Diseases are often caused by mutant proteins. Many drugs have limited effectiveness
and/or toxic side effects because of a failure to selectively target the disease-causing mutant variant,
rather than the functional wild type protein. Otherwise, the drugs may even target different
proteins with similar structural features. Designing drugs that successfully target mutant proteins
selectively represents a major challenge. Decades of cancer research have led to an abundance of
potential therapeutic targets, often touted to be “master regulators”. For many of these proteins,
there are no FDA-approved drugs available; for others, off-target effects result in dose-limiting
toxicity. Cancer-related proteins are an excellent medium to carry the story of mutant-specific targeting,
as the disease is both initiated and sustained by mutant proteins; furthermore, current
chemotherapies generally fail at adequate selective distinction. This review discusses some of the
challenges associated with selective targeting from a structural biology perspective, as well as some
of the developments in algorithm approach and computational workflow that can be applied to address
those issues. One of the most widely researched proteins in cancer biology is p53, a tumor suppressor.
Here, p53 is discussed as a specific example of a challenging target, with contemporary
drugs and methodologies used as examples of burgeoning successes. The oncogene KRAS, which
has been described as “undruggable”, is another extensively investigated protein in cancer biology.
This review also examines KRAS to exemplify progress made towards selective targeting of diseasecausing
mutant proteins. Finally, possible future directions relevant to the topic are discussed.