Hakan Avci

A Strong Relationship Between Oral Squamous Cell Carcinoma and DNA Repair Genes

Single nucleotide polymorphisms of DNA repair genes alter protein function and modulate DNA repair efficiency in various cancers. The X-ray repair cross-complementing group (XRCC) is responsible for the repair of DNA base damage and single-strand breaks. The aim of our study was to investigate the association of XRCC1 Arg399Gln and XRCC3 Thr241Met polymorphisms with the susceptibility to develop oral squamous cell carcinoma (OSCC) in Turkish subjects. One hundred eleven patients with OSCC and 148 healthy controls were recruited for the study. Genetic analysis was performed using polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). We found that the XRCC1 Arg399Gln Gln/Gln genotype and Gln allele were risk factors for OSCC. Also, Arg/Arg genotype and Arg allele had protective effects against OSCC. Relative to XRCC3 Thr241Met polymorphism, carrying homozygote variants (Thr/Thr and Met/Met) was related with elevated OSCC risk. However, the heterozygote genotype and Thr allele variants were shown to be protective against OSCC. We suggest that XRCC1 Arg399Gln Gln/Gln genotype, Gln allele, and homozygote variants of XRCC3 Thr241Met polymorphism may be a risk factor for predisposition of OSCC in Turkish. In addition, XRCC3 Thr241Met genotype could be associated with tumor size and level of daily smoking.

Comprehensive analysis of parotid mass: A retrospective study of 369 cases

OBJECTIVEnTo present the results of patients who underwent superficial or total parotidectomy because of parotid gland tumors in our tertiary care clinic.nnnMETHODSnThe data of 362 patients who underwent parotid surgery from January 2008 to November 2015 were collected and analyzed in demographic, histopathological features, and complications.nnnRESULTSnThree hundred sixty-nine cases (performed in 359 patients) were analyzed and we assessed complications of parotid surgery such as transient or permanent facial paralysis and Freys syndrome. Pleomorphic adenomas and Warthins tumors consisted 74% of all parotid gland tumors. These tumors were generally located in the superficial lobe and tail of the parotid gland (81%). Also, tumor size in the positive surgical margin group was larger than in the negative surgical margin group (p=0.012).nnnCONCLUSIONSnMost of parotid gland tumors are benign. However, the frequency of malignancy increases in deep lobe of parotid gland. High grade malignant tumors have more tendency to have positive surgical margin during surgery, and facial paresis preoperatively.

Impact of Routine Plain X-ray on Postoperative Management in Cochlear Implantation

OBJECTIVESnTo determine the benefit of a routine plain radiography (X-ray) for confirming the optimal electrode position in cochlear implant surgery.nnnMATERIALS AND METHODSnIn total, 245 patients (135 males and 111 females) who underwent cochlear implantation in a single tertiary referral center were included in this study. Postoperative plain X-ray findings and electrophysiological tests were retrospectively analyzed.nnnRESULTSnThe mean age was 11.4±14.6 years (range, 1-70 years). Overall, 196 (80%) patients were pediatric patients (age, <18 years) and 49 (20%) were adults (age, >18 years). The mean rotation of electrode arrays was 1.03±0.17 turns. The plain X-ray revealed that electrode misplacement was present in 5 patients (2%); incomplete insertion in 3 patients, and tip rollover and electrode migration in 1 patient each. A revision was performed for the last patient who had an extracochlear electrode position in the plain X-ray.nnnCONCLUSIONSnPostoperative imaging is mostly used to confirm the electrode array position after cochlear implant surgery. In addition, intraoperative evaluations have low positive predictive value and sensitivity. Thus, this study revealed that postoperative radiological imaging should be considered even when all intraoperative electrophysiological measures and surgical reports are normal.

Integrative analysis of mRNA and microRNA expression profiles in laryngeal squamous cell carcinoma: EKMEKCI et al.

Larynx cancer is a therapeutically challenging disease. Rapidly evolving experimentally validated data have significantly improved our understanding of the complex role of numerous RNA, DNA, and proteins that play a role in the development and progression of cancer. Based on the insights from approximately two decades of research, it seems clear that microRNAs (miRNAs) have revolutionized our concepts related to the main role of noncoding RNAs in different cancers’ progression, development, and metastasis. Mechanistically, miRNAs have been reported to regulate different RNAs and finally protein‐coding genes. The expression profiling of miRNAs and messenger RNA (mRNAs) was conducted for a deeper analysis of the miRNAs and mRNAs which play an essential role in larynx cancer. Downregulation or upregulation over twofolds in the miRNAs was considered to be significant, and that of sixfolds or below was considered to be significant for the mRNAs. In accordance with this approach, the expression levels of 43 miRNAs were increased in this study, whereas the expression levels of 129 were decreased. Accordingly, all the genomic expression studies provided evidence of upregulation of 97 genes, whereas 128 genes were found to be downregulated. Among these miRNAs, hsa‐miR‐20a‐3p and hsa‐miR‐1972 were noted to be important in the etiology of larynx cancer.

Is Human Oxoguanine Glycosylase 1 Genetic Variant Successful Even on Oral Squamous Cell Carcinoma

Background: Oral squamous cell carcinoma (OSCC) is one of the most widespread cancer types that arise from different sites of oral cavity and has a 5-year survival rate. This study is aimed at investigating the human oxoguanine glycosylase 1 (hOGG1)-Ser326Cys and APE-Asp148Glu polymorphisms of DNA repair genes in OSCC. Materials and Methods: We investigated the hOGG1-Ser326Cys and APE-Asp148Glu polymorphisms of DNA repair genes in the oral cavity. Genotyping was conducted using polymerase chain reaction-restriction fragment length polymorphism analysis based on 132 patients who were diagnosed as having OSCC and 160 healthy subjects. Results: Individuals with the genotype hOGG1-Ser326Cys, Cys allele carriers, were found significantly more frequently in the patient group compared to the control group as increase in risk (p < 0.001). Furthermore, it was observed that there were significantly more individuals with the Ser allele in the control group (p < 0.001). Individuals with genotype APE-Asp148Glu were not statistically significant; however, they were still more in the control group and provided protection against the disease. Conclusion: Our findings showed that hOGG1-Ser326Cys Cys allele is statistically important and relevant with respect to the development of oral squamous cancer. In view of our results, further studies including expression levels are required in which hOGG1-Ser326Cys should be investigated as molecular biomarkers for the early prediction of squamous cell carcinoma.

Surgical Success of Tympanoplasty Using Composite Tragal Cartilage in Chronic Otitis Media

Abstract This study aims to investigate the preoperative, postoperative airway hearing threshold levels, and perforation closure rates in patients who underwent primary tragal cartilage tympanoplasty. One hundred seventy-one patients who had chronic otitis media without cholesteatoma underwent primary tragal cartilage tympanoplasty with endaural approach by using underlay technique. Preoperative and postoperative airway hearing threshold levels at 500, 1000, 2000, 4000u200aHz frequencies in 8 to 99 months’ follow-up were found and compared with each other. Postoperative perforation closure rates were also investigated. At 500u200aHz in 112 patients, at 1000u200aHz in 106 patients, at 2000u200aHz in 96 patients, and at 4000u200aHz in 80 patients, more than 9.5u200adB airway hearing gain was determined. The authors found their postoperative perforation closure rate as 84.8%. In conclusion, tragal cartilage tympanoplasty may be chosen as the primary operation technique in primary chronic otitis media patients and by this technique perforation closure rates are also acceptable in addition to satisfactory hearing gain.

Novel pathogenic variants underlie SLC26A4-related hearing loss in a multiethnic cohort

OBJECTIVESnThe genetics of sensorineural hearing loss is characterized by a high degree of heterogeneity. Despite this heterogeneity, DNA variants found within SLC26A4 have been reported to be the second most common contributor after those of GJB2 in many populations.nnnMETHODSnWhole exome sequencing and/or Sanger sequencing of SLC26A4 in 117 individuals with sensorineural hearing loss with or without inner ear anomalies but not with goiter from Turkey, Iran, and Mexico were performed.nnnRESULTSnWe identified 27 unique SLC26A4 variants in 31 probands. The variants c.1673Axa0>xa0G (p.N558S), c.1708-1Gxa0>xa0A, c.1952Cxa0>xa0T (p.P651L), and c.2090-1Gxa0>xa0A have not been previously reported. The p.N558S variant was detected in two unrelated Mexican families.nnnCONCLUSIONnA range of SLC26A4 variants without a common recurrent mutation underlies SLC26A4-related hearing loss in Turkey, Iran, and Mexico.

Could the ENPP1 p.D85H mutation be associated with hypophosphatemic rickets

Objective: A 35-year-old Turkish male patient was referred to us with a year-long history of joint paint and congenital hearing loss. Family history revealed more family members with hearing loss without paraneoplastic syndrome. These findings led us to investigate the genetic alterations associated with familial hypophosphatemia, which revealed an ENPP1 mutation. Methods: Serum samples were obtained after 12-hour fasting. The mutation analysis was performed using previously described primers. Total RNA was isolated from blood samples using Qiagen Total RNA extraction mini kit. cDNA samples were amplified using polymerase chain reaction (PCR), and these PCR products were purified using commercial kits. Following amplification and purification, the PCR products were sequenced. Results: The patient was found to have hypophosphatemia, a high level of PTH, and elevated plasma alkaline phosphatase. Sequencing results revealed an ENPP1 p.D85H mutation. Conclusion: We present the identification of an inactivating mutation in the ectonucleotide pyrophosphatase/phosphodiesterase-1. The substituted amino acid residue is highly conserved in ENPP1. At present, we have no further explanation, but our results suggest that ENPP1 p.D85H mutation may be associated with hypophosphatemic rickets accompanied by hearing loss.

Medicolegal aspects of rhinology practice

OBJECTIVEnTo investigate rhinology-related malpractice claims with the aim of optimising safe practice.nnnMETHODSnThe database of the National Institute of Forensic Medicine was reviewed. In total, 241 otorhinolaryngology malpractice case reports dating from 2005 to 2012 were evaluated, and 83 malpractice cases related to rhinology treatments were separated.nnnRESULTSnThere was no significant difference between the number of male (n = 42) and female (n = 41) claimants. The mean patient age was 32.07 ± 10.53 years (range, 10-75 years). Seventy-nine cases involved surgical treatment in rhinology. The most common complaints were: unsatisfactory cosmetic results (n = 30), optic nerve injury (n = 10), septal perforation (n = 9) and intracranial penetration (n = 4). Malpractice was detected in 21 cases (25.3 per cent). No delinquency was found in 62 cases (74.7 per cent).nnnCONCLUSIONnPhysicians should be aware of legal consequences related to rhinology practice. Further study is needed on this topic, as well as interdisciplinary collaboration, to ensure best practices and to avoid litigation.