N a number of myeloma A Tagde et al3 Benefits BSO synergistically enhanced
N numerous myeloma A Tagde et al3 Results BSO synergistically enhanced L-PAM-induced cytotoxicity in nine MM cell lines, in presence of BMSC and MM cytokines, and in seven main MM cells We determined the cytotoxicity of clinically achievable levels of BSO (000 mM) and L-PAM (00 mM) in nine human MM cell lines working with the DIMSCAN cytotoxicity assay (Figure 1a). L-PAM as a single agent was very active against MM.1S, KMS-12-PE, MOLP-2 and NCI-H929, inducing X2 logs of cell kills at the maximum dose (50 mM). In the remaining 5 cell lines, L-PAM showed modest activity and induced p2 logs of cell kill. BSO alone had minimal to no activity in six cell lines and had modest activity in the OPM-2, KMS-12-PE and MM.1S lines. The combination of BSO L-PAM achieved synergistic cytotoxicity (combination index quantity (CIN)Figure 1. Representative dose response curves of BSO (black circles), L-PAM (white circles) and BSO L-PAM (black triangles) in nine MM cell lines. (a) Drug concentrations were 000 mM for BSO and 00 mM for L-PAM (Fixed ratio, BSO: L-PAM: 8:1). Cultures were treated with BSO for 24 h, at which time L-PAM was added, followed by 96 h of incubation before DIMSCAN cytotoxicity evaluation. Cell lines have been cultured in bone marrow level hypoxia (five O2). The survival fraction was determined by mean fluorescence with the treated cellsmean fluorescence of handle cells. Error bars represent s.d. (nX3). (b) Summary of cytogentic abnormality of MM cell lines (c) CINs have been calculated for fixed ratio of BSO and L-PAM (8:1) using CalcySyn application (Biosoft, Cambridge, UK). The CIN values o1 indicate synergism and 41 indicate antagonism effect.2014 Macmillan Publishers Restricted Blood Caspase 6 site Cancer JournalBSO L-PAM in a number of myeloma A Tagde et al4 p0.7) and induced 2 logs of cell kill in all nine MM cell lines like the eight lines established at progressive illness (PD) right after therapy (U266, OPM-2, NCI H929, KMS-12-PE, EJM, TX-MM-030h, MM.1S and MOLP-2),25 which involve lines with cytogenetic profiles associated with a poor prognosis (Figure 1b).25,38,39 The combination of BSO (200 mM) and L-PAM (25 mM) accomplished very robust synergism (CIN p0.1) in RPMI-8226 (TP53, KRAS and EGFR mutations) and U266 (TP53-mutation) cell lines,38,40 and robust synergism (CIN 0.1.3) was seen in MM.1S (TP53-wt and t(14;16)), KMS-12-PE (t(11;14) (q13;q32)) and EJM (TP53-mutation).25,38,40 BSO L-PAM was synergistic (CIN 0.three.7) in OPM-2 (t(4;14)(p16;q32)), NCI-H929 (t(4;14)) TX-MM-030h (post-BMT) and MOLP-2 (t(11;14)(q13;q32))39 cell lines (Figures 1a ).25,38 Identical results had been also obtained for all cell lines tested with BSO L-PAM when cultured in `standard’ culture situations (space air five CO2; Supplementary Figure 1). We assessed whether the activity of BSO L-PAM is attenuated by co-culture with MM cytokines (interleukin-6, insulin-like development factor-1 and vascular endothelial growth factor) and BMSCs. In all four cell lines tested, BSO L-PAM significantly (Po0.05) enhanced apoptotic cells (Annexin V and PI ) as compared with L-PAM (Figure 2a). Comparable towards the observation in MM cell lines, the combination therapy induced multi-logs of synergistic cell kill (CIN o1.0) (Figures 2b and c). Subsequent, we determined the efficacy of BSO L-PAM in freshly isolated main MM cells from clinical JAK2 Storage & Stability specimens. Consistent using the effects in MM cell lines, pretreatment with BSO synergistically (CIN o 1.0) enhanced L-PAM-induced cytotoxicity in all primary100 Annexin V Optimistic MM.1S 8.