Rna later tissue stabilization solution

The tissue samples were collected from 8 female breast cancer patients registered in Umraniye Training and Research Hospital (UEAH) between 2016 and 2018. Informed consent was obtained from all subjects involved in the study, which was conducted according to the guidelines of the Declaration of Helsinki, and approved by the Ethics Committee of University of Health Sciences Istanbul Umraniye Teaching and Research Hospital (UEAH), protocol code BD8082998622/4864. After surgery (mastectomy and lumpectomy) of the patients, fresh primary tumor and neighboring normal breast tissues were taken from the dissection material. Tissue samples were stored into RNA Later Tissue Stabilization Solution (Ambion) at -20°C. Frozen tissue samples were homogenized by grinding with liquid nitrogen and lysed in Tissue Protein Extraction Reagent, T-PER^™(Thermo Scientific, USA) augmented with 1x PhosSTOP (Roche) and 1x cOmplete Protease Inhibitor Cocktail (Roche). Then, the homogenates were centrifuged at 10000 g at 4°C for 5 min, and the supernatants were collected. Total protein concentration was measured by Bradford assay.

Breast tissue samples were obtained from 30 female breast cancer patients, with a mean age of 52 years, who were recruited in Umraniye Training and Research Hospital (UEAH) in Istanbul between 2015 and 2017. All patients gave their informed consent for usage of their specimen for research. The study was approved by the ethical committee at the Department of General Surgery of UEAH. Patients did not receive any chemotherapeutic treatment before surgery. Fresh primary tumor tissues and normal breast tissues from the same patients were taken from dissection material after surgery (mastectomy and lumpectomy). Molecular subtypes of tumor samples were graded by an experienced pathologist. Normal breast tissue was taken 1 cm away from the tumor. Approximately 0.5 cm³ of tissue samples were spared for storage. A fraction of the tissue was immediately transferred into 1 ml RNA Later Tissue Stabilization Solution (Ambion) for short term storage at − 20 °C, while the rest was formalin-fixed for 24 h and paraffin-embedded (FFPE) for long term storage.