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Oxidoreductases have evolved over millions of years to perform a variety of metabolic tasks crucial for life. Understanding how these tasks are engineered relies on delivering external electron donors or acceptors to initiate electron transfer reactions. This is a challenge. Small-molecule redox reagents can act indiscriminately, poisoning the cell. Natural redox proteins are more selective, but finding the right partner can be difficult due to the limited number of redox potentials and difficulty tuning them.

DNA interstrand crosslinks (ICLs) pose a major obstacle for DNA replication and transcription if left unrepaired. The cellular response to ICLs requires the coordination of various DNA repair mechanisms. Homologous recombination (HR) intermediates generated in response to ICLs, require efficient and timely conversion by structure-selective endonucleases. Our knowledge on the precise coordination of this process remains incomplete. Here, we designed complementary genetic screens to map the machinery involved in the response to ICLs and identified FIRRM/C1orf112 as an indispensable factor in maintaining genome stability. FIRRM deficiency leads to hypersensitivity to ICL-inducing compounds, accumulation of DNA damage during S-G 2 phase of the cell cycle, and chromosomal aberrations, and elicits a unique mutational signature previously observed in HR-deficient tumors. In addition, FIRRM is recruited to ICLs, controls MUS81 chromatin loading, and thereby affects resolution of HR intermediates. FIRRM deficiency in mice causes early embryonic lethality and accelerates tumor formation. Thus, FIRRM plays a critical role in the response to ICLs encountered during DNA replication.

The high frequency of homologous recombination deficiency (HRD) is the main rationale of testing platinum-based chemotherapy in triple-negative breast cancer (TNBC), however, the existing methods to identify HRD are controversial and there is a medical need for predictive biomarkers. We assess the in vivo response to platinum agents in 55 patient-derived xenografts (PDX) of TNBC to identify determinants of response. The HRD status, determined from whole genome sequencing, is highly predictive of platinum response. BRCA1 promoter methylation is not associated with response, in part due to residual BRCA1 gene expression and homologous recombination proficiency in different tumours showing mono-allelic methylation. Finally, in 2 cisplatin sensitive tumours we identify mutations in XRCC3 and ORC1 genes that are functionally validated in vitro. In conclusion, our results demonstrate that the genomic HRD is predictive of platinum response in a large cohort of TNBC PDX and identify alterations in XRCC3 and ORC1 genes driving cisplatin response.

Tumor treating fields (TTFields), a new modality of cancer treatment, are electric fields transmitted transdermally to tumors. The FDA has approved TTFields for the treatment of glioblastoma multiforme and mesothelioma, and they are currently under study in many other cancer types. While antimitotic effects were the first recognized biological anticancer activity of TTFields, data have shown that tumor treating fields achieve their anticancer effects through multiple mechanisms of action. TTFields therefore have the ability to be useful for many cancer types in combination with many different treatment modalities. Here, we review the current understanding of TTFields and their mechanisms of action.

Supplementary Figure from The Mechanisms of Action of Tumor Treating Fields

Purpose We conducted a dose escalation Phase 1 study of autologous PBMCs loaded by microfluidic squeezing (Cell Squeeze® technology) with HPV16 E6 and E7 antigens (SQZ-PBMC-HPV), in HLA-A*02 + patients with advanced/metastatic HPV16 + cancers. Preclinical studies in murine models had shown such cells resulted in stimulation and proliferation of antigen specific CD8 + cells, and demonstrated antitumor activity. Methods Administration of SQZ-PBMC-HPV was every 3 weeks. Enrollment followed a modified 3 + 3 design with primary objectives to define safety, tolerability, and the recommended Phase 2 dose. Secondary and exploratory objectives were antitumor activity, manufacturing feasibility, and pharmacodynamic evaluation of immune responses. Results Eighteen patients were enrolled at doses ranging from 0.5 × 106to 5.0 × 106live cells/kg. Manufacture proved feasible and required 6live cells/kg with double priming was chosen as the recommended Phase 2 dose. Multiple participants exhibited pharmacodynamic changes consistent with immune responses supporting the proposed mechanism of action for SQZ-PBMC-HPV, including patients previously refractory to checkpoint inhibitors.

Background Our knowledge of changes in vegetation size throughout the course of infective endocarditis (IE) and the impact of persistent vegetations on mortality or embolization after completed antibiotic treatment is sparse. No study has previously investigated the prevalence or clinical impact of persistent vegetations on transthoracic echocardiography (TTE) at 6-months follow-up after ended IE treatment. Purpose To investigate the association between persistent vegetations at the 6-months TTE after treatment for IE and long-term prognosis as assessed in the POET trial. Methods The POET trial was a nationwide, multicenter RCT, randomizing 400 patients to either partial oral or intravenous (IV) antibiotic treatment of left-sided IE, after initial stabilization of infection using conventional IV therapy. A persistent vegetation was defined as a vegetation seen on 6-months follow-up TTE (4–7 months) after ended antibiotic treatment for IE. In the POET trial, primary outcome was defined as 1) all-cause mortality, 2) unplanned cardiac surgery, 3) embolic events or 4) relapse of bacteremia, in the 5-year follow-up period. Patients without TTE due to death or lack of available TTE were excluded. Results Out of 400 patients, 20 were excluded due to death during 6-months follow-up, and 201 were excluded due to unavailable TTE, leaving 179 TTEs for analysis. At 6-months follow-up, a persistent vegetation was seen in 30 patients (16.7%, 21 males (70%), mean age 69.6 years (SD 7.7)) (Table 1). Seventeen patients (56.7%) had a persistent vegetation on the aortic valve and 13 patients (43.3%) on the mitral valve. More patients without a persistent vegetation had undergone initial surgical treatment of IE than those with a vegetation (57.7 vs 23.3%, p=0.001). In all surgically treated patients with persistent vegetation at 6-months follow-up, the vegetation was found on another valve than the operated valve. The composite primary outcome from 6-months follow-up and until 5-year follow-up occurred in 8 patients (26.7%) with a persistent vegetation, compared to 38 patients (25.5%) (p=1.00) without. (Table 2) In patients randomized for peroral treatment, no significant difference in prevalence of persistent vegetation was found (15 patients (50%) with persistent vegetations vs. 74 patients (49.7%) without, p=1.00). Conclusion The occurrence of persistent vegetations at 6 months follow-up was 16.7%. There was no association between persistent vegetations at 6-months follow-up and the occurrence of the primary outcome after 5 years follow-up, suggesting that the risk associated with residual vegetations after end of antibiotic treatment is negligible after 6-months. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): The Danish Heart Foundation

New technologies for efficient solar-to-fuel energy conversion will help facilitate a global shift from dependence on fossil fuels to renewable energy. Nature uses photosynthetic reaction centers to convert photon energy into a cascade of electron-transfer reactions that eventually produce chemical fuel. The design of new reaction centers de novo deepens our understanding of photosynthetic charge separation and may one day allow production of biofuels with higher thermodynamic efficiency than natural photosystems. Recently, we described the multi-step electron-transfer activity of a designed reaction center maquette protein (the RC maquette), which can assemble metal ions, tyrosine, a Zn tetrapyrrole, and heme into an electron-transport chain. Here, we detail our modular strategy for rational protein design and show that the intended RC maquette design agrees with crystal structures in various states of assembly. A flexible, dynamic apo-state collapses by design into a more ordered holo-state upon cofactor binding. Crystal structures illustrate the structural transitions upon binding of different cofactors. Spectroscopic assays demonstrate that the RC maquette binds various electron donors, pigments, and electron acceptors with high affinity. We close with a critique of the present RC maquette design and use electron-tunneling theory to envision a path toward a designed RC with a substantially higher thermodynamic efficiency than natural photosystems.

Studies of nervous system effects of glyphosate, a widely used herbicide, have not been critically examined. The aim of this paper was to systematically review glyphosate-induced neurotoxicity literature to determine its usefulness in regulatory decision-making. The review was restricted to mammalian studies of behavior, neuropathology, and neuropharmacology

Aims: Recently, a novel isoform of anaplastic lymphoma kinase, with alternative transcription initiation (ALKATI ), has been described in melanoma and is susceptible to targeted ALK-inhibitor therapy. Clinical outcomes of patients with ALKATI mutated melanoma as well as correlation with immunohistochemical (IHC) methods has not yet been described. Methods and results: Clinicopathologic characteristics were abstracted for 324 patients with metastatic melanoma (MM). IHC, fluorescence in situ hybridization, and RNA based digital molecular analysis (NanoString Technologies) assays were performed on archival tissue from 173 stage III and 192 stage IV tumors. ALKATI was identified in 12.7% and 4.8% stage III and IV tumors, respectively. Discrete presentations of the ALKATI are seen: isolated ALKATI (N=20) and mixed ALKATI (combined ALKATI and ALKWT ; N=7). Isolated ALKWT expression (N=4) was seen with no ALK fusions. Stage III patients showed improved survival with ALKATI expression as compared to those with ALKWT or no expression [5-year survival 80% (95% CI: 57%-100%) versus 43% (95% CI: 34%-55%), p=0.013]. Clinicopathologic characteristics were not statistically significant. Strong diffuse cytoplasmic staining of ALK IHC (N=12), has a sensitivity of 52.2%, specificity 100%, PPV of 100% and NPV of 92.5% of detecting isolated ALKATI . Conclusion: Presence of ALKATI is a good prognostic indicator in MM. ALK IHC and digital molecular analysis can be incorporated into MM evaluation to identify patients with ALKATI for targeted therapy.

The rapid expansion of modern cancer immunotherapeutics has led to a dramatic improvement in patient survival and sustained remission for otherwise refractory malignancies. However, a significant limitation behind these current treatment modalities is an irregularity in clinical response, which is especially pronounced among checkpoint inhibition. This unpredictability leads to significant side effects, financial costs, and health care burden, with unsatisfactory clinical benefit in the majority of treated patients. Additionally, although ongoing studies and trials investigate the use of multiple biomarkers predictive of patient response or harm, none of these are comprehensive in predicting potential benefit. This unmet need for validated biomarkers is largely secondary to a prohibitive complexity within tumor parenchyma and microenvironment, dynamic clonal and proteomic changes to therapy, heterogenous host immune defects, and varied standardization among sample preparation and reporting. Herein, we discuss current advantages of predictive biomarkers, as well as limitations in their clinical use and application. We also review future directions, ideal characteristics, and trial design needed for proper precision immuno-oncology and biomarker development.

Natural photosynthetic protein complexes capture sunlight to power the energetic catalysis that supports life on Earth. Yet these natural protein structures carry an evolutionary legacy of complexity and fragility that encumbers protein reengineering efforts and obfuscates the underlying design rules for light-driven charge separation. De novo development of a simplified photosynthetic reaction center protein can clarify practical engineering principles needed to build new enzymes for efficient solar-to-fuel energy conversion. Here we report the rational design, X-ray crystal structure, and electron transfer activity of a multi-cofactor protein that incorporates essential elements of photosynthetic reaction centers. This highly stable, modular artificial protein framework can be reconstituted in vitro with interchangeable redox centers for nanometer-scale photochemical charge separation. Transient absorption spectroscopy demonstrates Photosystem II-like tyrosine and metal cluster oxidation, and we measure charge separation lifetimes exceeding 100 ms, ideal for light-activated catalysis. This de novo-designed reaction center builds upon engineering guidelines established for charge separation in earlier synthetic photochemical triads and modified natural proteins, and it shows how synthetic biology may lead to a new generation of genetically encoded, light-powered catalysts for solar fuel production.

Tumor treating fields (TTFields), a new modality of cancer treatment, are electric fields transmitted transdermally to tumors. The FDA has approved TTFields for the treatment of glioblastoma multiforme and mesothelioma, and they are currently under study in many other cancer types. While antimitotic effects were the first recognized biological anticancer activity of TTFields, data have shown that tumor treating fields achieve their anticancer effects through multiple mechanisms of action. TTFields therefore have the ability to be useful for many cancer types in combination with many different treatment modalities. Here, we review the current understanding of TTFields and their mechanisms of action.

Titanite U–Pb geochronology is a promising tool to date high-temperature tectonic processes, but the extent to and mechanisms by which recrystallization resets titanite U–Pb dates are poorly understood. This study combines titanite U–Pb dates, trace elements, zoning, and microstructures to directly date deformation and fluid-driven recrystallization along the Coast shear zone (BC, Canada). Twenty titanite grains from a deformed calc-silicate gneiss yield U–Pb dates that range from ~ 75 to 50 Ma. Dates between ~ 75 and 60 Ma represent metamorphic crystallization or inherited detrital cores, whereas ~ 60 and 50 Ma dates reflect localized, grain-scale processes that variably recrystallized the titanite. All the analyzed titanite grains show evidence of fluid-mediated dissolution–reprecipitation, particularly at grain rims, but lack evidence of thermally mediated volume diffusion at a metamorphic temperature of > 700 °C. The younger U–Pb dates are predominantly found in bent portions of grains or fluid-recrystallized rims. These features likely formed during ductile slip and associated fluid flow along the Coast shear zone, although it is unclear whether the dates represent 10 Myr of continuous recrystallization or incomplete resetting of the titanite U–Pb system during a punctuated metamorphic event. Correlations between dates and trace-element concentrations vary, indicating that the effects of dissolution–reprecipitation decoupled U–Pb dates from trace-element concentrations in some grains. These results demonstrate that U–Pb dates from bent titanite lattices and titanite subgrains may directly date crystal-plastic deformation, suggesting that deformation microstructures enhance fluid-mediated recrystallization, and emphasize the complexity of fluid and deformation processes within and among individual grains.

Background: Interleukin-12 (IL-12) is a potent proinflammatory cytokine with activating effects on both innate and adaptive immune cells. Though recombinant IL-12 (rIL-12) causes tumor regression with antitumor immune memory formation in a range of immunocompetent mouse models, clinical development of rIL-12 was limited by serious toxicities resulting in several patient deaths. WTX-330 is an engineered cytokine prodrug composed of a wild-type IL-12 heterodimer fused via proprietary cleavable linkers to an inactivation domain and to a half-life extension domain. In the circulation and in normal tissues, WTX-330 is designed to remain inactive and not bind to high-affinity IL-12 receptors. In contrast, proteolytic activation of WTX-330 in the tumor microenvironment is expected to liberate the IL-12 cytokine to stimulate antitumor immunity. Preclinical data show that WTX-330 is activated by a range of dissociated human tumors in vitro but not by normal human cells or by patient serum. Moreover, a WTX-330 murine surrogate molecule has potent antitumor activity as a monotherapy in multiple syngeneic mouse models, including in those resistant to anti-PD-1 therapy. In the MC38 model, the WTX-330 surrogate has a large therapeutic window of 49-fold compared to 5-fold for recombinant chimeric IL-12. Methods: This first-in-human, open-label phase 1 trial is investigating the safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity, and antitumor activity of WTX-330 administered as a monotherapy to patients with advanced or metastatic solid tumors or non-Hodgkin lymphoma (NCT05678998). All patients must have ≥ 1 measurable lesion per RECIST 1.1 and be refractory to all standard of care therapies for their indication. Dose escalation utilizes a Bayesian logistic regression model with overdose control with WTX-330 administered intravenously every two weeks in 28-day cycles. Dose expansion is anticipated to include two arms (A, B) of 20 patients each. Patients eligible for Arm A will have tumor types for which immune checkpoint inhibitors (ICIs) are indicated but demonstrate either primary or secondary resistance to this therapy. Primary resistance is defined as disease progression or SD < 6 months as the best response after at least 6 weeks of exposure to PD-(L)1 inhibitors. Secondary resistance is defined as disease progression ≥ 6 months after initiation of PD-(L)1 inhibitors in patients who received clinical benefit (i.e., CR, PR, or SD > 6 months). Patients eligible for Arm B will have any solid tumor for which ICI therapy is not indicated, or non-Hodgkin lymphoma. Pre- and on-treatment tumor biopsies, archival tumor tissue, and blood samples will be assayed for a range of exploratory biomarkers. As of January 12, 2023, the trial is opening sites and recruiting patients. Citation Format: Ildefonso Ismael Rodriguez-Rivera, Justin C. Moser, Mateusz Opyrchal, Aparna R. Parikh, Saero Park, Marissa Bruno, Paul Windt, Kulandayan K. Subramanian, Sameer S. Chopra, Randi Isaacs. Trial in progress: a first-in-human, phase 1, multicenter dose escalation and dose expansion study of WTX-330 in adult patients with advanced or metastatic solid tumors or non-Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT254.