p16基因结构及表达异常与周围型肺癌CT征象的关系

目的：探讨p16基因结构及表达异常与周围型肺癌CT征象的相关性。方法：利用免疫组织化学、聚合酶链反应-单链构象多态性分析（PCR-SSCP）方法检测52例周围型肺癌患者癌肺组织和癌旁肺组织中p16基因的表达水平及第2外显子突变，并与其CT征象进行相关性研究。结果：52例肺癌患者癌组织中p16基因蛋白丢失率为53.8％（28／52），第2外显子缺失/突变率为23.1％（12/52）；p16基因的缺失和蛋白的丢失率在不同临床分期的各组间的差异有统计学意义（P<0.05），但在不同病理类型、分化程度的各组间差异无统计学意义（P>0.05)。有细毛刺、棘突、胸膜凹陷及淋巴结转移等CT征象的肺癌患者，p16基因的缺失和蛋白的丢失率明显高于无以上征象者（P<0.05）；而在不同肿瘤大小、有无分叶、有无空洞、不同增强值方面，各组的p16基因的缺失和蛋白的丢失率差异无统计学意义（P>0.05)。结论：p16基因突变及表达异常可能在肺癌的发生、发展中起重要作用，并与肺癌患者CT征象有关。 p16基因可作为临床诊断及预后评估的检测指标。

CT appearance and p16 gene abnormality of peripheral lung cancer

Objective To investigate the relationship between the mutation and abnormal expression of p16 gene in peripheral lung carcinoma and its CT manifestations. Methods Immunohistochemistry and PCR-SSCP were used to detect P16 protein expression and p16 gene mutation of 52 cases of peripheral lung cancer. All patients were scanned with spiral CT before the operation and proved by pathology. Results Of the 52 cases of lung cancer tissues, the negative expression rate of p16 gene protein was 53.8% (28/52), and the deletion or mutation rate of the exon 2 was 23.1%(12/52). There were significant statistical differences of p16 gene defect and its protein loss rates among groups of different clinical stages ( P <0.05), but among groups of different tissue types, different differentiation degree p16 gene defect and its protein loss rates showed no significant statistical difference ( P >0.05). In lung cancer patients with CT appearances of thin spicule, speculated protuberance, pleural indentation, and metastasis of lymph node, p16 gene and its protein loss rates were much higher than those without CT manifestations mentioned above ( P < 0.05). However, there were no statistical differences among groups of different tumor sizes, with or without lobulation, with or without cavity, and different contrast enhanced CT values ( P >0.05). Conclusion p16 gene mutation and abnormal expression may play an important role in the occurrence and development of lung cancer,and it is relative to CT appearances of lung cancer. p16 gene may be used as a predicting index for clinical diagnosis and prognosis assessment.