CLDN2 and prostate cancer: 4. By suppressing the synthesis of claudin-2, suppressing the NF-κB pathway, reducing cytoplasmic reserves of GSH (reduced glutathione), and decreasing apoptotic regulators (cIAP1, cIAP-2, and XIAP), caffeinic acid phenyl ester (CAPE) is effective in fighting MDR in lung and prostate cancer.