CFTR and colon carcinoma: While wefound that IOWH-032 is toxic against some commonly used human andmonkey host infection cell lines, the CFTR studies used differentcell lines, consisting mainly of human bronchial cells expressingdifferent variants of CFTR.22,65 Furthermore, IOWH-032is not toxic at micromolar concentrations in Chinese hamster ovary(CHO) cells expressing CFTR or colon carcinoma cells,35 illustrating that the presence of CFTR and the choice ofcell line are important considerations for selecting host cells forfuture infectivity experiments.