Asakawa Takeshi, Esumi Mariko, Endo Sohei, Kida Akinori, Ikeda Minoru
Department of Otolaryngology-Head and Neck Surgery, Nihon University School of Medicine, Japan.
Cancer. 2008 Feb 1;112(3):527-34. doi: 10.1002/cncr.23200.
Although genetic abnormalities on 3p have been suggested to be linked to the development of squamous cell carcinoma of the head and neck, to the authors' knowledge no study to date has examined such genetic abnormalities in patients with squamous cell carcinoma of the tongue. In the current study, loss of heterozygosity (LOH) was evaluated at several loci within 3p, including the von Hippel-Lindau gene (VHL), in samples of tongue squamous cell carcinoma. In addition, the coding region of the intact VHL allele was screened for sequence mutations.
DNA was extracted from tumor and nontumor tissues collected from 28 patients with tongue squamous cell carcinoma. LOH was investigated by analysis of single nucleotide polymorphisms within exon 3 of VHL and by microsatellite analysis within another 10 loci. Mutation analysis of the VHL gene was performed by polymerase chain reaction (PCR) amplification and sequencing of the coding region of the gene.
LOH within VHL was found at a high frequency (45.5%) within the tumor. However, mutations of the VHL gene were not detected in all tumor samples. LOH of other microsatellite markers on 3p was observed in 27.3% to 50% of tumor samples. Eleven (58%) of 19 samples that were informative at more than 2 loci exhibited LOH of at least 1 locus; 10 of these 11 cases exhibited LOH at multiple loci.
A wide range of deletions in 3p, including at the VHL gene, may play a role in the development of tongue cancer.
尽管已有研究表明3p上的基因异常与头颈部鳞状细胞癌的发生有关,但据作者所知,迄今为止尚无研究对头颈部鳞状细胞癌患者的此类基因异常进行检测。在本研究中,对舌鳞状细胞癌样本中3p区域内的几个位点,包括冯·希佩尔-林道基因(VHL),进行杂合性缺失(LOH)评估。此外,还对完整VHL等位基因的编码区进行序列突变筛查。
从28例舌鳞状细胞癌患者的肿瘤组织和非肿瘤组织中提取DNA。通过分析VHL基因外显子3内的单核苷酸多态性以及另外10个位点的微卫星分析来研究LOH。通过聚合酶链反应(PCR)扩增和对该基因编码区进行测序来进行VHL基因的突变分析。
在肿瘤中发现VHL基因内的LOH频率较高(45.5%)。然而,并非在所有肿瘤样本中都检测到VHL基因突变。在27.3%至50%的肿瘤样本中观察到3p上其他微卫星标记的LOH。在19个在2个以上位点具有信息性的样本中,有11个(58%)显示至少1个位点的LOH;这11例中的10例在多个位点显示LOH。
3p上广泛的缺失,包括VHL基因,可能在舌癌的发生中起作用。