Boron and Beyond: Where do we stand in cancer treatment?

Element boron(B) is in the IIIA group of the periodic table, with atom number 5 and a molecular weight of 10.81 mol/g. B is a rare element, and it involves many biological processes such as embryonic development, bone structure and function, oxidative stress, and, etc. Over the last decades, studies have shown that B-containing compounds regulate reactive oxygen species (ROS) levels, involve DNA damage mechanisms, and inhibit different enzymes. Improvements in medicine led researchers to think about B’s potential usage in cancer diagnosis, treatment, and prevention. Nowadays B-based compounds have been studied by different research groups on several types of cancer including prostate, lung, breast, colon, skin, brain, melanoma, etc. Studies revealed that B compounds can affect different types of cancers with different pathways/mechanisms. Based on the potential therapeutic effects of B, the first B-containing anticancer drug and a first-in-class proteasome inhibitor Bortezomib (Velcade®), was approved by the Food and Drug Administration (FDA) in 2003. On the other hand, boron neutron capture therapy (BNCT) is a very important clinical treatment for cancer which is based on B and B-containing delivery agents. During the past 20 years, researchers developed several new B delivery agents both for BNCT and B itself. In summary, this review article provides an overview of B compounds used for cancer diagnosis and treatment, delivery agents for BNCT, new therapeutic approaches containing B carriers, and novel B-based cancer detection approaches.