GAP43-dependent mitochondria transfer from astrocytes enhances glioblastoma tumorigenicity.

The transfer of intact mitochondria between heterogeneous cell types has been confirmed in various settings, including cancer. However, the functional implications of mitochondria transfer on tumor biology are poorly understood. Here we show that mitochondria transfer is a prevalent phenomenon in glioblastoma (GBM), the most frequent and malignant primary brain tumor. We identified horizontal mitochondria transfer from astrocytes as a mechanism that enhances tumorigenesis in GBM. This transfer is dependent on network-forming intercellular connections between GBM cells and astrocytes, which are facilitated by growth-associated protein 43 (GAP43), a protein involved in neuron axon regeneration and astrocyte reactivity. The acquisition of astrocyte mitochondria drives an increase in mitochondrial respiration and upregulation of metabolic pathways linked to proliferation and tumorigenicity. Functionally, uptake of astrocyte mitochondria promotes cell cycle progression to proliferative G2/M phases and enhances self-renewal and tumorigenicity of GBM. Collectively, our findings reveal a host-tumor interaction that drives proliferation and self-renewal of cancer cells, providing opportunities for therapeutic development.

Factors Associated With Chlamydia and Gonorrhea Treatment Completion Among Sexual Health Clinic Patients, Baltimore City, Maryland; 2018 to 2019.

BACKGROUND: Prompt and appropriate treatment of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) is critical to prevent transmission and serious sequelae. The objectives were to determine the prevalence of CT/NG treatment completion and identify demographic, behavioral, and clinical factors associated with treatment completion at sexual health clinics in Baltimore City, Maryland. METHODS: Electronic health record data from patients diagnosed with CT/NG during 2018-2019 were analyzed. Treatment completion was defined as documentation of Centers for Disease Control and Prevention-recommended treatment ≤30 days after testing. Regression was used to assess differences in treatment completion across groups; analyses were stratified by birth sex. RESULTS: Most of the 2426 male (86%) and 754 (72%) female patients diagnosed with CT/NG completed treatment in ≤30 days; 74% of male and 36% of female patients were treated same-day. Among 890 male patients not treated same-day, treatment completion was associated with other same-day antimicrobial treatments (adjusted prevalence ratio, 0.76 [95% confidence interval, 0.61-0.94]), longer test processing times (≥10 days; 0.78 [0.65-0.95]) infection at multiple anatomic sites (1.49 [1.25-1.76]), and patients with previous clinic visits (1.16 [1.03-1.31]). Among 483 female patients not treated same-day, treatment completion was associated with diagnosis year (2019 vs. 2018; 1.23 [1.05-1.43]) and residential addresses 2 to 5 miles (vs. <2 miles) from clinic (1.25 [1.02-1.53]). Demographic and behavioral characteristics were not associated with treatment completion. CONCLUSIONS: Substantial proportions of male and female sexual health clinic patients did not complete treatment. Our findings underscore the need for implementation of highly sensitive and specific point-of-care (POC) CT/NG testing to improve treatment completion in this setting.

Characteristics of Reported Gonorrhea Diagnoses During The COVID-19 Pandemic Compared With Pre-COVID-19 Pandemic, Baltimore City, Maryland.

BACKGROUND: Sexual health service disruptions due to COVID-19 mitigation measures may have decreased gonorrhea screening and biased case-ascertainment toward symptomatic individuals. We assessed changes in reported symptoms and other characteristics among reported gonorrhea cases during pandemic versus prepandemic periods in 1 city with persistent gonorrhea transmission. METHODS: Enhanced surveillance data collected on a random sample of gonorrhea cases reported to the Baltimore City Health Department between March 2018 and September 2021 was used. Logistic regression assessed differences in case characteristics by diagnosis period (during pandemic: March 2020-September 2021; prepandemic: March 2018-September 2019). RESULTS: Analyses included 2750 (1090 during pandemic, 1660 prepandemic) gonorrhea cases, representing 11,904 reported cases. During pandemic versus prepandemic, proportionally fewer cases were reported by sexual health clinics (8.8% vs 23.2%), and more frequently reported by emergency departments/urgent care centers (23.3% vs 11.9%). Adjusting for diagnosing provider, fewer cases who were men with urethral infections (adjusted odds ratio [aOR], 0.65; 95% confidence interval [CI], 0.55-0.77), aged <18 years (aOR, 0.64; 95% CI, 0.47-0.89), and women (aOR, 0.84; 95% CI, 0.71-0.99) were reported, and cases with insurance (aOR, 1.85; 95% CI, 1.40-2.45), living with human immunodeficiency virus (aOR, 1.43; 95% CI, 1.12-1.83), or recent (≤12 months) gonorrhea history (aOR, 1.25; 95% CI, 1.02-1.53) were more frequently reported during pandemic versus prepandemic. Reported symptoms and same-day/empiric treatment did not differ across periods. CONCLUSIONS: We observed no changes in reported symptoms among cases diagnosed during pandemic versus prepandemic. Increased frequency of reported diagnoses who were insured, living with human immunodeficiency virus, or with recent gonorrhea history are suggestive of differences in care access and care-seeking behaviors among populations with high gonorrhea transmission during the pandemic.

Targeting Acid Ceramidase Inhibits Glioblastoma Cell Migration through Decreased AKT Signaling.

Glioblastoma (GBM) remains one of the most aggressive cancers, partially due to its ability to migrate into the surrounding brain. The sphingolipid balance, or the balance between ceramides and sphingosine-1-phosphate, contributes to the ability of GBM cells to migrate or invade. Of the ceramidases which hydrolyze ceramides, acid ceramidase (ASAH1) is highly expressed in GBM samples compared to non-tumor brain. ASAH1 expression also correlates with genes associated with migration and focal adhesion. To understand the role of ASAH1 in GBM migration, we utilized shRNA knockdown and observed decreased migration that did not depend upon changes in growth. Next, we inhibited ASAH1 using carmofur, a clinically utilized small molecule inhibitor. Inhibition of ASAH1 by carmofur blocks in vitro migration of U251 (GBM cell line) and GBM cells derived from patient-derived xenografts (PDXs). RNA-sequencing suggested roles for carmofur in MAPK and AKT signaling. We found that carmofur treatment decreases phosphorylation of AKT, but not of MAPK. The decrease in AKT phosphorylation was confirmed by shRNA knockdown of ASAH1. Our findings substantiate ASAH1 inhibition using carmofur as a potential clinically relevant treatment to advance GBM therapeutics, particularly due to its impact on migration.

Rapid Uptake of Testing for Chlamydia, Gonorrhea, and HIV From an Online Platform, April-October 2020.

The Baltimore City Health Department (Baltimore, MD) promoted IWantTheKit for chlamydia, gonorrhea, and HIV testing to city residents and clinic patients when COVID-19 restricted in-person clinic services. From April to October 2020, monthly online IWantTheKit orders increased by 645%. A high prevalence of chlamydia and gonorrhea was detected, and 96% of users who tested positive for chlamydia and gonorrhea were successfully contacted for treatment. Uptake by Baltimore City Health Department priority populations and excellent treatment linkage demonstrated how a public health-academic partnership successfully addressed a service gap during the pandemic. (Am J Public Health. 2022;112(7):985-989. https://doi.org/10.2105/AJPH.2022.306835).

Novel dopamine receptor 3 antagonists inhibit the growth of primary and temozolomide resistant glioblastoma cells.

Treatment for the lethal primary adult brain tumor glioblastoma (GBM) includes the chemotherapy temozolomide (TMZ), but TMZ resistance is common and correlates with promoter methylation of the DNA repair enzyme O-6-methylguanine-DNA methyltransferase (MGMT). To improve treatment of GBMs, including those resistant to TMZ, we explored the potential of targeting dopamine receptor signaling. We found that dopamine receptor 3 (DRD3) is expressed in GBM and is also a previously unexplored target for therapy. We identified novel antagonists of DRD3 that decreased the growth of GBM xenograft-derived neurosphere cultures with minimal toxicity against human astrocytes and/or induced pluripotent stem cell-derived neurons. Among a set of DRD3 antagonists, we identified two compounds, SRI-21979 and SRI-30052, that were brain penetrant and displayed a favorable therapeutic window analysis of The Cancer Genome Atlas data demonstrated that higher levels of DRD3 (but not DRD2 or DRD4) were associated with worse prognosis in primary, MGMT unmethylated tumors. These data suggested that DRD3 antagonists may remain efficacious in TMZ-resistant GBMs. Indeed, SRI-21979, but not haloperidol, significantly reduced the growth of TMZ-resistant GBM cells. Together our data suggest that DRD3 antagonist-based therapies may provide a novel therapeutic option for the treatment of GBM.

A role for GLUT3 in glioblastoma cell invasion that is not recapitulated by GLUT1.

The multifaceted roles of metabolism in invasion have been investigated across many cancers. The brain tumor glioblastoma (GBM) is a highly invasive and metabolically plastic tumor with an inevitable recurrence. The neuronal glucose transporter 3 (GLUT3) was previously reported to correlate with poor glioma patient survival and be upregulated in GBM cells to promote therapeutic resistance and survival under restricted glucose conditions. It has been suggested that the increased glucose uptake mediated by GLUT3 elevation promotes survival of circulating tumor cells to facilitate metastasis. Here we suggest a more direct role for GLUT3 in promoting invasion that is not dependent upon changes in cell survival or metabolism. Analysis of glioma datasets demonstrated that GLUT3, but not GLUT1, expression was elevated in invasive disease. In human xenograft derived GBM cells, GLUT3, but not GLUT1, elevation significantly increased invasion in transwell assays, but not growth or migration. Further, there were no changes in glycolytic metabolism that correlated with invasive phenotypes. We identified the GLUT3 C-terminus as mediating invasion: substituting the C-terminus of GLUT1 for that of GLUT3 reduced invasion. RNA-seq analysis indicated changes in extracellular matrix organization in GLUT3 overexpressing cells, including upregulation of osteopontin. Together, our data suggest a role for GLUT3 in increasing tumor cell invasion that is not recapitulated by GLUT1, is separate from its role in metabolism and survival as a glucose transporter, and is likely broadly applicable since GLUT3 expression correlates with metastasis in many solid tumors.

Optimizing ceftaroline dosing in critically ill patients undergoing continuous renal replacement therapy.

BACKGROUND AND OBJECTIVES: Currently, no dosing information exists for ceftaroline fosamil in patients undergoing continuous renal replacement therapy (CRRT). The objectives of this study are to characterize the pharmacokinetics of ceftaroline in critically ill patients undergoing CRRT modalities and to derive individualized dosing recommendations. METHODS: This pharmacokinetic study aimed to enroll critically ill patients receiving ceftaroline fosamil and any CRRT modality from adult intensive care units. Selection of the specific CRRT modality and dosing regimen was based on clinical discretion. Pre-filter, post-filter, and ultrafiltrate samples were obtained before the administration of the fourth dose, after the completion of the infusion, and up to five additional time points post-infusion. Plasma concentrations were measured using a validated ultra-high performance liquid chromatography assay. Individual pharmacokinetic parameters were calculated using non-compartmental analysis. RESULTS: Four patients were enrolled to investigate the need for dosing adjustments. The average sieving coefficient for ceftaroline was 0.81 ± 0.1, indicating high filter efficiency. The average volume of distribution was 41.8 L (0.48 L/kg) and is within the previously reported range in patients with normal renal function. Non-renal clearance accounted for more than 50% of the total clearance observed in patients. The observed pharmacokinetic profiles suggest that the pharmacodynamic target for 2-log10  CFU reduction from baseline (%fT >1 mg/L of 50%) was met for each patient. Due to the impact of CRRT and non-renal clearance, dosing recommendations were derived for different ranges of effluent flow rates and adjusted body weights. For a patient with an adjusted body weight of 70 kg and receiving CRRT at an effluent flow rate of 3 L/h, a ceftaroline fosamil dosing regimen of 400 mg every 12 h is proposed. CONCLUSION: Ceftaroline is cleared extensively in critically ill patients receiving CRRT and may impact pharmacodynamic target achievement. Dose adjustments should be based on the intensity of the CRRT regimen, patient weight, and the clinical status of the patient.

HIV Screening Among Gonorrhea-Diagnosed Individuals; Baltimore, Maryland; April 2015 to April 2019.

BACKGROUND: Individuals diagnosed with gonorrhea are at elevated risk for HIV. Per US Centers for Disease Control and Prevention guideline, individuals being evaluated for gonorrhea should be screened for HIV concurrently. There is limited information on HIV screening among gonorrhea-diagnosed individuals across different health care settings. Our objective was to identify potential gaps in HIV screening among gonorrhea-diagnosed individuals in Baltimore City, Maryland. METHODS: We used Sexually Transmitted Disease Surveillance Network project data collected on a random sample of all gonorrhea diagnoses reported to the health department between April 2015 and April 2019. Individuals with known HIV diagnoses were excluded. HIV screening was confirmed through surveys administered to the gonorrhea-diagnosing provider. HIV screening across groups was assessed using Poisson regression models with robust SEs. We examined those with and without recent (≤12 months) sexually transmitted infection (STI) history separately. RESULTS: Among 2830 gonorrhea-diagnosed individuals with completed Sexually Transmitted Disease Surveillance Network provider surveys, less than half (35.2% with and 44.8% without recent STI history) received concurrent HIV screening. HIV screening was 73% less prevalent among those diagnosed in emergency departments/urgent care centers/hospitals versus sexual health clinics (with and without recent STI history: adjusted prevalence ratio, 0.27 [95% confidence interval, 0.19-0.39]; adjusted prevalence ratio, 0.27 [0.23-0.33]), controlling for diagnosis year, sex, race/ethnicity, age, infection site, and insurance. CONCLUSIONS: Our findings suggest a considerable gap in HIV screening among individuals at elevated risk for HIV acquisition in Baltimore City, particularly among those diagnosed in emergency departments/urgent care centers/hospital settings. Future work should focus on identifying provider-level barriers to concurrent HIV/STI screening to inform provider education programs.

The Potential Population-Level Impact of Different Gonorrhea Screening Strategies in Baltimore and San Francisco: An Exploratory Mathematical Modeling Analysis.

BACKGROUND: Baltimore and San Francisco represent high burden areas for gonorrhea in the United States. We explored different gonorrhea screening strategies and their comparative impact in the 2 cities. METHODS: We used a compartmental transmission model of gonorrhea stratified by sex, sexual orientation, age, and race/ethnicity, calibrated to city-level surveillance data for 2010 to 2017. We analyzed the benefits of 5-year interventions which improved retention in care cascade or increased screening from current levels. We also examined a 1-year outreach screening intervention of high-activity populations. RESULTS: In Baltimore, annual screening of population aged 15 to 24 years was the most efficient of the 5-year interventions with 17.9 additional screening tests (95% credible interval [CrI], 11.8-31.4) needed per infection averted while twice annual screening of the same population averted the most infections (5.4%; 95% CrI, 3.1-8.2%) overall with 25.3 (95% CrI, 19.4-33.4) tests per infection averted. In San Francisco, quarter-annual screening of all men who have sex with men was the most efficient with 16.2 additional (95% CrI, 12.5-44.5) tests needed per infection averted, and it also averted the most infections (10.8%; 95% CrI, 1.2-17.8%). Interventions that reduce loss to follow-up after diagnosis improved outcomes. Depending on the ability of a short-term outreach screening to screen populations at higher acquisition risk, such interventions can offer efficient ways to expand screening coverage. CONCLUSIONS: Data on gonorrhea prevalence distribution and time trends locally would improve the analyses. More focused intervention strategies could increase the impact and efficiency of screening interventions.