Intentions to Use Cannabis Postpartum: A Qualitative Study of Pregnant Individuals Who Used Cannabis During Early Pregnancy.

Objective: To examine plans for postpartum cannabis use among pregnant individuals who used cannabis during early pregnancy. Materials and Methods: Eighteen virtual focus groups were conducted from November 17, 2021, to December 17, 2021, with 23 Black and 30 White pregnant adults in Kaiser Permanente Northern California, who self-reported prenatal cannabis use during early pregnancy. Focus groups were recorded, transcribed, and analyzed using thematic analysis. Results: The sample (N = 53) had a mean age of 30.3 years (standard deviation = 5.2) at recruitment; 70% reported daily, 25% weekly, and 6% ≤ monthly cannabis use at entrance to prenatal care. Some participants viewed cannabis as critical for coping with postpartum mental and physical health challenges, while others questioned whether cannabis use would fit with their parental lifestyle, and some planned to abstain altogether. Most planned to use cannabis postpartum, but with lower frequency than before pregnancy, and in ways consistent with harm reduction (e.g., smoking outside to avoid secondhand or thirdhand smoke exposure). Many were motivated to abstain from cannabis while breastfeeding, and some desired more data on the safety of cannabis and breastfeeding, or intended to "pump and dump," believing it would reduce potential transfer of Δ9-tetrahydrocannabinol (THC) to their infant. Responses from Black and White participants were generally similar, but White participants were more likely to report plans to use cannabis while breastfeeding and to want information about cannabis and breastfeeding. Conclusions: Pregnant individuals with prenatal cannabis use had varied plans for cannabis use postpartum. Many were motivated to abstain or use cannabis less frequently than pre-pregnancy, especially during lactation.

Agreement Between Self-reports and Urine Toxicology Measures of Illicit Methamphetamine and Cocaine Use During Early Pregnancy.

OBJECTIVE: This study aimed to assess agreement between self-report and urine toxicology measures assessing use of 2 illicit simulants (methamphetamine and cocaine) during early pregnancy. METHODS: This cross-sectional study of 203,053 pregnancies from 169,709 individuals receiving prenatal care at Kaiser Permanente Northern California between January 1, 2011, and December 31, 2019, assessed agreement ( κ , sensitivity, and specificity) between self-reported frequency and urine toxicology measures of methamphetamine and cocaine early in pregnancy. RESULTS: Prenatal use of the illicit stimulants was rare according to toxicology (n = 244 [0.12%]) and self-report measures (n = 294 [0.14%]). Agreement between these measures was low ( κ < 0.20). Of the 498 positive pregnancies, 40 (8.03%) screened positive on both measures, 204 (40.96%) screened positive on toxicology tests only, and 254 (51.00%) screened positive by self-report only. Relative to toxicology tests, sensitivity of any self-reported use was poor with 16.39% (95% confidence interval [CI], 11.75%-21.04%) of pregnancies with a positive toxicology test self-reporting any use in pregnancy. Relative to self-report, sensitivity of toxicology tests was also poor with 13.61% (95% CI, 9.69%-17.52%) of pregnancies who self-reported any use having positive urine toxicology tests. The sensitivity improved slightly at higher frequencies of self-reported use: daily, 17.50% (95% CI, 5.72%-29.29%); weekly, 25.00% (95% CI, 11.58%-38.42%); and monthly or less, 11.06% (95% CI, 6.89%-15.23%). Specificity was high (>99%), reflecting the high negative rate of use. CONCLUSIONS: Findings suggest that using self-report and toxicology measures in combination likely provides the most accurate information on methamphetamine and cocaine use in early pregnancy. Findings also highlight the need to provide supportive nonstigmatizing environments in which pregnant individuals feel comfortable disclosing substance use without fear of punishment.

Patient Perceptions of Prenatal Cannabis Use and Implications for Clinicians.

OBJECTIVE: To understand pregnant patients' reasons for prenatal cannabis use and perceptions of safety, desired and undesirable health care experiences, and desired information about prenatal cannabis use and secondarily to understand racial differences in these perceptions and preferences. METHODS: We conducted a qualitative study including 18 semi-structured, race-concordant virtual focus groups with pregnant individuals who self-reported cannabis use at prenatal care entry in a large integrated health care system in Northern California from November 2021 to December 2021. The focus groups included semi-structured questions that were recorded, transcribed, and coded by the research team. Thematic analysis was used to analyze the data. RESULTS: Overall, 53 participants were included; 30 self-identified, as White and 23 self-identified as Black. Participants averaged 30.3 years of age (SD 5.2 years) and were on average at 20.9 weeks of gestation at study enrollment; 69.8% reported daily cannabis use, 24.5% reported weekly cannabis use, and 5.7% reported monthly or less cannabis use at entrance to prenatal care. Although some participants quit cannabis use in early pregnancy because of concerns about potential health risks, many perceived a lack of scientific evidence or believed that prenatal cannabis use was safe. Many preferred cannabis to over-the-counter or prescription medications for treating mood, morning sickness, pain, and sleep. Participants valued open interactions with obstetricians that acknowledged their motivations for use, and they desired information about potential risks through conversations and educational materials. White and Black participants' perspectives were generally similar, but a few Black participants uniquely described concerns about racial bias related to their prenatal cannabis use. CONCLUSION: Pregnant patients used cannabis to manage mood and medical symptoms, and many believed that prenatal cannabis use was safer than the use of prescription medications. Obstetrician-initiated, patient-centered conversations around prenatal cannabis use, advice to discontinue cannabis use during pregnancy, and exploration of willingness to switch to medically recommended interventions for pregnancy-related symptoms may benefit patients.

Patterns of Substance Use During Early Pregnancy and Associations With Behavioral Health Characteristics.

OBJECTIVES: The aims of the study are to identify patterns of early pregnancy substance use and to examine how these patterns relate to behavioral health conditions measured in early pregnancy. METHODS: We conducted a retrospective observational study (N= 265,274 pregnancies) screened for alcohol, cannabis, nicotine, pharmaceutical opioids, and stimulants during the first trimester via self-report and urine toxicology tests in Kaiser Permanente Northern California from January 1, 2012, to December 31, 2019. To identify patterns of prenatal substance use, we conducted latent class analysis. We then calculated the prevalence of depression, anxiety, intimate partner violence, and family drug use history for each prenatal substance use group and compared the prevalences by estimating prevalence ratios using modified Poisson regression, adjusting for sociodemographic characteristics. RESULTS: We identified the following 4 latent groups with different patterns of substance use: ( a ) predominantly alcohol and no other substances (9.30%), ( b ) predominantly cannabis and no other substances (4.88%), ( c ) predominantly nicotine and some pharmaceutical opioids (1.09%), and ( d ) high-polysubstance (alcohol, cannabis, nicotine, and stimulants; 0.36%); these pregnancies were compared with ( e ) no prenatal substance use (84.37%). The prevalence of all behavioral health conditions was elevated in all prenatal substance use groups compared with the no substance use group. Furthermore, the prevalence of depressive and anxiety disorders, intimate partner violence and family drug use history were greater in the high-polysubstance cluster than the alcohol and cannabis clusters. CONCLUSIONS: Results highlight the importance of screening and interventions for all types of substance use during early pregnancy and suggest a particularly high need to prioritize targeting early interventions to pregnant and reproductive age individuals with polysubstance use.

Pregnant individual's lived experience of cannabis use during the COVID-19 pandemic: a qualitative study.

Introduction: Quantitative studies indicate that the COVID-19 pandemic has contributed to increased rates of prenatal cannabis use. However, little is known about how the pandemic has impacted cannabis use from the perspective of pregnant individuals themselves. Our objective was to characterize COVID-19-related changes in cannabis use among pregnant individuals who used cannabis during the pandemic. Methods: We conducted 18 focus groups (from 11/17/2021 to 12/17/2021) with Black and White pregnant individuals aged 18+ who self-reported prenatal cannabis use during universal screening at entrance to prenatal care (at ~8 weeks gestation) in Kaiser Permanente Northern California. Virtual focus groups were transcribed and analyzed using thematic analysis. Results: The sample of 53 pregnant individuals (23 Black, 30 White) was 30.3 years old (SD = 5.2) on average, and most (70%) self-reported daily versus weekly or monthly prenatal cannabis use. Major themes regarding the impact of the pandemic on cannabis use included increases in use (resulting from depression, anxiety, stress, boredom), and changes in social use (less sharing of smoked cannabis products), modes of use (from smoking to other modes due to respiratory concerns) and source (from storefront retailers to delivery). Conclusion: Coping with mental health symptoms and stress were identified drivers of perceived pandemic-related increases in prenatal cannabis use in 2021. Pregnant individuals adapted their use in ways consistent with public health recommendations to decrease social contact and reduce or quit smoking to mitigate COVID-19 transmission and harms. Proactive, mental health outreach for pregnant individuals during future pandemic waves may reduce prenatal cannabis use.

The ETS transcription factor ETV6 constrains the transcriptional activity of EWS-FLI to promote Ewing sarcoma.

Transcription factors (TFs) are frequently mutated in cancer. Paediatric cancers exhibit few mutations genome-wide but frequently harbour sentinel mutations that affect TFs, which provides a context to precisely study the transcriptional circuits that support mutant TF-driven oncogenesis. A broadly relevant mechanism that has garnered intense focus involves the ability of mutant TFs to hijack wild-type lineage-specific TFs in self-reinforcing transcriptional circuits. However, it is not known whether this specific type of circuitry is equally crucial in all mutant TF-driven cancers. Here we describe an alternative yet central transcriptional mechanism that promotes Ewing sarcoma, wherein constraint, rather than reinforcement, of the activity of the fusion TF EWS-FLI supports cancer growth. We discover that ETV6 is a crucial TF dependency that is specific to this disease because it, counter-intuitively, represses the transcriptional output of EWS-FLI. This work discovers a previously undescribed transcriptional mechanism that promotes cancer.

Transcriptional Antagonism by CDK8 Inhibition Improves Therapeutic Efficacy of MEK Inhibitors.

Aberrant RAS/MAPK signaling is a common driver of oncogenesis that can be therapeutically targeted with clinically approved MEK inhibitors. Disease progression on single-agent MEK inhibitors is common, however, and combination therapies are typically required to achieve significant clinical benefit in advanced cancers. Here we focused on identifying MEK inhibitor-based combination therapies in neuroblastoma with mutations that activate the RAS/MAPK signaling pathway, which are rare at diagnosis but frequent in relapsed neuroblastoma. A genome-scale CRISPR-Cas9 functional genomic screen was deployed to identify genes that when knocked out sensitize RAS-mutant neuroblastoma to MEK inhibition. Loss of either CCNC or CDK8, two members of the mediator kinase module, sensitized neuroblastoma to MEK inhibition. Furthermore, small-molecule kinase inhibitors of CDK8 improved response to MEK inhibitors in vitro and in vivo in RAS-mutant neuroblastoma and other adult solid tumors. Transcriptional profiling revealed that loss of CDK8 or CCNC antagonized the transcriptional signature induced by MEK inhibition. When combined, loss of CDK8 or CCNC prevented the compensatory upregulation of progrowth gene expression induced by MEK inhibition. These findings propose a new therapeutic combination for RAS-mutant neuroblastoma and may have clinical relevance for other RAS-driven malignancies. SIGNIFICANCE: Transcriptional adaptation to MEK inhibition is mediated by CDK8 and can be blocked by the addition of CDK8 inhibitors to improve response to MEK inhibitors in RAS-mutant neuroblastoma, a clinically challenging disease.

Association of cannabis use during pregnancy with severe acute respiratory syndrome coronavirus 2 infection: a retrospective cohort study.

BACKGROUND AND AIMS: Cannabis use is increasingly common among pregnant individuals and might be a risk factor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to test whether prenatal cannabis use is associated with increased risk of SARS-CoV-2 infection during pregnancy. DESIGN: This is a retrospective cohort study. SETTING: The study was conducted in California, USA. PARTICIPANTS: A total of 58 114 pregnancies (with outcomes from 5 March 2020 to 30 September 2021) among 57 287 unique pregnant women aged 14-54 years who were screened for prenatal substance use, enrolled in Kaiser Permanente Northern California (KPNC) (a health-care system) and had not tested positive for COVID-19 prior to pregnancy onset. MEASUREMENTS: We utilized data from the KPNC electronic health record. Cannabis use status (current, recently quit and non-user) was based on universal screenings during prenatal care (including urine toxicology testing and self-reported use on a self-administered questionnaire). SARS-CoV-2 infection [based on polymerase chain reaction (PCR) tests] was estimated in time-to-event analyses using Cox proportional hazard regression models adjusting for covariates. Secondary analyses examined differences in (a) SARS-CoV-2 testing rates and (b) SARS-CoV-2 infection rates among those tested. FINDINGS: We observed 348 810 person-months of follow-up time in our cohort with 41 064 SARS-CoV-2 PCR tests and 6% (n = 2414) of tests being positive. At the start of follow-up, 7% of pregnant individuals had current use, 12% had recently quit and 81% did not use cannabis. Adjusting for covariates, current use was associated with lower rates of SARS-CoV-2 infection [adjusted hazard ratio (aHR) = 0.60, 95% confidence interval (CI) = 0.49-0.74 than non-use. Those who had recently quit did not differ from non-cannabis users in infection rates (aHR = 0.96, 95% CI = 0.86-1.08). Sensitivity analyses among patients who received a SARS-CoV-2 test also found lower odds of infection associated with current versus no cannabis use (aOR = 0.76, CI = 0.61-0.93). CONCLUSIONS: Current cannabis use appears to be associated with a reduced risk of SARS-CoV-2 infection among pregnant individuals.

Perceptions About Cannabis Following Legalization Among Pregnant Individuals With Prenatal Cannabis Use in California.

Importance: As rates of prenatal cannabis use increase and cannabis legalization spreads across the US, studies are needed to understand the potential impacts of legalization from the perspectives of pregnant individuals who use cannabis. Objective: To characterize pregnant individuals' perspectives on legalization of cannabis for adult use in California (effective in 2018) in relation to prenatal cannabis use behaviors and beliefs. Design, Setting, and Participants: This qualitative study was conducted in Kaiser Permanente Northern California, a large health care system with universal screening for self-reported cannabis use at entrance to prenatal care. Eighteen semistructured focus groups were conducted from November 17 to December 17, 2021, using a secure video conferencing platform with Black and White pregnant participants who self-reported cannabis use during early pregnancy. Data were analyzed from March to June 2022. Main Outcomes and Measures: Video-recorded interviews were transcribed and analyzed using thematic analysis to identify major themes and subthemes. Results: Among 53 participants (mean [SD] age, 30.3 [5.2] years), 23 (43%) identified as non-Hispanic Black and 30 (57%) identified as non-Hispanic White; 16 participants (30%) reported continued cannabis use at the time of recruitment. Major themes regarding the perceived impact of legalization included easier access (via retailers and delivery), greater acceptance (including reduced stigma and more discussions about prenatal cannabis use with health care practitioners), and trust in cannabis retailers (including safety and effectiveness of diverse products sold and perceptions of cannabis retailer employees as knowledgeable, nonjudgmental, and caring). Responses were mixed about whether retailer marketing and advertising were associated with prenatal cannabis use and whether legalization resulted in reduced concerns about Child Protective Services involvement. Conclusion and Relevance: The findings of this qualitative study suggest pregnant individuals perceive cannabis legalization as having reduced barriers to prenatal cannabis use and that legalization has created challenges and opportunities for supporting the health of pregnant individuals. The results of this qualitative study highlight key areas that can be further explored in future educational materials, public health campaigns, and policy adaptations to address increasing rates of prenatal cannabis use.

Geographic Accessibility of Retail Cannabis in Northern California and Prenatal Cannabis Use During the COVID-19 Pandemic.

Importance: Prenatal cannabis use is associated with health risks for mothers and their children. Prior research suggests that rates of prenatal cannabis use in Northern California increased during the COVID-19 pandemic, but it is unknown whether increases varied with the local cannabis retail and policy environment. Objective: To test whether pandemic-related increases in prenatal cannabis use were greater among pregnant individuals with greater retail availability of cannabis around their homes or among those living in jurisdictions that allowed storefront retailers. Design, Setting, and Participants: A cross-sectional, population-based time series study used data from pregnancies in the Kaiser Permanente Northern California health care system screened for cannabis use before (January 1, 2019, to March 31, 2020) and during (April 1 to December 31, 2020) the early COVID-19 pandemic. Proximity to the nearest retailer and number of retailers within a 15-minute drive from one's home and local cannabis storefront retailer policy (banned vs permitted) were calculated. Interrupted time series models were fit using multiplicative and additive Poisson regression, adjusting for age and race and ethnicity. Exposures: The COVID-19 pandemic. Main Outcomes and Measures: Prenatal cannabis use based on universal urine toxicology tests conducted during early pregnancy at entrance to prenatal care. Results: The sample (n = 99 127 pregnancies) included 26.2% Asian or Pacific Islander, 6.8% Black, 27.6% Hispanic, 34.4% non-Hispanic White, and 4.9% other, unknown, or multiracial individuals, with a mean (SD) age of 30.8 (5.3) years. Prenatal cannabis use before (6.8%) and during (8.2%) the pandemic was associated with closer proximity to a retailer, greater retailer density, and residing in a jurisdiction that permitted vs banned retailers. There was a greater absolute increase in cannabis use from before to during the pandemic among those within a 10-minute drive (<10 minutes: adjusted rate difference [aRD], 0.93 cases/100 patients; 95% CI, 0.56-1.29 cases/100 patients; ≥10 minutes: aRD, 0.40 cases/100 patients; 95% CI, 0.12-0.68 cases/100 patients; interaction P = .02). Otherwise, relative and absolute rates increased similarly across categories of cannabis retailer proximity/density and local policy (interaction P > .05). Conclusions and Relevance: Prenatal cannabis use was more common among individuals living in areas with greater retail availability of cannabis. Although relative rates increased similarly during the pandemic regardless of local cannabis retail and policy environment, there was a larger absolute increase associated with living closer to a storefront cannabis retailer. Continued monitoring of local cannabis policy, the retail environment, and prenatal cannabis use is needed.

BAF Complex Maintains Glioma Stem Cells in Pediatric H3K27M Glioma.

Diffuse midline gliomas are uniformly fatal pediatric central nervous system cancers that are refractory to standard-of-care therapeutic modalities. The primary genetic drivers are a set of recurrent amino acid substitutions in genes encoding histone H3 (H3K27M), which are currently undruggable. These H3K27M oncohistones perturb normal chromatin architecture, resulting in an aberrant epigenetic landscape. To interrogate for epigenetic dependencies, we performed a CRISPR screen and show that patient-derived H3K27M-glioma neurospheres are dependent on core components of the mammalian BAF (SWI/SNF) chromatin remodeling complex. The BAF complex maintains glioma stem cells in a cycling, oligodendrocyte precursor cell-like state, in which genetic perturbation of the BAF catalytic subunit SMARCA4 (BRG1), as well as pharmacologic suppression, opposes proliferation, promotes progression of differentiation along the astrocytic lineage, and improves overall survival of patient-derived xenograft models. In summary, we demonstrate that therapeutic inhibition of the BAF complex has translational potential for children with H3K27M gliomas. SIGNIFICANCE: Epigenetic dysregulation is at the core of H3K27M-glioma tumorigenesis. Here, we identify the BRG1-BAF complex as a critical regulator of enhancer and transcription factor landscapes, which maintain H3K27M glioma in their progenitor state, precluding glial differentiation, and establish pharmacologic targeting of the BAF complex as a novel treatment strategy for pediatric H3K27M glioma. See related commentary by Beytagh and Weiss, p. 2730. See related article by Mo et al., p. 2906.

Transition to a mesenchymal state in neuroblastoma confers resistance to anti-GD2 antibody via reduced expression of ST8SIA1.

Immunotherapy with anti-GD2 antibodies has advanced the treatment of children with high-risk neuroblastoma, but nearly half of patients relapse, and little is known about mechanisms of resistance to anti-GD2 therapy. Here, we show that reduced GD2 expression was significantly correlated with the mesenchymal cell state in neuroblastoma and that a forced adrenergic-to-mesenchymal transition (AMT) conferred downregulation of GD2 and resistance to anti-GD2 antibody. Mechanistically, low-GD2-expressing cell lines demonstrated significantly reduced expression of the ganglioside synthesis enzyme ST8SIA1 (GD3 synthase), resulting in a bottlenecking of GD2 synthesis. Pharmacologic inhibition of EZH2 resulted in epigenetic rewiring of mesenchymal neuroblastoma cells and re-expression of ST8SIA1, restoring surface expression of GD2 and sensitivity to anti-GD2 antibody. These data identify developmental lineage as a key determinant of sensitivity to anti-GD2 based immunotherapies and credential EZH2 inhibitors for clinical testing in combination with anti-GD2 antibody to enhance outcomes for children with neuroblastoma.

Trends in Cannabis Polysubstance Use During Early Pregnancy Among Patients in a Large Health Care System in Northern California.

Importance: Rates of prenatal cannabis use are increasing alongside perceptions that cannabis is a harmless therapeutic for pregnancy-related ailments, while rates of prenatal use of alcohol and tobacco are decreasing. It is important to examine whether cannabis use during pregnancy is increasing similarly among patients with and patients without co-occurring substance use. Objectives: To examine trends in cannabis polysubstance use during pregnancy and to test differences in cannabis use over time among pregnant individuals who use only cannabis vs those who use cannabis and other substances. Design, Setting, and Participants: This cross-sectional time-series study used data from 367 138 pregnancies among 281 590 unique pregnant patients universally screened for prenatal substance use as part of standard care in Kaiser Permanente Northern California from January 1, 2009, to December 31, 2018. Statistical analysis was performed from October 5, 2021, to April 18, 2022. Exposures: Time (calendar year). Main Outcomes and Measures: Use of substances during early pregnancy was assessed via universal screening with a self-administered questionnaire (for cannabis, alcohol, stimulants, and nicotine) and/or positive results of a urine toxicology test (for cannabis, alcohol, stimulants, and pharmaceutical opioids), and data were extracted from the electronic health record. Results: The study sample of 367 138 pregnancies from 281 590 unique pregnant patients (median gestation at time of screening, 8.6 weeks [IQR, 7.3-10.6 weeks]) was 25.9% Asian or Pacific Islander, 6.6% Black, 25.8% Hispanic, 38.0% non-Hispanic White, and 3.6% other race or ethnicity; 1.1% were aged 11 to 17 years, 14.9% were aged 18 to 24 years, 61.9% were aged 25 to 34 years, and 22.1% were aged 35 years or older; and the median neighborhood household income was $70 455 (IQR, $51 563-$92 625). From 2009 to 2018, adjusted rates of use of only cannabis during pregnancy (no other substances) increased substantially from 2.39% (95% CI, 2.20%-2.58%) in 2009 to 6.30% (95% CI, 6.00%-6.60%) in 2018, increasing at an annual relative rate of 1.11 (95% CI, 1.10-1.12). The rate of use of cannabis and 1 other substance also increased (annual relative rate, 1.04 [95% CI, 1.03-1.05]), but not as rapidly (P < .001 for difference), while the rate of use of cannabis and 2 or more other substances decreased slightly (annual relative rate, 0.97 [95% CI, 0.96-0.99]). Adjusted rates of prenatal use of cannabis and alcohol (1.04 [95% CI, 1.03-1.06]) and cannabis and stimulants (1.03 [95% CI, 1.01-1.06]) increased over time, while rates of prenatal use of cannabis and nicotine (0.97 [95% CI, 0.96-0.98]) decreased. Conclusions and Relevance: In this cross-sectional time-series study, rates of prenatal cannabis use during early pregnancy increased significantly more rapidly among patients without co-occurring substance use, which could reflect increased acceptability of cannabis and decreased perceptions of cannabis-related harms. Furthermore, increased rates of use of cannabis with alcohol and stimulants warrant continued monitoring.

Unleashing Cell-Intrinsic Inflammation as a Strategy to Kill AML Blasts.

Leukemic blasts are immune cells gone awry. We hypothesized that dysregulation of inflammatory pathways contributes to the maintenance of their leukemic state and can be exploited as cell-intrinsic, self-directed immunotherapy. To this end, we applied genome-wide screens to discover genetic vulnerabilities in acute myeloid leukemia (AML) cells implicated in inflammatory pathways. We identified the immune modulator IRF2BP2 as a selective AML dependency. We validated AML cell dependency on IRF2BP2 with genetic and protein degradation approaches in vitro and genetically in vivo. Chromatin and global gene-expression studies demonstrated that IRF2BP2 represses IL1ß/TNFα signaling via NFκB, and IRF2BP2 perturbation results in an acute inflammatory state leading to AML cell death. These findings elucidate a hitherto unexplored AML dependency, reveal cell-intrinsic inflammatory signaling as a mechanism priming leukemic blasts for regulated cell death, and establish IRF2BP2-mediated transcriptional repression as a mechanism for blast survival. SIGNIFICANCE: This study exploits inflammatory programs inherent to AML blasts to identify genetic vulnerabilities in this disease. In doing so, we determined that AML cells are dependent on the transcriptional repressive activity of IRF2BP2 for their survival, revealing cell-intrinsic inflammation as a mechanism priming leukemic blasts for regulated cell death. See related commentary by Puissant and Medyouf, p. 1617. This article is highlighted in the In This Issue feature, p. 1599.

Modes of cannabis administration in the year prior to conception among patients in Northern California.

Cannabis use among individuals before and during pregnancy is increasing alongside the proliferation of new products with various modes of administration. Preconception cannabis use is a strong predictor of prenatal cannabis use. Yet little is known about how individuals administer cannabis during the preconception period, particularly in socioeconomically vulnerable populations. This study examined the prevalence and correlates of modes of cannabis administration (smoke, vape, blunts, edible/oral, dabs/wax, lotion/topical) during the year before conception, among patients who self-reported preconception cannabis use during universal screening in prenatal care. Descriptive statistics included sociodemographic characteristics, preconception cannabis use frequency, and modes of administration. Chi-square tests examined whether mode was associated with sociodemographic characteristics and use frequency. The sample (N = 11,936, screened from February 2020-May 2021) was 59.8% non-White and 26.1% were < 26 years old; 50.7% reported monthly or less, 21.8% weekly, and 27.4% daily preconception cannabis use; 69.7% smoked (any method), 34.5% smoked blunts, 53.4% used edibles/oral, 28.2% vaped, 9.9% used lotion/topical; 54.2% reported 1 mode, 30.4% reported 2 modes, 15.4% reported 3+ modes. Smoking was more common among daily users, younger patients, those with greater neighborhood deprivation, and Black and Hispanic patients, while edibles/oral were more common among ≤ monthly users, older patients, those with less neighborhood deprivation, and Asian patients. Use of other modes also varied by sociodemographic characteristics and use frequency. Research is needed to understand preconception cannabis use in vulnerable subpopulations, continuation of use during pregnancy, and whether health risks associated with preconception and prenatal cannabis use differ by administration mode.

An In Vivo CRISPR Screening Platform for Prioritizing Therapeutic Targets in AML.

CRISPR-Cas9-based genetic screens have successfully identified cell type-dependent liabilities in cancer, including acute myeloid leukemia (AML), a devastating hematologic malignancy with poor overall survival. Because most of these screens have been performed in vitro using established cell lines, evaluating the physiologic relevance of these targets is critical. We have established a CRISPR screening approach using orthotopic xenograft models to validate and prioritize AML-enriched dependencies in vivo, including in CRISPR-competent AML patient-derived xenograft (PDX) models tractable for genome editing. Our integrated pipeline has revealed several targets with translational value, including SLC5A3 as a metabolic vulnerability for AML addicted to exogenous myo-inositol and MARCH5 as a critical guardian to prevent apoptosis in AML. MARCH5 repression enhanced the efficacy of BCL2 inhibitors such as venetoclax, further highlighting the clinical potential of targeting MARCH5 in AML. Our study provides a valuable strategy for discovery and prioritization of new candidate AML therapeutic targets. SIGNIFICANCE: There is an unmet need to improve the clinical outcome of AML. We developed an integrated in vivo screening approach to prioritize and validate AML dependencies with high translational potential. We identified SLC5A3 as a metabolic vulnerability and MARCH5 as a critical apoptosis regulator in AML, both of which represent novel therapeutic opportunities.This article is highlighted in the In This Issue feature, p. 275.

Targeting serine hydroxymethyltransferases 1 and 2 for T-cell acute lymphoblastic leukemia therapy.

Despite progress in the treatment of acute lymphoblastic leukemia (ALL), T-cell ALL (T-ALL) has limited treatment options, particularly in the setting of relapsed/refractory disease. Using an unbiased genome-scale CRISPR-Cas9 screen we sought to identify pathway dependencies for T-ALL which could be harnessed for therapy development. Disruption of the one-carbon folate, purine and pyrimidine pathways scored as the top metabolic pathways required for T-ALL proliferation. We used a recently developed inhibitor of SHMT1 and SHMT2, RZ-2994, to characterize the effect of inhibiting these enzymes of the one-carbon folate pathway in T-ALL and found that T-ALL cell lines were differentially sensitive to RZ-2994, with the drug inducing a S/G2 cell cycle arrest. The effects of SHMT1/2 inhibition were rescued by formate supplementation. Loss of both SHMT1 and SHMT2 was necessary for impaired growth and cell cycle arrest, with suppression of both SHMT1 and SHMT2 inhibiting leukemia progression in vivo. RZ-2994 also decreased leukemia burden in vivo and remained effective in the setting of methotrexate resistance in vitro. This study highlights the significance of the one-carbon folate pathway in T-ALL and supports further development of SHMT inhibitors for treatment of T-ALL and other cancers.

EP300 Selectively Controls the Enhancer Landscape of MYCN-Amplified Neuroblastoma.

Gene expression is regulated by promoters and enhancers marked by histone H3 lysine 27 acetylation (H3K27ac), which is established by the paralogous histone acetyltransferases (HAT) EP300 and CBP. These enzymes display overlapping regulatory roles in untransformed cells, but less characterized roles in cancer cells. We demonstrate that the majority of high-risk pediatric neuroblastoma (NB) depends on EP300, whereas CBP has a limited role. EP300 controls enhancer acetylation by interacting with TFAP2ß, a transcription factor member of the lineage-defining transcriptional core regulatory circuitry (CRC) in NB. To disrupt EP300, we developed a proteolysis-targeting chimera (PROTAC) compound termed "JQAD1" that selectively targets EP300 for degradation. JQAD1 treatment causes loss of H3K27ac at CRC enhancers and rapid NB apoptosis, with limited toxicity to untransformed cells where CBP may compensate. Furthermore, JQAD1 activity is critically determined by cereblon (CRBN) expression across NB cells. SIGNIFICANCE: EP300, but not CBP, controls oncogenic CRC-driven transcription in high-risk NB by binding TFAP2ß. We developed JQAD1, a CRBN-dependent PROTAC degrader with preferential activity against EP300 and demonstrated its activity in NB. JQAD1 has limited toxicity to untransformed cells and is effective in vivo in a CRBN-dependent manner. This article is highlighted in the In This Issue feature, p. 587.

Association of Pregnancy Intentions With Substance Use During Early Pregnancy.

OBJECTIVES: The goal of this study was to evaluate the association between pregnancy intentions and substance use in early pregnancy among pregnant women receiving prenatal care in a large, integrated healthcare system. METHODS: The sample comprised 29,787 Kaiser Permanente Northern California pregnant women (12.1% aged <25, 36.4% non-Hispanic White) screened for prenatal substance use in 2018 via a self-reported questionnaire and urine toxicology test given as part of standard prenatal care (at ∼8 weeks gestation). Multivariable logistic regression models tested for associations of pregnancy intentions with prenatal substance use (any use and specific substances) by self-report and/or a positive urine toxicology test. RESULTS: Adjusting for covariates, women with an unintended pregnancy (23.9% of the sample) had higher odds of any prenatal substance use than women with an intended pregnancy (28.8% vs 16.1%; adjusted odds ratio [aOR] = 1.80, 95% confidence interval [CI]:1.67-1.93). Having an unintended pregnancy was also associated with higher odds of using alcohol (14.4% vs 10.4%; aOR = 1.73, 95%CI:1.59-1.89), cannabis (15.6% vs 5.6%; aOR = 1.91, 95%CI:1.73-2.11), nicotine (3.8% vs 1.3%; aOR = 2.33, 95%CI:1.92-2.82), pain medication (2.3% vs 1.2%; aOR = 1.64, 95%CI:1.32-2.03), and stimulants (0.8% vs 0.3%; aOR = 1.85, 95%CI:1.23-2.79) early in pregnancy. DISCUSSION: Having an unintended pregnancy was associated with higher odds of substance use during early pregnancy. Connecting women of reproductive age with health education about pregnancy prevention and recognition of early signs of pregnancy, effective contraception, and early screening and interventions for prenatal substance use may help to reduce prenatal substance use and its associated consequences.