Nagai M A
Departamento de Radiologia, Faculdade de Medicina, Universidade de São Paulo, Brasil.
Braz J Med Biol Res. 1999 Jul;32(7):897-904. doi: 10.1590/s0100-879x1999000700015.
The genetic alterations observed in head and neck cancer are mainly due to oncogene activation (gain of function mutations) and tumor suppressor gene inactivation (loss of function mutations), leading to deregulation of cell proliferation and death. These genetic alterations include gene amplification and overexpression of oncogenes such as myc, erbB-2, EGFR and cyclinD1 and mutations, deletions and hypermethylation leading to p16 and TP53 tumor suppressor gene inactivation. In addition, loss of heterozygosity in several chromosomal regions is frequently observed, suggesting that other tumor suppressor genes not yet identified could be involved in the tumorigenic process of head and neck cancers. The exact temporal sequence of the genetic alterations during head and neck squamous cell carcinoma (HNSCC) development and progression has not yet been defined and their diagnostic or prognostic significance is controversial. Advances in the understanding of the molecular basis of head and neck cancer should help in the identification of new markers that could be used for the diagnosis, prognosis and treatment of the disease.
在头颈癌中观察到的基因改变主要是由于癌基因激活（功能获得性突变）和肿瘤抑制基因失活（功能丧失性突变），从而导致细胞增殖和死亡失调。这些基因改变包括癌基因如myc、erbB-2、EGFR和细胞周期蛋白D1的基因扩增和过表达，以及导致p16和TP53肿瘤抑制基因失活的突变、缺失和高甲基化。此外，经常观察到几个染色体区域的杂合性缺失，这表明其他尚未确定的肿瘤抑制基因可能参与了头颈癌的致瘤过程。头颈鳞状细胞癌（HNSCC）发生和发展过程中基因改变的确切时间顺序尚未明确，其诊断或预后意义也存在争议。对头颈癌分子基础认识的进展应有助于识别可用于该疾病诊断、预后和治疗的新标志物。
