No abstract

A chemokine receptor, CXCR4, and its endogenous ligand, stromal cell-derived factor-1 (SDF-1), have been recognized to be involved in the metastasis of several types of cancers. T140 analogs are peptidic CXCR4 antagonists composed of 14 amino acid residues that were previously developed as anti-HIV agents having inhibitory activity against HIV-entry through its co-receptor, CXCR4. Herein, we report that these compounds e¡ectively inhibited SDF-1-induced migration of human breast cancer cells (MDA-MB-231), human leukemia T cells (Sup-T1) and human umbilical vein endothelial cells at concentrations of 10^100 nM in vitro. Furthermore, slow release administration by subcutaneous injection using an Alzet osmotic pump of a potent and bio-stable T140 analog, 4F-benzoyl-TN14003, gave a partial, but statistically signi¢cant (P 9 9 0.05 (t-test)) reduction in pulmonary metastasis of MDA-MB-231 in SCID mice, even though no attempt was made to inhibit other important targets such as CCR7. These results suggest that T140 analogs have potential use for cancer therapy, and that small molecular CXCR4 antagonists could potentially replace neutralizing antibodies as anti-metastatic agents for breast cancer. ß

No abstract

A series of bicyclams have been shown to be potent and selective inhibitors of human immunodeficiency virus (HIV). The compounds are inhibitory to the replication of various HIV-1 and HIV-2 strains in various human T-cell systems, including peripheral blood lymphocytes, at 0.14-1.4 microM, without being toxic to the host cells at 2.2 mM. The bicyclam JM2763 is active against 3'-azido-3'-deoxythymidine (zidovudine; AZT)-resistant HIV-1 strains and acts additively with AZT. Mechanism of action studies revealed that the bicyclams (i.e., JM2763) interact with an early event of the retrovirus replicative cycle, which could be tentatively identified as a viral uncoating event.