Related Experiment Video
Updated: Jun 5, 2025
Retrospective MicroRNA Sequencing: Complementary DNA Library Preparation Protocol Using Formalin-fixed Paraffin-embedded RNA Specimens
Published on: May 5, 2018
MiRNA in archival serum samples derived from breast cancer patients treated with neoadjuvant chemotherapy vs freshly
Marcin Kubeczko1, Patrycja Tudrej1, Tomasz Tyszkiewicz1
1Maria Sklodowska-Curie National Research Institute of Oncology, Gliwice Branch, Poland.
Background:
Liquid biopsy, including miRNA profiling, is a promising approach to identify breast cancer (BC) resistance. However, the effect of long-term storage on the quality of miRNA assessment in archival serum has not been fully addressed.
Objectives:
We aimed to determine whether miRNAs were recoverable from long-stored serum samples to subsequently evaluate prognostic and predictive miRNA value in the archival collection of samples from patients treated with neoadjuvant chemotherapy at Maria Sklodowska-Curie National Research Institute of Oncology, Gliwice, Poland.
Material And Methods:
We have evaluated miRNA quantity in serum samples stored for up to 12 years. Additionally, we compared miRNA expression in archival samples to freshly collected samples derived from advanced BC patients.
Results:
Forty BC patients were included in the study. Archival samples were derived from 20 BC patients treated with radical intent between 2011 and 2015. Freshly collected samples were collected from 20 advanced BC patients in 2022. miRNA was present in archived serum samples frozen at -80C° for at least 12 years. Additionally, we found significantly different expressions between the 2 analyzed groups. Expression of circulating miR-16, -17, -18a, -20a, -21, -27a, -30b, -222, and -326 were significantly higher in archival samples, whereas expression of circulating miR-19a, -29b, -29c, -128, -145, -146a, -193b, -195, -200b, -210, -221, -424, and -451a were lower than in freshly collected samples. In 14 miRs, we observed expression in both groups; however, differences were statistically insignificant (miR-1, -7a, -10b, -19b, -34a, -99a, -106b, -122, -125b, -155, -200a, -205, -223, -340).
Conclusions:
MiRNA can be identified from long-stored samples, making large prospectively collected serum repositories with long follow-up time an invaluable source for miRNA biomarker discovery.
