Dichloroacetophenone biphenylsulfone ethers as anticancer pyruvate dehydrogenase kinase inhibitors in non-small cell lung cancer models.

Pyruvate dehydrogenase kinase 1 (PDK1) is an important metabolic enzyme which is often overexpressed in many types of cancers, including non-small-cell lung cancers (NSCLC). Targeting PDK1 appears to be an attractive anticancer strategy. Based on a previously reported moderate potent anticancer PDK1 inhibitor, 64, we developed three dichloroacetophenone biphenylsulfone ethers, 30, 31 and 32, which showed strong PDK1 inhibitions of 74%, 83% and 72% at 10 µM, respectively. Then we investigated the anticancer effects of 31 in two NSCLC cell lines, namely, NCI-H1299 and NCI-H1975. It was found that 31 exhibited sub-micromolar cancer cell IC50s, suppressed colony formation, induced mitochondrial membrane potential depolarization, triggered apoptosis, altered cellular glucose metabolism, with concomitant reductions in extracellular lactate levels and enhanced the generation of reactive oxygen species in NSCLC cells. Moreover, 31 significantly suppressed the tumor growth in an NCI-H1975 mouse xenograft model, outperforming the anticancer effects of 64. Taken together our results suggested that inhibition of PDK1 via dichloroacetophenone biphenylsulfone ethers may provide a novel direction leading to an alternative treatment option in NSCLC therapy.

Recent developments of human monocarboxylate transporter (hMCT) inhibitors as anticancer agents.

Cancer cells metabolize glucose via anaerobic glycolysis, with lactate formed in the cytosol as the end-product. To avoid intercellular acidification, excessive lactate and proton are excreted by monocarboxylate transporters (MCTs), which are often overexpressed in different malignant cancers. Targeting the MCT-mediated lactate/proton efflux makes MCTs a potentially interesting anticancer target. Although X-ray co-crystal structures of human MCTs with inhibitors are not yet available, homology models have been established, which helped to rationalize the binding modes and the design of new MCT inhibitors. In this review, we discuss the structures and functions of MCTs as well as recently reported small-molecule MCTs inhibitors. We assess the current development of MCT inhibitors and highlight possible directions for future development.

Novel pyrrolobenzoxaboroles: design, synthesis, and biological evaluation against Trypanosoma brucei.

Human African trypanosomiasis is a fatal parasitic infection caused by the protozoan Trypanosoma brucei. The development of novel antitrypanosomal agents is urgently needed. Here we report the synthesis and structure-activity relationship of a new class of benzoxaboroles as antitrypanosomal agents. These compounds showed antiparasitic IC50 values ranging from 4.02 to 0.03 µg/mL and satisfactory cytotoxicity profile. Three of the lead compounds were demonstrated to cure the parasitic infection in a murine acute infection model. The structure-activity relationship of the pyrrolobenzoxaboroles are also discussed.