Heah Khor Goot, Hassan Mohamed Ibrahim Abu, Huat Siar Chong
Department of Oral Biology, Faculty of Dentistry, Universiti Technologi MARA, Shah Alam, Malaysia.
Asian Pac J Cancer Prev. 2011;12(4):1017-22.
Oral squamous cell carcinoma (OSCC) has high local recurrence, partly caused by the lack of clear margin identification on surgical removal of cancerous tissues. Direct visualization by immunostaining and fluorescent in situ hybridization (FISH) in tissue sections gives more definite information about genetic damage at margins with appropriately selected biomarkers.
To determine the usefulness of immunohistochemical techniques and FISH of the tumour suppressor TP 53 gene to identify microinvasion in marginal tissue sections and to relate the possible correlation between protein expression and genetic aberrations in OSCC cases in Malaysia.
Immunohistochemistry and FISH of TP 53 genes were applied on 26 OSCC formalin fixed paraffin embed (FFEP) blocks selected from two oral cancer referral centers in Malaysia.
For p53 protein immunohistochemistry, 96% of the 26 OSCC studied showed positive immunostaining at the excision margins. In FISH assay, 48.9±9.7% of the cancerous cells were monoploid for p53 probe signals, 41.0±9.5 % were diploid, and 10.2±7.8 % were polyploid. A correlation between p53 immunostaining and TP53 gene aberrations was noted (p< 0.05).
Immunohistochemical analysis of p53 protein expression and FISH of TP53 gene could be applied as screening tool for microinvasion of OSCC.
口腔鳞状细胞癌（OSCC）局部复发率高，部分原因是手术切除癌组织时难以明确切缘。通过免疫染色和荧光原位杂交（FISH）对组织切片进行直接可视化，利用适当选择的生物标志物可提供有关切缘遗传损伤的更确切信息。
确定免疫组织化学技术和肿瘤抑制基因TP 53的FISH检测在识别边缘组织切片微浸润方面的实用性，并探讨马来西亚OSCC病例中蛋白表达与基因畸变之间的可能相关性。
对从马来西亚两个口腔癌转诊中心选取的26例OSCC福尔马林固定石蜡包埋（FFEP）组织块进行TP 53基因的免疫组织化学和FISH检测。
对于p53蛋白免疫组织化学检测，26例研究的OSCC中有96%在切除边缘显示阳性免疫染色。在FISH检测中，48.9±9.7%的癌细胞p53探针信号为单倍体，41.0±9.5%为二倍体，10.2±7.8%为多倍体。p53免疫染色与TP53基因畸变之间存在相关性（p<0.05）。
p53蛋白表达的免疫组织化学分析和TP53基因的FISH检测可作为OSCC微浸润的筛查工具。
