In a rhodamine-based test for evaluating multidrug resistance to antitumor agents in LoVo/DOX cells, that overexpress both P-gp and CA XII, some of the coumarin derivatives 41 were able to revert the phenomenon, leading to an increased uptake of doxorubicin within the tumour cell, demonstrating thus the efficacy of the hybridisation approach.73 The gene discussed is PGP; the disease is neoplasm.