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1.
Mol Cancer Ther ; 2024 May 01.
Article in English | MEDLINE | ID: mdl-38691846

ABSTRACT

The treatment of primary central nervous system (CNS) tumors is challenging due to the blood-brain barrier and complex mutational profiles, which is associated with low survival rates. However, recent studies have identified common mutations in gliomas (IDH-WT and mutant, WHO grades II-IV; with grade IV tumors referred to as glioblastomas; GBMs). These mutations drive epigenetic changes, leading to promoter methylation at the NAPRT gene locus, which encodes an enzyme involved in generating NAD+. Importantly, NAPRT-silencing introduces a therapeutic vulnerability to inhibitors targeting another NAD+ biogenesis enzyme, NAMPT, rationalizing a treatment for these malignancies. Multiple systemically-administered NAMPTis have been developed and tested in clinical trials, but dose-limiting toxicities-including bone marrow suppression and retinal toxicity-have limited their efficacy. Here, we report a novel approach for the treatment of NAPRT-silenced GBMs using nanoparticle-encapsulated (NP) NAMPT inhibitors (NAMPTis) administered by convection-enhanced delivery (CED). We demonstrate that GMX1778 (a NAMPTi) can be formulated in degradable polymer NPs with retention of potency for NAMPT inhibition and anticancer activity in vitro, plus sustained drug release in vitro and in vivo. Direct injection of these drugs via CED into the brain is associated with reduced retinal toxicity compared with systemic administration. Finally, we show that CED of NP-encapsulated GMX1778 to NAPRT-silenced intracranial GBM xenografts in mice exhibit significant tumor growth delay and extends survival. These data support an approach to treat gliomas harboring defects in NAD+ metabolism using CED of NP-encapsulated NAMPTis to greatly improve the therapeutic index and treatment efficacy for this class of drugs.

2.
Neuro Oncol ; 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38770568

ABSTRACT

DNA damage response (DDR) mechanisms are critical to maintenance of overall genomic stability, and their dysfunction can contribute to oncogenesis. Significant advances in our understanding of DDR pathways have raised the possibility of developing therapies that exploit these processes. In this expert-driven consensus review, we examine mechanisms of response to DNA damage, progress in development of DDR inhibitors in IDH-wild-type glioblastoma and IDH-mutant gliomas, and other important considerations such as biomarker development, preclinical models, combination therapies, mechanisms of resistance and clinical trial design considerations.

3.
J Am Chem Soc ; 2024 May 30.
Article in English | MEDLINE | ID: mdl-38815248

ABSTRACT

Aberrant DNA repair is a hallmark of cancer, and many tumors display reduced DNA repair capacities that sensitize them to genotoxins. Here, we demonstrate that the differential DNA repair capacities of healthy and transformed tissue may be exploited to obtain highly selective chemotherapies. We show that the novel N3-(2-fluoroethyl)imidazotetrazine "KL-50" is a selective toxin toward tumors that lack the DNA repair protein O6-methylguanine-DNA-methyltransferase (MGMT), which reverses the formation of O6-alkylguanine lesions. We establish that KL-50 generates DNA interstrand cross-links (ICLs) by a multistep process comprising DNA alkylation to generate an O6-(2-fluoroethyl)guanine (O6FEtG) lesion, slow unimolecular displacement of fluoride to form an N1,O6-ethanoguanine (N1,O6EtG) intermediate, and ring-opening by the adjacent cytidine. The slow rate of N1,O6EtG formation allows healthy cells expressing MGMT to reverse the initial O6FEtG lesion before it evolves to N1,O6EtG, thereby suppressing the formation of toxic DNA-MGMT cross-links and reducing the amount of DNA ICLs generated in healthy cells. In contrast, O6-(2-chloroethyl)guanine lesions produced by agents such as lomustine and the N3-(2-chloroethyl)imidazotetrazine mitozolomide rapidly evolve to N1,O6EtG, resulting in the formation of DNA-MGMT cross-links and DNA ICLs in healthy tissue. These studies suggest that careful consideration of the rates of chemical DNA modification and biochemical DNA repair may lead to the identification of other tumor-specific genotoxic agents.

5.
RSC Adv ; 14(18): 12313-12322, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38633501

ABSTRACT

The study presents a novel, one-pot, and scalable solid-state reaction scheme to prepare bismuth sulphide (Bi2S3)-reduced graphene oxide (rGO) nanocomposites using bismuth oxide (Bi2O3), thiourea (TU), and graphene oxide (GO) as starting materials for energy storage applications. The impact of GO loading concentration on the electrochemical performance of the nanocomposites was investigated. The reaction follows a diffusion substitution pathway, gradually transforming Bi2O3 powder into Bi2S3 nanostrips, concurrently converting GO into rGO. Enhanced specific capacitances were observed across all nanocomposite samples, with the Bi2S3@0.2rGO exhibiting the highest specific capacitance of 705 F g-1 at a current density of 1 A g-1 and maintaining a capacitance retention of 82% after 1000 cycles. The superior specific capacitance is attributed to the excellent homogeneity and synergistic relation between rGO and Bi2S3 nanostrips. This methodology holds promise for extending the synthesis of other chalcogenides-rGO nanocomposites.

6.
iScience ; 27(3): 109280, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38444606

ABSTRACT

Chitinases and ecdysteroid hormones are vital for insect development. Crosstalk between chitin and ecdysteroid metabolism regulation is enigmatic. Here, we examined chitinase inhibition effect on Spodoptera frugiperda ecdysteroid metabolism. In vitro studies suggested that berberine inhibits S. frugiperda chitinase 5 (SfCht5). The Berberine feeding resulted in defective S. frugiperda development. Berberine-fed insects showed higher SfCht5 and Chitinase 7 expression and cumulative chitinase activity. Chitinase inhibition led to overexpression of chitinases, ecdysteroid biosynthesis, and responsive genes. SfCht5 silencing and overexpression resulted in ecdysone receptor deregulation. Transcription factors, like Broad Complex Z4, regulate the ecdysteroid metabolism and showed high expression upon berberine ingestion. Broad Complex Z4 binding in 5' UTR of Ecdysone receptor, SfCht5, Chitinase 7, Phantom, Neverland, and other ecdysteroid biosynthesis genes might lead to their upregulation in berberine-fed insects. As a result, berberine-fed insects showed ecdysone overaccumulation. These findings underscore chitinase activity's impact on ecdysone biosynthesis and its transcriptional crosstalk.

8.
Pediatr Crit Care Med ; 25(4): 288-300, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38236083

ABSTRACT

OBJECTIVES: To characterize immunocompromised-associated pediatric acute respiratory distress syndrome (I-PARDS) and contrast it to PARDS. DESIGN: This is a secondary analysis of the 2016-2017 PARDS incidence and epidemiology (PARDIE) study, a prospective observational, cross-sectional study of children with PARDS. SETTING: Dataset of 145 PICUs across 27 countries. PATIENTS: During 10 nonconsecutive weeks (from May 2016 to June 2017), data about immunocompromising conditions (ICCs, defined as malignancy, congenital/acquired immunodeficiency, posttransplantation, or diseases requiring immunosuppression) were collected. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 708 subjects, 105 (14.8%) had ICC. Before the development of I-PARDS, those with ICC were more likely to be hospitalized (70% vs. 35%, p < 0.001), have more at-risk for PARDS ( p = 0.046), and spent more hours at-risk (20 [interquartile range, IQR: 8-46] vs. 11 [IQR: 4-33], [ p = 0.002]). Noninvasive ventilation (NIV) use was more common in those with ICC ( p < 0.001). Of those diagnosed with PARDS on NIV ( n = 161), children with ICC were more likely to be subsequently intubated ( n = 28/40 [70%] vs n = 53/121 [44%], p = 0.004). Severe PARDS was more common (32% vs 23%, p < 0.001) in I-PARDS. Oxygenation indices were higher at diagnosis and had less improvement over the first 3 days of PARDS ( p < 0.001). Children with I-PARDS had greater nonpulmonary organ dysfunction. Adjusting for Pediatric Risk of Mortality IV and oxygenation index, children with I-PARDS had a higher severity of illness-adjusted PICU mortality (adjusted hazard ratio: 3.0 [95% CI, 1.9-4.7] p < 0.001) and were less likely to be extubated alive within 28 days (subdistribution hazard ratio: 0.47 [95% CI, 0.31-0.71] p < 0.001). CONCLUSIONS: I-PARDS is a unique subtype of PARDS associated with hospitalization before diagnosis and increased: time at-risk for PARDS, NIV use, hypoxia, nonpulmonary organ dysfunction, and mortality. The opportunity for early detection and intervention seems to exist. Dedicated study in these patients is imperative to determine if targeted interventions will benefit these unique patients with the ultimate goal of improving outcomes.


Subject(s)
Multiple Organ Failure , Respiratory Distress Syndrome , Child , Humans , Prospective Studies , Incidence , Cross-Sectional Studies , Respiration, Artificial/adverse effects
9.
Clin Gastroenterol Hepatol ; 22(2): 368-376.e4, 2024 02.
Article in English | MEDLINE | ID: mdl-37802268

ABSTRACT

BACKGROUND & AIMS: The evolution of complicated pediatric Crohn's disease (CD) in the era of anti-tumor necrosis factor (aTNF) therapy continues to be described. Because CD progresses from inflammatory to stricturing (B2) and penetrating (B3) disease behaviors in a subset of patients, we aimed to understand the risk of developing complicated disease behavior or undergoing surgery in relation to aTNF timing and body mass index z-score (BMIz) normalization. METHODS: Multicenter, 5-year longitudinal data from 1075 newly diagnosed CD patients were analyzed. Descriptive statistics, univariate and stepwise multivariate Cox proportional hazard regression (CPHR), and log-rank analyses were performed for risk of surgery and complicated disease behaviors. Differential gene expression from ileal bulk RNA sequencing was correlated with outcomes. RESULTS: Stricturing complications had the largest increase: from 2.98% to 10.60% over 5 years. Multivariate CPHR showed aTNF exposure within 3 months from diagnosis (hazard ratio [HR], 0.33; 95% CI, 0.15-0.71) and baseline L2 disease (HR, 0.29; 95% CI, 0.09-0.92) to be associated with reduced B1 to B2 progression. For children with a low BMIz at diagnosis (n = 294), multivariate CPHR showed BMIz normalization within 6 months of diagnosis (HR, 0.47; 95% CI, 0.26-0.85) and 5-aminosalicyclic acid exposure (HR, 0.32; 95% CI, 0.13-0.81) were associated with a decreased risk for surgery while B2 (HR, 4.20; 95% CI, 1.66-10.65) and B2+B3 (HR, 8.24; 95% CI, 1.08-62.83) at diagnosis increased surgery risk. Patients without BMIz normalization were enriched for genes in cytokine production and inflammation. CONCLUSIONS: aTNF exposure up to 3 months from diagnosis may reduce B2 progression. In addition, lack of BMIz normalization within 6 months of diagnosis is associated with increased surgery risk and a proinflammatory transcriptomic profile.


Subject(s)
Crohn Disease , Child , Humans , Body Mass Index , Risk Factors , Crohn Disease/complications , Tumor Necrosis Factor-alpha , Constriction, Pathologic/etiology , Necrosis , Disease Progression , Retrospective Studies
10.
Open Forum Infect Dis ; 10(12): ofad590, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38094665

ABSTRACT

Antimicrobial resistance in Mycoplasma genitalium is rising globally and antimicrobial options are limited. We evaluated the efficacy of sitafloxacin regimens for macrolide-resistant M genitalium at Melbourne Sexual Health Centre, Australia, between January 2017 and February 2022. Before June 2017, patients received doxycycline followed by sitafloxacin; subsequently, patients received doxycycline followed by combined doxycycline + sitafloxacin. Of 229 patients treated with a sitafloxacin regimen, 80.6% experienced microbial cure. Sitafloxacin cured 94.2% of infections that had not previously failed moxifloxacin and 69.5% of infections that had; prior failure of moxifloxacin was associated with an 8-fold odds of sitafloxacin failure. There was no difference in cure between sequential monotherapy and combination therapy when patients were stratified by past failure of moxifloxacin (P > .05); however, small numbers limited comparisons. Sitafloxacin was well tolerated and still achieved 70% cure in patients in whom moxifloxacin had failed. These data highlight the benefit of incorporating relevant fluoroquinolone resistance markers into assays to assist clinical decision making.

11.
Kidney Int Rep ; 8(12): 2690-2700, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38106571

ABSTRACT

Introduction: Critically ill admitted patients are at high risk of acute kidney injury (AKI). The renal angina index (RAI) and urinary biomarker neutrophil gelatinase-associated lipocalin (uNGAL) can aid in AKI risk assessment. We implemented the Trial in AKI using NGAL and Fluid Overload to optimize CRRT Use (TAKING FOCUS 2; TF2) to personalize fluid management and continuous renal replacement therapy (CRRT) initiation based on AKI risk and patient fluid accumulation. We compared outcomes pre-TF2 and post-TF2 initiation. Methods: Patients admitted from July 2017 were followed-up prospectively with the following: (i) an automated RAI result at 12 hours of admission, (ii) a conditional uNGAL order for RAI ≥8, and (iii) a CRRT initiation goal at 10% to 15% weight-based fluid accumulation. Results: A total of 286 patients comprised 304 intensive care unit (ICU) RAI+ admissions; 178 patients received CRRT over the observation period (2014-2021). Median time from ICU admission to CRRT initiation was 2 days shorter (P < 0.002), and ≥15% pre-CRRT fluid accumulation rate was lower in the TF2 era (P < 0.02). TF2 ICU length of stay (LOS) after CRRT discontinuation and total ICU LOS were 6 and 11 days shorter for CRRT survivors (both P < 0.02). Survival rates to ICU discharge after CRRT discontinuation were higher in the TF2 era (P = 0.001). These associations persisted in each TF2 year; we estimate a conservative $12,500 health care cost savings per CRRT patient treated after TF2 implementation. Conclusion: We suggest that automated clinical decision support (CDS) combining risk stratification and AKI biomarker assessment can produce durable reductions in pediatric CRRT patient morbidity.

12.
World J Diabetes ; 14(10): 1463-1477, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37970124

ABSTRACT

There is a recent increase in the worldwide prevalence of both obesity and diabetes. In this review we assessed insulin signaling, genetics, environment, lipid metabolism dysfunction and mitochondria as the major determinants in diabetes and to identify the potential mechanism of gut microbiota in diabetes diseases. We searched relevant articles, which have key information from laboratory experiments, epidemiological evidence, clinical trials, experimental models, meta-analysis and review articles, in PubMed, MEDLINE, EMBASE, Google scholars and Cochrane Controlled Trial Database. We selected 144 full-length articles that met our inclusion and exclusion criteria for complete assessment. We have briefly discussed these associations, challenges, and the need for further research to manage and treat diabetes more efficiently. Diabetes involves the complex network of physiological dysfunction that can be attributed to insulin signaling, genetics, environment, obesity, mitochondria and stress. In recent years, there are intriguing findings regarding gut microbiome as the important regulator of diabetes. Valid approaches are necessary for speeding medical advances but we should find a solution sooner given the burden of the metabolic disorder - What we need is a collaborative venture that may involve laboratories both in academia and industries for the scientific progress and its application for the diabetes control.

13.
Sci Transl Med ; 15(720): eadi1617, 2023 11.
Article in English | MEDLINE | ID: mdl-37910601

ABSTRACT

The morbidity associated with pediatric medulloblastoma, in particular in patients who develop leptomeningeal metastases, remains high in the absence of effective therapies. Administration of substances directly into the cerebrospinal fluid (CSF) is one approach to circumvent the blood-brain barrier and focus delivery of drugs to the site of tumor. However, high rates of CSF turnover prevent adequate drug accumulation and lead to rapid systemic clearance and toxicity. Here, we show that PLA-HPG nanoparticles, made with a single-emulsion, solvent evaporation process, can encapsulate talazoparib, a PARP inhibitor (BMN-673). These degradable polymer nanoparticles improve the therapeutic index when delivered intrathecally and lead to sustained drug retention in the tumor as measured with PET imaging and fluorescence microscopy. We demonstrate that administration of these particles into the CSF, alone or in combination with systemically administered temozolomide, is a highly effective therapy for tumor regression and prevention of leptomeningeal spread in xenograft mouse models of medulloblastoma. These results provide a rationale for harnessing nanoparticles for the delivery of drugs limited by brain penetration and therapeutic index and demonstrate important advantages in tolerability and efficacy for encapsulated drugs delivered locoregionally.


Subject(s)
Antineoplastic Agents , Cerebellar Neoplasms , Medulloblastoma , Nanoparticles , Child , Humans , Mice , Animals , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Medulloblastoma/drug therapy , Antineoplastic Agents/therapeutic use , Cerebellar Neoplasms/drug therapy , Cerebrospinal Fluid
14.
J Hosp Med ; 18(11): 978-985, 2023 11.
Article in English | MEDLINE | ID: mdl-37792360

ABSTRACT

BACKGROUND: Optimal design of healthcare spaces can enhance patient care. We applied design thinking and human factors principles to optimize communication and signage on high risk patients to improve situation awareness in a new clinical space for the pediatric ICU. OBJECTIVE: To assess the impact of these tools in mitigating situation awareness concerns within the new clinical space. We hypothesized that implementing these design-informed tools would either maintain or improve situation awareness. DESIGN, SETTINGS, AND PARTICIPANTS: A 15-week design thinking process was employed, involving research, ideation, and refinement to develop and implement new situation awareness tools. The process included engagement with interprofessional clinical teams, scenario planning, workflow mapping, iterative feedback collection, and collaboration with an industry partner for signage development and implementation. INTERVENTION: Improved and updated communication devices and bedside mitigation plans. MAIN OUTCOME AND MEASURES: Process metrics included individual and shared situation awareness of PICU care teams and our patient outcome metric was the rate of cardiopulmonary resuscitation (CPR) events pre- and post-transition. RESULTS: When evaluating all patients, shared situation awareness for accurate high-risk status improved from 81% pre-transition to 92% post-transition (p = .006). When assessing individual care team roles, accuracy of patient high-risk status improved from 88% to 95% (p = .05) for RNs, 85% to 96% (p = .003) for residents, and 88% to 95% (p = .03) for RTs. There was no change in the rate of CPR events following the transition.


Subject(s)
Awareness , Patient Care Team , Child , Humans , Intensive Care Units, Pediatric , Health Facilities
15.
Crit Care Explor ; 5(9): e0978, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37711646

ABSTRACT

OBJECTIVES: To describe our institutional experience utilizing adjunctive synthetic angiotensin II in critically ill children with catecholamine-resistant vasodilatory shock (CRVS). DESIGN: Single-center, retrospective case series. SETTING: PICU and cardiac ICU (CICU) at a large, quaternary children's hospital in the United States. PATIENTS: Twenty-three pediatric patients with CRVS who were prescribed synthetic angiotensin II at the discretion of bedside clinicians from January 2018 to April 2023. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Twenty-three patients (20 in PICU, 3 in CICU) with a median age of 10.4 years (interquartile range [IQR] 1.5-18.5) received angiotensin II over the study period, 70% of whom died. At the time of angiotensin II initiation, 17 patients (74%) were receiving one or more forms of extracorporeal therapy, and median Pediatric Logistic Organ Dysfunction-2 Score-2 in the prior 24 hours was 9 (IQR 7-11). The median time between initiation of the first vasoactive agent and angiotensin II was 127 hours (IQR 13-289), and the median total norepinephrine equivalent (NED) at initiation was 0.65 µg/kg/min (IQR 0.36-0.78). The median duration of therapy was 27 hours (IQR 4-68), and at each timepoint assessed, patients had median improvement in NED and mean arterial pressure (MAP) with treatment. Survivors initiated angiotensin II nearly 3 days earlier in vasoactive course (91.5 hr vs 161 hr, p = 0.23), and had both greater reduction in NED (-75% [IQR -96 to -50] vs +2.1% [IQR -55 to 33], p = 0.008) and greater increase in MAP (+15 mm Hg [IQR 10-27] vs -1.5 mm Hg [IQR -27 to 18], p = 0.052) at angiotensin II discontinuation. CONCLUSIONS: We demonstrate reduction in NED and improved MAP following initiation of angiotensin II in critically ill children with CRVS. Further prospective work is needed to examine optimal timing of angiotensin II initiation, appropriate patient selection, and safety in this population.

17.
Open Forum Infect Dis ; 10(8): ofad427, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37608915

ABSTRACT

Background: High levels of macrolide resistance and increasing fluoroquinolone resistance are making Mycoplasma genitalium increasingly difficult to treat. Minocycline is an alternative treatment for patients with macrolide-resistant M genitalium infections that have failed moxifloxacin, or for those with fluoroquinolone contraindications or resistance. Published efficacy data for minocycline for M genitalium are limited. Methods: We evaluated minocycline 100 mg twice daily for 14 days at Melbourne Sexual Health Centre (MSHC). Microbial cure was defined as a negative test of cure within 14-90 days after completing minocycline. The proportion cured and 95% confidence intervals (CIs) were calculated, and logistic regression was used to explore factors associated with treatment failure. We pooled data from the current study with a prior adjacent case series of patients with M genitalium who had received minocycline 100 mg twice daily for 14 days at MSHC. Results: Minocycline cured 60 of 90 (67% [95% CI, 56%-76%]) infections. Adherence was high (96%) and side effects were mild and self-limiting. No demographic or clinical characteristics were associated with minocycline failure in regression analyses. In the pooled analyses of 123 patients, 83 (68% [95% CI, 58%-76%]) were cured following minocycline. Conclusions: Minocycline cured 68% of macrolide-resistant M genitalium infections. These data provide tighter precision around the efficacy of minocycline for macrolide-resistant M genitalium and show that it is a well-tolerated regimen. With high levels of macrolide resistance, increasing fluoroquinolone resistance, and the high cost of moxifloxacin, access to nonquinolone options such as minocycline is increasingly important for the clinical management of M genitalium.

18.
Chem Commun (Camb) ; 59(60): 9231-9234, 2023 Jul 25.
Article in English | MEDLINE | ID: mdl-37417451

ABSTRACT

A simple and efficient solvent-free protocol for continuous flow synthesis of amides at room temperature is developed using easily available starting materials. N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC.HCl) was used as the reagent for the formation of an amide bond without using any metal catalyst or additives. A jacketed screw reactor when operated over a residence time of 30 300 s helped achieve almost complete conversion. This approach is extended for the synthesis of 36 derivatives and 2 bioactive molecules using different substrates having different aliphatic mono and di-acids as well as aromatic acids, including aromatic hetero-acid compounds and phenyl hydrazine. The target amide was scaled up to 100 g with an average 90% yield.

19.
Sex Health ; 20(5): 390-402, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37423606

ABSTRACT

BACKGROUND: The first mpox case was reported in May 2022 in Australia. Most cases have been diagnosed in men who have sex with men (MSM). This study aimed to examine community understanding of mpox, attitudes towards vaccination, and potential changes in sexual practices surrounding the mpox outbreak among MSM and transgender people in Victoria, Australia. METHODS: Participants were recruited from sexual health clinics and communities in Victoria, Australia, in August-October 2022. Participants were asked about their understanding and knowledge of mpox, vaccination uptake and intentions to change sexual practices. Univariable and multivariable logistic regression was performed to examine the factors associated with mpox vaccine uptake. RESULTS: Most participants (97.8%, 525/537) had heard about mpox and 10.5% (55/525) knew someone who had had mpox. Of the 12 mpox knowledge questions, the median score of correct answers was 10 (IQR=8-11) out of a maximum of 12. More than a third (36.6%, 191/522) had been vaccinated against mpox. MSM who had a good knowledge of mpox had the highest odds of receiving mpox vaccine compared with those who had poor knowledge (aOR=4.05; 95% CI: 1.54-10.61). To prevent mpox, half reported they would reduce having sex with casual partners, stop having chemsex (used drugs for the purpose of sex), stop attending sex-on-premises-venues, and stop having group sex. A quarter reported they would increase condom use for anal sex. CONCLUSIONS: One-third of high-risk participants and a substantial proportion of participants intended to reduce or stop certain practices, which may explain the large reduction in mpox cases.

20.
Cancer Res Commun ; 3(6): 1132-1139, 2023 06.
Article in English | MEDLINE | ID: mdl-37387791

ABSTRACT

Purpose: O6-methylguanine DNA methyltransferase (MGMT)-silenced tumors reveal sensitivity to temozolomide (TMZ), which may be enhanced by PARP inhibitors. Approximately 40% of colorectal cancer has MGMT silencing and we aimed to measure antitumoral and immunomodulatory effects from TMZ and olaparib in colorectal cancer. Experimental Design: Patients with advanced colorectal cancer were screened for MGMT promoter hypermethylation using methylation-specific PCR of archival tumor. Eligible patients received TMZ 75 mg/m2 days 1-7 with olaparib 150 mg twice daily every 21 days. Pretreatment tumor biopsies were collected for whole-exome sequencing (WES), and multiplex quantitative immunofluorescence (QIF) of MGMT protein expression and immune markers. Results: MGMT promoter hypermethylation was detected in 18/51 (35%) patients, 9 received study treatment with no objective responses, 5/9 had stable disease (SD) and 4/9 had progressive disease as best response. Three patients had clinical benefit: carcinoembryonic antigen reduction, radiographic tumor regression, and prolonged SD. MGMT expression by multiplex QIF revealed prominent tumor MGMT protein from 6/9 patients without benefit, while MGMT protein was lower in 3/9 with benefit. Moreover, benefitting patients had higher baseline CD8+ tumor-infiltrating lymphocytes. WES revealed 8/9 patients with MAP kinase variants (7 KRAS and 1 ERBB2). Flow cytometry identified peripheral expansion of effector T cells. Conclusions: Our results indicate discordance between MGMT promoter hypermethylation and MGMT protein expression. Antitumor activity seen in patients with low MGMT protein expression, supports MGMT protein as a predictor of alkylator sensitivity. Increased CD8+ TILs and peripheral activated T cells, suggest a role for immunostimulatory combinations. Significance: TMZ and PARP inhibitors synergize in vitro and in vivo in tumors with MGMT silencing. Up to 40% of colorectal cancer is MGMT promoter hypermethylated, and we investigated whether TMZ and olaparib are effective in this population. We also measured MGMT by QIF and observed efficacy only in patients with low MGMT, suggesting quantitative MGMT biomarkers more accurately predict benefit to alkylator combinations.


Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Rectal Neoplasms , Humans , Temozolomide/pharmacology , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , DNA Repair , O(6)-Methylguanine-DNA Methyltransferase , Colorectal Neoplasms/drug therapy , Alkylating Agents
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