The cellular kinases inhibitory-κB kinase (IKK) α and Nuclear Factor-κB (NF-κB)-inducing kinase (NIK) are well recognised as key central regulators and drivers of the non-canonical NF-κB cascade and as such dictate the initiation and development of defined transcriptional responses associated with the liberation of p52-RelB and p52-p52 NF-κB dimer complexes. Whilst these kinases and downstream NF-κB complexes transduce pro-inflammatory and growth stimulating signals that contribute to major cellular processes, they also play a key role in the pathogenesis of a number of inflammatory-based conditions and diverse cancer types, which for the latter may be a result of background mutational status. IKKα and NIK, therefore, represent attractive targets for pharmacological intervention. Here, specifically in the cancer setting, we reflect on the potential pathophysiological role(s) of each of these kinases, their associated downstream signalling outcomes and the stimulatory and mutational mechanisms leading to their increased activation. We also consider the downstream coordination of transcriptional events and phenotypic outcomes illustrative of key cancer ‘Hallmarks’ that are now increasingly perceived to be due to the coordinated recruitment of both NF-κB-dependent as well as NF-κB–independent signalling. Furthermore, as these kinases regulate the transition from hormone-dependent to hormone-independent growth in defined tumour subsets, potential tumour reactivation and major cytokine and chemokine species that may have significant bearing upon tumour-stromal communication and tumour microenvironment it reiterates their potential to be drug targets. Therefore, with the emergence of small molecule kinase inhibitors targeting each of these kinases, we consider medicinal chemistry efforts to date and those evolving that may contribute to the development of viable pharmacological intervention strategies to target a variety of tumour types.

Probes based on Alkyne Tag Raman Imaging offer an entirely new platform for the sensing of pH _i .

Mitochondrial pH (pH_mito) is intimately related to mitochondrial function, and aberrant values for pH_mito are linked to several disease states. We report the design, synthesis, and application of mitokyne 1—the first small molecule pH_mito sensor for stimulated Raman scattering (SRS) microscopy. This ratiometric probe can determine subtle changes in pH_mito in response to external stimuli and the inhibition of both the electron transport chain and ATP synthase with small molecule inhibitors. In addition, 1 was also used to monitor mitochondrial dynamics in a time-resolved manner with subcellular spatial resolution during mitophagy providing a powerful tool for dissecting the molecular and cell biology of this critical organelle.

In 2004, we used NMR to solve the structure of the minor groove binder thiazotropsin A bound in a 2 : 1 complex to the DNA duplex, d(CGACTAGTCG)2. In this current work, we have combined theory and experiment to confirm the binding thermodynamics of this system. Molecular dynamics simulations that use polarizable or non-polarizable force fields with single and separate trajectory approaches have been used to explore complexation at the molecular level. We have shown that the binding process invokes large conformational changes in both the receptor and ligand, which is reflected by large adaptation energies. This is compensated for by the net binding free energy, which is enthalpy driven and entropically opposed. Such a conformational change upon binding directly impacts on how the process must be simulated in order to yield accurate results. Our MM-PBSA binding calculations from snapshots obtained from MD simulations of the polarizable force field using separate trajectories yield an absolute binding free energy (−15.4 kcal mol⁻¹) very close to that determined by isothermal titration calorimetry (−10.2 kcal mol⁻¹). Analysis of the major energy components reveals that favorable non-bonded van der Waals and electrostatic interactions contribute predominantly to the enthalpy term, whilst the unfavorable entropy appears to be driven by stabilization of the complex and the associated loss of conformational freedom. Our results have led to a deeper understanding of the nature of side-by-side minor groove ligand binding, which has significant implications for structure-based ligand development.