In this work, we introduce a new customized anti-lung cancer peptide, CB1a, with IC50 of about 25.0 +/- 1.6 mu M on NCI-H460 lung cancer cells. Using a multi-cellular tumor spheroid (MCTS) model, results show that CB1a is potent in preventing the growth of lung cancer tumor-like growths in vitro. Additionally, atomic force microscopy (AFM) was used to examine cell surface damage of a single cancer. The mechanism for cell death under CB1a toxicity was verified as being largely due to cell surface damage. Moreover, with a treatment dosage of CB1a at 25 mu M, Young's module (E) shows that the elasticity and stiffness of cancer cell decreased with time such that the interaction time for a 50% reduction of E (IT50) was about 7.0 min. This new single-cell toxicity investigation using IT50 under AFM assay can be used to separately verify drug efficacy in support of the traditional IC50 measurement in bulk solution. These results could be of special interest to researchers engaged in new drug development. (C) 2012 Elsevier B.V. All rights reserved.
- Atomic force microscopy; CB1a, single cell; Cancer cell; Anticancer peptide