An antibiotic drug used to treat acne, among other things, may turn out to have potential well beyond that. Researchers from University of Antioquiain Medellin, Colombia, suggest that minocycline could be a promising antileukemic drug.
Minocycline is a well-established tetracycline derivative, used clinically since 1971, with a safe track record. But it also has nonantibiotic properties, exerting both antioxidant and antiapoptotic effects. There is even “compelling” preclinical evidence, the researchers say, that minocycline induces apoptosis in an acute myeloid leukemia cell line and a chronic myeloid leukemia cell line. Would the same be true of acute lymphoblastic leukemia (ALL) cells? To test their hypothesis, the researchers examined minocycline’s mechanism of action in the Jurkat cell line, an ALL tumor line established in the 1970s from the peripheral blood of a 14-year-old boy.
The researchers found that minocycline did in fact induce apoptosis in Jurkat cells through a hydrogen peroxide (H2O2)-mediated signaling pathway. Indeed, they add, H2O2 triggers a whole cascade of adverse effects, including up-regulation of pro-apoptotic proteins. The researchers suggest that minocycline might even be capable of generating H2O2, which could explain the cytotoxic effects not only of minocycline, but of other tetracycline analogues. “Interestingly,” the researchers say, minocycline did all that without inducing oxidative stress or apoptosis makers in human peripheral blood lymphocyte cells.
The significance of their study is twofold, the researchers say: First, that minocycline is a safe and specific apoptosis-inducing drug against Jurkat cells in vitro; second, that it is pharmacologically well characterized and widely available.
The researchers note that no information is available on whether minocycline might efficiently kill ALL cells in vivo. However, they also note that minocycline has been found to be safe and well tolerated in doses up to 10 mg/kg in stroke patients—a dose that could be a sufficient concentration to reduce the viability of leukemia cell lines.
Ruiz-Moreno C, Velez-Pardo C, Jimenez-Del-Rio M. Toxicol In Vitro. 2018;50:336-346.