RNA degradation in human breast tissue after surgical removal: a time-course study

There is much interest in the study of human malignancy using gene expression profiling techniques. Expression profiles obtained from microarrays utilize RNA extracted from the tissue in question. Currently, cell cultures or fresh tissue processed "quickly" are used in these studies. To our knowledge, there are no published reports of a time-course of RNA degradation in surgically removed breast tissue. Such a time-course study is critically needed. We obtained normal breast tissue from breast reduction surgery. Portions of breast tissue kept at room temperature were sampled and placed into RNAlater to preserve RNA at different time-points from 10 min to 3 h after the surgical removal. We evaluated total RNA integrity from each specimen using agarose gel electrophoresis and real-time quantitative RT-PCR analysis of four genes. Electrophoresis showed good-quality, intact RNA at all time points up to 3 h. Quantitative RT-PCR showed no difference in amplified products among all samples. Our study showed that there was no loss of RNA integrity in normal breast tissue for up to 3 h after surgical removal.