RESUMEN
Recently, we characterized neoamphimedine (neo) as an ATP-competitive inhibitor of the ATPase domain of human Topoisomerase IIα. Thus far, neo is the only pyridoacridine with this mechanism of action. One limiting factor in the development of neo as a therapeutic agent has been access to sufficient amounts of material for biological testing. Although there are two reported syntheses of neo, both require 12 steps with low overall yields (≤6%). In this article, we report an improved total synthesis of neo achieved in 10 steps with a 25% overall yield. In addition, we report an expanded cytotoxicity study using a panel of human cancer cell lines, including: breast, colorectal, lung, and leukemia. Neo displays potent cytotoxicity (nM IC50 values) in all, with significant potency against colorectal cancer (lowest IC50 = 6 nM). We show that neo is cytotoxic not cytostatic, and that neo exerts cytotoxicity by inducing G2-M cell cycle arrest and apoptosis.
Asunto(s)
Acridinas/síntesis química , Acridinas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Inhibidores de Topoisomerasa II/síntesis química , Inhibidores de Topoisomerasa II/farmacología , Fosfatasa Ácida/metabolismo , Antígenos de Neoplasias/efectos de los fármacos , Antígenos de Neoplasias/metabolismo , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , ADN-Topoisomerasas de Tipo II/efectos de los fármacos , ADN-Topoisomerasas de Tipo II/metabolismo , Proteínas de Unión al ADN/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Fase G2/efectos de los fármacos , Humanos , Modelos Moleculares , Rodaminas/químicaRESUMEN
Metastasis is the cause of 90% of mortality in cancer patients. For metastatic colorectal cancer (mCRC), the standard-of-care drug therapies only palliate the symptoms but are ineffective, evidenced by a low survival rate of â¼11%. T-cell factor (TCF) transcription is a major driving force in CRC, and we have characterized it to be a master regulator of epithelial-mesenchymal transition (EMT). EMT transforms relatively benign epithelial tumor cells into quasi-mesenchymal or mesenchymal cells that possess cancer stem cell properties, promoting multidrug resistance and metastasis. We have identified topoisomerase IIα (TOP2A) as a DNA-binding factor required for TCF-transcription. Herein, we describe the design, synthesis, biological evaluation, and in vitro and in vivo pharmacokinetic analysis of TOP2A ATP-competitive inhibitors that prevent TCF-transcription and modulate or reverse EMT in mCRC. Unlike TOP2A poisons, ATP-competitive inhibitors do not damage DNA, potentially limiting adverse effects. This work demonstrates a new therapeutic strategy targeting TOP2A for the treatment of mCRC and potentially other types of cancers.