Study of Effectiveness of Different Patient-Derived Xenograft Cryopreservation Variants

Abstract

Patient-derived xenografts (PDXs) are an important experimental platform for studying the effectiveness of anticancer drugs. Maintaining a large number of tumor-bearing animals is impractical, and therefore both the development of new methods for PDX creation and their correct storage and reproduction are of decisive importance. PDX cryopreservation involves working with macroscopic objects which requires an approach different from the one used when working with individual cells. The search for the most reliable PDX cryopreservation methods preventing against the loss of valuable and irreplaceable tumor samples over time is important. The purpose of this study was to analyze the effectiveness of three different protocols for cryopreservation of PDX samples. 12 unique PDXs were cryopreserved according to three different protocols, and then the reanimated tumor specimens were implanted subcutaneously and assessed for graftability and the latency period. An analysis of results of various cryopreservation protocols showed that success of PDX cryopreservation depended on the freezing rate and the cryomix composition.