TREATMENT OF HEAD AND NECK SQUAMOUS CELL CARCINOMA ACCORDING ON THE SPECIFIC MOLECULAR FEATURES OF THE TUMOR (A LITERATURE REVIEW)

Abstract

Despite the achieved progress in radiotherapy, chemotherapy, and surgery, head and neck squamous cell carcinoma (HNSCC) still remains the sixth most common cause of death from cancer worldwide. The division of HNSCC into 2 large groups with different survival rates is a significant achievement made during the last decades in cancer research and treatment of head and neck cancer. In 45 % – 90 % of cases, oropharyngeal squamous cell carcinoma is presumably associated with human papillomavirus (HPV). A recent whole-exome sequencing study on HNSCC helped to develop new principles of treatment that will allow to increase the effectiveness of conventional therapy. The study demonstrated that inactivating mutations in the p53 gene trigger carcinogenesis. The majority of tumors have such mutations that inactivate the p53 tumor suppressor gene. According to the results of sequencing, HPV-positive and HPV-negative tumors have completely different mutation profiles. Intratumoral heterogeneity should be taken into account when implementing new treatment approaches. We present an overview of studies published between 1989 and 2014. Current review briefly describes molecular mechanisms of carcinogenesis in HNSCC in the light of genetic and biochemical features of the tumor, paying particular attention to the most significant scientific achievements in this field. Moreover, we outline the advancements of wholeexome sequencing in HNSCC and give an overview of recent studies devoted to new therapeutic approaches. The process of carcinogenesis in HNSCC is often initiated by tumor suppressors. In this case, the development of target-based drugs is problematic. Target therapy focused on the ways of tumor growth suppression is a much more serious challenge than inhibition of oncogenic signals, because it requires reactivation of tumor suppressors and restoration of their functions, which is more difficult than conventional chemical and biological blockage. Poor survival of patients with HNSCC, which is usually associated with a small size of recurrent tumors, their latent growth, and localization in various anatomical areas, shows that there is an urgent need for developing new therapeutic approaches for the disease. The study was aimed to analyze specific molecular features of head and neck tumors and to explore the opportunities of providing personalized care for these patients.