Generation and characterization of chemoresistant embryonal rhabdomyosarcoma RD line

Rhabdomyosarcoma (RMS) represents one of the most common soft tissue sarcoma arising in humans, typically during childhood. It develops at mesenchymal level, since myogenic precursors fail to differentiate. RMS can be classified into two major histotypes: embryonal (ERMS) and alveolar (ARMS). In particular, we want to develop a chemoresistant embryonal RD cell line. Cells are treated using an anticancer drug as selective agent. Chosen drug is doxorubicin, known to be widely utilized against different types of cancer. It shows cytotoxic effect in vivo, with a wide range of action. Doxorubicin primarily works as a Topoisomerase II inhibitor, intercalating in DNA helix, but it is also known to be involved in ROS generation. From previous work in the field, it has been observed that RD cells present a doxorubicin IC50 of 1 µM. Based on this calculation, two strategies have been considered: Continuous and Dose-escalation. While Continuous selection presents a fixed dose of administration, Dose-escalation is expected to double the dose from time to time. Once this model will be established, our goal will focus on further investigation of biochemical profile, to understand which metabolites are connected with doxorubicin resistance in vitro.