Decreased B16F10 melanoma growth and impaired tumour vascularization in BDF1 mice with quercetin-cyclodextrin binary system.

The aim of this work was to study the inclusion behaviour of a poorly water-soluble bioflavonoid, quercetin, towards sulfobutyl ether-7beta-cyclodextrin. It also involves angiogenesis inhibition in-vivo in addition to in-vitro human cancer cell growth inhibition study of quercetin and its cyclodextrin complex. Drug-cyclodextrin solid inclusion complexes were prepared and characterized in solution and in the solid state. An in-vitro anti-proliferation study using plain drug and its solubilized form was carried out on human cancer cell lines of different origin. Further, an in-vivo tumour growth inhibition study was carried out using a mouse melanoma model. Histological sections of tumours were examined for the evaluation of tumour microvessel density. Significant enhancement of the solubility and dissolution rate of the quercetin, which occurred after complexation, might be attributed to the decrease in crystallinity of drug. SBE7betaCD complex of quercetin was more potent for inhibiting cell proliferation in human erythroleukaemia and cervix cancer cells. Decreased tumour microvessel density in mouse melanoma after oral quercetin administration led to diminished tumour cell proliferation. Quercetin-SBE7betaCD complex showed significantly improved anti-cancer activity at much lower concentration than the plain drug, providing evidence for dose reduction without affecting therapeutic efficacy when using cyclodextrin carriers.