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Several observational studies suggested that gut microbiome-affecting-medication impairs the effectiveness of immunotherapy in patients with metastatic non-small-cell lung cancer (NSCLC). We postulated that if the effectiveness of immunotherapy is affected by drug-related changes of the microbiome, a stronger association between the use of co-medication and overall survival (OS) will be observed in patients treated with immunotherapy as compared to patients treated with chemotherapy. In a retrospective matched cohort study, immunotherapy patients were matched (1:1) to patients treated with chemotherapy in the pre immunotherapy era. The association between the use of antibiotics, opioids, proton pump inhibitors, metformin and other antidiabetics on OS was assessed with multivariable cox-regression analyses. Interaction tests were applied to investigate whether the association differs between patients treated with immuno- or chemotherapy. A total of 442 patients were studied. The use of antibiotics was associated with worse OS (adjusted Hazard Ratio (aHR) 1.39, p = 0.02) independent of the type of therapy (chemotherapy or immunotherapy). The use of opioids was also associated with worse OS (aHR 1.33, p = 0.01). The other drugs studied showed no association with OS. Interaction term testing showed no effect modification by immuno- or chemotherapy for the association of antibiotics and opioids with OS. The use of antibiotics and opioids is similarly associated with worse outcomes in both chemotherapy and immunotherapy treated NSCLC patients. This suggests that the association is likely to be a consequence of confounding rather than disturbing the composition of the microbiome. [ABSTRACT FROM AUTHOR]

We report the first identified mutation in the gene encoding human cytochrome c (CYCS). Glycine 41, invariant throughout eukaryotes, is substituted by serine in a family with autosomal dominant thrombocytopenia caused by dysregulated platelet formation. The mutation yields a cytochrome c variant with enhanced apoptotic activity in vitro. Notably, the family has no other phenotypic indication of abnormal apoptosis, implying that cytochrome c activity is not a critical regulator of most physiological apoptosis. [ABSTRACT FROM AUTHOR]

Recent discoveries in molecular diagnostics and drug treatments have improved the treatment of patients with advanced (inoperable) non-squamous non-small cell lung cancer (NSCLC) from solely platinum-based chemotherapy to more personalized treatment, including targeted therapies and immunotherapies. However, these improvements come at considerable costs, highlighting the need to assess their cost-effectiveness in order to optimize lung cancer care. Traditionally, cost-effectiveness models for the evaluation of new lung cancer treatments were based on the findings of the randomized control trials (RCTs). However, the strict RCT inclusion criteria make RCT patients not representative of patients in the real-world. Patients in RCTs have a better prognosis than patients in a real-world setting. Therefore, in this study, we developed and validated a diagnosis-treatment decision model for patients with advanced (inoperable) non-squamous NSCLC based on real-world data in the Netherlands. The model is a patient-level microsimulation model implemented as discrete event simulation with five health events. Patients are simulated from diagnosis to death, including at most three treatment lines. The base-model (non-personalized strategy) was populated using real-world data of patients treated with platinum-based chemotherapy between 2008 and 2014 in one of six Dutch teaching hospitals. To simulate personalized care, molecular tumor characteristics were incorporated in the model based on the literature. The impact of novel targeted treatments and immunotherapies was included based on published RCTs. To validate the model, we compared survival under a personalized treatment strategy with observed real-world survival. This model can be used for health-care evaluation of personalized treatment for patients with advanced (inoperable) NSCLC in the Netherlands. [ABSTRACT FROM AUTHOR]

Fundamentalunderstanding of protein–ligand interactionsis important to the development of efficient bioseparations in multimodalchromatography. Here we employ molecular dynamics (MD) simulationsto investigate the interactions of three different proteinsubiquitin,cytochrome C, and α-chymotrypsinogen A, sampling a range ofcharge from +1eto +9ewithtwo multimodal chromatographic ligands containing similar chemicalmoietiesaromatic, carboxyl, and amidein differentstructural arrangements. We use a spherical harmonic expansion toanalyze ligand and individual moiety density profiles around the proteins.We find that the Capto MMC ligand, which contains an additional aliphaticgroup, displays stronger interactions than Nuvia CPrime ligand withall three proteins. Studying the ligand densities at the moiety levelsuggests that hydrophobic interactions play a major role in determiningthe locations of high ligand densities. Finally, the greater structuralflexibility of the Capto MMC ligand compared to that of the NuviacPrime ligand allows for stronger structural complementarity and enablesstronger hydrophobic interactions. These subtle and not-so-subtledifferences in binding affinities and modalities for multimodal ligandscan result in significantly different binding behavior towards proteinswith important implications for bioprocessing. [ABSTRACT FROM AUTHOR]

B Correction: BMC Medical Research Methodology 23, 1 (2023) b B https://doi.org/10.1186/s12874-022-01760-0 b Following publication of the original article [[1]], the authors requested to correct the word "first-line" to "second-line" in the article title. Reference 1 Ismail RK, Schramel FMNH, van Dartel M. Individual patient data to allow a more elaborated comparison of trial results with real-world outcomes from first-line immunotherapy in NSCLC. [Extracted from the article]

A lysozyme library was employed to study the effects of protein surface modification on protein retention and to elucidate preferred protein binding orientations for cation exchange chromatography. Acetic anhydride was used as an acetylating agent to modify protein surface lysine residues. Partial acetylation of lysozyme resulted in the formation of a homologous set of modified proteins with varying charge densities and distribution. The resulting protein charge ladder was separated on a cation exchange column, and eluent fractions were subsequently analyzed using capillary zone electrophoresis and direct infusion electrospray ionization mass spectrometry. The ion exchange separation showed a significant degree of variation in the retention time of the different variants. Several fractions contained coelution of variants, some with differing net charge. In addition, several cases were observed where variants with more positive surface charge eluted from the column prior to variants with less positive charge. Enzymatic digest followed by mass spectrometry was performed to determine the sites of acetylation on the surface of the variants eluting in various fractions. Electrostatic potential maps of these variants were then generated to provide further insight into the elution order of the variants. [ABSTRACT FROM AUTHOR]

We describe an affinity-based strategy for designing selective protein displacers for the chromatographic purification of proteins. To design a displacer that is selective for a target protein, we attached a component with affinity for the target protein to a resin-binding component; we then tested the ability of such displacers to selectively retain the target protein on a resin relative to another protein having a similar retention time. In particular, we synthesized displacers based on biotin, which selectively retained avidin as compared to aprotinin on SP Sepharose high performance resin. In addition, we have extended this approach to develop an affinity-peptide-based displacer that discriminates between lysozyme and cytochrome c. Here, a selective displacer was designed from a lysozyme-binding peptide that had been identified and optimized previously using phage-display technology. Our results suggest a general strategy for designing highly selective affinity-based displacers by identifying molecules (e.g., peptides) that bind to a protein of interest and using an appropriate linker to attach these molecules to a moiety that binds to the stationary phase. [ABSTRACT FROM AUTHOR]