DETECTION OF CELLCYCLE REGURATRY GENES,ONCOGENES,TUMOR SUPPRESSORGENES IN HUMAN ORAL SQUAMOUS CELL CARCINOMA.

一个新的抑癌基因--细胞周期蛋白依赖性激酶4抑制基因已被克隆并定位在9p染色体上，该基因可能存在口腔鳞癌的抑癌基因。为了阐明该基因异常是否与口腔鳞状细胞癌的发生有关，本研究采用聚合酶链式反应-单链构象多态性分析、DNA直接测序和缺失分析等方法对口腔鳞癌原发灶和鳞癌细胞系的基因组DNA进行了检测。57%的细胞系含有无义突变或错义突变。在本研究检测到的4个无义突变中，有3个发生在80密码子(CGA*TGA；Arg*Stop)，提示80密码子是p16基因的突变热点。这些结果表明p16基因在口腔鳞状细胞癌的一个亚型的进展中起作用。

A new tumor-suppressor gene, the cyclin dependent kinase 4 inhibitor gene, has been cloned and mapped on chromosome 9p where putative tumor suppressor gene of the oral squamous cell carcinoma (SCC) may be present. In order to elucidate whether abnormalities of this gene could contribute tot the tumor genesis of oral SCC,genomic DNAs from primary lesions and SCC cell lines were examined by PCR-SSCP analysis, direct DNA sequencing, and deletion analysis. Fifty seven percents cell lines contained non-sense mutations or mis-sense mutations. Particularly, 3 of 4 non-sense mutations detected in the present study were found in codon 80 (CGA*TGA ; Arg*Stop), suggesting that codon 80 was a mutational hot spot of the p16 gene. These results suggest that the p16 gene plays a role in the progression of a subtype of human oral SCC.