Synthesis and screening of N-alkyl hydroxamates for inhibition of cancer cell proliferation

Cdc20: At the Crossroads between Chromosome Segregation and Mitotic Exit

Cell-division cycle protein 20 homologue (Cdc20) has important functions in chromosome segregation and mitotic exit. Cdc20 is the target of the spindle assembly checkpoint (SAC) and a key cofactor of the anaphase-promoting complex or cyclosome (APC/C) E3 ubiquitin ligase, thus regulating APC/C ubiquitin activity on specific substrates for their subsequent degradation by the proteasome. Here we discuss the roles of Cdc20 in SAC signalling and mitotic exit, describe how the integration of traditional approaches with emerging technologies has revealed new details of Cdc20 functions, comment about the potential of Cdc20 as a therapeutic target for the treatment of human malignancies, and discuss recent advances and controversies in the mechanistic understanding of the control of chromosome segregation during cell division.

Mining the Chemical Space: Application of 2/4-Nitrobenzenesulfonamides in Solid-Phase Synthesis

Polymer-supported benzenesulfonamides prepared from various immobilized primary amines and 2/4-nitrobenzenesulfonyl chloride have been used as key intermediates in different chemical transformations, including unusual rearrangements to yield a number of diverse privileged scaffolds. This review summarizes individual strategies in their application to date.

Expanding the Activity of Tissue Inhibitors of Metalloproteinase (TIMP)-1 against Surface-Anchored Metalloproteinases by the Replacement of Its C-Terminal Domain: Implications for Anti-Cancer Effects

Tissue inhibitors of metalloproteinases (TIMPs) are the endogenous inhibitors of the matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinases (ADAMs). TIMP molecules are made up of two domains: an N-terminal domain that associates with the catalytic cleft of the metalloproteinases (MP) and a smaller C-terminal domain whose role in MP association is still poorly understood. This work is aimed at investigating the role of the C-terminal domain in MP selectivity. In this study, we replaced the C-terminal domain of TIMP-1 with those of TIMP-2, -3 and -4 to create a series of "T1:TX" chimeras. The affinity of the chimeras against ADAM10, ADAM17, MMP14 and MMP19 was investigated. We can show that replacement of the C-terminal domain by those of other TIMPs dramatically increased the affinity of TIMP-1 for some MPs. Furthermore, the chimeras were able to suppress TNF-α and HB-EGF shedding in cell-based setting. Unlike TIMP-1, T1:TX chimeras had no growth-promoting activity. Instead, the chimeras were able to inhibit cell migration and development in several cancer cell lines. Our findings have broadened the prospect of TIMPs as cancer therapeutics. The approach could form the basis of a new strategy for future TIMP engineering.

Targeting Cdc20 as a novel cancer therapeutic strategy

The Anaphase Promoting Complex (APC, also called APC/C) regulates cell cycle progression by forming two closely related, but functionally distinct E3 ubiquitin ligase sub-complexes, APC(Cdc20) and APC(Cdh1), respectively. Emerging evidence has begun to reveal that Cdc20 and Cdh1 have opposing functions in tumorigenesis. Specifically, Cdh1 functions largely as a tumor suppressor, whereas Cdc20 exhibits an oncogenic function, suggesting that Cdc20 could be a promising therapeutic target for combating human cancer. However, the exact underlying molecular mechanisms accounting for their differences in tumorigenesis remain largely unknown. Therefore, in this review, we summarize the downstream substrates of Cdc20 and the critical functions of Cdc20 in cell cycle progression, apoptosis, ciliary disassembly and brain development. Moreover, we briefly describe the upstream regulators of Cdc20 and the oncogenic role of Cdc20 in a variety of human malignancies. Furthermore, we summarize multiple pharmacological Cdc20 inhibitors including TAME and Apcin, and their potential clinical benefits. Taken together, development of specific Cdc20 inhibitors could be a novel strategy for the treatment of human cancers with elevated Cdc20 expression.

NAHA, a novel hydroxamic acid-derivative, inhibits growth and angiogenesis of breast cancer in vitro and in vivo

Background

We have recently synthesized novel N-alkylated amino acid-derived hydroxamate, 2-[Benzyl-(2-nitro-benzenesulfonyl)-amino]-N-hydroxy-3-methyl-N-propyl-butyramide (NAHA). Here, we evaluate the anticancer activity of NAHA against highly invasive human breast cancer cells MDA-MB-231 in vitro and in vivo.

Methodology/Principal Findings

Cell growth was evaluated by MTT and soft agar assays. Protein expression was determined by DNA microarray and Western blot analysis. Metastatic potential was evaluated by cell adhesion, migration, invasion, capillary morphogenesis, and ELISA assays. The anticancer activity in vivo was evaluated in mouse xenograft model. NAHA inhibited proliferation and colony formation of MDA-MB-231 cells together with the down-regulation of expression of Cdk2 and CDC20 proteins. NAHA inhibited cell adhesion, migration, and invasion through the suppression of secretion of uPA. NAHA suppressed secretion of VEGF from MDA-MB-231 cells and inhibited capillary morphogenesis of human aortic endothelial cells (HAECs). Finally, NAHA at 50 mg/kg was not toxic and decreased tumor volume and tumor weight in vivo. This suppression of tumor growth was associated with the inhibition of mitotic figures and induction of apoptosis, and the reduction of CD31 and VEGF positive cells in tumors.

Conclusion

NAHA could be a novel promising compound for the development of new drugs for the therapy of invasive breast cancers.