In vivo CRISPR screens reveal Serpinb9 and Adam2 as regulators of immune therapy response in lung cancer.

How the genetic landscape governs a tumor's response to immunotherapy remains poorly understood. To assess the immune-modulatory capabilities of 573 genes associated with altered cytotoxicity in human cancers, here we perform CRISPR/Cas9 screens directly in mouse lung cancer models. We recover the known immune evasion factors Stat1 and Serpinb9 and identify the cancer testis antigen Adam2 as an immune modulator, whose expression is induced by KrasG12D and further elevated by immunotherapy. Using loss- and gain-of-function experiments, we show that ADAM2 functions as an oncogene by restraining interferon and TNF cytokine signaling causing reduced presentation of tumor-associated antigens. ADAM2 also restricts expression of the immune checkpoint inhibitors PDL1, LAG3, TIGIT and TIM3 in the tumor microenvironment, which might explain why ex vivo expanded and adoptively transferred cytotoxic T-cells show enhanced cytotoxic efficacy in ADAM2 overexpressing tumors. Together, direct in vivo CRISPR/Cas9 screens can uncover genetic alterations that control responses to immunotherapies.

Simultaneous inhibition of Sirtuin 3 and cholesterol homeostasis targets acute myeloid leukemia stem cells by perturbing fatty acid ß-oxidation and inducing lipotoxicity.

Outcomes for patients with acute myeloid leukemia (AML) remain poor due to the inability of current therapeutic regimens to fully eradicate disease-initiating leukemia stem cells (LSC). Previous studies have demonstrated that oxidative phosphorylation (OXPHOS) is an essential process that is targetable in LSC. Sirtuin 3 (SIRT3), a mitochondrial deacetylase with a multi-faceted role in metabolic regulation, has been shown to regulate OXPHOS in cancer models; however, it has not yet been studied in the context of LSC. Thus, we sought to identify if SIRT3 is important for LSC function. Using RNAi and a SIRT3 inhibitor (YC8-02), we demonstrate that SIRT3 is a critical target for the survival of primary human LSC but is not essential for normal human hematopoietic stem and progenitor cell function. In order to elucidate the molecular mechanisms by which SIRT3 is essential in LSC we combined transcriptomic, proteomic, and lipidomic approaches, showing that SIRT3 is important for LSC function through the regulation of fatty acid oxidation (FAO) which is required to support OXPHOS and ATP production in human LSC. Further, we discovered two approaches to further sensitize LSC to SIRT3 inhibition. First, we found that LSC tolerate the toxic effects of fatty acid accumulation induced by SIRT3 inhibition by upregulating cholesterol esterification. Disruption of cholesterol homeostasis sensitizes LSC to YC8-02 and potentiates LSC death. Second, SIRT3 inhibition sensitizes LSC to the BCL-2 inhibitor venetoclax. Together, these findings establish SIRT3 as a regulator of lipid metabolism and potential therapeutic target in primitive AML cells.

A noncoding single-nucleotide polymorphism at 8q24 drives IDH1-mutant glioma formation.

Establishing causal links between inherited polymorphisms and cancer risk is challenging. Here, we focus on the single-nucleotide polymorphism rs55705857, which confers a sixfold greater risk of isocitrate dehydrogenase (IDH)-mutant low-grade glioma (LGG). We reveal that rs55705857 itself is the causal variant and is associated with molecular pathways that drive LGG. Mechanistically, we show that rs55705857 resides within a brain-specific enhancer, where the risk allele disrupts OCT2/4 binding, allowing increased interaction with the Myc promoter and increased Myc expression. Mutating the orthologous mouse rs55705857 locus accelerated tumor development in an Idh1R132H-driven LGG mouse model from 472 to 172 days and increased penetrance from 30% to 75%. Our work reveals mechanisms of the heritable predisposition to lethal glioma in ~40% of LGG patients.

Clinical Use of an Electronic Pre-Visit Questionnaire Soliciting Patient Visit Goals and Interim History: A Retrospective Comparison Between Safety-net and Non-Safety-net Clinics.

INTRODUCTION/OBJECTIVES: We examined an initial step towards co-generation of clinic notes by inviting patients to complete a pre-visit questionnaire that could be inserted into clinic notes by providers and describe the experience in a safety-net and non-safety-net clinic. METHODS: We sent an electronic pre-visit questionnaire on visit goals and interim history to patients at a safety-net clinic and a non-safety-net clinic before clinic visits. We compared questionnaire utilization between clinics during a one-year period and performed a chart review of a sample of patients to examine demographics, content and usage of patient responses to the questionnaire. RESULTS: While use was low in both clinics, it was lower in the safety-net clinic (3%) compared to the non-safety-net clinic (10%). We reviewed a sample of respondents and found they were more likely to be White compared to the overall clinic populations (p < 0.05). There were no statistically significant differences in patient-typed notes (word count and number of visit goals) between the safety-net and non-safety-net samples however, patients at the safety-net clinic were less likely to have all of their goals addressed within the PCP documentation, compared to the non-safety-net clinic. CONCLUSIONS: Given potential benefits of this questionnaire as a communication tool, addressing barriers to use of technology among vulnerable patients is needed, including access to devices and internet, and support from caregivers or culturally concordant peer navigators.

Copper bioavailability is a KRAS-specific vulnerability in colorectal cancer.

Despite its importance in human cancers, including colorectal cancers (CRC), oncogenic KRAS has been extremely challenging to target therapeutically. To identify potential vulnerabilities in KRAS-mutated CRC, we characterize the impact of oncogenic KRAS on the cell surface of intestinal epithelial cells. Here we show that oncogenic KRAS alters the expression of a myriad of cell-surface proteins implicated in diverse biological functions, and identify many potential surface-accessible therapeutic targets. Cell surface-based loss-of-function screens reveal that ATP7A, a copper-exporter upregulated by mutant KRAS, is essential for neoplastic growth. ATP7A is upregulated at the surface of KRAS-mutated CRC, and protects cells from excess copper-ion toxicity. We find that KRAS-mutated cells acquire copper via a non-canonical mechanism involving macropinocytosis, which appears to be required to support their growth. Together, these results indicate that copper bioavailability is a KRAS-selective vulnerability that could be exploited for the treatment of KRAS-mutated neoplasms.

When Crises Converge: Hospital Visits Before And After Shelter Use Among Homeless New Yorkers.

People who are homeless use more hospital-based care than average, yet little is known about how hospital and shelter use are interrelated. We examined the timing of emergency department (ED) visits and hospitalizations relative to entry into and exit from New York City homeless shelters, using an analysis of linked health care and shelter administrative databases. In the year before shelter entry and the year following shelter exit, 39.3 percent and 43.3 percent, respectively, of first-time adult shelter users had an ED visit or hospitalization. Hospital visits-particularly ED visits-began to increase several months before shelter entry and declined over several months after shelter exit, with spikes in ED visits and hospitalizations in the days immediately before shelter entry and following shelter exit. We recommend cross-system collaborations to better understand and address the co-occurring health and housing needs of vulnerable populations.

Performance of PROMIS Global-10 Compared With Legacy Instruments for Rotator Cuff Disease.

BACKGROUND: The Patient-Reported Outcomes Measurement Information System (PROMIS) Global-10 was recently developed to assess physical and mental health and provide an estimated EuroQol-5 Dimension (EQ-5D) score. This instrument needs to be validated for specific patient cohorts such as those with rotator cuff pathology. HYPOTHESIS: There is moderate to high correlation between the PROMIS Global-10 and legacy patient-reported outcome measures; PROMIS Global-10 will not show ceiling effects; and estimated EQ-5D scores will show good correlation and low variance with actual EQ-5D scores. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: A total of 323 patients with rotator cuff disease were prospectively enrolled before treatment. Each patient completed the PROMIS Global-10, EQ-5D, American Shoulder and Elbow Surgeons (ASES) shoulder assessment form, and Single Assessment Numeric Evaluation (SANE), and those with known rotator cuff tears completed the Western Ontario Rotator Cuff Index (WORC). Spearman correlations were calculated. Bland-Altman agreement tests were conducted between estimated EQ-5D scores from the PROMIS and actual EQ-5D scores. Ceiling and floor effects were assessed, defined as ≥15% respondents with highest or lowest possible score. RESULTS: Correlation between the PROMIS Global-10 and EQ-5D was excellent (0.70, P < .0001). Correlation of the PROMIS physical scores was excellent-good with the ASES (0.62, P < .0001), good with the WORC (0.47, P < .0001), and good with the SANE (0.41, P < .0005). Correlation between the PROMIS mental scores was poor with the ASES (0.34, P < .0001), the WORC (0.32, P = .0016), and the SANE (0.24, P < .0001). No floor or ceiling effects were found. Agreement analysis showed substantial variance in individual scores, despite the overall similarity in mean scores between the estimated and actual EQ-5D scores, indicating poor agreement. Bland-Altman 95% limits of agreement for estimated EQ-5D scores ranged from 34% below to 31% above actual EQ-5D scores. CONCLUSION: Physical function scores of the PROMIS Global-10 show high correlation with legacy patient-reported outcome instruments, suggesting that it is a reliable tool for outcome assessment in a population with rotator cuff pathology. The large variability in 95% limit of agreement suggested that the estimated EQ-5D scores from the PROMIS Global-10 cannot replace traditional EQ-5D scores.

Predictors of Length of Stay and Discharge Disposition After Shoulder Arthroplasty: A Systematic Review.

INTRODUCTION: Identifying patient factors that affect length of stay (LOS) and discharge disposition after shoulder arthroplasty is key in managing patient expectations. In this systematic review, we identify patient-specific covariates that correlate with increased LOS and need for discharge to a facility. METHODS: We searched biomedical databases to identify associations between patient-specific factors and LOS and discharge disposition after shoulder arthroplasty. We included all studies involving hemiarthroplasty, anatomic shoulder arthroplasty, and reverse shoulder arthroplasty. Reported patient and provider factors were evaluated for their association with increased LOS and discharge to a facility. RESULTS: Twenty-two studies were identified. Age >65 years, female sex, obesity, and reverse shoulder arthroplasty were associated with extended LOS and correlated with discharge to a facility. Greater hospital and surgeon volume were associated with decreased LOS and decreased risk of discharge to a facility. Local injection of liposomal bupivacaine combined with intravenous dexamethasone was associated with reduced LOS. DISCUSSION: Patient factors affecting LOS and likelihood of discharge to a facility include age >65 years, female sex, diabetes, obesity, and reverse shoulder arthroplasty. These factors can be used to develop studies to preoperatively predict outcomes after shoulder arthroplasty and to help identify patients who may be at risk of prolonged postoperative admission. LEVEL OF EVIDENCE: Prognostic level IV.

Barriers to Early Hospital Discharge: A Cross-Sectional Study at Five Academic Hospitals.

BACKGROUND: Understanding the issues delaying hospital discharges may inform efforts to improve hospital throughput. OBJECTIVE: This study was conducted to identify and determine the frequency of barriers contributing to delays in placing discharge orders. DESIGN: This was a prospective, cross-sectional study. Physicians were surveyed at approximately 8:00 AM, 12:00 PM, and 3:00 PM and were asked to identify patients that were "definite" or "possible" discharges and to describe the specific barriers to writing discharge orders. SETTING: This study was conducted at five hospitals in the United States. PARTICIPANTS: The study participants were attending and housestaff physicians on general medicine services. PRIMARY OUTCOMES AND MEASURES: Specific barriers to writing discharge orders were the primary outcomes; the secondary outcomes included discharge order time for high versus low team census, teaching versus nonteaching services, and rounding style. RESULTS: Among 1,584 patient evaluations, the most common delays for patients identified as "definite" discharges (n = 949) were related to caring for other patients on the team or waiting to staff patients with attendings. The most common barriers for patients identified as "possible" discharges (n = 1,237) were awaiting patient improvement and for ancillary services to complete care. Discharge orders were written a median of 43-58 minutes earlier for patients on teams with a smaller versus larger census, on nonteaching versus teaching services, and when rounding on patients likely to be discharged first (all P < .003). CONCLUSIONS: Discharge orders for patients ready for discharge are most commonly delayed because physicians are caring for other patients. Discharges of patients awaiting care completion are most commonly delayed because of imbalances between availability and demand for ancillary services. Team census, rounding style, and teaching teams affect discharge times.

Regression and Genomic Analyses on the Association Between Dose-Normalized Mycophenolic Acid Exposure and Absolute Neutrophil Count in Steroid-Free, De Novo Kidney Transplant Recipients.

BACKGROUND AND OBJECTIVES: The hematological side effects associated with mycophenolic acid (MPA) are relatively common and have severe consequences. The majority of literature data have not shown clear consistency in the MPA exposure-neutropenia relationship. We hypothesized that (i) adult de novo kidney transplant recipients who develop neutropenia have relatively higher dose-normalized MPA exposure than patients without neutropenia, and (ii) the observed neutropenia may be explained by polymorphisms in metabolism and/or transporter genes responsible for MPA disposition. METHODS: Adult kidney transplant recipients on steady-state tacrolimus and MPA, not receiving a corticosteroid, and with stable renal function were recruited for investigation at three periods post-transplant (1, 3, and 12 months; n = 21, 17, and 13, respectively). Clinical variables (age, weight, MPA daily dose, albumin, serum creatinine, absolute neutrophil count), tacrolimus and MPA concentrations (for exposure calculation), and genotypes (UGT2B7 G211T, UGT2B7 C802T, UGT1A9 T-275A, UGT1A9 T98C, MRP2 C-24T, MRP2 G1249A, OATP1B1 A388G, OATP1B1 C463A) were characterized. RESULTS: A significant inverse association between dose-normalized MPA exposure (a surrogate marker for apparent MPA clearance) and absolute neutrophil count in all three study periods (r2 ~ 0.3-0.7) was observed. No associations between characterized single nucleotide polymorphisms and MPA exposure or absolute neutrophil count were established. However, significant alterations in the minor allele frequencies of UGT2B7*2 C802T, UGT1A9 T275A, and MRP2 G1249A were evident. CONCLUSION: These findings support the clinical strategy for conducting MPA therapeutic drug monitoring in adult kidney transplant patients on steroid-free immunosuppressant therapy. The novel population genomic analysis data warrant further epidemiological investigations in a larger study sample.

The ontogeny and population variability of human hepatic dihydronicotinamide riboside:quinone oxidoreductase (NQO2).

Dihydronicotinamide riboside:quinone oxidoreductase (NQO2) is an enzyme that performs reduction reactions involved in antioxidant defense. We hypothesized that NQO2 hepatic drug clearance would develop in children over time, similar to NQO1. Using human liver cytosol (n = 117), the effects of age, sex, ethnicity, and weight on NQO2 expression and activity were probed. No significant correlations were observed. Biochemical activity of NQO2 was as high at birth as in adults (0.23 ± 0.04 nmol/min/mg protein, mean ± SEM, range 0-1.83). In contrast, modeled hepatic clearance through the NQO2 pathway was up to 10% of adult levels at birth, reaching predicted adult levels (0.3 ± 0.03 L/h) at 14 years of age. Comparisons between NQO1 and NQO2 in the same livers showed that neither protein (P = 0.32) nor activity (P = 0.23) correlated, confirming both orthologs are independently regulated. Because hepatic clearance through NQO2 does not mature until teenage years, compounds detoxified by this enzyme may be more deleterious in children.

The Ontogeny and Population Variability of Human Hepatic NADPH Dehydrogenase Quinone Oxido-Reductase 1 (NQO1).

The NADPH dehydrogenase quinone oxido-reductase 1 (NQO1) enzyme is an antioxidant and metabolic enzyme that performs two electron reduction of quinones and other chemicals. Based on the physiologic role(s) of NQO1, we hypothesized that expression and activity of this enzyme would vary with age and other demographic variables. Cytosols from 117 archived human livers were investigated for changes in NQO1 with age, sex, obesity, and ethnicity. Protein expression but not activity of NQO1 was weakly negatively correlated with age (Spearman r = -0.2, P = 0.03). No sex differences were observed for either protein expression or activity and for ethnicity; Caucasians had greater NQO1 activity than Asians (P < 0.05). Overweight children had statistically significantly higher NQO1 activity as compared with ideal weight children (P < 0.05) although this difference was not observed in adults. These findings establish that NQO1 is approximately as active in children as adults. However, modeled NQO1 clearance (both allometric and physiologically based pharmacokinetics) predicted maturation at 23 to 26 years. This is almost certainly an overestimate, with error in the model resulting from a small sample size and inability to scale for age-related changes in hepatic cellularity and/or cytosolic protein content, and indicates a delay in reaching maximum clearance through the NQO1 pathway that is affected by physiologic development as much, or more than, biochemical development. Obesity may increase hepatic NQO1 activity in children, which is likely a protective mechanism in oxidative stress, but may also have significant implications for drug and chemical disposition in obese children.

ATP-binding cassette proteins BCRP, MRP1 and P-gp expression and localization in the human umbilical cord.

1. The umbilical cord is a direct conduit to the fetus hence transporters could have roles in partitioning substances between the maternal-placental-fetal units. Here we determined the expression and localization of the ATP-Binding Cassette (ABC) transporters BCRP (ABCG2), P-gp (ABCB1) and MRP1 (ABCC1) in human umbilical cords. 2. The mRNA for BCRP and MRP1 was detected in 25/25 samples, but P-gp was detected in only 5/25. ABC transporter mRNA expression relative to 18S was 25.6 ± 0.3, 26.5 ± 0.6 and 22.2 ± 0.2 cycles for BCRP, MRP1 and P-gp respectively. 3. Using a subset of 10 umbilical cords, BCRP protein was present in all samples (immunoblot) with positive correlation between mRNA and proteins (p = 0.07, r = 0.62) and between immunoblotting and immunohistochemistry (IHC) (p = 0.03, r = 0.67). P-gp protein was observed in 4/10 samples by both immunoblot and IHC, with no correlation between mRNA and protein (p = 0.45, r = 0.55) or immunoblotting and IHC (p = 0.2, r = 0.72), likely due to small sample size. MRP1 protein was not observed. 4. Localization of BCRP and P-gp proteins was to Wharton's jelly with no specific staining in arterial or venous endothelia. 5. Understanding ABC transporter expression in the umbilical cord may be useful for determining fetal exposures to xenobiotics if functional properties can be defined.