Cathepsin B cleavable novel prodrug Ac-Phe-Lys-PABC-ADM enhances efficacy at reduced toxicity in treating gastric cancer peritoneal carcinomatosis: an experimental study

Cancer. 2012 Jun 1;118(11):2986-96. doi: 10.1002/cncr.26596. Epub 2011 Oct 17.

Abstract

Background: Doxorubicin (Adriamycin) is effective in gastric cancer treatment, but with severe dose-dependent toxicities. A novel prodrug of doxorubicin (Ac-Phe-Lys-PABC-ADM) is designed to deliver free doxorubicin relying on cathepsin B and reduce side effects. The authors examined the antitumor effect and toxicities of Ac-Phe-Lys-PABC-ADM against gastric cancer peritoneal carcinomatosis.

Methods: SGC-7901 gastric cancer cell line was used for the study. The in vitro study investigated the effects of doxorubicin and Ac-Phe-Lys-PABC-ADM on cell growth dynamics and cell cycle. The in vivo study investigated the efficacy and toxicity of Ac-Phe-Lys-PABC-ADM on a nude mice model of peritoneal carcinomatosis, with doxorubicin as positive control.

Results: In the in vitro study, Ac-Phe-Lys-PABC-ADM had a lower dose-dependent inhibitory effect on SGC-7901 cells. In the in vivo study of control, doxorubicin, and Ac-Phe-Lys-PABC-ADM groups, the median experimental peritoneal carcinomatosis indexes were 6, 1.5, and 1, respectively (P = .004); the body weights were 24.32 ± 1.40 g, 18.40 ± 2.97 g, and 23.61 ± 0.80 g, respectively (P = .000). Biochemical studies showed that Ac-Phe-Lys-PABC-ADM had significantly lower toxicities on the bone marrow, liver, kidney, and particularly heart. Histopathological studies of the control, doxorubicin, and Ac-Phe-Lys-PABC-ADM groups found significant myocardium toxicities in 3, 7, and 4 animals, respectively.

Conclusions: Ac-Phe-Lys-PABC-ADM could be an effective molecular targeting drug to treat gastric cancer peritoneal carcinomatosis with enhanced efficacy and reduced toxicity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carcinoma / drug therapy*
  • Carcinoma / secondary*
  • Cathepsin B / metabolism*
  • Cell Cycle / drug effects
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Doxorubicin / adverse effects
  • Doxorubicin / analogs & derivatives*
  • Doxorubicin / therapeutic use*
  • Heart / drug effects
  • Humans
  • Male
  • Mice
  • Mice, Nude
  • Molecular Targeted Therapy
  • Oligopeptides / therapeutic use*
  • Peritoneal Neoplasms / drug therapy*
  • Peritoneal Neoplasms / secondary*
  • Prodrugs / adverse effects
  • Prodrugs / therapeutic use*
  • Stomach Neoplasms / pathology*
  • Xenograft Model Antitumor Assays

Substances

  • Oligopeptides
  • Prodrugs
  • acetyl-phenylalanyl-lysyl-para-aminobenzyloxycarbonyl-adriamycin
  • Doxorubicin
  • Cathepsin B