BIRC5 and cancer: To determine the mechanism associated with variable MPM cell drug response, as established from our in vitro and in vivo results for MSTO-211H and H226, we investigated the expression levels of a number of genes known to mediate anti-apoptosis (i.e., IAP gene family) and survivin-related drug uptake/transporter genes that are known to mediate drug resistance in other cancer types [74,75,76].