BTK and mantle cell lymphoma: To establish the anti-cancer activity of SRX3305, we performed cytotoxicity experiments treating the MCL cell lines JeKo-1, Mino, Granta, JeKo-1 BTK C481S and Mino BTK C481S with increasing concentrations of SRX3305, SRX3306 or the BTK inhibitor Ibrutinib.