Cinchonine, a potent efflux inhibitor to circumvent anthracycline resistance in vivo.

Circumvention of multidrug resistance is a new field of investigation in cancer chemotherapy, and safe and potent multidrug resistance inhibitors are needed for clinical use. We investigated several analogues of quinine for their ability to increase anthracycline uptake in resistant cancer cells. Cinchonine was the most potent inhibitor of anthracycline resistance in vitro, and its activity was little altered by serum proteins.

Monitoring and treatment of minimal residual cancer of the prostate.

In manifest prostatic carcinoma, partial and complete remissions are obtained in 14-44% of patients as judged by different sets of criteria, but in up to 61% as judged by a decrease in prostatic acid phosphatase. Moreover, this decrease is poorly correlated to that of prostatic size. Prostatic acid phosphatase is therefore considered to be a relatively non-specific tumor marker.

Phase II trial with D-Trp-6-LH-RH in prostatic carcinoma: comparison with other hormonal agents.

Various approaches to hormonal treatment of prostate carcinoma are discussed. Eighty-one patients with prostatic carcinoma, eight with stage B, nine with stage C, and 64 with stage D disease, were treated subcutaneously daily for 3 months with the LH-RH agonist D-Trp-6-LH-RH (Decapeptyl) in order to evaluate the incidence of remissions according to WHO recommendations for oncologic trials. The findings were compared to those obtained with other hormonal therapies of prostatic carcinoma according to the statistical method of "expected response rate" as adapted by Lee and Wesley for phase II trials.