The deubiquitinating enzyme USP7 regulates the transcription factor Nrf1 by modulating its stability in response to toxic metal exposure.

The nuclear factor E2-related factor 1 (Nrf1) transcription factor performs a critical role in regulating cellular homeostasis as part of the cellular stress response and drives the expression of antioxidants and detoxification enzymes among many other functions. Ubiquitination plays an important role in controlling the abundance and thus nuclear accumulation of Nrf1 proteins, but the regulatory enzymes that act on Nrf1 are not fully defined. Here, we identified ubiquitin specific protease 7 (USP7), a deubiquitinating enzyme, as a novel regulator of Nrf1 activity. We found that USP7 interacts with Nrf1a and TCF11-the two long protein isoforms of Nrf1. Expression of wildtype USP7, but not its catalytically defective mutant, resulted in decreased ubiquitination of TCF11 and Nrf1a, leading to their increased stability and increased transactivation of reporter gene expression by TCF11 and Nrf1a. In contrast, knockdown or pharmacologic inhibition of USP7 dramatically increased ubiquitination of TCF11 and Nrf1a and reduction of their steady state levels. Loss of USP7 function attenuated the induction of Nrf1 protein expression in response to treatment with arsenic and other toxic metals, and inhibition of USP7 activity significantly sensitized cells to arsenic treatment. Collectively, these findings suggest that USP7 may act to modulate abundance of Nrf1 protein to induce gene expression in response to toxic metal exposure.

A Nonconserved Histidine Residue on KRAS Drives Paralog Selectivity of the KRASG12D Inhibitor MRTX1133.

MRTX1133 is the first noncovalent inhibitor against the KRASG12D mutant that demonstrated specificity and potency in preclinical tumor models. Here, we used isogenic cell lines expressing a single RAS allele to evaluate the selectivity of this compound. In addition to KRASG12D, MRTX1133 showed significant activity against several other KRAS mutants as well as wild-type KRAS protein. In contrast, MRTX1133 exhibited no activity against both G12D and wild-type forms of HRAS and NRAS proteins. Functional analysis revealed that the selectivity of MRTX1133 toward KRAS is associated with its binding to H95 on KRAS, a residue that is not conserved in HRAS and NRAS. Reciprocal mutation of amino acid 95 among the three RAS paralogs resulted in reciprocal change in their sensitivity toward MRTX1133. Thus, H95 is an essential selectivity handle for MRTX1133 toward KRAS. Amino acid diversity at residue 95 could facilitate the discovery of pan-KRAS inhibitors as well as HRAS and NRAS paralog-selective inhibitors. SIGNIFICANCE: The nonconserved H95 residue on KRAS is required for the selectivity of the KRASG12D inhibitor MRTX1133 and can be exploited for the development of pan-KRAS inhibitors.

Long-term Use of Wearable Health Technology by Chronic Pain Patients.

OBJECTIVES: People living with chronic pain may use wearable health technology (WHT) in conjunction with an expert-directed pain management program for up to 1 year. WHT use may be associated with improvements in key patient outcomes. METHODS: A 12-month study of WHT use among people with chronic pain was conducted, consisting of iPhone and Apple Watch applications to measure movement, sleep, and self-reported pain. Clinical outcomes among 105 patients enrolled in a multidisciplinary pain program that included WHT use were compared with 146 patients in the same program but without WHT, and to 161 patients receiving medical pain management without WHT. RESULTS: Participants used the WHT on average 143.0 (SD: 117.6) out of 365 days. Mixed-effects models revealed participants who used WHT had decreases in depression scores (-7.83, P <0.01) and prescribed morphine milligram equivalents (-21.55, P =0.04) over 1 year. Control groups also showed decreases in depression scores (-5.08, P =0.01; -5.68, P <0.01) and morphine milligram equivalents (-18.67, P =0.01; -10.99, ns). The estimated slope of change among the WHT was not statistically different than control groups. DISCUSSION: Patients who used WHT as part of their pain management program demonstrated a willingness to do so for extended periods of time despite living with chronic pain and other comorbidities. Data trends suggest that WHT use may positively impact depression and prescribed medication. Additional research is warranted to investigate the potential of WHT to improve the negative consequences of chronic pain.

The Nrf1 transcription factor is induced by patulin and protects against patulin cytotoxicity.

Patulin is a mycotoxin produced by a variety of molds that is found in various food products. The adverse health effects associated with exposure to patulin has led to many investigations into the biological basis driving the toxicity of patulin. Nevertheless, the mechanisms through which mammalian cells resists patulin-mediated toxicity is poorly understood. Here, we show that loss of the Nrf1 transcription factor renders cells sensitive to the acute cytotoxic effects of patulin. Nrf1 deficiency leads to accumulation of ubiquitinated proteins and protein aggregates in response to patulin exposure. Nrf1 expression is induced by patulin, and activation of proteasome genes by patulin is Nrf1-dependent. These findings suggest the Nrf1 transcription factor plays a crucial role in modulating cellular stress response against patulin cytotoxicity.

Genetics and prescription opioid use (GaPO): study design for consenting a cohort from an existing biobank to identify clinical and genetic factors influencing prescription opioid use and abuse.

BACKGROUND: Prescription opioids (POs) are commonly used to treat moderate to severe chronic pain in the health system setting. Although they improve quality of life for many patients, more work is needed to identify both the clinical and genetic factors that put certain individuals at high risk for developing opioid use disorder (OUD) following use of POs for pain relief. With a greater understanding of important risk factors, physicians will be better able to identify patients at highest risk for developing OUD for whom non-opioid alternative therapies and treatments should be considered. METHODS: We are conducting a prospective observational study that aims to identify the clinical and genetic factors most stongly associated with OUD. The study design leverages an existing biobank that includes whole exome sequencing and array genotyping. The biobank is maintained within an integrated health system, allowing for the large-scale capture and integration of genetic and non-genetic data. Participants are enrolled into the health system biobank via informed consent and then into a second study that focuses on opioid medication use. Data capture includes validated self-report surveys measuring addiction severity, depression, anxiety, and nicotine use, as well as additional clinical, prescription, and brain imaging data extracted from electronic health records. DISCUSSION: We will harness this multimodal data capture to establish meaningful patient phenotypes in order to understand the genetic and non-genetic contributions to OUD.

Nicotinic acetylcholine receptor genes on chromosome 15q25.1 are associated with nicotine and opioid dependence severity.

A locus on chromosome 15q25.1 previously implicated in nicotine, alcohol, and cocaine dependence, smoking, and lung cancer encodes subunits of the nicotinic acetylcholine receptor (nAChR) expressed in the mesolimbic system and thought to mediate substance dependence. Opioid dependence severity (ODS), nicotine dependence severity (NDS), smoking status and quantity, and the number of attempts to quit were assessed using questionnaire instruments in 505 subjects who were prescribed opioid medications for chronic pain in outpatient practice sites. Multivariate regression was used to test for genetic association of these phenotypes with 5 SNPs in the nAChR gene cluster on chromosome 15q25.1, adjusting for background variables. A coding variant in CHRNA5 (rs16969968[A]) was significantly associated with 1.4-unit higher ODS (p < 0.00017). A variant in the 3' untranslated region of CHRNA3 (rs660652[G]) was significantly associated with 1.7-fold higher odds of lifetime smoking (p < 0.0092), 1.1-unit higher NDS (p < 0.0007), 0.7 more pack-years of cigarette smoking (p < 0.0038), and 0.8 more lifetime attempts to quit (p < 0.0084). Our data suggest an association of DNA variants in the nAChR gene cluster on chromosome 15q25.1 with ODS, as well as NDS and related smoking phenotypes. While the association of this locus with NDS and smoking phenotypes is well known, the association with ODS, a dimension of opioid substance dependence, is novel and requires verification in independent studies.

Impact of a multidisciplinary pain management program on patient care utilization and cost of care.

OBJECTIVE: Chronic pain is a highly prevalent and costly condition with few proven treatment options. Since 2014, Geisinger's Department of Pain Medicine has implemented the Multidisciplinary Pain Program (MPP), which consists of a 3-day educational seminar followed by 12 months of comprehensive care. This study examines the impact of MPP on care utilization and cost between 2014 and 2016. METHODS: A retrospective health insurance claims data analysis covering a 3-year period between January 2013 and December 2016. Among all patients referred to MPP during the period, a subset of those who were Geisinger Health Plan (GHP) members was identified (113 patients). Those who were GHP members and were referred to MPP after December 2016 served as the contemporaneous comparison group (69 patients). GHP's claims data for the corresponding period were analyzed on a per-member-per-month (PMPM) basis. RESULTS: MPP was associated with US$754 PMPM reduction in total cost of care including prescription drug costs (P=0.014) and US$846 reduction in total medical cost excluding prescription drugs (P=0.006). These cost savings were attributable to reductions in utilization of high-end diagnostic imaging (52 per-1,000 members-per month; P=0.015) and acute inpatient admissions (20 per-1,000 members-per month; P=0.086). CONCLUSION: Patients enrolled in MPP were less likely to use expensive diagnostic imaging and experienced fewer hospitalizations, resulting in total cost of care savings. These findings are consistent with the expectation that MPP improves health outcomes among patients suffering from chronic pain.

Patterns of health care utilization and cost before and after opioid overdose: findings from 10-year longitudinal health plan claims data.

OBJECTIVE: To describe the longitudinal pattern of health care utilization and cost of care before and after opioid overdose (OD) over a 10-year period using health plan claims data. METHODS: Patients who had experienced opioid ODs between April 2005 and March 2015 were identified from Geisinger Health System's electronic health records. Among these patients, a subgroup of patients who were Geisinger Health Plan (GHP) members at any point between January 2006 and December 2015 were also identified. From the corresponding GHP claims data, their all-cause health care utilization (inpatient admissions, emergency department [ED] visits, and physician office visits) and total medical costs, excluding prescription medication cost, were obtained. Per-member-per-month estimates for each month before and after the index date of opioid OD were calculated, adjusting for age, gender, plan type, year, and comorbidity via multivariate regression models. RESULTS: A total of 942 opioid OD patients with an average GHP enrollment period of 41.4 months were identified. ED visit rates rose rapidly starting around 19-24 months prior to the opioid OD date. Acute inpatient admission rates and total medical cost also rose rapidly starting around 12 months prior. After the OD date, the utilization rates and cost declined but tended to remain above those of the pre-OD period. CONCLUSION: Opioid OD is preceded by sharp increases in utilization of acute care and cost well before the actual OD. These findings therefore suggest that early signals of OD may be detected from patterns of acute care utilization, particularly the ED visits.

Factors associated with opioid overdose: a 10-year retrospective study of patients in a large integrated health care system.

OBJECTIVE: Opioid overdoses (ODs) have been increasing, and harm reduction efforts are a priority. The success of these efforts will be dependent on the identification of at-risk patients and improved access to the antidote naloxone. Therefore, to identify access to naloxone and factors associated with negative health outcomes, we conducted a retrospective study of patients with OD to identify those at highest risk of adverse outcomes and to assess the use of naloxone. METHODS: We conducted a study of electronic health records for patients admitted to the largest multihospital system in the region - the Geisinger Health System (GHS) for ODs - from April 2005 through March 2015. ODs were defined by International Classification of Diseases-9 codes (age range: 10-95 years). Bivariate analyses and multiple logistic regressions were conducted to identify pre-OD factors associated with adverse health outcomes post-OD. RESULTS: We identified 2,039 patients with one or more ODs, of whom 9.4% were deceased within 12 months. Patient demographics suggest that patients with OD had a mean age of 52 years, were not married (64%), and were unemployed (78%). Common comorbidities among patients with OD include cardiovascular disease (22%), diabetes (14%), cancer (13%), and the presence of one or more mental health disorders (35%). Few patients had a prescription order for naloxone (9%) after their OD. The majority of patients with OD were in proximity to GHS health care facilities, with 87% having a GHS primary care provider. In multiple logistic regressions, common predictors of adverse outcomes, including death, repeated ODs, frequent service use, and high service cost, were higher prescription opioid use, comorbid medical conditions, comorbid mental disorders, and concurrent use of other psychotropic medications. CONCLUSION: This study suggests opportunities for improving OD outcomes. Those who receive higher quantities of prescription opioids concurrent with other psychotropic medicines may need closer monitoring to avoid death, repeated OD events, higher service use, and higher service costs. Other opportunities for improving OD outcomes include the use of electronic health records to notify physicians of high-risk patients and updating of guidelines/operation manuals focused on the distribution of naloxone to those in highest need.

Opioid-use disorder among patients on long-term opioid therapy: impact of final DSM-5 diagnostic criteria on prevalence and correlates.

AIMS: Previously, we estimated the prevalence and risk factors for prescription opioid-use disorder among outpatients on opioid therapy using the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 and DSM-4 criteria. However, at the time, the DSM-5 criteria were not finalized. In the current study, we analyzed these data using the final DSM-5 criteria and compared these results. METHODS: Using electronic records from a large US health care system, we identified outpatients receiving five or more prescription orders for opioid therapy in the past 12 months for noncancer pain (mean prescription orders =10.72; standard deviation =4.96). In 2008, we completed diagnostic interviews with 705 of these patients using the DSM-4 criteria. In the current study, we reassessed these results using the final DSM-5 criteria. RESULTS: The lifetime prevalence of DSM-5 opioid-use disorders using the final DSM-5 criteria was 58.7% for no or few symptoms (<2), 28.1% for mild symptoms (2-3), 9.7% for moderate symptoms (4-5), and 3.5% for severe symptoms (six or more). Thus, the lifetime prevalence of "any" prescription opioid-use disorder in this cohort was 41.3% (95% confidence interval [CI] =37.6-45.0). A comparison to the DSM-4 criteria indicated that the majority of patients with lifetime DSM-4 opioid dependence were now classified as having mild opioid-use disorder, based on the DSM-5 criteria (53.6%; 95% CI =44.1-62.8). In ordinal logistic regression predicting no/few, mild, moderate, and severe opioid-use disorder, the best predictors were age <65 years, current pain impairment, trouble sleeping, suicidal thoughts, anxiety disorders, illicit drug use, and history of substance abuse treatment. CONCLUSION: Given the final DSM-5 criteria, including the elimination of tolerance and withdrawal, inclusion of craving and abuse symptoms, and introduction of a new graded severity classification, the prevalence of opioid-use disorders has changed, while many of the DSM-4 risk factors for opioid dependence were similar. To our knowledge, this is one of the first studies to compare the final results for DSM-5 versus DSM-4 prescription opioid-use disorders among a high-risk patient population.

Prevalence of prescription opioid-use disorder among chronic pain patients: comparison of the DSM-5 vs. DSM-4 diagnostic criteria.

The authors estimated the prevalence of lifetime prescription opioid-use disorder among outpatients on opioid therapy using criteria from both versions 4 and 5 of the Diagnostic and Statistical Manual of Mental Disorders (DSM). Using electronic records from a large health care system, a random sample of outpatients undergoing long-term opioid therapy for non-cancer pain was identified and 705 participants completed diagnostic interviews. The prevalence of lifetime DSM-5 opioid-use disorder among these patients was 34.9% (95% confidence interval [CI] = 30.5?39.5), similar to the prevalence of DSM-4 opioid dependence (35.5%, 95% CI = 31.1?40.2). The Kappa value between DSM-5 and DSM-4 criteria was high (Kappa = 0.873, p < 0.0001). Logistic regressions suggested DSM-5 opioid-use disorder was associated with age younger than 65 (odds ratio [OR] = 2.25, p = 0.009), history of opioid abuse (OR = 4.94, p < 0.001), higher opioid withdrawal symptoms (OR = 3.01, p = 0.008), and history of substance abuse treatment (OR = 1.62, p = 0.015), similar to DSM-4. Based on DSM-5, 21.7% of patients met criteria for moderate and 13.2% for severe opioid-use disorder, respectively. Given the changes proposed, the finding that the prevalence of and risk factors for DSM-5 opioid-use disorders were similar to DSM-4 were unexpected. Further research is advised.

Risk factors for drug dependence among out-patients on opioid therapy in a large US health-care system.

AIMS: Our study sought to assess the prevalence of and risk factors for opioid drug dependence among out-patients on long-term opioid therapy in a large health-care system. METHODS: Using electronic health records, we identified out-patients receiving 4+ physician orders for opioid therapy in the past 12 months for non-cancer pain within a large US health-care system. We completed diagnostic interviews with 705 of these patients to identify opioid use disorders and assess risk factors. RESULTS: Preliminary analyses suggested that current opioid dependence might be as high as 26% [95% confidence interval (CI) = 22.0-29.9] among the patients studied. Logistic regressions indicated that current dependence was associated with variables often in the medical record, including age <65 [odds ratio (OR) = 2.33, P = 0.001], opioid abuse history (OR = 3.81, P < 0.001), high dependence severity (OR = 1.85, P = 0.001), major depression (OR = 1.29, P = 0.022) and psychotropic medication use (OR = 1.73, P = 0.006). Four variables combined (age, depression, psychotropic medications and pain impairment) predicted increased risk for current dependence, compared to those without these factors (OR = 8.01, P < 0.001). Knowing that the patient also had a history of severe dependence and opioid abuse increased this risk substantially (OR = 56.36, P < 0.001). CONCLUSION: Opioid misuse and dependence among prescription opioid patients in the United States may be higher than expected. A small number of factors, many documented in the medical record, predicted opioid dependence among the out-patients studied. These preliminary findings should be useful in future research efforts.