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Multiple myeloma (MM) is a hematological malignancy that emerges from antibody-producing plasma B cells. Proteasome inhibitors, including the FDA-approved bortezomib (BTZ) and carfilzomib (CFZ), are frequently used for the treatment of MM patients. Still, a significant proportion of MM patients are refractory or develop resistance to this class of inhibitors, which represents a significant challenge in the clinic. Thus, identifying factors that determine the potency of proteasome inhibitors in MM is of paramount importance to bolster their efficacy in the clinic. Using genome-wide CRISPR-based screening, we identified a subunit of the mitochondrial pyruvate carrier (MPC) complex, MPC1, as a common modulator of BTZ response in two distinct human MM cell lines in vitro. We noticed that CRISPR-mediated deletion or pharmacological inhibition of the MPC complex enhanced BTZ/CFZ-induced MM cell death with minimal impact on cell cycle progression. In fact, targeting the MPC complex compromised the bioenergetic capacity of MM cells, which is accompanied by a reduced proteasomal activity, thereby exacerbating BTZ-induced cytotoxicity in vitro. Importantly, we observed that the RNA expression levels of several players in pyruvate metabolism were altered in advanced stages of MM wherein they correlated with poor prognosis for MM patients. Collectively, this study highlights the importance of the MPC complex for the survival of MM cells and their responses to proteasome inhibitors. These findings establish mitochondrial pyruvate metabolism as a potential target for the treatment of MM, and a hitherto unappreciated strategy to increase the efficacy of proteasome inhibitors in the clinic.

The heterochromatin protein HP1 plays a central role in the maintenance of genome stability but little is known about how HP1 is controlled. Here, we show that the zinc finger protein POGZ promotes the presence of HP1 at DNA double‐strand breaks (DSBs) in human cells. POGZ depletion delays the resolution of DSBs and sensitizes cells to different DNA‐damaging agents, including cisplatin and talazoparib. Mechanistically, POGZ promotes homology‐directed DNA repair by retaining the BRCA1/BARD1 complex at DSBs in an HP1‐dependent manner. In vivo CRISPR inactivation of Pogz is embryonically lethal. Pogz haploinsufficiency (Pogz(+)/delta) results in developmental delay, impaired intellectual abilities, hyperactive behaviour and a compromised humoral immune response in mice, recapitulating the main clinical features of the White Sutton syndrome (WHSUS). Pogz(+)/delta mice are further radiosensitive and accumulate DSBs in diverse tissues, including the spleen and brain. Altogether, our findings identify POGZ as an important player in homology‐directed DNA repair both in vitro and in vivo.

BackgroundImaging tests are one of the most frequently used diagnostic modalities in healthcare, but the benefits of their direct impacts on clinical decision-making have been countered by concerns that they can be overused. Assessing the relative value of imaging tests has largely focused on measures of test accuracy, which overlooks more comprehensive benefits and risks of imaging tests, particularly their impact on patient-centred outcomes (PCOs). We present the findings of the Patient Reported Outcomes of Diagnostics (PROD) research study in response to a methodological gap in the area of diagnostic test comparative effectiveness research.MethodsOver a 3-year period, the PROD Study engaged with multiple stakeholders to identify existing conceptual models related to PCOs for imaging testing, conducted primary research and evidence synthesis, and developed consensus recommendations to describe and categorise PCOs related to imaging testing.ResultsThe PROD framework categorises PCOs from imaging studies within four main domains: information or knowledge yielded, physical impact, emotional outcomes and test burden. PCOs interact with each other and influence effects across domains, and can be modified by factors related to the patient, clinical situation, healthcare team and the testing environment.ConclusionsUsing PCOs to inform healthcare decision-making will require ways of collating and presenting information on PCOs in ways that can inform patient–provider decision-making, and developing methods to determine the relative importance of outcomes (including test accuracy) to one another.

The homologous recombination repair (HRR) pathway repairs DNA double-strand breaks in an error-free manner. Mutations in HRR genes can result in increased mutation rate and genomic rearrangements, and are associated with numerous genetic disorders and cancer. Despite intensive research, the HRR pathway is not yet fully mapped. Phylogenetic profiling analysis, which detects functional linkage between genes using coevolution, is a powerful approach to identify factors in many pathways. Nevertheless, phylogenetic profiling has limited predictive power when analyzing pathways with complex evolutionary dynamics such as the HRR. To map novel HRR genes systematically, we developed clade phylogenetic profiling (CladePP). CladePP detects local coevolution across hundreds of genomes and points to the evolutionary scale (e.g., mammals, vertebrates, animals, plants) at which coevolution occurred. We found that multiscale coevolution analysis is significantly more biologically relevant and sensitive to detect gene function. By using CladePP, we identified dozens of unrecognized genes that coevolved with the HRR pathway, either globally across all eukaryotes or locally in different clades. We validated eight genes in functional biological assays to have a role in DNA repair at both the cellular and organismal levels. These genes are expected to play a role in the HRR pathway and might lead to a better understanding of missing heredity in HRR-associated cancers (e.g., heredity breast and ovarian cancer). Our platform presents an innovative approach to predict gene function, identify novel factors related to different diseases and pathways, and characterize gene evolution.

The heterochromatin protein HP1 plays a central role in the maintenance of genome stability, in particular by promoting homologous recombination (HR)-mediated DNA repair. However, little is still known about how HP1 is controlled during this process. Here, we describe a novel function of the POGO transposable element derived with ZNF domain protein (POGZ) in the regulation of HP1 during the DNA damage response in vitro. POGZ depletion delays the resolution of DNA double-strand breaks (DSBs) and correlates with an increased sensitivity to different DNA damaging agents, including the clinically-relevant Cisplatin and Talazoparib. Mechanistically, POGZ promotes homology-directed DNA repair pathways by retaining the BRCA1/BARD1 complex at DSBs, in a HP1-dependent manner. In vivo CRISPR inactivation of Pogz is embryonically lethal and Pogz haplo-insufficiency (Pogz+/Δ) results in a developmental delay, impaired intellectual abilities, a hyperactive behaviour as well as a compromised humoral immune response in mice, recapitulating the main clinical features of the White Sutton syndrome (WHSUS). Importantly, Pogz+/Δ mice are radiosensitive and accumulate DSBs in diverse tissues, including the spleen and the brain. Altogether, our findings identify POGZ as an important player in homology-directed DNA repair both in vitro and in vivo, with clinical implications for the WHSUS.

Background: Imaging tests are a widely used tool in primary care with many known benefits. Without an understanding of which outcomes matter the most to patients, clinicians are challenged to balance the benefits and harms of imaging tests. This study aimed to explore the perceived impacts imaging tests have on patients from the perspective of the primary care providers (PCPs) and determine PCPs9 understanding of patient-centered outcomes (PCOs) from imaging tests. Methods: Recruitment of PCPs occurred at 4 family medicine clinics in Washington and Idaho. Primary care physicians, nurse practitioners, or physician assistants who order imaging tests were eligible to participate. Semistructured interviews explored providers9 perceptions of patient experiences during the process of ordering, performing and following up on imaging tests. Classic content analysis generated themes and subthemes. Results: Sixteen PCPs, including 11 physicians, 3 physician assistants, and 2 nurse practitioners, completed interviews. Two themes were identified: 1) perceived PCOs, and 2) factors influencing the incorporation of PCOs into clinical management. Perceived outcomes included emotions related to the answer a test provides and costs to the patient such as monetary, physical, and added risk. Patient expectations, provider-patient communication, and inadequate knowledge all contributed as barriers to incorporating PCOs into clinical management. Discussion: PCPs recognize different outcomes of imaging tests that they consider important for patients. While providers are perceptive to patient outcomes there remains a challenge to how patient outcomes are used to improve care. Communication with patients and improving provider knowledge are needed to incorporate identified PCOs.

DNA double‐strand breaks (DSBs) can be repaired by two major pathways: non‐homologous end‐joining (NHEJ) and homologous recombination (HR). DNA repair pathway choice is governed by the opposing activities of 53BP1, in complex with its effectors RIF1 and REV7, and BRCA1. However, it remains unknown how the 53BP1/RIF1/REV7 complex stimulates NHEJ and restricts HR to the S/G2 phases of the cell cycle. Using a mass spectrometry (MS)‐based approach, we identify 11 high‐confidence REV7 interactors and elucidate the role of SHLD2 (previously annotated as FAM35A and RINN2) as an effector of REV7 in the NHEJ pathway. FAM35A depletion impairs NHEJ‐mediated DNA repair and compromises antibody diversification by class switch recombination (CSR) in B cells. FAM35A accumulates at DSBs in a 53BP1‐, RIF1‐, and REV7‐dependent manner and antagonizes HR by limiting DNA end resection. In fact, FAM35A is part of a larger complex composed of REV7 and SHLD1 (previously annotated as C20orf196 and RINN3), which promotes NHEJ and limits HR. Together, these results establish SHLD2 as a novel effector of REV7 in controlling the decision‐making process during DSB repair.

SUMMARYDNA double-strand breaks (DSBs) can be repaired by two major pathways: non-homologous end-joining (NHEJ) and homologous recombination (HR). DNA repair pathway choice is governed by the opposing activities of 53BP1, in complex with its effectors RIF1 and REV7, and BRCA1. However, it remains unknown how the 53BP1/RIF1/REV7 complex stimulates NHEJ and restricts HR to the S/G2 phases of the cell cycle. Using a mass spectrometry (MS)-based approach, we identify 11 high-confidence REV7 interactors and elucidate the role of a previously undescribed factor, FAM35A/SHDL2, as a novel effector of REV7 in the NHEJ pathway. FAM35A depletion impairs NHEJ-mediated DNA repair and compromises antibody diversification by class switch recombination (CSR) in B-cells. FAM35A accumulates at DSBs in a 53BP1-, RIF1- and REV7-dependent manner and antagonizes HR by limiting DNA end resection. In fact, FAM35A is part of a larger complex composed of REV7 and another previously uncharacterized protein, C20orf196/SHDL1, which promotes NHEJ and limits HR. Together, these results establish FAM35A as a novel effector of REV7 in controlling the decision-making process during DSB repair.

The growth in mass media drug advertising has coincided with a rapid rise in spending on prescription drugs in the United States. Our research examines the potential link between increased ad spending and the rising use and sale of these drugs. We found strong circumstantial evidence that ad spending is one of many important elements driving the sharp rise in pharmaceutical sales to consumers.

The efficacy and safety of nedocromil sodium inhalation aerosol (4 mg of Tilade administered by metered-dose inhaler) given twice daily was compared with placebo in 112 patients with mild-to-moderate asthma who had been receiving maintenance therapy with oral or inhaled bronchodilators or both. After a 2-week run-in period and a subsequent 2-week baseline period, patients were randomized to active treatment (n = 56) or placebo (n = 56) for 8 weeks. All maintenance bronchodilators were withdrawn before the baseline period, and patients entered the treatment period only after demonstrating a specified level of asthma symptoms. Twice daily administration of nedocromil sodium improved all asthma symptoms in these patients who had symptoms as a result of the withdrawal of their maintenance theophylline and/or oral and inhaled beta 2-agonist bronchodilators. During the primary time period (treatment weeks 5 to 8), statistically significant between-group differences favored nedocromil sodium for the asthma summary score (primary variable, p = 0.001), daytime asthma (p = 0.001), and sleep difficulty caused by asthma (p = 0.006). Furthermore, significant reductions in the use of as-needed rescue medications were reported in the nedocromil sodium group (p = 0.003) compared with the placebo group. Final overall opinions of treatment effectiveness expressed by physicians (p = 0.016) and patients (p = 0.002) strongly favored nedocromil sodium.