Beckhardt R N, Kiyokawa N, Xi L, Liu T J, Hung M C, el-Naggar A K, Zhang H Z, Clayman G L
Department of Head and Neck Surgery, University of Texas M.D. Anderson Cancer Center, Houston, USA.
Arch Otolaryngol Head Neck Surg. 1995 Nov;121(11):1265-70. doi: 10.1001/archotol.1995.01890110041008.
To characterize the HER-2/neu oncogene in head and neck squamous cell carcinoma (HNSCC) cell lines and tumor tissue specimens.
Molecular analysis of HER-2/neu oncogene amplification and expression in HNSCC cell lines by Southern, Northern, and Western blot techniques, and HER-2/neu oncoprotein expression in HNSCC tumor tissue sections by immunohistochemical analysis.
Eleven HNSCC cell lines, eight paired samples of frozen HNSCC tumor tissue specimens and adjacent nonmalignant mucosa, and 38 paraffin-embedded slides derived from HNSCC tumor specimens (including those from which the cell lines were derived) were analyzed.
Southern blot analysis showed twofold HER-2/neu gene amplification in two (18%) of the 11 HNSCC cell lines, MDA-1386 and Tu-167. Northern blot analysis showed messenger RNA overexpression in the same two cell lines, and to a lesser degree in MDA-1483. Western blot analysis showed high levels of HER-2/neu oncoprotein expression in two (18%) of the 11 cell lines (MDA-1386 and Tu-167), a moderate level of protein expression in one cell line (9%) (MDA-1483), and low levels of protein expression in eight cell lines (73%). Some HER-2/neu protein expression was seen in all of the HNSCC cell lines. Immunohistochemical analysis of the tumor tissue sections from which the cell lines were derived corroborated the Western blot results. Western blot analysis of frozen primary tumor specimens showed HER-2/neu oncoprotein overexpression in two (25%) of eight specimens. Immunohistochemical analysis showed high levels of protein expression in six (16%) of the 38 tumor tissue slides, moderate levels in 12 (31%), and low levels in 20 (53%).
The HER-2/neu oncogene is overexpressed in a subset of HNSCC tumors and cell lines. The results from Western blot and immunohistochemical analyses underscore a variable HER2/neu oncoprotein expression in HNSCC. Gene amplification was observed in a few of the cell lines, suggesting a potential mechanism of oncoprotein overexpression. Messenger RNA overexpression, however, can be seen in the absence of gene amplification, indicating that transcriptional or posttranscriptional control mechanisms must be involved. Further studies are indicated to determine the biologic role of HER-2/neu expression in the clinical progression of these lesions and to further define the molecular basis regulating its expression.
对人头颈部鳞状细胞癌（HNSCC）细胞系及肿瘤组织标本中的HER-2/neu癌基因进行特征分析。
采用Southern、Northern和Western印迹技术对HNSCC细胞系中的HER-2/neu癌基因扩增及表达进行分子分析，采用免疫组织化学分析对HNSCC肿瘤组织切片中的HER-2/neu癌蛋白表达进行分析。
分析了11个HNSCC细胞系、8对冷冻的HNSCC肿瘤组织标本及相邻的非恶性黏膜样本，以及38张来源于HNSCC肿瘤标本（包括那些细胞系所源自的标本）的石蜡包埋切片。
Southern印迹分析显示，11个HNSCC细胞系中的2个（18%），即MDA-1386和Tu-167，存在HER-2/neu基因两倍的扩增。Northern印迹分析显示，同样是这两个细胞系存在信使RNA过表达，MDA-1483的过表达程度较低。Western印迹分析显示，11个细胞系中的2个（18%）（MDA-1386和Tu-167）存在高水平的HER-2/neu癌蛋白表达，1个细胞系（9%）（MDA-1483）存在中等水平的蛋白表达，8个细胞系（73%）存在低水平的蛋白表达。在所有HNSCC细胞系中均可见到一些HER-2/neu蛋白表达。对细胞系所源自的肿瘤组织切片进行免疫组织化学分析，证实了Western印迹分析结果。对冷冻的原发性肿瘤标本进行Western印迹分析显示，8个标本中的2个（25%）存在HER-2/neu癌蛋白过表达。免疫组织化学分析显示，38张肿瘤组织切片中的6个（16%）存在高水平的蛋白表达，12个（31%）存在中等水平的蛋白表达，20个（53%）存在低水平的蛋白表达。
HER-2/neu癌基因在一部分HNSCC肿瘤及细胞系中过表达。Western印迹分析和免疫组织化学分析结果强调了HNSCC中HER2/neu癌蛋白表达的变异性。在少数细胞系中观察到基因扩增，提示这可能是癌蛋白过表达的一种潜在机制。然而，在无基因扩增的情况下也可见信使RNA过表达，这表明转录或转录后调控机制必定参与其中。需要进一步研究以确定HER-2/neu表达在这些病变临床进展中的生物学作用，并进一步明确调控其表达的分子基础。
