The role of the WNT signaling pathway in the maxillary sinus squamous cell carcinoma.

Paranasal sinus tumors are a rare type of cancer. Most of these tumors are of epithelial origin and 80% of them are maxillary sinus squamous cell carcinoma. The WNT signaling pathway is an essential embryonic regulatory pathway known to play an important role in many cancers, including head and neck cancers. However, the effect of this pathway in maxillary sinus tumors has not been studied before. The aim of the study was to determine the changes in the regulatory genes of the WNT signaling pathway in maxillary sinus tumors. For this purpose, total RNA was isolated from the pathological preparations of 85 patients who had previously been operated on for squamous cell maxillary sinus tumor, and gene expression changes were evaluated by real-time RT-qPCR. The interactions among proteins encoded by genes, whose expression levels were found to be decreased and increased, were determined by protein-protein interaction (PPI) network analysis using string database, and signaling pathways that they are involved in were examined by Reactome database. A significant decrease in the expression of 28 genes compared to the control (fold change < 2.00 and p-value < 0.05) and a significant increase in the expression of 23 genes (fold change < 2.00 and p-value < 0.05) were detected. According to in silico analysis results, Signal Transduction (REACTOME:R-HSA-162582) and Signaling by WNT (REACTOME:R-HSA-195721) pathways were determined as most regulated pathways and FZD4-LRP5 and BCL9-CTNNB1 were determined as the strongest interactions. The current study contributes to illuminating the genetic regulation of maxillary sinus carcinoma in which genetic knowledge is limited. Our findings take attention to the dysregulations of the WNT signaling pathway that may support maxillary sinus carcinogenesis. The results will pave the way for further studies that investigate the therapy target potential of the WNT signaling pathway in this rare cancer.

PI3K/AKT/mTOR pathway and autophagy regulator genes in paranasal squamous cell carcinoma metastasis.

Although there are many studies on the role of PI3K/AKT/mTOR pathway and autophagy genes in the mechanism of head and neck cancer formation and prognostic significance, there is no study investigating the role of the genes in paranasal sinus carcinomas. The aim of the study was to assess the role of the PI3K/AKT/mTOR pathway and autophagy related gene expression changes in squamous cell carcinoma of paranasal sinuses with and without neck metastasis. Eight paranasal squamous cell carcinoma patients (five without and three with neck metastasis) were included. Tissues were obtained during the surgery. Total RNA was isolated from the tissues and cDNA synthesis was performed. Expression levels of the genes were determined using qRT-PCR method. The results were evaluated using the 2-∆∆Ct method, and fold changes of the gene expression levels in primary tumor and neck metastasis tissues were calculated according to the normal tissue. Expression levels of both PI3K/AKT/mTOR pathway and positive regulators of autophagy were significantly increased in metastasis-related two groups, especially in neck metastasis tissues. The increase in PI3K/AKT/mTOR pathway and autophagy related gene expression levels may support the metastatic character in paranasal squamous cell carcinomas. This is the first study to assess autophagy related genes in paranasal sinus cancer at transcriptome-level. Support of the transcriptome-level findings by the further protein analyses will contribute to the illumination of the rare paranasal sinus cancer molecular biology.

The Effect of Endoscopic Endonasal Transsphenoidal Skull Base Surgery on Cochlear Function.

Endoscopic transsphenoidal skull base surgery (ETSS) has become a standard approach in the treatment of sellar and clival lesions, such as pituitary adenoma and chordoma. Due to the close proximity of the clivus and the sella turcica to the inner ear, it is thought that bone drilling in the surgery may have effects on hearing. The aim of this study was to assess the effect of bone drilling in ETSS procedure on cochlear function. This study was performed on 18 patients who underwent ETSS procedure between December 2016 and May 2017. The study was designed as a prospective study. All of the data were prospectively collected. These included demographic data, date of surgery, type of surgery, preoperative pure-tone audiometry, and preoperative and postoperative distortion product otoacoustic emission (DPOAE) measurements. Of the DPOAE measurements of the patients who were operated for pituitary adenoma, there was a statistically significant difference between the signal-to-noise ratio (SNR) measurements at 0.5, 1, 2 and 4 kHz ( p < 0.05). Additionally, there were no significant differences in preoperative and postoperative SNR measurements of six patients who were selected for clivus chordoma. When the preoperative and postoperative tonal audiometric tests of the patients were compared, no statistically significant difference was found ( p > 0.05). In conclusion, it is found that bone drilling in ETSS procedure has a negative effect on cochlear function in the early period. This is the first study to evaluate the degree of noise-induced cochlear damage in patients who were gone under ETSS procedure.

Objective Assessment of Nose Tip Light Reflections in Rhinoplasty.

PURPOSE: To assess the objective and subjective analysis of facet and infratip lobule in postoperative digital pictures of rhinoplasty patients and compare them with the people with good-looking noses. With the help of simple software that measures the brightness of the pixels, we investigated the relation between light reflections and patient satisfaction. METHODS: egardless of the technique, forty patients who underwent external open approach rhinoplasty were selected randomly. Twenty participants with a good-looking nose without operation history were selected as the control group. Digital Color Meter® in MacOS X® was used for measuring the brightness of the facets and infratip lobule. As a subjective outcome measure, the visual analog scale (VAS) was used and compared with brightness ratios. RESULTS: The mean brightness ratios and VAS of operated noses were statistically low from the control group. There was a significant positive correlation between brightness ratios and VAS in all groups. CONCLUSION: Our study presents the results of a simple method of measuring the light reflections of the nose tip. Noses with a good aesthetic outcome have more symmetric and subtle facets and infratip lobule. This method was feasible, and its results were correlated with patients' aesthetic perceptions. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .