 patients who were enrolled in the study, 20 of them were in the OASCL group and 48 in BASCL group. There was no statistically significant difference in the early and late functional outcomes, and the oncologic outcomes were also similar.

CONCLUSION

In addition to the proven oncologic safety, arytenoid resection does not increase the functional morbidity of the SCPL.

Abstract 4400: The let-7 microRNA binding site variant in the KRAS 3′-UTR is not associated with the risk of head and neck cancer

The KRAS gene is activated by somatic mutations in many cancer types. However, KRAS mutations are relatively rare in squamous cell carcinomas. In squamous cell cancers of the head and neck (HNSCC) amplification of the KRAS gene has been shown to promote tumor growth. miRNAs are short non-coding RNAs which play an important role as regulators of gene expression. They bind to the 3′-untranslated regions (UTRs) of the mRNAs and prevent translation of their target genes. SNPs in the miRNA binding sites are associated with disease risk and prognosis. The let-7 family of miRNAs regulate multiple oncogenes including the KRAS gene and have been shown to play a critical role in different cancer types. A functional polymorphism in the KRAS gene, not included in the GWAS platforms has been identified by candidate gene approach and was found to be a genetic marker of cancer risk and increased susceptibility to the carcinogenic effects of tobacco smoke. The polymorphism is referred to as the LCS6 (let-7 complementary site 6) variant and disrupts the let-7 binding site leading to higher KRAS expression. Such an increase in KRAS expression associated with the variant allele may represent an alternative form of KRAS activation in HNSCC and could lead to impairment of the EGFR signaling. In this study we evaluated the frequency of the KRAS variant in 216 patients with head and neck cancer and 85 healthy individuals. DNA was extracted from whole blood prior to chemotherapy or radiotherapy. The variant allele was analyzed by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. Genotype and allele frequencies were evaluated using the De-Finetti case control program. 13 % of the patients were heterozygous and 3 patients (1.5 %) were homozygous for the variant allele. The polymorphism was present in heterozygous form in 12 % of the controls. No homozygous individual was detected in the control group. The frequencies of the variant allele were 92 % and 94 % in the patients and controls, respectively. Our data indicate that the KRAS let-7 LCS6 variant allele is not associated with an increased risk of HNSCC.

Citation Format: Nejat Dalay, Semra Demokan, Yusufhan Suoglu, Rasim Yilmazer, Murat Ulusan. The let-7 microRNA binding site variant in the KRAS 3′-UTR is not associated with the risk of head and neck cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4400. doi:10.1158/1538-7445.AM2014-4400

Mycobacterium Tuberculosis Infection within a Warthin Tumor: A Case Report and Literature Review

Context:

The co-existence of tuberculosis and a Warthin tumor in the parotid gland is extremely rare.

Case Report:

A 46-year-old male presented with a mass in the left parotid region of 6-month duration. The patient's history was only remarkable for a facial swelling, night sweats and a 38.5 C° fever. A 2 × 3-cm mobile, non-tender, mass with a smooth surface was palpated on left parotid tail. CT examination showed a well-defined 30 mm in diameter tumor mass in the left superficial lobe of the parotid gland. A superficial parotidectomy was performed. The final pathological diagnosis of the parotidectomy specimen was reported as a Warthin tumor and epitheloid granulomas with caseification necrosis. Purified protein derivative (PPD) was 30 mm in enduration. Two weeks after the antituberculosis treatment fever declined to normal values and night sweats decreased.

Conclusion:

Tuberculosis can also be seen in parotid tumors which can coexist or mimic pleomorphic adenoma, Warthin tumor.

Persistent cough associated with osteophyte formation and vagus nerve impingement following cervical spinal surgery: case report

Persistent cough due to irritation of the vagus nerve by osteophytes resulting from cervical spinal surgery is a very rare condition. The authors report the case of a 49-year-old woman who presented with a persistent cough subsequent to cervical spinal surgery. One year after the initial operation, the patient underwent surgery to free the larynx from the prevertebral fascia and cut the pharyngeal plexus, but her symptoms persisted. In order to control the cough, she used a soft cervical collar with padding inserted in the left side so that the larynx would be pushed to the right, a solution she discovered on her own. Without the collar, she coughed uncontrollably. A CT scan was performed and showed an osteophyte that had developed at the level of the prosthesis. Based on these findings, the authors hypothesized that the cough was caused by vagus nerve irritation due to the osteophyte. The osteophyte was resected and the vagus nerve was moved to a position anterior to the carotid artery and was isolated by means of an autogenous tensor fascia lata graft. The patient's symptom disappeared immediately after the surgery. At the most recent follow-up visit, 18 months after surgery, the patient was symptom free and was pursuing regular daily activities without using a cervical collar.

Radiation-induced osteosarcoma of the larynx: case report and literature review

Laryngeal osteosarcoma is an extremely rare disease. Only 23 cases have been published in the literature. Radiation-induced laryngeal osteosarcoma is even rarer; this is only the third such case to be reported. A 59-year-old man underwent radiotherapy for an in situ laryngeal squamous cell carcinoma at another institution. Five years later he developed a laryngeal osteosarcoma, and a total laryngectomy was performed. Although previous reports showed a poor prognosis, our patient was without disease at the 8-year follow-up. To the best of our knowledge, this is the longest disease-free follow-up to be reported in the literature. We also present a review of the world's literature.

Promoter methylation and loss of p16(INK4a) gene expression in head and neck cancer

BACKGROUND

Silencing of tumor suppressor genes plays a vital role in head and neck carcinogenesis. In this study we aimed to evaluate aberrant p16(INK4a) gene promoter methylation in patients with head and neck cancer.

METHODS

Methylation of the gene was investigated by bisulfite modification/methylation-specific polymerase chain reaction and gene expression levels were analyzed by quantitative reverse transcription-polymerase chain reaction in tumors and matched normal tissue samples from Turkish patients with head and neck cancer.

RESULTS

The promoter region of the p16(INK4a) gene was methylated in 67.5% and 28.6% of the primary tumors and the corresponding normal tissue, respectively. This difference was highly significant. In concordance, p16(INK4a) gene expression was downregulated in 67.5% of the tumor samples. Methylation and the absence of expression in the tumors were observed in 48% of the patients.

CONCLUSIONS

Our data indicate that methylation of the p16(INK4a) gene is a frequent event in primary head and neck cancer and that it plays a major role in the silencing of p16(INK4a) gene expression during tumor development.

Simultaneous methylation profiling of tumor suppressor genes in head and neck cancer

Head and neck cancer (HNC) is a common cancer, and its prognosis has not changed during the last decades. Detection of the disease at an early stage is crucial for successful treatment, as early diagnosis can significantly increase the survival rate. Methylation of tumor suppressor genes is an early event in cancer responsible for incorrect gene silencing. Since methylation changes are reversible, they also provide a promising target for therapy. So far, only individual genes have been analyzed for aberrant methylation in HNC. In this study, we analyzed the methylation status of 24 tumor suppressor genes simultaneously by methylation-specific multiplex ligation-dependent probe amplification in matched tumor and normal tissue samples from patients with HNC. CHFR, RARβ, DAPK1, and RASFF1 genes were the most frequently methylated genes in tumor tissue. Eight genes were not methylated in any sample. The methylation frequencies for individual genes ranged from 0% to 19%. Our results indicate that methylation of tumor suppressor genes is not high as previously reported by methylation-specific polymerase chain reaction and is confined to a smaller but significant fraction of the tumors. Whether this group represents a unique entity in the disease spectrum warrants further studies.

Analysis of the hMSH2 gene variants in head and neck cancer

The hMSH2 (human MutS homolog 2) gene plays a central role in DNA mismatch repair. Structural variations in the gene may lead to protein instability and deficient mismatch repair. However, the role of polymorphic variants of the hMSH2 gene have not been defined in head and neck cancer. In this study, the roles of three polymorphic variants in the functional domains of the gene were investigated in 166 patients with head and neck cancer by allele-specific PCR, electronical array addressing, and PCR/RFLP (restriction fragment length polymorphism). This is the first study to investigate the gIVS12-6T --> C polymorphism in head and neck cancer. A significant association between the CC genotype and reduced risk of disease suggests that the gIVS12-6T --> C substitution at the splice-acceptor site may affect the risk of head and neck cancer. We did not observe an association between the Asn127Ser and Gly322Asp polymorphisms and cancer risk. A possible role of the gIVS12-6T --> C substitution warrants further validation in larger cohorts because of low allele frequency.

[Value of otoacoustic emission tests in the diagnosis and follow-up of the otitis media with effusion]

OBJECTIVES

This study aimed to determine the value of otoacoustic emission tests in the diagnosis and treatment of the otitis media with effusion.

PATIENTS AND METHODS

Seventy-eight ears of 39 patients (24 males, 15 females; mean age 7.84 years; range 4 to 14 years) operated on because of serous otitis media with effusion and adenoid hypertrophy between September 2006 and May 2007 were included in the study. The medical history, otoscopic examination and audiologic tests were used in diagnosis. Otoacoustic emission tests (DPOAE and TEOAE), pure tone audiometry and tympanometry were also applied in the pre- and postoperative first month. Myringotomy and ventilation tube insertion was performed on patients with type B tympanograms.

RESULTS

In patients with type B tympanograms, pre- and postoperative audiogram values compared with pre-treatment air and bone gap values significantly decreased (p<0.01). After treatment DPOAE and TEOAE positivity compared to pretreatment values significantly increased (p<0.001). The presence of middle ear effusion affects otoacoustic emissions.

CONCLUSION

The results of this study revealed that the measurement of otoacoustic emissions may be helpful in evaluating the condition of the middle ear during the treatment. Otoacoustic emissions are easy, practical tests for the follow-up of effusional otitis media during the pre- and postoperative period. Otoacoustic emissions may give valuable information for applying ventilation tubes and help avoid unnecessary myringotomy.

Abstract 4902: Methylation profiles in head and neck cancer

Purpose: Among human malignancies, head and neck cancer (HNSCC) is the sixth most common cancer type in the world. Multiple genetic and epigenetic changes may contribute to the development of HNSCC. One of the epigenetic alterations, aberrant methylation in the promoter regions of multiple genes that lead to transcriptional silencing, has been shown in various cancer types including HNSCC. In this study we aimed to evaluate the epigenetic changes specific to HNSCC by investigating aberrant promoter hypermethylation of a panel of 24 tumor suppressor genes.

Experimental Design: We investigated methylation of the promoter regions by methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA). The methylation status of the selected genes were analyzed in 126 patients with HNSCC. Tumor and corresponding normal tissue samples were obtained during surgical resection. Probes added to the samples hybridized with their target sequence and were amplified by PCR depending on the methylation status of the target. The amplified products were detected by sequence type capillary electrophoresis. Peak sizes and areas were normalized and the relative signal peaks were compared to determine the methylation status.

Results: 18 of 24 (75 %) genes displayed methylation in the tumor samples while none of the corresponding normal tissue samples were methylated. In 67.5 % (85/126) of the tumors the promoter regions were hypermethylated in at least one of the genes. The most frequently methylated genes were RARB (retinoic acid receptor beta), CHFR (checkpoint with forkhead and ring-finger domains) and CDH13 (Cadherin 13) genes. In 50 (39.7 %) patients, methylation was observed in more than one gene.

Conclusions: Methylation of the CHFR, RARB and CDH13 gene promoters is a frequent event in HNSCC, demonstrating potential for these genes as biomarkers in detection strategies.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4902.

The effect of tumor width and depth on extracapsular lymp node metastases in tongue tumors

OBJECTIVES

In this study, we investigate the relationship between the effects of tumor width and depth with the extracapsular nodal spread (ECS) in oral tumors.

PATIENTS AND METHODS

In this study we investigate retrospectively data of 107 patients (69 males, 38 females; mean age 45 years; range 25 to 79 years) with tongue tumors, who had undergone surgery in our clinic, between 1994 and 2004. Twenty-one of them had ECS. The effects of tumor width and depth on various parameters such as nodal metastases, survival, grade and ECS are investigated.

RESULTS

It was found that tumor width and depth were the most important factors that affect ECS and logistic regression analysis point out tumor width influence more than tumor depth. Receiver operating characteristic (ROC) curve analysis shows us when tumor width exceeds 3.7 cm or tumor depth exceeds 2.4 cm, rate of ECS reaches the maximum sensitivity and specificity.

CONCLUSION

Tumor width and depth has affects on survival and prognosis but also they have significant relation with ECS.