Effect of maneuvers, diuresis, and fluid administration on ultrasound-measured liver stiffness after Fontan.

BACKGROUND: To determine the effect of stress maneuvers/interventions on ultrasound liver stiffness measurements (LSMs) in patients with Fontan circulation and healthy controls. METHODS: In this prospective, IRB-approved study of 10 patients after Fontan palliation and 10 healthy controls, ultrasound 2D shear-wave elastography LSMs were acquired at baseline and after maximum inspiration, expiration, standing, handgrip, aerobic exercise, i.v. fluid (500 mL normal saline) administration, and i.v. furosemide (20 mg) administration. Absolute and percent change in LSM were compared between baseline and each maneuver, and then from fluid infusion to after diuresis. RESULTS: Median ages were 25.5 and 26 years in the post-Fontan and control groups (p = 0.796). LSMs after Fontan were higher at baseline (2.6 vs. 1.3 m/s) and with all maneuvers compared to controls (all p < 0.001). Changes in LSM with maneuvers, exercise, fluid, or diuresis were not significant when compared to baseline in post-Fontan patients. LSM in controls increased with inspiration (+0.02 m/s, 1.6%, p = 0.03), standing (+0.07 m/s, 5.5%, p = 0.03), and fluid administration (+0.10 m/s, 7.8%, p = 0.002), and decreased 60 minutes after diuretic administration (-0.05 m/s, -3.9%, p = 0.01) compared to baseline. LSM after diuretic administration significantly decreased when compared to after i.v. fluid administration at 30 minutes (-0.79 m/s, -26.5%, p = 0.004) and 60 minutes (-0.78 m/s, -26.2%, p = 0.017) for patients after Fontan and controls at 15 minutes (-0.12 m/s, -8.70%, p = 0.002), 30 minutes (-0.15 m/s, -10.9%, p = 0.003), and 60 minutes (-0.1 m/s, -10.9%, p = 0.005). CONCLUSIONS: LSM after Fontan is higher with more variability compared to controls. Diuresis is associated with significantly decreased liver stiffness in both patients after Fontan and controls, with the suggestion of a greater effect in Fontan patients.

Outcomes of Haplo-Cord Versus Dual Cord Transplants: A Single-Center Retrospective Analysis.

Despite the concurrent use of haploidentical cord (HCT) and dual cord (DCT) stem cell transplant approaches for over a decade, there have been few comparisons of their outcomes. Our objective in this study is to assess for differences in the outcomes and adverse effects associated with HCTs versus DCTs. Here we report a retrospective analysis of HCTs and DCTs at our institution. From October 2012 to October 2022, 70 HCT and 133 DCT transplants were performed following 50 mg/kg of IV cyclophosphamide, 150 mg/m2 of IV fludarabine, 10 mg/kg of IV thiotepa, and 4 Gy total body irradiation conditioning. With a median follow-up of 3.6 years among survivors, there was no difference in overall survival (OS) (3 years OS 65% DCT versus 63% HCT, P = 1) or relapse-free survival (3 years RFS 62% DCT versus 64% HCT, P = .97) for all patients. Time to neutrophil recovery was faster in HCT recipients (median 17 versus 22 days, P = .021), with no difference in platelet recovery to 20,000/µL (P = .12). Median hospitalization for HCT recipients was 20 days versus 24 days for DCT recipients (P < .0001). Engraftment syndrome treated with steroids occurred in 47/133 (35%) DCT recipients versus 42/70 (60%) HCT recipients (odds ratios 0.37, P value=.001). There was a significant increase in grade 3 to 4 acute graft-versus-host disease (aGVHD) in haplo-cord recipients (P = .007), but no difference in grade 2 to 4 aGVHD (P = .11), all chronic GVHD (cGVHD) (P = .9), or moderate-severe cGVHD (P = .3). Our outcomes demonstrate faster engraftment and shorter hospitalization in HCTs relative to DCTs, but more engraftment syndrome and higher grade 3 to 4 aGVHD. When both are options, these factors should guide the choice between HCTs and DCTs.

Impact of Appropriate Use Criteria for Cross-Sectional Imaging on Medical Decision-Making in Patients with Conotruncal Defects.

Associations between Appropriate Use Criteria (AUC) ratings and medical decision-making in congenital heart disease are not well-established. We applied the 2020 AUC for multimodality imaging in follow-up care of pediatric and young adult patients with conotruncal defects to evaluate appropriateness of cardiac magnetic resonance (CMR) and computed tomography (CCT) use in this population and impact on clinical decision-making. Records were reviewed and assigned AUC indications and corresponding ratings for CMR and CCT. We examined the relationship between AUC indications, their ratings, and change in management. Of the 200 studies (133 CMR, 67 CCT) performed on 187 patients, no studies were rated Rarely Appropriate (R), and most studies were obtained for routine follow-up (151/200 [75.5%]) and were not prompted by clinical concerns. There were 70/200 (35.0%) studies which led to management changes; these included transcatheter intervention (29/70 [41.4%]), surgical intervention (25/70 [35.7%]), other interventions (10/70 [14.3%]), and medical intervention (6/70 [8.6%]). Among all studies, studies prompted by clinical concerns and studies rated M more frequently resulted in change in management (46.9 vs 31.1%, p = 0.04 and 54.1 vs 30.7%, p = 0.003, respectively). In conclusion, we found that all studies were ordered for indications rated Appropriate (A) or May be Appropriate (M), indicating compliance in ordering practices as outlined by published AUC. Studies ordered for clinical change or rated M more frequently led to management change in patient care. Findings may help inform provider expectations of testing yield in this population and serve as a platform for development of future iterations of AUC.

Transcriptomic Profiling of Primary Prostate Cancers and Nonlocalized Disease on Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography: A Multicenter Retrospective Study.

PURPOSE: To characterize the relationship between Decipher genomic classifier scores and prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT)-based metastatic spread. MATERIALS AND METHODS: We identified patients from four institutions who underwent PSMA PET/CT scans pretreatment for primary staging or postradical prostatectomy (RP) for suspected recurrence and had Decipher transcriptomic data available from biopsy or RP specimens. PSMA PET/CT-based patterns of spread were classified as localized (miT + N0M0) or nonlocalized (miN1M0 or miM1a-c). We calculated the association between Decipher scores and the risk of nonlocalized disease on PSMA PET/CT using multivariable logistic regression for pretreatment patients and multivariable Cox regression for post-RP patients. We also compared select transcriptomic signatures between patients with localized and nonlocalized diseases. RESULTS: Five hundred eighty-six patients were included (pretreatment: n = 329; post-RP: n = 257). Higher Decipher scores were associated with nonlocalized disease on PSMA PET/CT both pretreatment (odds ratio, 1.18 [95% CI, 1.03 to 1.36] per 0.1 increase in Decipher score, P = .02) and post-RP (hazard ratio, 1.15 [95% CI, 1.05 to 1.27] per 0.1 increase in Decipher score, P = .003). In the pretreatment setting, nonlocalized disease was associated with higher rates of TP53 mutations and lower rates of PAM50 luminal A subtype compared with localized disease. In the post-RP setting, overexpression of signatures related to metabolism, DNA repair, and androgen receptor signaling were associated with higher rates of nonlocalized disease. CONCLUSION: Higher Decipher scores were associated with nonlocalized disease identified on PSMA PET/CT both pretreatment and post-RP. There were several transcriptomic differences between localized and nonlocalized diseases in both settings.

Lysosomal acid lipase A modulates leukemia stem cell response to venetoclax/tyrosine kinase inhibitor combination therapy in blast phase chronic myeloid leukemia.

The treatment of blast phase chronic myeloid leukemia (bpCML) remains a challenge due at least in part to drug resistance of leukemia stem cells (LSCs). Recent clinical evidence suggests that the BCL-2 inhibitor venetoclax in combination with ABL-targeting tyrosine kinase inhibitors (TKIs) can eradicate bpCML LSCs. In this report, we employed preclinical models of bpCML to investigate the efficacy and underlying mechanism of LSC-targeting with venetoclax/TKI combinations. Transcriptional analysis of LSCs exposed to venetoclax and dasatinib revealed upregulation of genes involved in lysosomal biology, in particular lysosomal acid lipase A (LIPA), a regulator of free fatty acids. Metabolomic analysis confirmed increased levels of free fatty acids in response to venetoclax/dasatinib. Pre-treatment of leukemia cells with bafilomycin, a specific lysosome inhibitor, or genetic perturbation of LIPA, resulted in increased sensitivity of leukemia cells toward venetoclax/dasatinib, implicating LIPA in treatment resistance. Importantly, venetoclax/dasatinib treatment does not affect normal stem cell function, suggestive of a leukemia-specific response. These results demonstrate that venetoclax/dasatinib is an LSCselective regimen in bpCML and that disrupting LIPA and fatty acid transport enhances venetoclax/dasatinib response in targeting LSCs, providing a rationale for exploring lysosomal disruption as an adjunct therapeutic strategy to prolong disease remission.

Digital droplet PCR analysis of organoids generated from mouse mammary tumors demonstrates proof-of-concept capture of tumor heterogeneity.

Breast cancer metastases exhibit many different genetic alterations, including copy number amplifications (CNA). CNA are genetic alterations that are increasingly becoming relevant to breast oncology clinical practice. Here we identify CNA in metastatic breast tumor samples using publicly available datasets and characterize their expression and function using a metastatic mouse model of breast cancer. Our findings demonstrate that our organoid generation can be implemented to study clinically relevant features that reflect the genetic heterogeneity of individual tumors.

Targeting Acute Myeloid Leukemia Stem Cells through Perturbation of Mitochondrial Calcium.

Acute myeloid leukemia stem cells (LSCs) are uniquely reliant on oxidative phosphorylation (OXPHOS) for survival. Moreover, maintenance of OXPHOS is dependent on BCL-2, creating a therapeutic opportunity to target LSCs using the BCL-2 inhibitor venetoclax. Although venetoclax-based regimens have shown promising clinical activity, the emergence of drug resistance is prevalent. Thus, in the present study, we investigated how mitochondrial properties may influence venetoclax responsiveness. Our data show that utilization of mitochondrial calcium is fundamentally different between drug-responsive and nonresponsive LSCs. By comparison, venetoclax-resistant LSCs demonstrate an active metabolic (i.e., OXPHOS) status with relatively high levels of calcium. Consequently, we tested genetic and pharmacological approaches to target the mitochondrial calcium uniporter. We demonstrate that inhibition of calcium uptake reduces OXPHOS and leads to eradication of venetoclax-resistant LSCs. These findings demonstrate a central role for calcium signaling in LSCs and provide an avenue for clinical management of venetoclax resistance. Significance: We identify increased utilization of mitochondrial calcium as a distinct metabolic requirement of venetoclax-resistant LSCs and demonstrate the potential of targeting mitochondrial calcium uptake as a therapeutic strategy.

A systematic review and meta-analysis of pathologic complete response rates for patients with cholangiocarcinoma treated on liver transplant protocols.

BACKGROUND AND OBJECTIVES: Many heterogenous orthotopic liver transplant (OLT) protocols exist for patients with unresectable cholangiocarcinoma. Little is known about the incidence, predictors for, and the significance of achieving a pathologic complete response (pCR). METHODS: We performed a systematic review through September 2022 of the PubMed, Embase, and Web of Science databases. A random-effect meta-analysis was conducted to pool data across studies with reported pCR rates. Heterogeneity between treatment protocols was assessed via subgroup analysis. The pCR and 1-, 3-, and 5-year recurrence-free survival (RFS) and overall survival (OS) rates were extracted as outcomes of interest. RESULTS: A total of 15 studies reported pCR rates and were grouped by use of the Mayo protocol (4/15), stereotactic body radiation therapy (2/15), and an Other category (9/15). The pooled pCR rate among all studies was 32%. Both radiation technique and duration of CHT showed no significant association with pCR (p = 0.05 and 0.13, respectively). Pooled 1-year RFS and OS after any neoadjuvant therapy and OLT was 80% (95% confidence interval [CI], 0.61-0.91), and 91% (95% CI, 0.87-0.94), respectively. There was no 1-year OS difference detected among the three groups. pCR was not associated with OS in the meta-regression. Pooled 3- and 5-year OS among all studies was 72% and 61%, respectively. CONCLUSIONS: The pooled incidence of pCR was 32%. Differences in radiation technique did not appear to influence pCR rates and upon meta-regression, pCR was not a surrogate marker for survival.

Antibody targeting of conserved sites of vulnerability on the SARS-CoV-2 spike receptor-binding domain.

Given the continuous emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VoCs), immunotherapeutics that target conserved epitopes on the spike (S) glycoprotein have therapeutic advantages. Here, we report the crystal structure of the SARS-CoV-2 S receptor-binding domain (RBD) at 1.95 Å and describe flexibility and distinct conformations of the angiotensin-converting enzyme 2 (ACE2)-binding site. We identify a set of SARS-CoV-2-reactive monoclonal antibodies (mAbs) with broad RBD cross-reactivity including SARS-CoV-2 Omicron subvariants, SARS-CoV-1, and other sarbecoviruses and determine the crystal structures of mAb-RBD complexes with Ab246 and CR3022 mAbs targeting the class IV site, WRAIR-2134, which binds the recently designated class V epitope, and WRAIR-2123, the class I ACE2-binding site. The broad reactivity of class IV and V mAbs to conserved regions of SARS-CoV-2 VoCs and other sarbecovirus provides a framework for long-term immunotherapeutic development strategies.

Valve-in-Valve Transcatheter Aortic Valve Replacement During Second Trimester of Pregnancy.

Critical bioprosthetic aortic valve stenosis is a rare finding in the second trimester of pregnancy. We present the case of a successful valve-in-valve transcatheter aortic valve replacement in a 16-weeks-pregnant patient. We describe the significant role of the multidisciplinary heart team during preconception and pregnancy.

Targeting Acute Myeloid Leukemia Stem Cells Through Perturbation of Mitochondrial Calcium.

We previously reported that acute myeloid leukemia stem cells (LSCs) are uniquely reliant on oxidative phosphorylation (OXPHOS) for survival. Moreover, maintenance of OXPHOS is dependent on BCL2, creating a therapeutic opportunity to target LSCs using the BCL2 inhibitor drug venetoclax. While venetoclax-based regimens have indeed shown promising clinical activity, the emergence of drug resistance is prevalent. Thus, in the present study, we investigated how mitochondrial properties may influence mechanisms that dictate venetoclax responsiveness. Our data show that utilization of mitochondrial calcium is fundamentally different between drug responsive and non-responsive LSCs. By comparison, venetoclax-resistant LSCs demonstrate a more active metabolic (i.e., OXPHOS) status with relatively high steady-state levels of calcium. Consequently, we tested genetic and pharmacological approaches to target the mitochondrial calcium uniporter, MCU. We demonstrate that inhibition of calcium uptake sharply reduces OXPHOS and leads to eradication of venetoclax-resistant LSCs. These findings demonstrate a central role for calcium signaling in the biology of LSCs and provide a therapeutic avenue for clinical management of venetoclax resistance.

ASSET: Auto-Segmentation of the Seventeen SEgments for Ventricular Tachycardia Ablation in Radiation Therapy.

There has been a recent effort to treat high-risk ventricular tachycardia (VT) patients through radio-ablation. However, manual segmentation of the VT target is complex and time-consuming. This work introduces ASSET, or Auto-segmentation of the Seventeen SEgments for Tachycardia ablation, to aid in radiation therapy (RT) planning. ASSET was retrospectively applied to CTs for 26 thoracic RT patients (13 undergoing VT ablation). The physician-defined parasternal long-axis of the left ventricle (LV) and the axes generated from principal component analysis (PCA) were compared using mean distance to agreement (MDA) and angle of separation. The manually selected right ventricle insertion point and LVs were used to apply the ASSET model to automatically generate the 17 segments of the LV myocardium (LVM). Physician-defined parasternal long-axis differed from PCA by 1.2 ± 0.3 mm MDA and 6.9 ± 0.7 degrees. Segments differed by 0.69 ± 0.29 mm MDA and 0.89 ± 0.03 Dice similarity coefficient. Running ASSET takes <5 min where manual segmentation took >2 h/patient. Agreement between ASSET and expert contours was comparable to inter-observer variability. Qualitative scoring conducted by three experts revealed automatically generated segmentations were clinically useable as-is. ASSET offers efficient and reliable automatic segmentations for the 17 segments of the LVM for target generation in RT planning.

A Novel Type of Monocytic Leukemia Stem Cell Revealed by the Clinical Use of Venetoclax-Based Therapy.

The BCL2 inhibitor venetoclax has recently emerged as an important component of acute myeloid leukemia (AML) therapy. Notably, use of this agent has revealed a previously unrecognized form of pathogenesis characterized by monocytic disease progression. We demonstrate that this form of disease arises from a fundamentally different type of leukemia stem cell (LSC), which we designate as monocytic LSC (m-LSC), that is developmentally and clinically distinct from the more well-described primitive LSC (p-LSC). The m-LSC is distinguished by a unique immunophenotype (CD34-, CD4+, CD11b-, CD14-, CD36-), unique transcriptional state, reliance on purine metabolism, and selective sensitivity to cladribine. Critically, in some instances, m-LSC and p-LSC subtypes can co-reside in the same patient with AML and simultaneously contribute to overall tumor biology. Thus, our findings demonstrate that LSC heterogeneity has direct clinical significance and highlight the need to distinguish and target m-LSCs as a means to improve clinical outcomes with venetoclax-based regimens. SIGNIFICANCE: These studies identify and characterize a new type of human acute myeloid LSC that is responsible for monocytic disease progression in patients with AML treated with venetoclax-based regimens. Our studies describe the phenotype, molecular properties, and drug sensitivities of this unique LSC subclass. This article is featured in Selected Articles from This Issue, p. 1949.

Venetoclax is safe and tolerable as post-transplant maintenance therapy for AML patients at high risk for relapse.

Relapse is the most common cause of mortality in acute myeloid leukemia (AML) patients after allogeneic stem cell transplant (SCT). Post-SCT maintenance strategies that prevent relapse are desirable but must be well tolerated and convenient to administer. We hypothesized single agent venetoclax (ven) may be an effective maintenance therapy among high relapse risk patients. Between February 2019 and December 2021, we administered post-SCT ven maintenance to 49 AML patients at high-risk for relapse as a prospectively defined off-label practice at our institution. Ven was planned to be administered until 1-year post-SCT. While temporary interruptions were common (67.3% of all patients), of those with >1 year follow up, 22/25 (88%) completed the full year of planned therapy. Cytopenias (40.8%) and gastrointestinal adverse events (34.7%) were the most common toxicities. At 1-year post-SCT, overall survival (OS) and relapse-free survival (RFS) were 70% and 67% respectively. Our experience demonstrates single agent ven is a safe, tolerable, and feasible maintenance therapy that may improve RFS and OS in high relapse risk post-SCT patients.

Higher-dose venetoclax with measurable residual disease-guided azacitidine discontinuation in newly diagnosed acute myeloid leukemia.

Venetoclax+azacitidine is the standard of care for newly-diagnosed patients with acute myeloid leukemia (AML) for whom intensive chemotherapy is inappropriate. Efforts to optimize this regimen are necessary. We designed a clinical trial to investigate two hypotheses: i) higher doses of venetoclax are tolerable and more effective, and ii) azacitidine can be discontinued after deep remissions. Forty-two newly diagnosed AML patients were enrolled in the investigator-initiated High Dose Discontinuation Azacitidine+Venetoclax (HiDDAV) Study (clinicaltrials gov. Identifier: NCT03466294). Patients received one to three "induction" cycles of venetoclax 600 mg daily with azacitidine. Responders received MRD-positive or MRDnegative "maintenance" arms: azacitidine with 400 mg venetoclax or 400 mg venetoclax alone, respectively. The toxicity profile of HiDDAV was similar to 400 mg venetoclax. The overall response rate was 66.7%; the duration of response (DOR), event-free survival (EFS) and overall survival were 12.9, 7.8 and 9.8 months, respectively. The MRD negativity rate was 64.3% by flow cytometry and 25.0% when also measured by droplet digital polymerase chain recation. MRD-negative patients by flow cytometry had improved DOR and EFS; more stringent measures of MRD negativity were not associated with improved OS, DOR or EFS. Using MRD to guide azacitidine discontinuation did not lead to improved DOR, EFS or OS compared to patients who discontinued azacitidine without MRD guidance. Within the context of this study design, venetoclax doses >400 mg with azacitidine were well tolerated but not associated with discernible clinical improvement, and MRD may not assist in recommendations to discontinue azacitidine. Other strategies to optimize, and for some patients, de-intensify, venetoclax+azacitidine regimens are needed.

Appropriateness of cardiovascular computed tomography and magnetic resonance imaging in patients with conotruncal defects.

BACKGROUND: To promote the rational use of cardiovascular imaging in patients with congenital heart disease, the American College of Cardiology developed Appropriate Use Criteria (AUC), but its clinical application and pre-release benchmarks have not been evaluated. We aimed to evaluate the appropriateness of indications for cardiovascular magnetic resonance (CMR) and cardiovascular computed tomography (CCT) in patients with conotruncal defects and to identify factors associated with maybe or rarely appropriate (M/R) indications. METHODS: Twelve centers each contributed a median of 147 studies performed prior to AUC publication (01/2020) on patients with conotruncal defects. To incorporate patient characteristics and center-level effects, a hierarchical generalized linear mixed model was used. RESULTS: Of the 1753 studies (80% CMR, and 20% CCT), 16% were rated M/R. Center M/R ranged from 4 to 39%. Infants accounted for 8.4% of studies. In multivariable analyses, patient- and study-level factors associated with M/R rating included: age <1 year (OR 1.90 [1.15-3.13]), truncus arteriosus (vs. tetralogy of Fallot, OR 2.55 [1.5-4.35]), and CCT (vs. CMR, OR 2.67 [1.87-3.83]). None of the provider- or center-level factors reached statistical significance in the multivariable model. CONCLUSIONS: Most CMRs and CCTs ordered for the follow-up care of patients with conotruncal defects were rated appropriate. However, there was significant center-level variation in appropriateness ratings. Younger age, CCT, and truncus arteriosus were independently associated with higher odds of M/R rating. These findings could inform future quality improvement initiatives and further exploration of factors resulting in center-level variation.