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Background: Aberrations in Wnt signaling pathway are related to the pathogenesis of head and neck carcinomas and their activation frequently results from epigenetic alterations. This study aimed to assess the frequency of the methylation of DAB2, which acts as a negative regulator of Wnt signaling, and correlate it with clinicopathological features in a group of oral cancer patients., Material and Methods: Forty nine patients with primary oral squamous cell carcinoma were enrolled in the study. DNA samples were isolated from surgical sections using phenol-chloroform extraction. Methylation-specific PCR was used to detect gene promoter methylation., Results: The analysis of the occurrence of DAB2 promoter methylation in primary oral carcinomas indicated that the gene is methylated in 70% of cases. However, no correlation was found between its methylation and TNM staging or overall survival., Conclusions: Our findings corroborate that DAB2 is a frequent target of epigenetic silencing in oral carcinomas and may be potentially used for tumor detection., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

Objectives: Aberrations in Wnt and Shh signaling pathways are related to the pathogenesis of head and neck carcinomas, and their activation frequently results from epigenetic alterations. This study aimed to assess the frequency of methylation of negative regulators of Wnt signaling: CXXC4, DACT2, HDPR1, and FBXW11 and Shh signaling: HHIP, PTCH1, SUFU, ZIC1, and ZIC4 and correlate it with clinicopathological features in this group of patients., Materials and Methods: Methylation-specific PCR was used to detect gene promoter methylation, and real-time PCR was used to assess gene expression level., Results: The analysis of the occurrence of gene promoter methylation in head and neck carcinoma cell lines indicated that CXXC4, DACT2, HHIP, ZIC1, and ZIC4 are methylated in these tumors. These genes were further analyzed in tumor sections from oral and laryngeal cancer patients. Gene methylation rate was higher in laryngeal tumors. The methylation index in tumor samples correlated with the overall survival in a subgroup of oral cancer patients who died of the disease. Moreover, ZIC4 methylation correlated with lymph node involvement in oral cancer patients., Conclusions: Our findings corroborate that the activation of Wnt signaling in head and neck squamous cell carcinoma (HNSCC) is related to epigenetic silencing of its negative regulators. Moreover, the results indicate that the same mechanism of activation may operate in the case of Shh signaling., Clinical Relevance: The methylation of ZIC4 may be considered a new prognostic marker in oral cavity and oropharyngeal tumors. Further investigations should determine the diagnostic significance of methylation of ZIC4, HHIP, and DACT2 in head and neck carcinomas.

It was established, that HPV virus (Human Papilloma Virus) is responsible for tumor induction in some anatomical regions of head and neck, mainly in palatine tonsils. The characteristics of HPV-related tumors as well as the course of the disease are definitely different compared to tobacco-smoking related tumors; patients HPV-positve have better prognosis - less patients develops recurrences and dies from the disease. There is no full compliance about patients' characteristics, although most indications concern "young adults" with their intensive sexual life. Because the course of HPV-related tumors is milder, there is a need to distinguish the cause of disease to carry on the therapy adjusted to the causative factor. This approach might help to select HPV-negative patients with severe course of disease to apply more aggressive chemotherapy.

Aim of the Study: The evaluation of the importance of the prognostic of sentinel node biopsy in head and neck cancer with N0 neck., Material and Methods: Prospective study included 19 patients with squamous cell carcinoma of the oral cavity, pharynx and larynx without enlarged lymph nodes in ultrasound examination (N0). The study was carried out in ENT Department of Medical University in Poznań between 2001-2004. Each patient underwent lymphoscintigraphy after administration of radionuclide Technetium 99m (Nanocol). In case of detection of sentinel node, blue dye was injected into the tumour bed and dyed lymph nodes were removed. The specimens were evaluated histologically and immunohistochemically. The patients are still followed up., Results: So far 19 patients were included in our study. The tumours were classified from T1 to T4. In each case sentinel nodes were located. Metastases in removed lymphnodes were found in 5 patients. In one of them regional recidive was observed after 5 month. In the other patients no changes were found in follow up examination. In 14 cases in histological examination no metastases were found in sentinel nodes. In this group in one case local recurrence was observed and in another two lymph nodes metastases were confirmed. In patients with positive sentinel node elective neck dissection was performed. So far immunohistochemical examination has not provided us with any vital information. In no case with negative sentinel node we found micrometastases with the use of cytokeratin., Conclusions: Based on our preliminary observation of the patients we have found that there is certain correlation confirming the fact that sentinel node may be reliable for the whole neck lymphatic system. Further clinical observation are needed based on a larger number of patients and longer observation period.