Diverse tumorigenic consequences of human papillomavirus integration in primary oropharyngeal cancers.

Human papillomavirus (HPV) causes 5% of all cancers and frequently integrates into host chromosomes. The HPV oncoproteins E6 and E7 are necessary but insufficient for cancer formation, indicating that additional secondary genetic events are required. Here, we investigate potential oncogenic impacts of virus integration. Analysis of 105 HPV-positive oropharyngeal cancers by whole-genome sequencing detects virus integration in 77%, revealing five statistically significant sites of recurrent integration near genes that regulate epithelial stem cell maintenance (i.e., SOX2, TP63, FGFR, MYC) and immune evasion (i.e., CD274). Genomic copy number hyperamplification is enriched 16-fold near HPV integrants, and the extent of focal host genomic instability increases with their local density. The frequency of genes expressed at extreme outlier levels is increased 86-fold within ±150 kb of integrants. Across 95% of tumors with integration, host gene transcription is disrupted via intragenic integrants, chimeric transcription, outlier expression, gene breaking, and/or de novo expression of noncoding or imprinted genes. We conclude that virus integration can contribute to carcinogenesis in a large majority of HPV-positive oropharyngeal cancers by inducing extensive disruption of host genome structure and gene expression.

Human papillomavirus and the landscape of secondary genetic alterations in oral cancers.

Human papillomavirus (HPV) is a necessary but insufficient cause of a subset of oral squamous cell carcinomas (OSCCs) that is increasing markedly in frequency. To identify contributory, secondary genetic alterations in these cancers, we used comprehensive genomics methods to compare 149 HPV-positive and 335 HPV-negative OSCC tumor/normal pairs. Different behavioral risk factors underlying the two OSCC types were reflected in distinctive genomic mutational signatures. In HPV-positive OSCCs, the signatures of APOBEC cytosine deaminase editing, associated with anti-viral immunity, were strongly linked to overall mutational burden. In contrast, in HPV-negative OSCCs, T>C substitutions in the sequence context 5'-ATN-3' correlated with tobacco exposure. Universal expression of HPV E6*1 and E7 oncogenes was a sine qua non of HPV-positive OSCCs. Significant enrichment of somatic mutations was confirmed or newly identified in PIK3CA, KMT2D, FGFR3, FBXW7, DDX3X, PTEN, TRAF3, RB1, CYLD, RIPK4, ZNF750, EP300, CASZ1, TAF5, RBL1, IFNGR1, and NFKBIA Of these, many affect host pathways already targeted by HPV oncoproteins, including the p53 and pRB pathways, or disrupt host defenses against viral infections, including interferon (IFN) and nuclear factor kappa B signaling. Frequent copy number changes were associated with concordant changes in gene expression. Chr 11q (including CCND1) and 14q (including DICER1 and AKT1) were recurrently lost in HPV-positive OSCCs, in contrast to their gains in HPV-negative OSCCs. High-ranking variant allele fractions implicated ZNF750, PIK3CA, and EP300 mutations as candidate driver events in HPV-positive cancers. We conclude that virus-host interactions cooperatively shape the unique genetic features of these cancers, distinguishing them from their HPV-negative counterparts.

Inferring clonal heterogeneity in cancer using SNP arrays and whole genome sequencing.

MOTIVATION: Clonal heterogeneity is common in many types of cancer, including chronic lymphocytic leukemia (CLL). Previous research suggests that the presence of multiple distinct cancer clones is associated with clinical outcome. Detection of clonal heterogeneity from high throughput data, such as sequencing or single nucleotide polymorphism (SNP) array data, is important for gaining a better understanding of cancer and may improve prediction of clinical outcome or response to treatment. Here, we present a new method, CloneSeeker, for inferring clinical heterogeneity from sequencing data, SNP array data, or both. RESULTS: We generated simulated SNP array and sequencing data and applied CloneSeeker along with two other methods. We demonstrate that CloneSeeker is more accurate than existing algorithms at determining the number of clones, distribution of cancer cells among clones, and mutation and/or copy numbers belonging to each clone. Next, we applied CloneSeeker to SNP array data from samples of 258 previously untreated CLL patients to gain a better understanding of the characteristics of CLL tumors and to elucidate the relationship between clonal heterogeneity and clinical outcome. We found that a significant majority of CLL patients appear to have multiple clones distinguished by copy number alterations alone. We also found that the presence of multiple clones corresponded with significantly worse survival among CLL patients. These findings may prove useful for improving the accuracy of prognosis and design of treatment strategies. AVAILABILITY AND IMPLEMENTATION: Code available on R-Forge: https://r-forge.r-project.org/projects/CloneSeeker/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Differential gene expression in non-adherent heart transplant survivors: Implications for regulatory T-cell expression.

Survival despite prolonged non-adherence with immunosuppression is rare but has been reported in kidney, lung, and liver transplantation. Its occurrence in heart transplantation is quite rare. Our study was prompted by an index patient who survived despite prolonged medication non-adherence. Prospective consent and blood collection were conducted for seven additional patients who presented in a similar fashion. The blood of patients who were diagnosed with rejection, stable early post-transplant, and stable more than 5 years post-transplant were all compared with a custom gene array focusing on T-regulatory cell processes. The two genes that were differentially expressed in every comparison were TGF beta and RNASEN with very low expression in the rejector group. The prolonged non-adherent group had the maximum expression for TGF beta but average RNASEN expression as compared to the low expression for rejectors and high for post-5 years patients. The patients presented survived for varying lengths of time without immunosuppression. The gene array analysis showed intriguing differences between these rare patients and important patient cohorts. Further efforts should be directed to finding and studying more patients who survive despite lack of prescribed immunosuppression. The mechanisms underlying this phenomenon may inform future advances in transplant immunosuppression.

Shared Genetic Predisposition in Peripartum and Dilated Cardiomyopathies.

Background Peripartum cardiomyopathy shares some clinical features with idiopathic dilated cardiomyopathy, a disorder caused by mutations in more than 40 genes, including TTN, which encodes the sarcomere protein titin. Methods In 172 women with peripartum cardiomyopathy, we sequenced 43 genes with variants that have been associated with dilated cardiomyopathy. We compared the prevalence of different variant types (nonsense, frameshift, and splicing) in these women with the prevalence of such variants in persons with dilated cardiomyopathy and with population controls. Results We identified 26 distinct, rare truncating variants in eight genes among women with peripartum cardiomyopathy. The prevalence of truncating variants (26 in 172 [15%]) was significantly higher than that in a reference population of 60,706 persons (4.7%, P=1.3×10(-7)) but was similar to that in a cohort of patients with dilated cardiomyopathy (55 of 332 patients [17%], P=0.81). Two thirds of identified truncating variants were in TTN, as seen in 10% of the patients and in 1.4% of the reference population (P=2.7×10(-10)); almost all TTN variants were located in the titin A-band. Seven of the TTN truncating variants were previously reported in patients with idiopathic dilated cardiomyopathy. In a clinically well-characterized cohort of 83 women with peripartum cardiomyopathy, the presence of TTN truncating variants was significantly correlated with a lower ejection fraction at 1-year follow-up (P=0.005). Conclusions The distribution of truncating variants in a large series of women with peripartum cardiomyopathy was remarkably similar to that found in patients with idiopathic dilated cardiomyopathy. TTN truncating variants were the most prevalent genetic predisposition in each disorder.

Thirty biologically interpretable clusters of transcription factors distinguish cancer type.

BACKGROUND: Transcription factors are essential regulators of gene expression and play critical roles in development, differentiation, and in many cancers. To carry out their regulatory programs, they must cooperate in networks and bind simultaneously to sites in promoter or enhancer regions of genes. We hypothesize that the mRNA co-expression patterns of transcription factors can be used both to learn how they cooperate in networks and to distinguish between cancer types. RESULTS: We recently developed a new algorithm, Thresher, that combines principal component analysis, outlier filtering, and von Mises-Fisher mixture models to cluster genes (in this case, transcription factors) based on expression, determining the optimal number of clusters in the process. We applied Thresher to the RNA-Seq expression data of 486 transcription factors from more than 10,000 samples of 33 kinds of cancer studied in The Cancer Genome Atlas (TCGA). We found that 30 clusters of transcription factors from a 29-dimensional principal component space were able to distinguish between most cancer types, and could separate tumor samples from normal controls. Moreover, each cluster of transcription factors could be either (i) linked to a tissue-specific expression pattern or (ii) associated with a fundamental biological process such as cell cycle, angiogenesis, apoptosis, or cytoskeleton. Clusters of the second type were more likely also to be associated with embryonically lethal mouse phenotypes. CONCLUSIONS: Using our approach, we have shown that the mRNA expression patterns of transcription factors contain most of the information needed to distinguish different cancer types. The Thresher method is capable of discovering biologically interpretable clusters of genes. It can potentially be applied to other gene sets, such as signaling pathways, to decompose them into simpler, yet biologically meaningful, components.

Circulating T-Cell Subsets, Monocytes, and Natural Killer Cells in Peripartum Cardiomyopathy: Results From the Multicenter IPAC Study.

OBJECTIVE: The aim of this work was to evaluate the hypothesis that the distribution of circulating immune cell subsets, or their activation state, is significantly different between peripartum cardiomyopathy (PPCM) and healthy postpartum (HP) women. BACKGROUND: PPCM is a major cause of maternal morbidity and mortality, and an immune-mediated etiology has been hypothesized. Cellular immunity, altered in pregnancy and the peripartum period, has been proposed to play a role in PPCM pathogenesis. METHODS: The Investigation of Pregnancy-Associated Cardiomyopathy (IPAC) study enrolled 100 women presenting with a left ventricular ejection fraction of <0.45 within 2 months of delivery. Peripheral T-cell subsets, natural killer (NK) cells, and cellular activation markers were assessed by flow cytometry in PPCM women early (<6 wk), 2 months, and 6 months postpartum and compared with those of HP women and women with non-pregnancy-associated recent-onset cardiomyopathy (ROCM). RESULTS: Entry NK cell levels (CD3-CD56+CD16+; reported as % of CD3- cells) were significantly (P < .0003) reduced in PPCM (6.6 ± 4.9% of CD3- cells) compared to HP (11.9 ± 5%). Of T-cell subtypes, CD3+CD4-CD8-CD38+ cells differed significantly (P < .004) between PPCM (24.5 ± 12.5% of CD3+CD4-CD8- cells) and HP (12.5 ± 6.4%). PPCM patients demonstrated a rapid recovery of NK and CD3+CD4-CD8-CD38+ cell levels. However, black women had a delayed recovery of NK cells. A similar reduction of NK cells was observed in women with ROCM. CONCLUSIONS: Compared with HP control women, early postpartum PPCM women show significantly reduced NK cells, and higher CD3+CD4-CD8-CD38+ cells, which both normalize over time postpartum. The mechanistic role of NK cells and "double negative" (CD4-CD8-) T regulatory cells in PPCM requires further investigation.

E3 Ubiquitin Ligase Cbl-b Regulates Thymic-Derived CD4+CD25+ Regulatory T Cell Development by Targeting Foxp3 for Ubiquitination.

CD28 costimulation is essential for the development of thymic-derived CD4(+)CD25(+)Foxp3(+) regulatory T cells ("tTregs"). E3 ubiquitin ligase Cbl-b has been shown to regulate CD28 dependence of T cell activation. In this paper, we report that the loss of Cbl-b partially but significantly rescues the defective development of tTregs in Cd28(-/-) mice. This partial rescue is independent of IL-2. Mechanistically, Cbl-b binds to Foxp3 upon TCR stimulation and, together with Stub1, targets Foxp3 for ubiquitination and subsequently degradation in the proteasome. As Cbl-b self-ubiquitination and proteasomal degradation is impaired in Cd28(-/-) T cells, the defective development of tTregs in Cd28(-/-) mice may in part be due to increased Foxp3 ubiquitination and degradation targeted by Stub1 and Cbl-b. Treating Cd28(-/-) mice with a proteasome inhibitor completely rescues defective tTreg development in these mice. Therefore, Cbl-b, together with Stub1, ubiquitinate Foxp3, and regulate tTreg development.

Ex-vivo perfusion of donor hearts for human heart transplantation (PROCEED II): a prospective, open-label, multicentre, randomised non-inferiority trial.

BACKGROUND: The Organ Care System is the only clinical platform for ex-vivo perfusion of human donor hearts. The system preserves the donor heart in a warm beating state during transport from the donor hospital to the recipient hospital. We aimed to assess the clinical outcomes of the Organ Care System compared with standard cold storage of human donor hearts for transplantation. METHODS: We did this prospective, open-label, multicentre, randomised non-inferiority trial at ten heart-transplant centres in the USA and Europe. Eligible heart-transplant candidates (aged >18 years) were randomly assigned (1:1) to receive donor hearts preserved with either the Organ Care System or standard cold storage. Participants, investigators, and medical staff were not masked to group assignment. The primary endpoint was 30 day patient and graft survival, with a 10% non-inferiority margin. We did analyses in the intention-to-treat, as-treated, and per-protocol populations. This trial is registered with ClinicalTrials.gov, number NCT00855712. FINDINGS: Between June 29, 2010, and Sept 16, 2013, we randomly assigned 130 patients to the Organ Care System group (n=67) or the standard cold storage group (n=63). 30 day patient and graft survival rates were 94% (n=63) in the Organ Care System group and 97% (n=61) in the standard cold storage group (difference 2·8%, one-sided 95% upper confidence bound 8·8; p=0·45). Eight (13%) patients in the Organ Care System group and nine (14%) patients in the standard cold storage group had cardiac-related serious adverse events. INTERPRETATION: Heart transplantation using donor hearts adequately preserved with the Organ Care System or with standard cold storage yield similar short-term clinical outcomes. The metabolic assessment capability of the Organ Care System needs further study. FUNDING: TransMedics.

A novel 2q37 microdeletion containing human neural progenitors genes including STK25 results in severe developmental delay, epilepsy, and microcephaly.

2q37 microdeletion syndrome is a rare syndrome characterized by neurodevelopmental delay, bone, cardiovascular, and neurological alterations. This syndrome is typically associated with loss of genetic material of approximately 100 genes in the 2q37 band. However, the genes associated with neurodevelopmental phenotype in this syndrome are still unknown. We identified a deleted region of 496 kb by whole genome array CGH in a patient who fulfilled criteria for 2q37 microdeletion syndrome with developmental delay, microcephaly, hypoplasia of the corpus callosum, hand wringing, toe walking, and seizures. The deleted segment contains genes that are highly expressed in the developing human cortical plate and the subventricular zone (SVZ) in vivo and human neural progenitors in vitro, including SEPT2, THAP4, ATG4B, PPP1R7, and STK25. Network analysis revealed that STK25 was the most interacting gene associated with neural development in this deletion. Our report narrows the likely causative genomic region for microcephaly and neurodevelopmental delay in 2q37 microdeletion syndrome to a small genomic region enriched with neural progenitor genes that may represent an important locus for the development of the human cortex and corpus callosum.

Successful Management of Thrombosis of the Proximal Aorta after Implantation with a Biventricular Assist Device.

Continuous-flow ventricular assist devices (CVADs) are associated with a significant complication profile that includes thrombosis of the ascending aorta and aortic valve, thromboembolism, and stroke. Despite an increasing number of reports of thromboembolic complications related to CVADs, there is little in the literature to guide their management. This report describes successful management strategies used during two cases of thrombosis of the ascending aorta during biventricular CentriMag (Levitronix LLC, Waltham, MA) support, including using pre-existing cannulas to initiate cardiopulmonary bypass.

Surgical Outcomes and Genomic Insights of Nonclear Cell Renal Cell Carcinoma with Synchronous and Metachronous Nodal Disease.

INTRODUCTION: Oncological outcomes in patients with nonclear cell renal cell carcinoma (non-ccRCC) treated with surgery for locoregional nodal disease (ND) remain incompletely characterized. The objective was to investigate the characteristics and outcomes of non-ccRCC patients treated with lymph node dissection (LND) and salvage-LND (S-LND). METHODS: A total of 1627 patients underwent nephrectomy for nonmetastatic non-ccRCC at Memorial Sloan Kettering Cancer Center between 2007 and 2023. Histology was grouped as papillary, chromophobe, unclassified, and rare subtypes. Retrospective evaluation identified 2.5% (n = 40) of patients with nodal disease at time of nephrectomy (synchronous-ND) and 1.1% (n = 18) with metachronous nodal disease limited to the retroperitoneum (metachronous-ND). Patients' demographics and tumor characteristics were recorded and evaluated by univariate and multivariate cox regression models. Recurrence-free survival (RFS) and overall survival (OS) were estimated by the Kaplan-Meier method. Patients who underwent tumor DNA sequencing during their clinical course were considered for genomic analysis. RESULTS: OS trended toward longer in metachronous-ND (51 vs 105 months; P = .2), though 23% of patients with synchronous-ND were recurrence-free at 45 months median follow-up. In multivariate analysis, rare histologies were associated with decreased OS (P = .030) and metachronous-ND with improved OS (P = .036). RFS and OS after S-LND was 15 and 96 months, respectively. Late onset of metachronous-ND/recurrence was associated with improved OS (P = .008). Genetic alterations in SETD2, TP53, B2M, and FGFR3 were exclusively seen in synchronous-ND, and tumor mutation burden (TMB) was also higher in patients with synchronous-ND (P = .016). CONCLUSIONS: Patients with metachronous-ND tend to have prolonged OS compared to synchronous-ND, but a substantial portion of patients with synchronous-ND still enter a durable disease-free state following LND. S-LND can likewise provide long-term survival, particularly in patients with longer time to metachronous nodal recurrence. Synchronous-ND was associated with SETD2, TP53, and NF2 alteration as well as higher TMB.

A Phase 2 Trial of Talazoparib and Avelumab in Genomically Defined Metastatic Kidney Cancer.

BACKGROUND: Although different kidney cancers represent a heterogeneous group of malignancies, multiple subtypes including Von Hippel-Lindau (VHL)-altered clear cell renal cell carcinoma (ccRCC), fumarate hydratase (FH)- and succinate dehydrogenase (SDH)-deficient renal cell carcinoma (RCC), and renal medullary carcinoma (RMC) are affected by genomic instability. Synthetic lethality with poly ADP-ribose polymerase inhibitors (PARPis) has been suggested in preclinical models of these subtypes, and paired PARPis with immune checkpoint blockade (ICB) may achieve additive and/or synergistic effects in patients with previously treated advanced kidney cancers. OBJECTIVE: To evaluate combined PARPi + ICB in treatment-refractory metastatic kidney cancer. DESIGN, SETTING, AND PARTICIPANTS: We conducted a single-center, investigator-initiated phase 2 trial in two genomically selected advanced kidney cancer cohorts: (1) VHL-altered RCC with at least one prior ICB agent and one vascular endothelial growth factor (VEGF) inhibitor, and (2) FH- or SDH-deficient RCC with at least one prior ICB agent or VEGF inhibitor and RMC with at least one prior line of chemotherapy. INTERVENTION: Patients received talazoparib 1 mg daily plus avelumab 800 mg intravenously every 14 d in 28-d cycles. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was objective response rate (ORR) by Immune Response Evaluation Criteria in Solid Tumors at 4 mo, and the secondary endpoints included progression-free survival (PFS), overall survival, and safety. RESULTS AND LIMITATIONS: Cohort 1 consisted of ten patients with VHL-altered ccRCC. All patients had previously received ICB. The ORR was 0/9 patients; one patient was not evaluable due to missed doses. In this cohort, seven patients achieved stable disease (SD) as the best response. The median PFS was 3.5 mo (95% confidence interval [CI] 1.0, 3.9 mo). Cohort 2 consisted of eight patients; four had FH-deficient RCC, one had SDH-deficient RCC, and three had RMC. In this cohort, six patients had previously received ICB. The ORR was 0/8 patients; two patients achieved SD as the best response and the median PFS was 1.2 mo (95% CI 0.4, 2.9 mo). The most common treatment-related adverse events of all grades were fatigue (61%), anemia (28%), nausea (22%), and headache (22%). There were seven grade 3-4 and no grade 5 events. CONCLUSIONS: The first clinical study of combination PARPi and ICB therapy in advanced kidney cancer did not show clinical benefit in multiple genomically defined metastatic RCC cohorts or RMC. PATIENT SUMMARY: We conducted a study to look at the effect of two medications, talazoparib and avelumab, in patients with metastatic kidney cancer who had disease progression on standard treatment. Talazoparib blocks the normal activity of molecules called poly ADP-ribose polymerase, which then prevents tumor cells from repairing themselves and growing, while avelumab helps the immune system recognize and kill cancer cells. We found that the combination of these agents was safe but not effective in specific types of kidney cancer.

Nocturia, sleep and daytime function in stable heart failure.

BACKGROUND: The aim of this study was to evaluate nocturia severity and nocturia-related differences in sleep, daytime symptoms and functional performance among patients with stable heart failure (HF). METHODS AND RESULTS: In this cross-sectional observational study, we recruited 173 patients [mean age 60.3 ± 16.8 years; female n = 60 (35%); mean left ventricular ejection fraction 32 ± 14.6%] with stable chronic HF from HF disease management programs in the northeastern United States. Participants reported nocturia and completed a 6-minute walk test (6MWT), 1 night of ambulatory polysomnography, and the SF-36 Medical Outcomes Study, Epworth Sleepiness, Pittsburgh Sleep Quality Index, Multidimensional Assessment of Fatigue, and Centers for the Epidemiological Studies of Depression scales. Participants reported 0 (n = 30; 17.3%), 1-2 (n = 87; 50.2%), and ≥3 (n = 56; 32.4%) nightly episodes of nocturia. There were decreases in sleep duration and efficiency, REM and stage 3-4 sleep, physical function, and 6MWT distance and increases in the percentage of wake time after sleep onset, insomnia symptoms, fatigue, and sleepiness across levels of nocturia severity. CONCLUSIONS: Nocturia is common, severe, and closely associated with decrements in sleep and functional performance and increases in fatigue and sleepiness in patients with stable HF.

Implantable cardiac defibrillators and sudden death in recent onset nonischemic cardiomyopathy: results from IMAC2.

BACKGROUND: Given the potential for recovery in recent onset nonischemic cardiomyopathy (ROCM), the timing and need for implantable cardioverter-defibrillator (ICDs) remains controversial. We examined the utilization of ICDs and the impact on survival for subjects with ROCM. METHODS AND RESULTS: An National Heart, Lung, and Blood Institute sponsored registry enrolled 373 subjects with ROCM, all with a left ventricular ejection fraction (LVEF) ≤0.40 and ≤6 months of symptoms. The mean age was 45 ± 14 years, 38% were female, 21% black, 75% New York Heart Association II/III, and the mean LVEF was 0.24 ± 0.08. Survival was comparable for subjects with an ICD within 1 month of entry (n = 43, 1/2/3 year % survival = 97/97/92) and those with no ICD at 1 month (n = 330, % survival = 98/97/95, P = .30) and between those with and without an ICD at 6 months (ICD, n = 73, 1/2/3 year % survival = 98/98/95; no ICD, n = 300, % survival = 98/96/95, P = .95). There were only 6 sudden cardiac deaths (SCD) noted (% survival free from SCD = 99/98/97) and these occurred in 1.9% of subjects without ICD and 0.9% of those with a device (P = .50). CONCLUSIONS: In a multicenter cohort of ROCM the risk of SCD was low at 1% per year. Early ICD placement did not impact survival and can be deferred while assessing potential for myocardial recovery.

Myocardial recovery in peripartum cardiomyopathy: prospective comparison with recent onset cardiomyopathy in men and nonperipartum women.

BACKGROUND: Whether myocardial recovery occurs more frequently in peripartum cardiomyopathy (PPCM) than in recent onset cardiomyopathies in men and nonperipartum women has not been prospectively evaluated. This was examined through an analysis of outcomes in the Intervention in Myocarditis and Acute Cardiomyopathy 2 (IMAC2) registry. METHODS AND RESULTS: IMAC2 enrolled 373 subjects with recent onset nonischemic dilated cardiomyopathy. Left ventricular ejection fraction (LVEF) was assessed at entry and 6 months, and subjects followed for up to 4 years. Myocardial recovery was compared between men (group 1), nonperipartum women (group 2) and subjects with PPCM (group 3). The cohort included 230 subjects in group 1, 104 in group 2, and 39 in group 3. The mean LVEF at baseline in groups 1, 2, and 3 was 0.23 ± 0.08, 0.24 ± 0.08, and 0.27 ± 0.07 (P = .04), and at 6 months was 0.39 ± 0.12, 0.42 ± 0.11, and 0.45 ± 0.14 (P = .007). Subjects in group 3 had a much greater likelihood of achieving an LVEF >0.50 at 6 months than groups 1 or 2 (19 %, 34%, and 48% respectively, P = .002). CONCLUSIONS: Prospective evaluation confirms myocardial recovery is greatest in women with PPCM, poorest in men, and intermediate in nonperipartum women. On contemporary therapy, nearly half of women with PPCM normalize cardiac function by 6 months.

Left ventricular assist device support and myocardial recovery in recent onset cardiomyopathy.

BACKGROUND: Left ventricular assist device (LVAD) support as bridge to recovery (BTR) is uncommon for subjects with chronic heart failure. Myocardial recovery is more evident in recent onset nonischemic cardiomyopathy (ROCM); however, the prevalence of BTR in this subset has not been addressed. METHODS AND RESULTS: We examined the use of LVAD support for subjects with ROCM in the Intervention in Myocarditis and Acute Cardiomyopathy 2 (IMAC2) study. The overall cohort (n = 373) was 38% female, 21% black, with a mean age of 45 ± 14 years. LVAD support was used in 3.8% (n = 14, 43% female, age 32 ± 10). Of LVAD subjects, 57% (8/14) were BTR, including 73% (8/11) of subjects with symptoms ≤4 months at the time of support. Left ventricular end-diastolic diameter (LVEDD) was smaller in BTR than nonrecovered (NR) subjects (P = .04). Myocardial inflammation was more common in BTR (75% versus 0%, P = .005), whereas fibrosis was less evident (25% versus 100%, P = .005). Of BTR subjects, 7/8 (87.5%) were alive and free of transplant with median follow-up of 19 months. CONCLUSION: In a multicenter registry of ROCM, BTR was common and occurred in the majority of subjects requiring LVAD support. Histology and LVEDD may assist in predicting potential for BTR in ROCM.

Molecular Characterization of the Tumor Microenvironment in Renal Medullary Carcinoma.

Renal medullary carcinoma (RMC) is a highly aggressive disease associated with sickle hemoglobinopathies and universal loss of the tumor suppressor gene SMARCB1. RMC has a relatively low rate of incidence compared with other renal cell carcinomas (RCCs) that has hitherto made molecular profiling difficult. To probe this rare disease in detail we performed an in-depth characterization of the RMC tumor microenvironment using a combination of genomic, metabolic and single-cell RNA-sequencing experiments on tissue from a representative untreated RMC patient, complemented by retrospective analyses of archival tissue and existing published data. Our study of the tumor identifies a heterogenous population of malignant cell states originating from the thick ascending limb of the Loop of Henle within the renal medulla. Transformed RMC cells displayed the hallmarks of increased resistance to cell death by ferroptosis and proteotoxic stress driven by MYC-induced proliferative signals. Specifically, genomic characterization of RMC tumors provides substantiating evidence for the recently proposed dependence of SMARCB1-difficient cancers on proteostasis modulated by an intact CDKN2A-p53 pathway. We also provide evidence that increased cystine-mTORC-GPX4 signaling plays a role in protecting transformed RMC cells against ferroptosis. We further propose that RMC has an immune landscape comparable to that of untreated RCCs, including heterogenous expression of the immune ligand CD70 within a sub-population of tumor cells. The latter could provide an immune-modulatory role that serves as a viable candidate for therapeutic targeting.

A new flow cytometry assay identifies recipient IgG subtype antibodies binding donor cells: increasing donor availability for highly sensitised patients.

Objectives: There are four immunoglobulin (IgG) subtypes that have varying complement-activating ability: strong (IgG3 and IgG1) and weak (IgG2 and IgG4). The standard flow cytometric crossmatch (FCM) assay does not distinguish between the various subtypes of the IgG molecule. This study outlines the development and use of a novel cell-based IgG subtype-specific FCM assay that is able to detect the presence of and quantitate the IgG subtypes bound to donor cells. Methods: A six-colour lyophilised reagent was designed that specifically detects the four IgG subtypes, as well as distinguishes between T cells and B cells in the lymphocyte population. To test the efficacy of this reagent, a retrospective evaluation of a group of highly sensitised patients awaiting heart and kidney transplant was carried out, who, because of positive standard FCM results, had been deemed incompatible with numerous prior potential donors. Results: Observations in this study demonstrate that the positive standard FCM results were mainly because of the presence of noncomplement-activating IgG2 or IgG4 antibodies. The results were supported by the absence of C3d-binding donor-specific antibodies (DSA) and a negative complement-dependent cytotoxicity crossmatch (CDC). Conclusion: Preliminary data presented in this study demonstrate the reliability of the novel IgG subtype assay to detect the presence of pretransplant, complement-activating antibodies bound to donor cells. The knowledge gained from the IgG subtype assay and the C3d-binding specificities of DSAs provides improved identification of donor suitability in pretransplant patients, potentially increasing the number of transplants.