Repeated-dose toxicity of HSP27-binding heptapeptide in mice

Heptapeptide, including seven amino acids of the PKCδ V5 region, which can bind HSP27 and abrogate HSP27-mediated resistance against IR and cisplatin (), was examined for single- and repeated-dose toxicity in mice. The single-dose experiment was performed with an intravenous and intraperitoneal injection of 100 mg/kg of heptapeptide, and the repeated-dose experiment was 14 doses over 28 days at 0, 5, 25, and 100 mg/kg of heptapeptide. Observations included clinical signs, mortality, body and organ weights, hematology, and serum biochemistry. No effects of heptapeptide on detected parameters were observed, and these findings indicated heptapeptide may be a possible therapeutic candidate without significant toxicity.