DNA as a target for anticancer compounds screening directly by resonance light scattering technique

Anticancer drugs which selectively interact with DNA can change DNA's conformation and inhibit the duplication or transcription of DNA. An instrument-based assay for directly screening DNA-targeted anticancer drugs using resonance light scattering (RLS) technique with a common spectrofluorometer was proposed. To monitor the proposed screening method, the interactions between three anticarcinogens (Adriamycin (ADM), Bleomycin A (BLMA), Actinomycin D (ACTD)) and DNA were studied. The sequence of binding constants for the three anticarcinogens obtained from RLS spectra is: K-RLS (ACTD, 9.43 x 10(5) L mol(-1)) > K-RLS (ADM, 6.67 x 10(5) L mol(-1)) > K-RLS (BLMA, 8.88 x 10(3) L mol(-1)) and of binding numbers is: N-RLS (ACTD, 3.36 mmol g(-1)) < N-RLS (ADM, 3.81 mmol g(-1)) < N-RLS (BLMA, 57.44 mmol g(-1)). From the results we got the sequence of combination intensity between these three drugs and DNA as follows: ACTD-DNA > ADM-DNA > BLMA-DNA, which was completely consistent with drug activity. The conclusion indicated that the present method was direct, rapid, reliable and was another important innovation of the application of RLS technique.