Is MDM2 SNP309 Variation a Risk Factor for Head and Neck Carcinoma?: An Updated Meta-Analysis Based on 11,552 Individuals

Epidemiology of nasopharyngeal carcinoma: current insights and future outlook

Nasopharyngeal carcinoma (NPC) is characterised by its remarkable geographical and ethnic distribution. The interplay between genetic susceptibility, environmental exposures, and Epstein-Barr virus (EBV) infections is indicated in the development of NPC. Exposure to tobacco smoking, dietary factors, and inhalants has been associated with the risk of NPC. Genetic association studies have revealed NPC-associated susceptibility loci, including genes involved in immune responses, xenobiotic metabolism, genome maintenance, and cell cycle regulation. EBV exposure timing and strain variation might play a role in its carcinogenicity, although further investigations are required. Other factors including medical history and oral hygiene have been implicated in NPC. Prevention strategies, including primary prevention and secondary prevention through early detection, are vital in reducing mortality and morbidity of NPC. The current review discusses the global and regional distribution of NPC incidences, the risk factors associated with NPC, and the public health implications of these insights. Future investigations should consider international, large-scale prospective studies to elucidate the mechanisms underlying NPC pathogenesis and develop individualized interventions for NPC.

Major Molecular Signaling Pathways in Oral Cancer Associated With Therapeutic Resistance

Oral cancer is a sub-category of head and neck cancers that primarily initiates in the oral cavity. The primary treatment option for oral cancer remains surgery but it is associated with massive disfigurement, inability to carry out normal oral functions, psycho-social stress and exhaustive rehabilitation. Other treatment options such as chemotherapy and radiotherapy have their own limitations in terms of toxicity, intolerance and therapeutic resistance. Immunological treatments to enhance the body's ability to recognize cancer tissue as a foreign entity are also being used but they are new and underdeveloped. Although substantial progress has been made in the treatment of oral cancer, its complex heterogeneous nature still needs to be explored, to elucidate the molecular basis for developing resistance to therapeutic agents and how to overcome it, with the aim of improving the chances of patients' survival and their quality of life. This review provides an overview of up-to-date information on the complex role of the major molecules and associated signaling, epigenetic changes, DNA damage repair systems, cancer stem cells and micro RNAs in the development of therapeutic resistance and treatment failure in oral cancer. We have also summarized the current strategies being developed to overcome these therapeutic challenges. This review will help not only researchers but also oral oncologists in the management of the disease and in developing new therapeutic modalities.

Combined Effect of HPV and Several Gene SNPs in Laryngeal Cancer

Background and objectives: Laryngeal squamous cell carcinoma (LSCC) is one of the most common head and neck tumors. The molecular mechanism of LSCC remains unclear. The aim of this study was to evaluate the prevalence of Human papillomavirus (HPV) and single nucleotide polymorphisms (SNPs) of TP53, MDM2, MDM4, MTHFR, CASP8, and CCR5 genes in LSCC, and to assess their correlations with patient survival. Materials and Methods: 49 LSCC patients were enrolled in this study. PCR and qRT-PCR were used to detect, identify, and quantify HPV. SNPs were genotyped using PCR and PCR-RFLP. Results: By analyzing the interactions of the SNPs of the genes with clinical parameters, the majority of patients with lymph node status (N1,2) were identified as carriers of MDM2T/G, CASP8ins/del, CCR5wt/wt SNP. Cluster analysis showed that patients with MDM2T/T SNP survive longer than patients identified as CASP8ins/ins, MTHFRC/C, and MDM4A/A variant carriers; meanwhile, LSCC patients with MDM2T/T polymorphic variant had the best survival. Multivariate analysis showed that HPV-positive patients without metastasis in regional lymph nodes (N0) and harboring CASP8ins/del variant had the best survival. Meanwhile, HPV-negative patients with identified metastasis in lymph nodes (N1 and N2) and CASP8ins/del variant had poor survival. Conclusions: This finding suggests patients survival prognosis and tumor behavior are different according HPV status, SNP variants, and clinical characteristics of the LSCC.