Spontaneously-forming spheroids as an in vitro cancer cell model for anticancer drug screening.
Oncotarget 2016;
6:21255-67. [PMID:
26101913 PMCID:
PMC4673263 DOI:
10.18632/oncotarget.4013]
[Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 06/08/2015] [Indexed: 12/12/2022] Open
Abstract
The limited translational value in clinic of analyses performed on 2-D cell cultures has prompted a shift toward the generation of 3-dimensional (3-D) multicellular systems. Here we present a spontaneously-forming in vitro cancer spheroid model, referred to as spheroidsMARY-X, that precisely reflects the pathophysiological features commonly found in tumor tissues and the lymphovascular embolus. In addition, we have developed a rapid, inexpensive means to evaluate response following drug treatment where spheroid dissolution indices from brightfield image analyses are used to construct dose-response curves resulting in relevant IC50 values. Using the spheroidsMARY-X model, we demonstrate the unique ability of a new class of molecules, containing the caged Garcinia xanthone (CGX) motif, to induce spheroidal dissolution and apoptosis at IC50 values of 0.42 +/−0.02 μM for gambogic acid and 0.66 +/−0.02 μM for MAD28. On the other hand, treatment of spheroidsMARY-X with various currently approved chemotherapeutics of solid and blood-borne cancer types failed to induce any response as indicated by high dissolution indices and subsequent poor IC50 values, such as 7.8 +/−3.1 μM for paclitaxel. Our studies highlight the significance of the spheroidsMARY-X model in drug screening and underscore the potential of the CGX motif as a promising anticancer pharmacophore.
Collapse