Design, synthesis and antitumor activity of a novel PEG-A6-conjugated irinotecan derivative.

A novel PEG-A6-conjugated irinotecan derivative 8 was designed and synthesized as antitumor agent by the PEGylation and A6-peptide modification of irinotecan. In vivo antitumor activity screening assay revealed that 8 exhibited better in vivo antiproliferation activity than irinotecan and its previous PEG-cRGD-conjugated derivative BGC0222 in MIA PaCa-2, NCI-H446, MDA-MB-231, HT-29 and NCI-N87 xenograft models, while the tumor of one in six mice in NCI-H446 assay and the tumors of two in six mice in MIA PaCa-2 assay completely subsided and disappeared within the 21-day period of 8-treatment, indicating that 8 should be a potential antitumor agent.

Design, synthesis and pharmacological evaluation of a novel PEG-cRGD-conjugated irinotecan derivative as potential antitumor agent.

A novel PEG-cRGD-conjugated irinotecan derivative BGC0222 was designed and synthesized as antitumor agent. Antitumor activity screening assay indicated that BGC0222 exhibited better in vitro antiproliferation activity than irinotecan and NKTR-102 against HT29, MIA PaCa-2 and MCF-7 tumor cell lines, with IC50 of 1.83 ±â€¯0.09 µM, 3.95 ±â€¯0.16 µM and 0.68 ±â€¯0.04 µM, respectively, while it displayed better in vivo antiproliferation activity than irinotecan and NKTR-102 in HT-29, MIA PaCa-2, NCI-H446, U-87 MG and MDA-MB-231 xenograft models. The action mechanism of BGC0222 was then investigated by integrin-binding competition (IBC) and chick chorioallantoic membrane (CAM) angiogenesis assays, which indicated that BGC0222 may exert antitumor activity by binding to αvß3 target and consequently inducing neovascularization effect. Pharmacokinetic analysis showed that BGC0222 could slowly and steadily release irinotecan, which was subsequently metabolized into 7-ethyl-10-hydroxycamptothecin (SN-38) in the whole blood.