Anti-tumor activity of C36L1 peptide due to microtubule depolymerization

Recently, C.R. Figueiredo et al. examined the mechanism of action underlying the anti-tumor effects of the complementarity-determining region (CDR) C36L1 synthetic peptide derived from the V_L CDR1 of the C36 Fab fragment of the anti-vaccinia immunoglobulin.  This CDR exhibits both anti-tumor activity and functions as a microtubule destabilizing molecule.  Here, the authors investigated whether its microtubule-destabilizing effect is responsible for its anti-tumor activity. The authors found that the peptide induces apoptotic effects on multiple cancer cells both in vitro and in vivo, inhibits tumor cell migration and invasion, and arrests cell cycle primarily in the G2M phase. These effects follow internalization of the C36L1 peptide which then selectively binds to microtubules and destabilizes the tubulin filaments. Microtubule polymerization and depolymerization dynamics were examined in living cells and under cell-free conditions. Cytoskeleton’s fluorescent tubulin polymerization assay kit (Cat. # BK011P) was an essential reagent in this study, complementing the in vivo results and in vitro cell culture data which demonstrated conclusively that the C36L1 peptide targets microtubules in exerting its anti-tumor effects. These findings contribute to the growing and intense field of research focused on developing peptide-based cancer vaccines.

 C.R. Figueiredo et al. 2015. A novel microtubule de-stabilizing complementarity-determining region C36L1 peptide displays anti-tumor activity against melanoma in vitro and in vivo. Sci. Rep. 5, 14310.