EXPRESSION AND SIGNIFICANCE OF PTEN IN ENDOMETRIAL CARCINOMA

Objective: To investigate the expression of PTEN in endometrial carcinoma and its clinical significance. Methods: Reverse transcriptase-polymerase chain reaction and Western-blot methods were used to detect PTEN expression in 28 cases of endometrial carcinoma. Results: mRNA and protein expression levels of PTEN in endometrial carcinomas were significantly lower than those in normal endometrium (P<0.01). Conclusion: PTEN may play an important role in the tumorigenesis of endometrial carcinoma.

食管鳞癌FHIT基因等位缺失及其表达下调

背景与目的:食管癌3号染色体短臂(3p14)经常发生缺失或易位,脆性组氨酸三联体基因(fragilehistidinetriad,FHIT)定位于3p14.2,在许多肿瘤中均发现此基因缺失或表达异常。然而,FHIT基因在食管癌中变化的形式以及FHIT改变在食管癌发生、发展中的作用尚未明确。本研究旨在探讨FHIT基因在食管鳞癌中的变化情况及其意义。方法:用微卫星分析方法观察80例食管鳞癌中FHIT基因的缺失,并用半定量逆转录聚合酶链反应法(reversetranscriptase-polymerasechainreaction,RT-PCR)分析其中20例食管鳞癌FHITmRNA表达的变化。结果:FHIT基因内标志D3S3356、D3S3378、D3S3361在本系列的标本中为纯合子。FHIT基因旁侧微卫星位点D3S1234和D3S1540在癌旁组织具有较高的杂合度,信息个体中肿瘤组织的杂合性丢失(lossofheterozygosity,LOH)频率分别为57.69%(30/52)和67.86%(38/56)。在20例同时获得其RNA的标本中,15(75%)例出现FHIT基因的mRNA表达下调,且多发生于DNA水平伴有LOH的病例。但LOH发生与mRNA表达下调并不完全一致。结论:食管癌中FHIT基因频发异常,LOH是FHIT基因表达失调的主要机制,表观遗传学(epigenetic)变化可能与部分食管癌中FHIT基因的表达下调相关。