PGP and ovarian cancer: In addition to having inhibited P-gp activity in these two types of cancers [35], a study by Morsy et al. (2018) [36] found, through in silico and in vitro studies, that piperine was able to inhibit P-gp in ovarian cancer cells, suggesting that this phytochemical would be a promising adjuvant in the treatment with doxorubicin.