PTEN在4种胰腺癌细胞系中的表达及意义

目的 通过检测PTENmRNA和蛋白在4种胰腺癌细胞系中的表达，筛选出PTEN不表达或低表达的胰腺癌细胞系，为进一步研究提供依据。方法用DMEM培养液对胰腺癌ASPC-1，MiapacaⅡ，JF305，MiapacaⅠ细胞进行单层传代培养，取指数生长期细胞，采用RT-PCR法和细胞免疫组化法检测PTENmRNA和蛋白在上述4种胰腺癌细胞系中的表达。结果RT-PCR结果显示，位于209bp，381bp处的条带分别为PTEN，13-actinmRNA的扩增片段，ASPC-1，MiapacaⅡ，JF305，MiapacaⅠ细胞PTEN mRNA表达分别为18．76％，32．63％，77．45％，123．07％，ASPC-1细胞系PTENmRNA表达最低。免疫组织化学法检测PTEN蛋白表达水平显示，在ASPC-1细胞中PTEN蛋白有少量表达，而在JF305和MiapacaⅠ细胞系中PTEN蛋白表达较高，胞浆中可见大量棕黄色颗粒。结论ASPC-1细胞系中PTENmRNA和蛋白均呈低表达，因此，该细胞系可作为良好的研究工具，为进一步将PTEN转染该细胞系，以研究PTEN对胰腺癌的抑癌作用提供依据。

EXPRESSION OF PTEN IN FOUR PANCREATIC CANCER CELL LINES AND ITS SIGNIFICANCE

Objective To select a pancreatic cancer cell line with low PTEN mRNA and protein ex pression from 4 different pancreatic cancer celt lines （Miapaca Ⅰ , Miapaca Ⅱ JF305 and ASPC-1） for further research. Methods The Miapaca Ⅰ , Miapaca Ⅱ, JF305 and ASPC-1 cells were cultured in the DMEM culture medium. We measured PTEN mRNA expressions of Miapaca Ⅰ , Miapaca Ⅱ, JF305 and ASPC-1 with RT-PCR assay. The PTEN protein expressions were measured with cellular immunohistochemical staining. Results The results showed that zones located at 209bp were the amplification fragment of PTEN mRNA and zones located at 381bp were 13-actin mRNA. PTEN mRNA positive rates were respectively 18. 76%, 32.63M, 77.45% and 123.07% in ASPC-1, Miapaca Ⅱ, JF305 and Miapaca Ⅰ lines. The lowest PTEN mRNA expression was found in ASPC-1 cells. In the immunohistochemical staining results, the expression of PTEN protein was less in ASPC-1 cells, but much more in Miapaca Ⅱ, JF305 and Miapaca Ⅰ cells with a lot of brown particles inside the cytoplasm. Conclusion Our findings suggest that PTEN mRNA and PTEN protein exhibit the lowest expression in the ASPC-1 celt line among the 4 pancreatic cancer cell lines. These results may provide a basis for further research on exogenous PTEN transfection of the pancreatic cancer cell lines.