Kinases and Phosphatases

We have evaluated the quality of all 325 deposits in the PDB (as of December 2024) that correspond to (or contain) the catalytic domain of cAMP-dependent protein kinases (PKA). Detailed analysis was possible for 289 deposits of crystal structures that included not only the atomic coordinates but also structure factors. These structures represent 35 years of studies, and it is not surprising that the more recent structures are generally of better quality than the older ones. We did not encounter deposits with very severe problems, although some minor problems were found. To assess whether a uniform method of structure re-refinement, as implemented in the pipeline and website PDB-REDO, leads to significant improvement of structural models, we compared structure quality indicators for the originally refined structures and their counterparts resulting from PDB-REDO refinement. The re-refinement procedure significantly improved only some older structures, while its success was generally limited. We paid particular attention to the quality of small-molecule ligands, finding that most of them fit the electron density very well. This type of analysis helps identify the highest quality structures among many deposits for certain protein families and, thus, could be extended to other groups of proteins as well.

Digital twin is a mathematical model that virtually represents a physical object or process and predicts its behavior at future time points. These simulation models enable a deeper understanding of tumorigenic processes and improve biomarker discovery in cancer research. Tumor microenvironment is marked by dysregulated signaling pathways, where kinases and phosphatases serve as critical regulators and promising sources for biomarker discovery. These enzymes operate within multiscale and context-dependent processes where spatial and temporal coordination determine cellular outcomes. Digital Twin technology provides a platform for multimodal and multiscale modeling of kinase and phosphatase processes at the patient-specific level. These models have the potential to transform biomarker validation processes, enhance the prediction of therapeutic responses, and support precision decision-making. In this review, we present the major alterations affecting kinases and phosphatase functions within the tumor microenvironment and their clinical relevance as biomarkers, and we address how digital twins in oncology can augment and refine each stage of the biomarker discovery pipeline. Introducing this emerging technology for cancer biomarker discovery will assist in accelerating its adoption and translation into precision diagnostics and targeted therapies.

The first described instance of protein kinase activity dates back more than half a century [...]