ABSTRACT
To identify genetic alterations associated with tongue cancer recurrence in young adults, whole exome sequencing of the primary tumor, recurrence, and whole blood samples from young patients with tongue cancer was performed. A frameshift mutation in the TP53 gene was detected in the primary tumor and recurrence tumor tissue. A mutation in the EPHB6 gene was detected in the recurrence and was absent in the primary tumor. In addition, the primary tumor and recurrence tongue cancer tissue harbored amplification of the 20p13 region containing C20orf96, DEFB125, DEFB126, DEFB127, DEFB128, DEFB129, DEFB132, and ZCCHC3 genes. Thus, genetic alterations have been identified that are associated with tongue cancer recurrence in young adults.
Subject(s)
Exome Sequencing , Neoplasm Recurrence, Local , Tongue Neoplasms , Tumor Suppressor Protein p53 , Humans , Tongue Neoplasms/genetics , Tongue Neoplasms/pathology , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Tumor Suppressor Protein p53/genetics , Young Adult , Male , Adult , Female , Frameshift Mutation/geneticsABSTRACT
Oral squamous cell carcinoma (OSCC) is one of the most important medical and socio-economic problems in many of the developed countries worldwide, due to the high mortality. The incidence of OSCC among individuals under 45 years of age is growing every year; however, the aetiological factors and pathogenetic mechanisms are poorly understood. This review summarizes the available information regarding clinicopathological features, extrinsic and intrinsic aetiological factors, and the molecular and immune landscape of early-onset OSCC. This cancer shows high recurrence rates and is not associated with the aetiological factors specific to adult-onset OSCC. Young adults with OSCC are not infected with human papillomavirus and rarely consume alcohol or tobacco, but more frequently use smokeless tobacco. Data from single studies indicate the hereditary nature of early-onset OSCC: the KIR2DL1+-HLA-C2+ genotype and MMP-1 2 G allele are frequently detected in young patients. Early-onset OSCC shows specific genetic, epigenetic, transcriptomic, and proteomic changes. The tumour microenvironment in early-onset OSCC is tolerogenic rather than immunogenic. All of the data suggest that OSCC in young patients is a separate clinical entity with a specific aetiology and pathogenesis. Further studies are needed to reveal the causes and molecular targets of early-onset OSCC for the development of preventive and therapeutic strategies.